Dépouillements

Degradation of antineoplastic cytarabine in aqueous solution by gamma radiation / R. Ocampo-Pérez in Chemical engineering journal, Vol. 174 N° 1 (Octobre 2011) 

Public ISBD [article]  in Chemical engineering journal > Vol. 174 N° 1 (Octobre 2011) . - PP.1-8 Titre : Degradation of antineoplastic cytarabine in aqueous solution by gamma radiation Type de document : texte imprimé Auteurs : R. Ocampo-Pérez, Auteur ; J. Rivera-Utrilla, Auteur ; M. Sánchez-Polo, Auteur Année de publication : 2012 Article en page(s) : PP.1-8 Note générale : Génie chimique Langues : Anglais (eng) Mots-clés : Antineoplastic  Cytarabine  Gamma  radiation  Degradation Résumé : The aim of this study was to determine the effectiveness of gamma radiation to degrade cytarabine in aqueous solution. The effect of dose rate, initial cytarabine concentration, medium pH, and the presence of H2O2, Cl−, CO32−, NO3−, NO2− and organic matter was studied. Furthermore, the influence of the chemical composition of water on cytarabine degradation was evaluated by using different water matrix (ultrapure water, surface water, groundwater, and wastewater) and the variations in total organic carbon concentration and toxicity were also studied. Results show that cytarabine radiolysis fits pseudo-first order kinetics. The dose constants determined in this study ranged from 0.002 × 10−2 to 1.32 × 10−2 Gy−1, whereas the initial radiation-chemical yield ranged from 0.033 to 0.94 μmol J−1. Cytarabine degradation in the presence of Cl−, CO32−, NO3−, NO2− and humic acid showed a decrease in dose constants with the increase in present species concentration, largely due to competition of cytarabine with Cl−, CO32−, NO3−, NO2− and humic acid by the reactive species generated, mainly HOradical dot radicals. Cytarabine degradation was slightly improved by the presence of small amounts of H2O2, which acted as promoter of HOradical dot radicals. However, the dose constant decreased at high concentrations of H2O2 (concentrations above 1 mM) due to inhibition of HOradical dot radicals by recombination reactions. The effectiveness of gamma radiation was markedly reduced in wastewater due to inhibition of the reactive species by the high organic matter and anion content of the water. This study shows that it is not possible to completely mineralize organic matter in ultrapure water, surface water, groundwater, or wastewater at the radiation doses used ISSN : 1385-8947 En ligne : http://www.sciencedirect.com/science/article/pii/S1385894711008448 [article] Degradation of antineoplastic cytarabine in aqueous solution by gamma radiation [texte imprimé] / R. Ocampo-Pérez, Auteur ; J. Rivera-Utrilla, Auteur ; M. Sánchez-Polo, Auteur . - 2012 . - PP.1-8. Génie chimique Langues : Anglais (eng) in Chemical engineering journal > Vol. 174 N° 1 (Octobre 2011) . - PP.1-8 Mots-clés : Antineoplastic  Cytarabine  Gamma  radiation  Degradation Résumé : The aim of this study was to determine the effectiveness of gamma radiation to degrade cytarabine in aqueous solution. The effect of dose rate, initial cytarabine concentration, medium pH, and the presence of H2O2, Cl−, CO32−, NO3−, NO2− and organic matter was studied. Furthermore, the influence of the chemical composition of water on cytarabine degradation was evaluated by using different water matrix (ultrapure water, surface water, groundwater, and wastewater) and the variations in total organic carbon concentration and toxicity were also studied. Results show that cytarabine radiolysis fits pseudo-first order kinetics. The dose constants determined in this study ranged from 0.002 × 10−2 to 1.32 × 10−2 Gy−1, whereas the initial radiation-chemical yield ranged from 0.033 to 0.94 μmol J−1. Cytarabine degradation in the presence of Cl−, CO32−, NO3−, NO2− and humic acid showed a decrease in dose constants with the increase in present species concentration, largely due to competition of cytarabine with Cl−, CO32−, NO3−, NO2− and humic acid by the reactive species generated, mainly HOradical dot radicals. Cytarabine degradation was slightly improved by the presence of small amounts of H2O2, which acted as promoter of HOradical dot radicals. However, the dose constant decreased at high concentrations of H2O2 (concentrations above 1 mM) due to inhibition of HOradical dot radicals by recombination reactions. The effectiveness of gamma radiation was markedly reduced in wastewater due to inhibition of the reactive species by the high organic matter and anion content of the water. This study shows that it is not possible to completely mineralize organic matter in ultrapure water, surface water, groundwater, or wastewater at the radiation doses used ISSN : 1385-8947 En ligne : http://www.sciencedirect.com/science/article/pii/S1385894711008448

Bioseparation of Pb (II) and Cd (II) from aqueoussolution using corkwastebiomass. / Montserrat Lopez-Mesas in Chemical engineering journal, Vol. 174 N° 1 (Octobre 2011) 

Public ISBD [article]  in Chemical engineering journal > Vol. 174 N° 1 (Octobre 2011) . - pp.9-17 Titre : Bioseparation of Pb (II) and Cd (II) from aqueoussolution using corkwastebiomass. : Modeling and optimization of the parameters of the biosorption step Type de document : texte imprimé Auteurs : Montserrat Lopez-Mesas, Auteur ; Enrique Ruperto Navarrete, Auteur ; Fernando Carrillo, Auteur Année de publication : 2012 Article en page(s) : pp.9-17 Note générale : Génie chimique Langues : Anglais (eng) Mots-clés : Cork  Heavy  metals  Kinetic  Isotherm  Biosorption Résumé : In this work the ability of corkwastes to remove Cd(II) and Pb(II) from aqueoussolutions has been studied. The kinetics of the biosorption system, the influence of the aqueous pH and the initial metal concentration on the metal uptake were investigated, showing a pH dependent profile. The maximum sorption for both metals was found at pH 5, independently that if the metals were in individual solutions or mixed. When a solution of the mixed metals were studied, a reduction in the Cd(II) uptake was observed showing a clear competition between the metals which was corroborated by the P-factor approach, behavior probably due to a lower attraction of this metal towards the corresponding active groups of the cork. Finally, the cork has been evaluated by FTIR and SEM in order to determine if the biosorption process modifies its chemical structure and morphology, respectively. Cork has been proved to be an efficient biomaterial useful for heavy metal separation purposes that is not altered by the process. ISSN : 1385-8947 En ligne : http://www.sciencedirect.com/science/article/pii/S1385894711008539 [article] Bioseparation of Pb (II) and Cd (II) from aqueoussolution using corkwastebiomass. : Modeling and optimization of the parameters of the biosorption step [texte imprimé] / Montserrat Lopez-Mesas, Auteur ; Enrique Ruperto Navarrete, Auteur ; Fernando Carrillo, Auteur . - 2012 . - pp.9-17. Génie chimique Langues : Anglais (eng) in Chemical engineering journal > Vol. 174 N° 1 (Octobre 2011) . - pp.9-17 Mots-clés : Cork  Heavy  metals  Kinetic  Isotherm  Biosorption Résumé : In this work the ability of corkwastes to remove Cd(II) and Pb(II) from aqueoussolutions has been studied. The kinetics of the biosorption system, the influence of the aqueous pH and the initial metal concentration on the metal uptake were investigated, showing a pH dependent profile. The maximum sorption for both metals was found at pH 5, independently that if the metals were in individual solutions or mixed. When a solution of the mixed metals were studied, a reduction in the Cd(II) uptake was observed showing a clear competition between the metals which was corroborated by the P-factor approach, behavior probably due to a lower attraction of this metal towards the corresponding active groups of the cork. Finally, the cork has been evaluated by FTIR and SEM in order to determine if the biosorption process modifies its chemical structure and morphology, respectively. Cork has been proved to be an efficient biomaterial useful for heavy metal separation purposes that is not altered by the process. ISSN : 1385-8947 En ligne : http://www.sciencedirect.com/science/article/pii/S1385894711008539

Preparation, characterization and application of a [copper (II) / ethylenediamine – cotton] complex for the removal of AB25 from aqueous solution in a laboratory scale column. / Amel El Ghali in Chemical engineering journal, Vol. 174 N° 1 (Octobre 2011) 

Public ISBD [article]  in Chemical engineering journal > Vol. 174 N° 1 (Octobre 2011) . - pp.18-26 Titre : Preparation, characterization and application of a [copper (II) / ethylenediamine – cotton] complex for the removal of AB25 from aqueous solution in a laboratory scale column. Type de document : texte imprimé Auteurs : Amel El Ghali, Auteur ; Mohamed Hassen V. Baouab, Auteur ; Mohamed Sadok Roudesli, Auteur Année de publication : 2012 Article en page(s) : pp.18-26 Note générale : Génie chimique Langues : Anglais (eng) Mots-clés : Cotton  Heavy  metal  Kinetics  Dyes  Fixed  bed  adsorption  Modeling Résumé : Ethylenediamine grafted cellulosic fibers (ED–cotton) were synthesized by the reaction of chlorodeoxycellulose (CDC) with (ED). The performance of the modified materials was characterized by Fourier transform-infrared (FTIR), atomic force microscopy (AFM) and elemental analysis of nitrogen. The prepared ED–cotton support was assessed for the removal of copper ions from aqueoussolutions using a batch process. The effects of pH, copper initial concentration and contact time were investigated. The kinetic adsorption was found to follow the pseudo-second-order kinetic model. Results revealed the formation of a 1:1 complex as proved by the adsorption limit. The binary system [Cu(II)/ED–cotton] was then tested in a bed fixed column for the adsorption of Acid Blue 25, as ligand in the metal-coordinating process. The effects of various experimental conditions, such as the flow rate, bed height and internal diameter, were studied. The Bed Depth Service Time (BDST) model was found suitable for the description of breakthrough curves at all experimental conditions. ISSN : 1385-8947 En ligne : http://www.sciencedirect.com/science/article/pii/S1385894711008734 [article] Preparation, characterization and application of a [copper (II) / ethylenediamine – cotton] complex for the removal of AB25 from aqueous solution in a laboratory scale column. [texte imprimé] / Amel El Ghali, Auteur ; Mohamed Hassen V. Baouab, Auteur ; Mohamed Sadok Roudesli, Auteur . - 2012 . - pp.18-26. Génie chimique Langues : Anglais (eng) in Chemical engineering journal > Vol. 174 N° 1 (Octobre 2011) . - pp.18-26 Mots-clés : Cotton  Heavy  metal  Kinetics  Dyes  Fixed  bed  adsorption  Modeling Résumé : Ethylenediamine grafted cellulosic fibers (ED–cotton) were synthesized by the reaction of chlorodeoxycellulose (CDC) with (ED). The performance of the modified materials was characterized by Fourier transform-infrared (FTIR), atomic force microscopy (AFM) and elemental analysis of nitrogen. The prepared ED–cotton support was assessed for the removal of copper ions from aqueoussolutions using a batch process. The effects of pH, copper initial concentration and contact time were investigated. The kinetic adsorption was found to follow the pseudo-second-order kinetic model. Results revealed the formation of a 1:1 complex as proved by the adsorption limit. The binary system [Cu(II)/ED–cotton] was then tested in a bed fixed column for the adsorption of Acid Blue 25, as ligand in the metal-coordinating process. The effects of various experimental conditions, such as the flow rate, bed height and internal diameter, were studied. The Bed Depth Service Time (BDST) model was found suitable for the description of breakthrough curves at all experimental conditions. ISSN : 1385-8947 En ligne : http://www.sciencedirect.com/science/article/pii/S1385894711008734

Toxicity and biodegradability of ionic liquids / Guillermo Quijano in Chemical engineering journal, Vol. 174 N° 1 (Octobre 2011) 

Public ISBD [article]  in Chemical engineering journal > Vol. 174 N° 1 (Octobre 2011) . - pp.27-32 Titre : Toxicity and biodegradability of ionic liquids : New perspectives towards whole - cellbiotechnological applications Type de document : texte imprimé Auteurs : Guillermo Quijano, Auteur ; Annabelle Couvert, Auteur ; Abdeltif Amrane, Auteur Année de publication : 2012 Article en page(s) : pp.27-32 Note générale : Génie chimique Langues : Anglais (eng) Mots-clés : Environment  Ionic  liquids  Ionic  liquids  Toxicity  Activated  sludge Résumé : The potential of four ILs for whole-cellbiotechnological processes was evaluated in terms of toxicity and biodegradability. From the four ILs tested, only Aliquat completely inhibited the microbial glucose uptake at a concentration of 5%, while [PEGMIM][PF6] was completely soluble in water. Therefore, these ILs were discarded for further studies. On the other hand, [BMIM][PF6] and [BMIM][NTF2] were not toxic at a concentration of 5% (v/v) (specific concentrations of 170 and 180 gIL gBiomass−1, respectively), while IL addition at 10% (v/v) slightly inhibited the metabolic activity relative to controls deprived of IL. Addition of both [BMIM][PF6] and [BMIM][NTF2] produced an acclimation time of approximately 24 h before the microorganisms were able to uptake the substrate. Further experiments on IL toxicity due to long-term fluoride (F−) release showed that despite the fact that F− was detected in the aqueous phase, its concentration was very low (≤2.98 mg L−1) and hence not toxic for the microorganisms. Finally, short- and long-term biodegradability tests showed that neither [BMIM][PF6] nor [BMIM][NTF2] was biodegradable. Therefore, [BMIM][PF6] and [BMIM][NTF2] can be considered as compatible with whole-cellbiotechnological processes. ISSN : 1385-8947 En ligne : http://www.sciencedirect.com/science/article/pii/S1385894711008990 [article] Toxicity and biodegradability of ionic liquids : New perspectives towards whole - cellbiotechnological applications [texte imprimé] / Guillermo Quijano, Auteur ; Annabelle Couvert, Auteur ; Abdeltif Amrane, Auteur . - 2012 . - pp.27-32. Génie chimique Langues : Anglais (eng) in Chemical engineering journal > Vol. 174 N° 1 (Octobre 2011) . - pp.27-32 Mots-clés : Environment  Ionic  liquids  Ionic  liquids  Toxicity  Activated  sludge Résumé : The potential of four ILs for whole-cellbiotechnological processes was evaluated in terms of toxicity and biodegradability. From the four ILs tested, only Aliquat completely inhibited the microbial glucose uptake at a concentration of 5%, while [PEGMIM][PF6] was completely soluble in water. Therefore, these ILs were discarded for further studies. On the other hand, [BMIM][PF6] and [BMIM][NTF2] were not toxic at a concentration of 5% (v/v) (specific concentrations of 170 and 180 gIL gBiomass−1, respectively), while IL addition at 10% (v/v) slightly inhibited the metabolic activity relative to controls deprived of IL. Addition of both [BMIM][PF6] and [BMIM][NTF2] produced an acclimation time of approximately 24 h before the microorganisms were able to uptake the substrate. Further experiments on IL toxicity due to long-term fluoride (F−) release showed that despite the fact that F− was detected in the aqueous phase, its concentration was very low (≤2.98 mg L−1) and hence not toxic for the microorganisms. Finally, short- and long-term biodegradability tests showed that neither [BMIM][PF6] nor [BMIM][NTF2] was biodegradable. Therefore, [BMIM][PF6] and [BMIM][NTF2] can be considered as compatible with whole-cellbiotechnological processes. ISSN : 1385-8947 En ligne : http://www.sciencedirect.com/science/article/pii/S1385894711008990

Batch and fixed - bedadsorption of 2 , 4 - dichlorophenoxyaceticacid onto oilpalm frond activated carbon / J.M. Salman in Chemical engineering journal, Vol. 174 N° 1 (Octobre 2011) 

Public ISBD [article]  in Chemical engineering journal > Vol. 174 N° 1 (Octobre 2011) . - pp.33-40 Titre : Batch and fixed - bedadsorption of 2 , 4 - dichlorophenoxyaceticacid onto oilpalm frond activated carbon Type de document : texte imprimé Auteurs : J.M. Salman, Auteur ; V.O. Njoku, Auteur ; B.H. Hameed, Auteur Année de publication : 2012 Article en page(s) : pp.33-40 Note générale : Génie chimique Langues : Anglais (eng) Mots-clés : 2,4-D  Breakthrough  characteristics  Column  studies  Kinetics  Pesticide Résumé : Adsorption of 2,4-dichlorophenoxyaceticacid (2,4-D) from aqueous solution onto activated carbon derived from oilpalm frond (PFAC) was investigated using batch and column systems. The effects of contact time, initial concentration of 2,4-D, temperature and pH on the adsorption were studied using the batch technique. The adsorption kinetic data were analyzed using the pseudo-first- and pseudo-second-order models and the results showed that the pseudo-second-order model best described the adsorption kinetics. The adsorption isotherms of 2,4-D on PFAC were analyzed using the Langmuir and Freundlich isotherm models and the results showed that a better fit was achieved with the Langmuir model. The determined thermodynamic parameters, ΔG°, ΔH° and ΔS° showed that the adsorption of 2,4-D onto PFAC was feasible, spontaneous and exothermic under the examined conditions. For the column studies, the effects of initial concentration of 2,4-D, bed-height and flow rate on the adsorption of 2,4-D onto PFAC were investigated. The highest bed capacity of 45 mg/g at 150 mg/L 2,4-D initial concentration, 10 mL/min flow rate and 3 cm PFAC bed-height was obtained. Three models, namely Bohart–Adams, Thomas and Yoon–Nelson, were applied to predict the breakthrough curves and to determine the characteristic parameters. The average relative error method was used to determine the model with the best fit and it was found that the Bohart–Adams model best described the continuous adsorption of 2,4-D onto PFAC. ISSN : 1385-8947 En ligne : http://www.sciencedirect.com/science/article/pii/S1385894711009697 [article] Batch and fixed - bedadsorption of 2 , 4 - dichlorophenoxyaceticacid onto oilpalm frond activated carbon [texte imprimé] / J.M. Salman, Auteur ; V.O. Njoku, Auteur ; B.H. Hameed, Auteur . - 2012 . - pp.33-40. Génie chimique Langues : Anglais (eng) in Chemical engineering journal > Vol. 174 N° 1 (Octobre 2011) . - pp.33-40 Mots-clés : 2,4-D  Breakthrough  characteristics  Column  studies  Kinetics  Pesticide Résumé : Adsorption of 2,4-dichlorophenoxyaceticacid (2,4-D) from aqueous solution onto activated carbon derived from oilpalm frond (PFAC) was investigated using batch and column systems. The effects of contact time, initial concentration of 2,4-D, temperature and pH on the adsorption were studied using the batch technique. The adsorption kinetic data were analyzed using the pseudo-first- and pseudo-second-order models and the results showed that the pseudo-second-order model best described the adsorption kinetics. The adsorption isotherms of 2,4-D on PFAC were analyzed using the Langmuir and Freundlich isotherm models and the results showed that a better fit was achieved with the Langmuir model. The determined thermodynamic parameters, ΔG°, ΔH° and ΔS° showed that the adsorption of 2,4-D onto PFAC was feasible, spontaneous and exothermic under the examined conditions. For the column studies, the effects of initial concentration of 2,4-D, bed-height and flow rate on the adsorption of 2,4-D onto PFAC were investigated. The highest bed capacity of 45 mg/g at 150 mg/L 2,4-D initial concentration, 10 mL/min flow rate and 3 cm PFAC bed-height was obtained. Three models, namely Bohart–Adams, Thomas and Yoon–Nelson, were applied to predict the breakthrough curves and to determine the characteristic parameters. The average relative error method was used to determine the model with the best fit and it was found that the Bohart–Adams model best described the continuous adsorption of 2,4-D onto PFAC. ISSN : 1385-8947 En ligne : http://www.sciencedirect.com/science/article/pii/S1385894711009697

Adsorption of pesticides from aqueoussolution onto bananastalkactivated carbon / J.M. Salman in Chemical engineering journal, Vol. 174 N° 1 (Octobre 2011) 

Public ISBD [article]  in Chemical engineering journal > Vol. 174 N° 1 (Octobre 2011) . - pp.41-48 Titre : Adsorption of pesticides from aqueoussolution onto bananastalkactivated carbon Type de document : texte imprimé Auteurs : J.M. Salman, Auteur ; V.O. Njoku, Auteur ; B.H. Hameed, Auteur Année de publication : 2012 Article en page(s) : pp.41-48 Note générale : Génie chimique Langues : Anglais (eng) Mots-clés : 2,4-Dichlorophenoxyacetic  acid  Bentazon  Isotherm  Kinetic  Thermodynamic Résumé : Activated carbon was prepared from bananastalk by potassium hydroxide (KOH) and carbon dioxide (CO2) activation and its ability to remove the pesticides, 2,4-dichlorophenoxyacetic acid (2,4-D) and bentazon was explored. The bananastalkactivated carbon (BSAC) was characterized by Fourier transform infrared spectroscopy (FT-IR) analysis. The adsorption kinetic data were analyzed using two kinetic models: the pseudo-first-order and pseudo-second-order models. The adsorption kinetics was better represented by the pseudo-second-order model. The equilibrium adsorption data obtained at 30, 40 and 50 °C were analyzed by Langmuir and Freundlich isotherm models and results showed that it was better described by the Freundlich model. Higher adsorption capacity observed for 2,4-D than bentazon were attributed to the presence of electron-withdrawing –Cl groups on the aromatic ring and smaller molecular size of 2,4-D. The thermodynamic parameters, ΔG°, ΔH° and ΔS° determined, showed that the adsorption of 2,4-D and bentazon onto BSAC was feasible, spontaneous and exothermic. The results showed that BSAC is an efficient adsorbent for the adsorptive removal of 2,4-D and bentazon from aqueoussolutions. ISSN : 1385-8947 En ligne : http://www.sciencedirect.com/science/article/pii/S1385894711009715 [article] Adsorption of pesticides from aqueoussolution onto bananastalkactivated carbon [texte imprimé] / J.M. Salman, Auteur ; V.O. Njoku, Auteur ; B.H. Hameed, Auteur . - 2012 . - pp.41-48. Génie chimique Langues : Anglais (eng) in Chemical engineering journal > Vol. 174 N° 1 (Octobre 2011) . - pp.41-48 Mots-clés : 2,4-Dichlorophenoxyacetic  acid  Bentazon  Isotherm  Kinetic  Thermodynamic Résumé : Activated carbon was prepared from bananastalk by potassium hydroxide (KOH) and carbon dioxide (CO2) activation and its ability to remove the pesticides, 2,4-dichlorophenoxyacetic acid (2,4-D) and bentazon was explored. The bananastalkactivated carbon (BSAC) was characterized by Fourier transform infrared spectroscopy (FT-IR) analysis. The adsorption kinetic data were analyzed using two kinetic models: the pseudo-first-order and pseudo-second-order models. The adsorption kinetics was better represented by the pseudo-second-order model. The equilibrium adsorption data obtained at 30, 40 and 50 °C were analyzed by Langmuir and Freundlich isotherm models and results showed that it was better described by the Freundlich model. Higher adsorption capacity observed for 2,4-D than bentazon were attributed to the presence of electron-withdrawing –Cl groups on the aromatic ring and smaller molecular size of 2,4-D. The thermodynamic parameters, ΔG°, ΔH° and ΔS° determined, showed that the adsorption of 2,4-D and bentazon onto BSAC was feasible, spontaneous and exothermic. The results showed that BSAC is an efficient adsorbent for the adsorptive removal of 2,4-D and bentazon from aqueoussolutions. ISSN : 1385-8947 En ligne : http://www.sciencedirect.com/science/article/pii/S1385894711009715

Phenolremoval from aqueous solution by activated carbon produced from avocado kernel seeds / Liana Alvares Rodrigues in Chemical engineering journal, Vol. 174 N° 1 (Octobre 2011) 

Public ISBD [article]  in Chemical engineering journal > Vol. 174 N° 1 (Octobre 2011) . - pp.49-57 Titre : Phenolremoval from aqueous solution by activated carbon produced from avocado kernel seeds Type de document : texte imprimé Auteurs : Liana Alvares Rodrigues, Auteur ; Maria Lucia Caetano Pinto Silva, Auteur ; Manoel Orlando Alvarez-Mendes, Auteur Année de publication : 2012 Article en page(s) : pp.49-57 Note générale : Génie chimique Langues : Anglais (eng) Mots-clés : Adsorption  Activated  carbon  Avocado  kernel  Phenol Résumé : Activatedcarbon derived from avocado kernels (AAC) was evaluated for its ability to remove phenol. The Brunauer–Emmett–Teller (BET) surface area of the AAC was 206 m2 g−1 and the total pore volume was 0.100 cm3 g−1. The kinetic of the adsorption process was described by a pseudo-second-order rate model. The maximum uptake was obtained at pH values between 4 and 8.5. The optimum adsorbent dose obtained was 0.1 g. The thermodynamic parameters exhibited the feasibility and the spontaneous nature of the adsorption process. Adsorption isotherms showed that the interaction of phenol with AAC surface was described by a localized monolayer adsorption. The adsorption mechanism was discussed based on experimental results, and the π–π interactions were considered to be an important parameter in the adsorption process. The adsorbent regeneration was investigated using several types of desorbing agents, but no agent show any promising result. The results showed that the prepared activatedcarbon was an effective adsorbent for phenolremoval from aqueoussolution. ISSN : 1385-8947 En ligne : http://www.sciencedirect.com/science/article/pii/S1385894711009727 [article] Phenolremoval from aqueous solution by activated carbon produced from avocado kernel seeds [texte imprimé] / Liana Alvares Rodrigues, Auteur ; Maria Lucia Caetano Pinto Silva, Auteur ; Manoel Orlando Alvarez-Mendes, Auteur . - 2012 . - pp.49-57. Génie chimique Langues : Anglais (eng) in Chemical engineering journal > Vol. 174 N° 1 (Octobre 2011) . - pp.49-57 Mots-clés : Adsorption  Activated  carbon  Avocado  kernel  Phenol Résumé : Activatedcarbon derived from avocado kernels (AAC) was evaluated for its ability to remove phenol. The Brunauer–Emmett–Teller (BET) surface area of the AAC was 206 m2 g−1 and the total pore volume was 0.100 cm3 g−1. The kinetic of the adsorption process was described by a pseudo-second-order rate model. The maximum uptake was obtained at pH values between 4 and 8.5. The optimum adsorbent dose obtained was 0.1 g. The thermodynamic parameters exhibited the feasibility and the spontaneous nature of the adsorption process. Adsorption isotherms showed that the interaction of phenol with AAC surface was described by a localized monolayer adsorption. The adsorption mechanism was discussed based on experimental results, and the π–π interactions were considered to be an important parameter in the adsorption process. The adsorbent regeneration was investigated using several types of desorbing agents, but no agent show any promising result. The results showed that the prepared activatedcarbon was an effective adsorbent for phenolremoval from aqueoussolution. ISSN : 1385-8947 En ligne : http://www.sciencedirect.com/science/article/pii/S1385894711009727

Solid phasepre - concentration of cobalt (II) using pyridine – thiocyanate reagents / Raja Saha in Chemical engineering journal, Vol. 174 N° 1 (Octobre 2011) 

Public ISBD [article]  in Chemical engineering journal > Vol. 174 N° 1 (Octobre 2011) . - pp.58-67 Titre : Solid phasepre - concentration of cobalt (II) using pyridine – thiocyanate reagents : X - ray crystal structure of the extracted ternary cobalt (II) complex Type de document : texte imprimé Auteurs : Raja Saha, Auteur ; Animesh Sahana, Auteur ; Sudipta Das, Auteur Année de publication : 2012 Article en page(s) : pp.58-67 Note générale : Génie chimique Langues : Anglais (eng) Mots-clés : Co(II)  Pyridine-2,6-dimethanol  Thiocyanate  Crystalstructure  Chelation  Flame  atomic  absorption  spectrometry Résumé : Mixture of pyridine-2,6-dimethanol (PDM) and thiocyanate (SCN−) (1:1, mole ratio) immobilized on silica served as a very efficient sorbent for selective retention of Co(II) from other associated metal ions at trace level. The maximum sorption capacity for Co(II) was found to be 0.203 mmol g−1 at pH 9.0. Sorbed Co(II) was completely eluted by 3.5 mL of 3 mol L−1 HCl and measured using flame atomic absorption spectrometer (FAAS). The structure of the extracted Co(II) complex was confirmed by single crystalX-raystructure and Fourier transform infrared (FTIR) spectroscopy. Thermo gravimetric analysis (TGA) of the chelated Co(II) complex revealed its stability at the optimum extraction temperature (55 °C). The method was reproducible with a relative standard deviation (RSD) of 0.6% (N = 10) with three sigma detection limit (N = 10) of 0.6 μg g−1. A pre-concentration factor, 94 was achieved. Interferences from Mn2+ and Cu2+ ions were eliminated by prior oxidation of Mn2+ by KIO4 to MnO4− and masking of Cu2+ with NH4SCN, respectively. A plausible mechanism for the selective extraction of Co(II) was attributed to the formation of a first order water insoluble inner–metallic complex as confirmed by the single crystalX-raystructure analysis. The developed method has been tested for trace level separation and estimation of cobalt in some certified reference materials. Analyses of some biological and environmental samples were performed. ISSN : 1385-8947 En ligne : http://www.sciencedirect.com/science/article/pii/S1385894711009910 [article] Solid phasepre - concentration of cobalt (II) using pyridine – thiocyanate reagents : X - ray crystal structure of the extracted ternary cobalt (II) complex [texte imprimé] / Raja Saha, Auteur ; Animesh Sahana, Auteur ; Sudipta Das, Auteur . - 2012 . - pp.58-67. Génie chimique Langues : Anglais (eng) in Chemical engineering journal > Vol. 174 N° 1 (Octobre 2011) . - pp.58-67 Mots-clés : Co(II)  Pyridine-2,6-dimethanol  Thiocyanate  Crystalstructure  Chelation  Flame  atomic  absorption  spectrometry Résumé : Mixture of pyridine-2,6-dimethanol (PDM) and thiocyanate (SCN−) (1:1, mole ratio) immobilized on silica served as a very efficient sorbent for selective retention of Co(II) from other associated metal ions at trace level. The maximum sorption capacity for Co(II) was found to be 0.203 mmol g−1 at pH 9.0. Sorbed Co(II) was completely eluted by 3.5 mL of 3 mol L−1 HCl and measured using flame atomic absorption spectrometer (FAAS). The structure of the extracted Co(II) complex was confirmed by single crystalX-raystructure and Fourier transform infrared (FTIR) spectroscopy. Thermo gravimetric analysis (TGA) of the chelated Co(II) complex revealed its stability at the optimum extraction temperature (55 °C). The method was reproducible with a relative standard deviation (RSD) of 0.6% (N = 10) with three sigma detection limit (N = 10) of 0.6 μg g−1. A pre-concentration factor, 94 was achieved. Interferences from Mn2+ and Cu2+ ions were eliminated by prior oxidation of Mn2+ by KIO4 to MnO4− and masking of Cu2+ with NH4SCN, respectively. A plausible mechanism for the selective extraction of Co(II) was attributed to the formation of a first order water insoluble inner–metallic complex as confirmed by the single crystalX-raystructure analysis. The developed method has been tested for trace level separation and estimation of cobalt in some certified reference materials. Analyses of some biological and environmental samples were performed. ISSN : 1385-8947 En ligne : http://www.sciencedirect.com/science/article/pii/S1385894711009910

Magnetic molecularly imprinted polymers based on attapulgite / Fe3O4 particles for the selective recognition of 2,4 - dichlorophenol / Jianming Pan in Chemical engineering journal, Vol. 174 N° 1 (Octobre 2011) 

Public ISBD [article]  in Chemical engineering journal > Vol. 174 N° 1 (Octobre 2011) . - pp.68-75 Titre : Magnetic molecularly imprinted polymers based on attapulgite / Fe3O4 particles for the selective recognition of 2,4 - dichlorophenol Type de document : texte imprimé Auteurs : Jianming Pan, Auteur ; Longcheng Xu, Auteur ; Jiangdong Dai, Auteur Année de publication : 2012 Article en page(s) : pp.68-75 Note générale : Génie chimique Langues : Anglais (eng) Mots-clés : Surface  imprinted  polymers  Selective  recognition  2,4-Dichlorophenol  Attapulgite  /Fe3O4  magnetic  particles  Magnetic  susceptibility Résumé : Via encapsulation of attapulgite/Fe3O4magneticparticles (ATP/Fe3O4), the magneticmolecularlyimprintedpolymers (MMIPs) were synthesized for the selective recognition of 2,4-dichlorophenol (2,4-DCP). MMIPs were characterized by X-ray diffraction (XRD), Fourier transform infrared (FT-IR) analysis, thermogravimetric analysis (TGA), vibrating sample magnetometer (VSM), transmission electron microscopy (TEM), nitrogen adsorption–desorption analysis and Raman spectroscopy. MMIPs were demonstrated claviform shape with an imprintedpolymer film (thickness of about 16 nm), and exhibited magnetic property (Ms = 5.67 emu g−1) and thermal stability. Batch mode adsorption studies were carried out to investigate the specific binding capacity, binding kinetics and recognition specificity. The Langmuir isotherm model was fitted to the equilibrium data better than the other models, and the monolayer adsorption capacity of MMIPs were 145.79 mg g−1 at 298 K. The kinetic properties of MMIPs were well described by the pseudo-second-order equation, initial adsorption rate and half-adsorption time. The selective recognition experiments demonstrated high affinity and selectivity towards 2,4-DCP over structurally related phenolic compounds. In addition, MMIPs could be regenerated, and their adsorption capacity in the fifth use was about 7.53% loss in 2,4-DCP solution. The MMIPs as-prepared were successfully applied to the separation of 2,4-DCP from environmental water samples. ISSN : 1385-8947 En ligne : http://www.sciencedirect.com/science/article/pii/S1385894711009922 [article] Magnetic molecularly imprinted polymers based on attapulgite / Fe3O4 particles for the selective recognition of 2,4 - dichlorophenol [texte imprimé] / Jianming Pan, Auteur ; Longcheng Xu, Auteur ; Jiangdong Dai, Auteur . - 2012 . - pp.68-75. Génie chimique Langues : Anglais (eng) in Chemical engineering journal > Vol. 174 N° 1 (Octobre 2011) . - pp.68-75 Mots-clés : Surface  imprinted  polymers  Selective  recognition  2,4-Dichlorophenol  Attapulgite  /Fe3O4  magnetic  particles  Magnetic  susceptibility Résumé : Via encapsulation of attapulgite/Fe3O4magneticparticles (ATP/Fe3O4), the magneticmolecularlyimprintedpolymers (MMIPs) were synthesized for the selective recognition of 2,4-dichlorophenol (2,4-DCP). MMIPs were characterized by X-ray diffraction (XRD), Fourier transform infrared (FT-IR) analysis, thermogravimetric analysis (TGA), vibrating sample magnetometer (VSM), transmission electron microscopy (TEM), nitrogen adsorption–desorption analysis and Raman spectroscopy. MMIPs were demonstrated claviform shape with an imprintedpolymer film (thickness of about 16 nm), and exhibited magnetic property (Ms = 5.67 emu g−1) and thermal stability. Batch mode adsorption studies were carried out to investigate the specific binding capacity, binding kinetics and recognition specificity. The Langmuir isotherm model was fitted to the equilibrium data better than the other models, and the monolayer adsorption capacity of MMIPs were 145.79 mg g−1 at 298 K. The kinetic properties of MMIPs were well described by the pseudo-second-order equation, initial adsorption rate and half-adsorption time. The selective recognition experiments demonstrated high affinity and selectivity towards 2,4-DCP over structurally related phenolic compounds. In addition, MMIPs could be regenerated, and their adsorption capacity in the fifth use was about 7.53% loss in 2,4-DCP solution. The MMIPs as-prepared were successfully applied to the separation of 2,4-DCP from environmental water samples. ISSN : 1385-8947 En ligne : http://www.sciencedirect.com/science/article/pii/S1385894711009922

Synthesis of aminopropyl triethoxysilane - functionalized silica and its application in speciation studies of vanadium(IV) and vanadium (V) / Asli Erdem in Chemical engineering journal, Vol. 174 N° 1 (Octobre 2011) 

Public ISBD [article]  in Chemical engineering journal > Vol. 174 N° 1 (Octobre 2011) . - pp.76-85 Titre : Synthesis of aminopropyl triethoxysilane - functionalized silica and its application in speciation studies of vanadium(IV) and vanadium (V) Type de document : texte imprimé Auteurs : Asli Erdem, Auteur ; Talal Shahwan, Auteur ; Ali Cagir, Auteur Année de publication : 2012 Article en page(s) : pp.76-85 Note générale : Génie chimique Langues : Anglais (eng) Mots-clés : Vanadium(IV)  Vanadium(V)Amine-functionalized  silica  Speciation  Inductively  coupled  plasma  mass  spectrometry Résumé : A solid phase extraction sorbent, aminopropyltriethoxysilane-functionalized silica was prepared and used for vanadiumspeciation prior to inductively coupled plasma mass spectrometric determination. The necessary sorption parameters such as sorption pH, reaction temperature, sorbent amount and sample volume were optimized. The sorption for V(V) and V(IV) under the optimized conditions was 98% (±1) and was lower than 10%, respectively. The sorption process was investigated both from a kinetic perspective and also in terms of Freundlich, Dubinin-Radushkevich and Langmuir isotherm models to characterize the uptake of vanadate ion by the functionalized silica. Desorption from the sorbent was realized with 0.5 mol L−1 thiourea prepared in 0.2 mol L−1 HCl. Among the possible interfering species tested, Te(IV), Se(IV), Se(VI) and Fe(III) showed interference effects with V(V) signal. The validity of the method was first checked via spike recovery experiments with four different types of water; namely ultra pure, bottled drinking, tap, and sea water for different concentrations of V(V). The percent recovery values changed between 87 and 108 for all water types. The accuracy of the proposed methodology was also checked by analyzing a standard reference material (NIST, SRM 1643e) and a good agreement was found between the determined and the certified value. The proposed methodology has also been shown to be applicable for the separate sorption of V(V) in the absence/presence of V(IV) and for the sorption of both V(IV) and V(V) in waters. The amount of V(IV) can then be determined from the difference. ISSN : 1385-8947 En ligne : http://www.sciencedirect.com/science/article/pii/S1385894711009958 [article] Synthesis of aminopropyl triethoxysilane - functionalized silica and its application in speciation studies of vanadium(IV) and vanadium (V) [texte imprimé] / Asli Erdem, Auteur ; Talal Shahwan, Auteur ; Ali Cagir, Auteur . - 2012 . - pp.76-85. Génie chimique Langues : Anglais (eng) in Chemical engineering journal > Vol. 174 N° 1 (Octobre 2011) . - pp.76-85 Mots-clés : Vanadium(IV)  Vanadium(V)Amine-functionalized  silica  Speciation  Inductively  coupled  plasma  mass  spectrometry Résumé : A solid phase extraction sorbent, aminopropyltriethoxysilane-functionalized silica was prepared and used for vanadiumspeciation prior to inductively coupled plasma mass spectrometric determination. The necessary sorption parameters such as sorption pH, reaction temperature, sorbent amount and sample volume were optimized. The sorption for V(V) and V(IV) under the optimized conditions was 98% (±1) and was lower than 10%, respectively. The sorption process was investigated both from a kinetic perspective and also in terms of Freundlich, Dubinin-Radushkevich and Langmuir isotherm models to characterize the uptake of vanadate ion by the functionalized silica. Desorption from the sorbent was realized with 0.5 mol L−1 thiourea prepared in 0.2 mol L−1 HCl. Among the possible interfering species tested, Te(IV), Se(IV), Se(VI) and Fe(III) showed interference effects with V(V) signal. The validity of the method was first checked via spike recovery experiments with four different types of water; namely ultra pure, bottled drinking, tap, and sea water for different concentrations of V(V). The percent recovery values changed between 87 and 108 for all water types. The accuracy of the proposed methodology was also checked by analyzing a standard reference material (NIST, SRM 1643e) and a good agreement was found between the determined and the certified value. The proposed methodology has also been shown to be applicable for the separate sorption of V(V) in the absence/presence of V(IV) and for the sorption of both V(IV) and V(V) in waters. The amount of V(IV) can then be determined from the difference. ISSN : 1385-8947 En ligne : http://www.sciencedirect.com/science/article/pii/S1385894711009958

The role of unburned carbon concentrates from fly ashes in the oxidation and retention of mercury / P. Abad-Valle in Chemical engineering journal, Vol. 174 N° 1 (Octobre 2011) 

Public ISBD [article]  in Chemical engineering journal > Vol. 174 N° 1 (Octobre 2011) . - pp.86-92 Titre : The role of unburned carbon concentrates from fly ashes in the oxidation and retention of mercury Type de document : texte imprimé Auteurs : P. Abad-Valle, Auteur ; M.A. Lopez-Anton, Auteur ; M. Diaz-Somoano, Auteur Année de publication : 2012 Article en page(s) : pp.86-92 Note générale : Génie chimique Langues : Anglais (eng) Mots-clés : Mercury  Fly  ash  Retention  Oxidation Résumé : During the combustion of coal in power plants Hg is released from the coal into the environment. Several technologies are under developed to reduce these emissions, but the need to implement new control systems will depend in part on the extent to which Hg can be captured in the flyash. Previous studies have demonstrated that flyashes may not only retain Hg species but also oxidize Hg0(g). This should be taken into consideration when developing technologies for Hg retention. The aim of this study is to acquire a better understanding of the interactions between Hg0(g) and flyashes and to clarify the effect of unburnedcarbon and the flue gas composition upon the retention and oxidation mechanisms. A series of retention, oxidation and desorption experiments were carried out using lab-scale reactors. All the results obtained indicate that the interaction between Hg and flyash is mainly chemical since the retention of Hg involves oxidation. Moreover, if the oxidation takes place in gas phase, condensation of oxidized mercury occurs. Carbonaceous matter is involved in most of the retention and oxidation mechanisms between Hg and flyash. The carbonconcentrates with the highest Hg retention capacity produce the highest Hg oxidation. The gas mixtures containing O2 + CO2 + SO2 + H2O were observed to increase Hg retention in the carbonconcentrates from flyashes. However, the presence of HCl in the mixtures may increase or decrease Hg capture. Heterogeneous oxidation was only significant in the flyash fractions enriched in unburnedcarbon. ISSN : 1385-8947 En ligne : http://www.sciencedirect.com/science/article/pii/S1385894711010114 [article] The role of unburned carbon concentrates from fly ashes in the oxidation and retention of mercury [texte imprimé] / P. Abad-Valle, Auteur ; M.A. Lopez-Anton, Auteur ; M. Diaz-Somoano, Auteur . - 2012 . - pp.86-92. Génie chimique Langues : Anglais (eng) in Chemical engineering journal > Vol. 174 N° 1 (Octobre 2011) . - pp.86-92 Mots-clés : Mercury  Fly  ash  Retention  Oxidation Résumé : During the combustion of coal in power plants Hg is released from the coal into the environment. Several technologies are under developed to reduce these emissions, but the need to implement new control systems will depend in part on the extent to which Hg can be captured in the flyash. Previous studies have demonstrated that flyashes may not only retain Hg species but also oxidize Hg0(g). This should be taken into consideration when developing technologies for Hg retention. The aim of this study is to acquire a better understanding of the interactions between Hg0(g) and flyashes and to clarify the effect of unburnedcarbon and the flue gas composition upon the retention and oxidation mechanisms. A series of retention, oxidation and desorption experiments were carried out using lab-scale reactors. All the results obtained indicate that the interaction between Hg and flyash is mainly chemical since the retention of Hg involves oxidation. Moreover, if the oxidation takes place in gas phase, condensation of oxidized mercury occurs. Carbonaceous matter is involved in most of the retention and oxidation mechanisms between Hg and flyash. The carbonconcentrates with the highest Hg retention capacity produce the highest Hg oxidation. The gas mixtures containing O2 + CO2 + SO2 + H2O were observed to increase Hg retention in the carbonconcentrates from flyashes. However, the presence of HCl in the mixtures may increase or decrease Hg capture. Heterogeneous oxidation was only significant in the flyash fractions enriched in unburnedcarbon. ISSN : 1385-8947 En ligne : http://www.sciencedirect.com/science/article/pii/S1385894711010114

Particle deposition and detachment in capillary sphere packings / Norbert Riefler in Chemical engineering journal, Vol. 174 N° 1 (Octobre 2011) 

Public ISBD [article]  in Chemical engineering journal > Vol. 174 N° 1 (Octobre 2011) . - pp.93-101 Titre : Particle deposition and detachment in capillary sphere packings Type de document : texte imprimé Auteurs : Norbert Riefler, Auteur ; Michael Heiland, Auteur ; Anja Waske, Auteur Année de publication : 2012 Article en page(s) : pp.93-101 Note générale : Génie chimique Langues : Anglais (eng) Mots-clés : Porous  body  Sphere  packings  Computational  fluid  dynamic  CFD  Filtration  Particle  deposition  +  detachment Résumé : Flow simulations in a random spherepacking are used to investigate particulate filtration processes. The local wall shear stress is used to calculate an angular dependent distribution for particledetachment. Simulations of particledeposition by interceptions yield the angular dependent number of impacts. The results from particledetachment calculations and the interception analysis are combined to estimate local particledeposition rates, employing probabilities for detachment and impact. Comparison with X-ray computer tomography of deposited particles within a spherepacking shows good agreement. Therefore, the presented simulation procedure can be used for the design of, e.g., particle filtration apparatus. ISSN : 1385-8947 En ligne : http://www.sciencedirect.com/science/article/pii/S1385894711010138 [article] Particle deposition and detachment in capillary sphere packings [texte imprimé] / Norbert Riefler, Auteur ; Michael Heiland, Auteur ; Anja Waske, Auteur . - 2012 . - pp.93-101. Génie chimique Langues : Anglais (eng) in Chemical engineering journal > Vol. 174 N° 1 (Octobre 2011) . - pp.93-101 Mots-clés : Porous  body  Sphere  packings  Computational  fluid  dynamic  CFD  Filtration  Particle  deposition  +  detachment Résumé : Flow simulations in a random spherepacking are used to investigate particulate filtration processes. The local wall shear stress is used to calculate an angular dependent distribution for particledetachment. Simulations of particledeposition by interceptions yield the angular dependent number of impacts. The results from particledetachment calculations and the interception analysis are combined to estimate local particledeposition rates, employing probabilities for detachment and impact. Comparison with X-ray computer tomography of deposited particles within a spherepacking shows good agreement. Therefore, the presented simulation procedure can be used for the design of, e.g., particle filtration apparatus. ISSN : 1385-8947 En ligne : http://www.sciencedirect.com/science/article/pii/S1385894711010138

Drinking water treatment in a gravimetric flow system with TiO2 coated membranes / Rosangela Bergamasco in Chemical engineering journal, Vol. 174 N° 1 (Octobre 2011) 

Public ISBD [article]  in Chemical engineering journal > Vol. 174 N° 1 (Octobre 2011) . - pp.102-109 Titre : Drinking water treatment in a gravimetric flow system with TiO2 coated membranes Type de document : texte imprimé Auteurs : Rosangela Bergamasco, Auteur ; Flávia Vieira Silva, Auteur ; Flávia Sayuri Arakawa, Auteur Année de publication : 2012 Article en page(s) : pp.102-109 Note générale : Génie chimique Langues : Anglais (eng) Mots-clés : Drinking  water  Membrane  modification  TiO2  film  Membrane  fouling Résumé : This paper presents filtration results for drinkingwatertreatment obtained with a commercial cellulose acetate membrane of 0.45 μm pore diameter, with and without TiO2 coating. The deposition of titanium dioxide thin films onto membrane surface was made by pulsed-frequency d.c. reactive magnetron sputtering at room temperature from a high purity Ti target in Ar/O2/N2 atmosphere, at different conditions for cathode current and for deposition time. The proposed membranes were used in a filtration system driven by gravitation without the requirement of energy supply. The obtained results showed that the proposed system is able to remove color and turbidity from raw water. Besides, the modified membrane presented better results than the neat one regarding to membrane fouling and chlorine removal. ISSN : 1385-8947 En ligne : http://www.sciencedirect.com/science/article/pii/S138589471101014X [article] Drinking water treatment in a gravimetric flow system with TiO2 coated membranes [texte imprimé] / Rosangela Bergamasco, Auteur ; Flávia Vieira Silva, Auteur ; Flávia Sayuri Arakawa, Auteur . - 2012 . - pp.102-109. Génie chimique Langues : Anglais (eng) in Chemical engineering journal > Vol. 174 N° 1 (Octobre 2011) . - pp.102-109 Mots-clés : Drinking  water  Membrane  modification  TiO2  film  Membrane  fouling Résumé : This paper presents filtration results for drinkingwatertreatment obtained with a commercial cellulose acetate membrane of 0.45 μm pore diameter, with and without TiO2 coating. The deposition of titanium dioxide thin films onto membrane surface was made by pulsed-frequency d.c. reactive magnetron sputtering at room temperature from a high purity Ti target in Ar/O2/N2 atmosphere, at different conditions for cathode current and for deposition time. The proposed membranes were used in a filtration system driven by gravitation without the requirement of energy supply. The obtained results showed that the proposed system is able to remove color and turbidity from raw water. Besides, the modified membrane presented better results than the neat one regarding to membrane fouling and chlorine removal. ISSN : 1385-8947 En ligne : http://www.sciencedirect.com/science/article/pii/S138589471101014X

Mass transport modeling of Cs (I) through hollowfiber supported liquid membrane containing calix - [4] - bis(2,3 - naptho) - crown - 6 as the mobile carrier / P. Kandwal in Chemical engineering journal, Vol. 174 N° 1 (Octobre 2011) 

Public ISBD [article]  in Chemical engineering journal > Vol. 174 N° 1 (Octobre 2011) . - pp.110-116 Titre : Mass transport modeling of Cs (I) through hollowfiber supported liquid membrane containing calix - [4] - bis(2,3 - naptho) - crown - 6 as the mobile carrier Type de document : texte imprimé Auteurs : P. Kandwal, Auteur ; S. Dixit, Auteur ; S. Mukhopadhyay, Auteur Année de publication : 2012 Article en page(s) : pp.110-116 Note générale : Génie chimique Langues : Anglais (eng) Mots-clés : Hollow  fiber  Liquid  membrane  Cesium  Calix-crown  Waste  management Résumé : A mathematical model is developed for the transport of cesium through hollowfibersupportedliquidmembrane (HFSLM) containingcalix-[4]-bis(2,3-naptho)-crown-6 (CNC) as the carrier extractant in NPOE and n-dodecane mixture as diluent. The model is developed on the principle of facilitated diffusional transport mechanism with laminar flow inside the tubular region in the fiber with all the flow rate conditions. It predicts the rate of transport of cesium from feed solution under various experimental conditions and system compositions. Simultaneously, experiments were performed taking varying concentrations of cesium nitrate in 3 M HNO3 as the feed solution and distilled water as the strip and the cesium transport rates were measured. Both the results were plotted and a good level of agreement is seen between predicted and experimental data points. Similar studies were carried out as a function of carrier extractant concentration and varying feed and strip flow rates. Reasonable agreement between the experimental and predicted data suggested validity of the developed model. ISSN : 1385-8947 En ligne : http://www.sciencedirect.com/science/article/pii/S1385894711010151 [article] Mass transport modeling of Cs (I) through hollowfiber supported liquid membrane containing calix - [4] - bis(2,3 - naptho) - crown - 6 as the mobile carrier [texte imprimé] / P. Kandwal, Auteur ; S. Dixit, Auteur ; S. Mukhopadhyay, Auteur . - 2012 . - pp.110-116. Génie chimique Langues : Anglais (eng) in Chemical engineering journal > Vol. 174 N° 1 (Octobre 2011) . - pp.110-116 Mots-clés : Hollow  fiber  Liquid  membrane  Cesium  Calix-crown  Waste  management Résumé : A mathematical model is developed for the transport of cesium through hollowfibersupportedliquidmembrane (HFSLM) containingcalix-[4]-bis(2,3-naptho)-crown-6 (CNC) as the carrier extractant in NPOE and n-dodecane mixture as diluent. The model is developed on the principle of facilitated diffusional transport mechanism with laminar flow inside the tubular region in the fiber with all the flow rate conditions. It predicts the rate of transport of cesium from feed solution under various experimental conditions and system compositions. Simultaneously, experiments were performed taking varying concentrations of cesium nitrate in 3 M HNO3 as the feed solution and distilled water as the strip and the cesium transport rates were measured. Both the results were plotted and a good level of agreement is seen between predicted and experimental data points. Similar studies were carried out as a function of carrier extractant concentration and varying feed and strip flow rates. Reasonable agreement between the experimental and predicted data suggested validity of the developed model. ISSN : 1385-8947 En ligne : http://www.sciencedirect.com/science/article/pii/S1385894711010151

NaOH - activated carbon of high surface area produced from coconut shell / André L. Cazetta in Chemical engineering journal, Vol. 174 N° 1 (Octobre 2011) 

Public ISBD [article]  in Chemical engineering journal > Vol. 174 N° 1 (Octobre 2011) . - pp.117-125 Titre : NaOH - activated carbon of high surface area produced from coconut shell : Kinetics and equilibrium studies from the methylene blue adsorption Type de document : texte imprimé Auteurs : André L. Cazetta, Auteur ; Alexandro M.M. Vargas, Auteur ; Eurica M. Nogami, Auteur Année de publication : 2012 Article en page(s) : pp.117-125 Note générale : Génie chimique Langues : Anglais (eng) Mots-clés : NaOH-activated  carbon  Coconut  shell  Methylene  blue  Adsorption Résumé : Activatedcarbons (ACs) of coconutshellproduced by NaOH activation at impregnation ratios of NaOH:char (w/w) equal to 1:1 (AC-1), 2:1 (AC-2) and 3:1 (AC-3) were prepared. The properties of these carbons, including BET surfacearea, pore volume, pore size distribution, and pore diameter, were characterized from N2 adsorption isotherms. It was found that the ACs are essentially microporous and that the BET surfacearea was in order of 783 m2 g−1 for AC-1, 1842 m2 g−1 for AC-2, and 2825 m2 g−1 for AC-3. Scanning electron microscopy images showed a high pore development while Boehm method and Fourier-transform infrared spectroscopy spectra indicated the presence of acid functional groups which was confirmed by pH drift method. The adsorption equilibrium and kinetics of methylene blue (MB) onto AC-3 were carried out. Experimental data were fitted to the four isotherm models (Langmuir, Freundlich, Toth and Redlich–Peterson), and was found that Langmuir model presented the best fit, showing maximum monolayer adsorption capacity of 916 mg g−1. The kinetic studies showed that experimental data follow pseudo-second-order model. The mechanism of the adsorption process was described from the intraparticle diffusion model. The AC-3 has a highsurfacearea and showed to be an efficient adsorbent for removal of MB from aqueous solutions. ISSN : 1385-8947 En ligne : http://www.sciencedirect.com/science/article/pii/S1385894711010163 [article] NaOH - activated carbon of high surface area produced from coconut shell : Kinetics and equilibrium studies from the methylene blue adsorption [texte imprimé] / André L. Cazetta, Auteur ; Alexandro M.M. Vargas, Auteur ; Eurica M. Nogami, Auteur . - 2012 . - pp.117-125. Génie chimique Langues : Anglais (eng) in Chemical engineering journal > Vol. 174 N° 1 (Octobre 2011) . - pp.117-125 Mots-clés : NaOH-activated  carbon  Coconut  shell  Methylene  blue  Adsorption Résumé : Activatedcarbons (ACs) of coconutshellproduced by NaOH activation at impregnation ratios of NaOH:char (w/w) equal to 1:1 (AC-1), 2:1 (AC-2) and 3:1 (AC-3) were prepared. The properties of these carbons, including BET surfacearea, pore volume, pore size distribution, and pore diameter, were characterized from N2 adsorption isotherms. It was found that the ACs are essentially microporous and that the BET surfacearea was in order of 783 m2 g−1 for AC-1, 1842 m2 g−1 for AC-2, and 2825 m2 g−1 for AC-3. Scanning electron microscopy images showed a high pore development while Boehm method and Fourier-transform infrared spectroscopy spectra indicated the presence of acid functional groups which was confirmed by pH drift method. The adsorption equilibrium and kinetics of methylene blue (MB) onto AC-3 were carried out. Experimental data were fitted to the four isotherm models (Langmuir, Freundlich, Toth and Redlich–Peterson), and was found that Langmuir model presented the best fit, showing maximum monolayer adsorption capacity of 916 mg g−1. The kinetic studies showed that experimental data follow pseudo-second-order model. The mechanism of the adsorption process was described from the intraparticle diffusion model. The AC-3 has a highsurfacearea and showed to be an efficient adsorbent for removal of MB from aqueous solutions. ISSN : 1385-8947 En ligne : http://www.sciencedirect.com/science/article/pii/S1385894711010163

Removal of cobalt from aqueous solution by magnetic multiwalled carbon nanotube/iron oxide composites / Qi Wang in Chemical engineering journal, Vol. 174 N° 1 (Octobre 2011) 

Public ISBD [article]  in Chemical engineering journal > Vol. 174 N° 1 (Octobre 2011) . - pp.126–133 Titre : Removal of cobalt from aqueous solution by magnetic multiwalled carbon nanotube/iron oxide composites Type de document : texte imprimé Auteurs : Qi Wang, Auteur ; Jiaxing Li, Auteur ; Changlun Chen, Auteur Année de publication : 2012 Article en page(s) : pp.126–133 Note générale : Génie chimique Langues : Anglais (eng) Mots-clés : Co(II)  Magnetic  MWCNT/IO  composites  Humic  substances  Removal Résumé : The effects of contact time, pH, ionic strength, foreign ions, temperature, humic substances (HSs), and the addition sequences of Co(II)/HSs on Co(II) sorption on magneticmultiwalled carbon nanotube/iron oxide composites (magnetic MWCNT/IO composites) were investigated under ambient conditions. The results indicated that Co(II) sorption on the magnetic MWCNT/IO composites increased with increasing pH. The ionic strength and foreign ion dependent of Co(II) sorption suggested that ion exchange and outer-sphere surface complexation were the main sorption mechanism at low pH, whereas the ionic strength and foreign ion independent of Co(II) sorption at high pH values indicated that inner-sphere surface complexation was predominant sorption mechanism. The Langmuir model fitted Co(II) sorption isotherms better than the Freundlich model. The thermodynamic data calculated from the temperature dependent sorption isotherms suggested that Co(II) sorption on the magnetic MWCNT/IO composites was a spontaneous and endothermic process. The removal of Co(II) by the magnetic MWCNT/IO composites was affected evidently by the presence of HSs and by the addition sequences of Co(II)/HSs. This study highlights the interactions between Co(II) and HSs to determine the mutual effects of inorganic and organic matters on the removal of metal ions in environmental pollution management. ISSN : 1385-8947 En ligne : http://www.sciencedirect.com/science/article/pii/S1385894711010175 [article] Removal of cobalt from aqueous solution by magnetic multiwalled carbon nanotube/iron oxide composites [texte imprimé] / Qi Wang, Auteur ; Jiaxing Li, Auteur ; Changlun Chen, Auteur . - 2012 . - pp.126–133. Génie chimique Langues : Anglais (eng) in Chemical engineering journal > Vol. 174 N° 1 (Octobre 2011) . - pp.126–133 Mots-clés : Co(II)  Magnetic  MWCNT/IO  composites  Humic  substances  Removal Résumé : The effects of contact time, pH, ionic strength, foreign ions, temperature, humic substances (HSs), and the addition sequences of Co(II)/HSs on Co(II) sorption on magneticmultiwalled carbon nanotube/iron oxide composites (magnetic MWCNT/IO composites) were investigated under ambient conditions. The results indicated that Co(II) sorption on the magnetic MWCNT/IO composites increased with increasing pH. The ionic strength and foreign ion dependent of Co(II) sorption suggested that ion exchange and outer-sphere surface complexation were the main sorption mechanism at low pH, whereas the ionic strength and foreign ion independent of Co(II) sorption at high pH values indicated that inner-sphere surface complexation was predominant sorption mechanism. The Langmuir model fitted Co(II) sorption isotherms better than the Freundlich model. The thermodynamic data calculated from the temperature dependent sorption isotherms suggested that Co(II) sorption on the magnetic MWCNT/IO composites was a spontaneous and endothermic process. The removal of Co(II) by the magnetic MWCNT/IO composites was affected evidently by the presence of HSs and by the addition sequences of Co(II)/HSs. This study highlights the interactions between Co(II) and HSs to determine the mutual effects of inorganic and organic matters on the removal of metal ions in environmental pollution management. ISSN : 1385-8947 En ligne : http://www.sciencedirect.com/science/article/pii/S1385894711010175

Improved mineralization by combined advanced oxidation processes / A. Rey in Chemical engineering journal, Vol. 174 N° 1 (Octobre 2011) 

Public ISBD [article]  in Chemical engineering journal > Vol. 174 N° 1 (Octobre 2011) . - pp. 134–142 Titre : Improved mineralization by combined advanced oxidation processes Type de document : texte imprimé Auteurs : A. Rey, Auteur ; J. Carbajo, Auteur ; C. Adán, Auteur Année de publication : 2012 Article en page(s) : pp. 134–142 Note générale : Génie chimique Langues : Anglais (eng) Mots-clés : CWPO  Photocatalysis  Photo-Fenton  Activated  carbon  Iron  Titania Résumé : Different single treatments and a combined process based on two advanced oxidation processes, catalytic wet peroxide oxidation and photocatalysis, have been tested for the purpose of achieving complete mineralization using phenol as target compound at medium-range concentration (200 mg L−1). The heterogenous catalysts that were used were a home-made activated carbon-supported iron catalyst (FeCN), and the commercial Aeroxide titania P25. An important improvement in the rate and percentage of TOC removal was achieved by combining both catalysts in a hybrid process based on a mixture of FeCN and TiO2 P25 (50:50 wt.%) in the same photoassisted reactor in ambient conditions. TOC evolution has been modelled for all the treatments for comparative purposes. The hybrid process allowed a highly efficient use of hydrogen peroxide with the almost complete oxidation of phenol to CO2 and H2O by using the theoretical stoichiometric amount of H2O2. Among the different advantages of this hybrid process is the rapid and effective degradation of the aromatic compounds adsorbed onto the Fe/CN catalyst surface as a consequence of synergistic effect of the two catalysts in the presence of irradiation light in ambient conditions, achieving a higher degree of mineralization of short-chain organic acids that are resistant and refractory to CWPO treatment. Finally, the stability and durability of this catalytic mixture (FeCN + titania P25) in hybrid mode have been examined through four consecutive cycles. A constant organic matter removal was observed during the last three consecutive cycles in which 90% of total organic carbon conversion was achieved. ISSN : 1385-8947 En ligne : http://www.sciencedirect.com/science/article/pii/S1385894711010199 [article] Improved mineralization by combined advanced oxidation processes [texte imprimé] / A. Rey, Auteur ; J. Carbajo, Auteur ; C. Adán, Auteur . - 2012 . - pp. 134–142. Génie chimique Langues : Anglais (eng) in Chemical engineering journal > Vol. 174 N° 1 (Octobre 2011) . - pp. 134–142 Mots-clés : CWPO  Photocatalysis  Photo-Fenton  Activated  carbon  Iron  Titania Résumé : Different single treatments and a combined process based on two advanced oxidation processes, catalytic wet peroxide oxidation and photocatalysis, have been tested for the purpose of achieving complete mineralization using phenol as target compound at medium-range concentration (200 mg L−1). The heterogenous catalysts that were used were a home-made activated carbon-supported iron catalyst (FeCN), and the commercial Aeroxide titania P25. An important improvement in the rate and percentage of TOC removal was achieved by combining both catalysts in a hybrid process based on a mixture of FeCN and TiO2 P25 (50:50 wt.%) in the same photoassisted reactor in ambient conditions. TOC evolution has been modelled for all the treatments for comparative purposes. The hybrid process allowed a highly efficient use of hydrogen peroxide with the almost complete oxidation of phenol to CO2 and H2O by using the theoretical stoichiometric amount of H2O2. Among the different advantages of this hybrid process is the rapid and effective degradation of the aromatic compounds adsorbed onto the Fe/CN catalyst surface as a consequence of synergistic effect of the two catalysts in the presence of irradiation light in ambient conditions, achieving a higher degree of mineralization of short-chain organic acids that are resistant and refractory to CWPO treatment. Finally, the stability and durability of this catalytic mixture (FeCN + titania P25) in hybrid mode have been examined through four consecutive cycles. A constant organic matter removal was observed during the last three consecutive cycles in which 90% of total organic carbon conversion was achieved. ISSN : 1385-8947 En ligne : http://www.sciencedirect.com/science/article/pii/S1385894711010199

Removal capacity and adsorption mechanism of heat-treated palygorskite clay for methylene blue / Hao Chen in Chemical engineering journal, Vol. 174 N° 1 (Octobre 2011) 

Public ISBD [article]  in Chemical engineering journal > Vol. 174 N° 1 (Octobre 2011) . - pp.143–150 Titre : Removal capacity and adsorption mechanism of heat-treated palygorskite clay for methylene blue Type de document : texte imprimé Auteurs : Hao Chen, Auteur ; Jie Zhao, Auteur ; Aiguo Zhong, Auteur Année de publication : 2012 Article en page(s) : pp.143–150 Note générale : Génie chimique Langues : Anglais (eng) Mots-clés : Adsorption  Heat-treated  palygorskite  Methylene  blue  Dissolved  ions  Mechanism Résumé : In this work, palygorskite clay was activated by heat treatment method and its capacity for the removal of a typical cationic dye, methylene blue, was studied. The activated samples were characterized by XRD and BET techniques. The physical quantities including the cation exchange capacity (CEC) of the activated samples, the variation of pH during the adsorption process and the concentration of metal ions in the supernatant were also measured. The results show that the adsorption capacity of the heat-treated sample increases with temperature and reaches the maximum at 700 °C, and then decreases with further increasing temperature. In general, with the increasing calcined temperature, the variation trend of the adsorption capacity of activated samples for dye is accordant with that of CEC. The results of the metal ions leached from the adsorbent demonstrate the leaching amount of divalent ions (Mg2+, Ca2+) in all samples are significantly higher than that of univalent (Na+, K+) and trivalent ions (Fe3+, Al3+). In addition, the changing tendency of leaching amount of divalent ions with the increasing temperature is consistent with that of adsorption capacity of the heat-treated samples whether the dye solution is acidic, neutral or alkaline. The leaching of divalent ions should be the main factor affecting the adsorption capacity of heat-activated palygorskite for methylene blue. ISSN : 1385-8947 En ligne : http://www.sciencedirect.com/science/article/pii/S1385894711010205 [article] Removal capacity and adsorption mechanism of heat-treated palygorskite clay for methylene blue [texte imprimé] / Hao Chen, Auteur ; Jie Zhao, Auteur ; Aiguo Zhong, Auteur . - 2012 . - pp.143–150. Génie chimique Langues : Anglais (eng) in Chemical engineering journal > Vol. 174 N° 1 (Octobre 2011) . - pp.143–150 Mots-clés : Adsorption  Heat-treated  palygorskite  Methylene  blue  Dissolved  ions  Mechanism Résumé : In this work, palygorskite clay was activated by heat treatment method and its capacity for the removal of a typical cationic dye, methylene blue, was studied. The activated samples were characterized by XRD and BET techniques. The physical quantities including the cation exchange capacity (CEC) of the activated samples, the variation of pH during the adsorption process and the concentration of metal ions in the supernatant were also measured. The results show that the adsorption capacity of the heat-treated sample increases with temperature and reaches the maximum at 700 °C, and then decreases with further increasing temperature. In general, with the increasing calcined temperature, the variation trend of the adsorption capacity of activated samples for dye is accordant with that of CEC. The results of the metal ions leached from the adsorbent demonstrate the leaching amount of divalent ions (Mg2+, Ca2+) in all samples are significantly higher than that of univalent (Na+, K+) and trivalent ions (Fe3+, Al3+). In addition, the changing tendency of leaching amount of divalent ions with the increasing temperature is consistent with that of adsorption capacity of the heat-treated samples whether the dye solution is acidic, neutral or alkaline. The leaching of divalent ions should be the main factor affecting the adsorption capacity of heat-activated palygorskite for methylene blue. ISSN : 1385-8947 En ligne : http://www.sciencedirect.com/science/article/pii/S1385894711010205

Biosorptive uptake of Cr(VI) from aqueous solutions by Parthenium hysterophorous weed / V. Venugopal in Chemical engineering journal, Vol. 174 N° 1 (Octobre 2011) 

Public ISBD [article]  in Chemical engineering journal > Vol. 174 N° 1 (Octobre 2011) . - pp.151-158 Titre : Biosorptive uptake of Cr(VI) from aqueous solutions by Parthenium hysterophorous weed : Equilibrium, kinetics and thermodynamic studies Type de document : texte imprimé Auteurs : V. Venugopal, Auteur ; Kaustubha Mohanty, Auteur Année de publication : 2012 Article en page(s) : pp.151-158 Note générale : Génie chimique Langues : Anglais (eng) Mots-clés : Adsorption  Cr(VI)  Kinetics  Thermodynamics  Wastewater  treatment  Waste  biomass Résumé : In the present work the potential of Parthenium (P. hysterophorus L.) weed to remove Cr(VI) ions from aqueous solution was reported. FTIR was used to study the functional groups present on the surface of the biosorbent and it was found that carboxyl, amine and alkane groups were the leading Cr binding groups. Effect of various parameters such as contact time, temperature, pH, agitation speed, biosorbent dose and initial Cr(VI) concentration on the biosorption was investigated by batch process. The equilibrium data was well described by both Langmuir and Freundlich isotherms. The biosorption capacity of Parthenium weed for Cr(VI) was found. Highlights: A new biosorbent was developed from waste weed of Parthenium. Biosorbent developed was low-cost and renewable in nature. It was used successfully for removal of Cr(VI) ions from aqueous solutions. Maximum adsorption was found to ne 24.5mg/g at optimized conditions. The developed biosorbent has the potential of removing Cr(VI) in an environmentally friendly process. ISSN : 1385-8947 En ligne : http://scienceindex.com/stories/1823781/Biosorptive_uptake_of_CrVI_from_aqueous_ [...] [article] Biosorptive uptake of Cr(VI) from aqueous solutions by Parthenium hysterophorous weed : Equilibrium, kinetics and thermodynamic studies [texte imprimé] / V. Venugopal, Auteur ; Kaustubha Mohanty, Auteur . - 2012 . - pp.151-158. Génie chimique Langues : Anglais (eng) in Chemical engineering journal > Vol. 174 N° 1 (Octobre 2011) . - pp.151-158 Mots-clés : Adsorption  Cr(VI)  Kinetics  Thermodynamics  Wastewater  treatment  Waste  biomass Résumé : In the present work the potential of Parthenium (P. hysterophorus L.) weed to remove Cr(VI) ions from aqueous solution was reported. FTIR was used to study the functional groups present on the surface of the biosorbent and it was found that carboxyl, amine and alkane groups were the leading Cr binding groups. Effect of various parameters such as contact time, temperature, pH, agitation speed, biosorbent dose and initial Cr(VI) concentration on the biosorption was investigated by batch process. The equilibrium data was well described by both Langmuir and Freundlich isotherms. The biosorption capacity of Parthenium weed for Cr(VI) was found. Highlights: A new biosorbent was developed from waste weed of Parthenium. Biosorbent developed was low-cost and renewable in nature. It was used successfully for removal of Cr(VI) ions from aqueous solutions. Maximum adsorption was found to ne 24.5mg/g at optimized conditions. The developed biosorbent has the potential of removing Cr(VI) in an environmentally friendly process. ISSN : 1385-8947 En ligne : http://scienceindex.com/stories/1823781/Biosorptive_uptake_of_CrVI_from_aqueous_ [...]

Bioaugmentation and functional partitioning in a zero valent iron - anaerobic reactor for sulfate - containing wastewater treatment / Jingxin Zhang in Chemical engineering journal, Vol. 174 N° 1 (Octobre 2011) 

Public ISBD [article]  in Chemical engineering journal > Vol. 174 N° 1 (Octobre 2011) . - pp.159-165 Titre : Bioaugmentation and functional partitioning in a zero valent iron - anaerobic reactor for sulfate - containing wastewater treatment Type de document : texte imprimé Auteurs : Jingxin Zhang, Auteur ; Yaobin Zhang, Auteur ; Xie Quan, Auteur Année de publication : 2012 Article en page(s) : pp.159-165 Note générale : Génie chimique Langues : Anglais (eng) Mots-clés : Sulfate-containing  wastewater  Zero-valent  iron  Anaerobic  Two-stage  anaerobic  reactor Résumé : Sulfate inhibits anaerobic digestion because it stimulates sulfate reduction bacteria (SRB) to compete with methanogens for electron utilization and sulfide produced has toxicity to microorganism. Considering that zero-valent iron (ZVI) is expected to abbreviate the above negative effects due to its reductibility, a ZVI bed was packed into an anaerobic (ZVI-anaerobic) reactor (R1) for improvement of sulfate-containing wastewater treatment. The results showed that R1 could maintain high COD removal performance (87.4%) at sulfate concentration (1100 mg/L), significantly higher than a control reactor without ZVI (R2, 58.2%). In R1, 95% of the sulfate was reduced at the bottom, which decreased its effects on methanogens in the upper portion. In consequence, the COD removal in the upper portion of R1 (39.4%) was significantly higher than that of R2 (11.4%). Fluorescence in situ hybridization showed that the fractions of methanogens and SRB presented highest in the upper portion and the bottom of R1 respectively. PCR–DGGE analysis indicated that the microbial communities between the bottom and the upper part of R1 were different and diversity by the addition of ZVI bed. The functionalized partitioning of microbial activities in R1, i.e., most sulfate reduction occurring in the bottom and more efficient methanogenesis occurring in the upper, which was similar to a two-stage anaerobic reactor for sulfate-containing wastewater treatment, made this ZVI-anaerobic reactor displayed well. ISSN : 1385-8947 En ligne : http://www.sciencedirect.com/science/article/pii/S1385894711010278 [article] Bioaugmentation and functional partitioning in a zero valent iron - anaerobic reactor for sulfate - containing wastewater treatment [texte imprimé] / Jingxin Zhang, Auteur ; Yaobin Zhang, Auteur ; Xie Quan, Auteur . - 2012 . - pp.159-165. Génie chimique Langues : Anglais (eng) in Chemical engineering journal > Vol. 174 N° 1 (Octobre 2011) . - pp.159-165 Mots-clés : Sulfate-containing  wastewater  Zero-valent  iron  Anaerobic  Two-stage  anaerobic  reactor Résumé : Sulfate inhibits anaerobic digestion because it stimulates sulfate reduction bacteria (SRB) to compete with methanogens for electron utilization and sulfide produced has toxicity to microorganism. Considering that zero-valent iron (ZVI) is expected to abbreviate the above negative effects due to its reductibility, a ZVI bed was packed into an anaerobic (ZVI-anaerobic) reactor (R1) for improvement of sulfate-containing wastewater treatment. The results showed that R1 could maintain high COD removal performance (87.4%) at sulfate concentration (1100 mg/L), significantly higher than a control reactor without ZVI (R2, 58.2%). In R1, 95% of the sulfate was reduced at the bottom, which decreased its effects on methanogens in the upper portion. In consequence, the COD removal in the upper portion of R1 (39.4%) was significantly higher than that of R2 (11.4%). Fluorescence in situ hybridization showed that the fractions of methanogens and SRB presented highest in the upper portion and the bottom of R1 respectively. PCR–DGGE analysis indicated that the microbial communities between the bottom and the upper part of R1 were different and diversity by the addition of ZVI bed. The functionalized partitioning of microbial activities in R1, i.e., most sulfate reduction occurring in the bottom and more efficient methanogenesis occurring in the upper, which was similar to a two-stage anaerobic reactor for sulfate-containing wastewater treatment, made this ZVI-anaerobic reactor displayed well. ISSN : 1385-8947 En ligne : http://www.sciencedirect.com/science/article/pii/S1385894711010278

Thermo-oxidative pretreatment of municipal waste activated sludge for volatile sulfur compounds removal and enhanced anaerobic digestion / Bipro Ranjan Dhar in Chemical engineering journal, Vol. 174 N° 1 (Octobre 2011) 

Public ISBD [article]  in Chemical engineering journal > Vol. 174 N° 1 (Octobre 2011) . - pp. 166–174 Titre : Thermo-oxidative pretreatment of municipal waste activated sludge for volatile sulfur compounds removal and enhanced anaerobic digestion Type de document : texte imprimé Auteurs : Bipro Ranjan Dhar, Auteur ; Elsayed Elbeshbishy, Auteur ; Hisham Hafez, Auteur Année de publication : 2012 Article en page(s) : pp. 166–174 Note générale : Génie chimique Langues : Anglais (eng) Mots-clés : Anaerobic  digestion  Hydrogen  sulfide  Waste  activated  sludge  Thermo-oxidative  pretreatment  Volatile  sulfur  compounds Résumé : Thermo-oxidative pretreatment of municipal waste activated sludge was conducted using thermal pretreatment at 60 °C in presence of 0.6 mg H2O2 + 1.5 mg FeCl2/mg S2− as oxidants with the objective of achieving sludge disintegration for enhancing anaerobic digestion as well as to remove volatile sulfur compounds generation potential in biogas in continuous anaerobic digestion. For the pretreated feed digester, the hydrogen sulfide (H2S) and dimethyl sulfide (DMS) concentrations in biogas significantly decreased by an average of 75%, and 40%, respectively, while methanethiol (MT) removal efficiency was statistically insignificant compared to the control digester. Compared to the control, overall TSS and VSS removal efficiency were 10% and 11% higher for the pretreated feed digester operated at 10 days solid residence time (SRT), and methane production rate (L CH4/Day) increased by ∼20%. The simulation results using BioWin® suggest that the thermo-oxidative pretreatment has significantly increased the hydrolysis rate by 30% with higher methane production rate compared to the control digester. ISSN : 1385-8947 En ligne : http://www.sciencedirect.com/science/article/pii/S138589471101028X [article] Thermo-oxidative pretreatment of municipal waste activated sludge for volatile sulfur compounds removal and enhanced anaerobic digestion [texte imprimé] / Bipro Ranjan Dhar, Auteur ; Elsayed Elbeshbishy, Auteur ; Hisham Hafez, Auteur . - 2012 . - pp. 166–174. Génie chimique Langues : Anglais (eng) in Chemical engineering journal > Vol. 174 N° 1 (Octobre 2011) . - pp. 166–174 Mots-clés : Anaerobic  digestion  Hydrogen  sulfide  Waste  activated  sludge  Thermo-oxidative  pretreatment  Volatile  sulfur  compounds Résumé : Thermo-oxidative pretreatment of municipal waste activated sludge was conducted using thermal pretreatment at 60 °C in presence of 0.6 mg H2O2 + 1.5 mg FeCl2/mg S2− as oxidants with the objective of achieving sludge disintegration for enhancing anaerobic digestion as well as to remove volatile sulfur compounds generation potential in biogas in continuous anaerobic digestion. For the pretreated feed digester, the hydrogen sulfide (H2S) and dimethyl sulfide (DMS) concentrations in biogas significantly decreased by an average of 75%, and 40%, respectively, while methanethiol (MT) removal efficiency was statistically insignificant compared to the control digester. Compared to the control, overall TSS and VSS removal efficiency were 10% and 11% higher for the pretreated feed digester operated at 10 days solid residence time (SRT), and methane production rate (L CH4/Day) increased by ∼20%. The simulation results using BioWin® suggest that the thermo-oxidative pretreatment has significantly increased the hydrolysis rate by 30% with higher methane production rate compared to the control digester. ISSN : 1385-8947 En ligne : http://www.sciencedirect.com/science/article/pii/S138589471101028X

A preliminary study of simultaneous lime treatment and dry digestion of smooth cordgrass for biogas production / Yuegan Liang in Chemical engineering journal, Vol. 174 N° 1 (Octobre 2011) 

Public ISBD [article]  in Chemical engineering journal > Vol. 174 N° 1 (Octobre 2011) . - pp.175–181 Titre : A preliminary study of simultaneous lime treatment and dry digestion of smooth cordgrass for biogas production Type de document : texte imprimé Auteurs : Yuegan Liang, Auteur ; Zheng Zheng, Auteur ; Rimao Hua, Auteur Année de publication : 2012 Article en page(s) : pp.175–181 Note générale : Génie chimique Langues : Anglais (eng) Mots-clés : Smooth  cordgrass  Lime  treatment  Dry  digestion  Anaerobic  inhibition  First-order  kinetic Résumé : The technical feasibility of simultaneous lime treatment and dry digestion (SLTD) of smooth cordgrass in a leaching bed reactor at 55 ± 1 °C is discussed. SLTD was carried out in a single reactor with a high initial biogas production rate and volatile solids (VS) removal rate. Biogas yields reached 283.9 and 192.7 mL/g VS, with 10.0 and 9.5 L/d maximum biogas production rates for asynchronous lime treatment and dry digestion (ALTD), and SLTD, respectively. VS removal efficiency reached 69.0% and 71.9% for ALTD and SLTD, respectively. 83.7% and 99% total biogas yields were obtained at the beginning of 30 days digestion for ALTD and SLTD, respectively. The biogas production rate constant gradually reduced with the reduction of easily biodegradable material. Inhibition of anaerobic bacteria occurred at the SLTD experiment during dry digestion, as shown by very little total volatile fatty acid and biogas production after day 20. Sodium, potassium and calcium ions were not responsible for SLTD inhibition. ISSN : 1385-8947 En ligne : http://www.sciencedirect.com/science/article/pii/S1385894711010291 [article] A preliminary study of simultaneous lime treatment and dry digestion of smooth cordgrass for biogas production [texte imprimé] / Yuegan Liang, Auteur ; Zheng Zheng, Auteur ; Rimao Hua, Auteur . - 2012 . - pp.175–181. Génie chimique Langues : Anglais (eng) in Chemical engineering journal > Vol. 174 N° 1 (Octobre 2011) . - pp.175–181 Mots-clés : Smooth  cordgrass  Lime  treatment  Dry  digestion  Anaerobic  inhibition  First-order  kinetic Résumé : The technical feasibility of simultaneous lime treatment and dry digestion (SLTD) of smooth cordgrass in a leaching bed reactor at 55 ± 1 °C is discussed. SLTD was carried out in a single reactor with a high initial biogas production rate and volatile solids (VS) removal rate. Biogas yields reached 283.9 and 192.7 mL/g VS, with 10.0 and 9.5 L/d maximum biogas production rates for asynchronous lime treatment and dry digestion (ALTD), and SLTD, respectively. VS removal efficiency reached 69.0% and 71.9% for ALTD and SLTD, respectively. 83.7% and 99% total biogas yields were obtained at the beginning of 30 days digestion for ALTD and SLTD, respectively. The biogas production rate constant gradually reduced with the reduction of easily biodegradable material. Inhibition of anaerobic bacteria occurred at the SLTD experiment during dry digestion, as shown by very little total volatile fatty acid and biogas production after day 20. Sodium, potassium and calcium ions were not responsible for SLTD inhibition. ISSN : 1385-8947 En ligne : http://www.sciencedirect.com/science/article/pii/S1385894711010291

Comparative influential effects of mass transfer resistance in acetate - fed and glucose - fed sequential aerobic sludge blanket reactors / Hsin-Hsien Chou in Chemical engineering journal, Vol. 174 N° 1 (Octobre 2011) 

Public ISBD [article]  in Chemical engineering journal > Vol. 174 N° 1 (Octobre 2011) . - pp.182–189 Titre : Comparative influential effects of mass transfer resistance in acetate - fed and glucose - fed sequential aerobic sludge blanket reactors Type de document : texte imprimé Auteurs : Hsin-Hsien Chou, Auteur ; Ju-Sheng Huang, Auteur ; Chun-Wen Tsao, Auteur Année de publication : 2012 Article en page(s) : pp.182–189 Note générale : Génie chimique Langues : Anglais (eng) Mots-clés : Sequential  aerobic  sludge  blanket  Biodegradation  Mass  transfer  Kinetic  parameters  Modeling  Granule  characteristics Résumé : A laboratory study was undertaken to explore the influential effects of mass transfer resistance on overall substrate removal in acetate-fed and glucose-fed sequential aerobic sludge blanket reactors. In both reactors, solids retention time decreased with increasing OLR [2–8 kg chemical oxygen demand (COD)/m3 d], resulting in increasing specific substrate utilization rates. The obtained kinetic parameters values (k/Ks ratio) indicated that the microbial reaction rate for acetate was higher than that for glucose. The simulated mass transfer parameter values (ϕ2, Bi, L, and η) and substrate concentration profiles in the granule indicated that the overall substrate removal in the acetate-fed and glucose-fed reactors are intra-granular diffusion controlled, and the influential effect of intra-granular mass transfer resistance in the glucose-fed reactor is relatively greater. The simulated results also disclosed that the optimal dp for acetate-fed and glucose-fed reactors should be no greater than 3.5 and 2.5 mm, respectively. The validated kinetic model and the obtained kinetic parameter values can be appropriately used to simulate treatment performance of the SASB reactors treating simple substrates. ISSN : 1385-8947 En ligne : http://www.sciencedirect.com/science/article/pii/S1385894711010308 [article] Comparative influential effects of mass transfer resistance in acetate - fed and glucose - fed sequential aerobic sludge blanket reactors [texte imprimé] / Hsin-Hsien Chou, Auteur ; Ju-Sheng Huang, Auteur ; Chun-Wen Tsao, Auteur . - 2012 . - pp.182–189. Génie chimique Langues : Anglais (eng) in Chemical engineering journal > Vol. 174 N° 1 (Octobre 2011) . - pp.182–189 Mots-clés : Sequential  aerobic  sludge  blanket  Biodegradation  Mass  transfer  Kinetic  parameters  Modeling  Granule  characteristics Résumé : A laboratory study was undertaken to explore the influential effects of mass transfer resistance on overall substrate removal in acetate-fed and glucose-fed sequential aerobic sludge blanket reactors. In both reactors, solids retention time decreased with increasing OLR [2–8 kg chemical oxygen demand (COD)/m3 d], resulting in increasing specific substrate utilization rates. The obtained kinetic parameters values (k/Ks ratio) indicated that the microbial reaction rate for acetate was higher than that for glucose. The simulated mass transfer parameter values (ϕ2, Bi, L, and η) and substrate concentration profiles in the granule indicated that the overall substrate removal in the acetate-fed and glucose-fed reactors are intra-granular diffusion controlled, and the influential effect of intra-granular mass transfer resistance in the glucose-fed reactor is relatively greater. The simulated results also disclosed that the optimal dp for acetate-fed and glucose-fed reactors should be no greater than 3.5 and 2.5 mm, respectively. The validated kinetic model and the obtained kinetic parameter values can be appropriately used to simulate treatment performance of the SASB reactors treating simple substrates. ISSN : 1385-8947 En ligne : http://www.sciencedirect.com/science/article/pii/S1385894711010308

Alternate coating and porosity as dependent factors for the photocatalytic activity of sol – gel derived TiO2 films / Suhas R. Patil in Chemical engineering journal, Vol. 174 N° 1 (Octobre 2011) 

Public ISBD [article]  in Chemical engineering journal > Vol. 174 N° 1 (Octobre 2011) . - pp.190–198 Titre : Alternate coating and porosity as dependent factors for the photocatalytic activity of sol – gel derived TiO2 films Type de document : texte imprimé Auteurs : Suhas R. Patil, Auteur ; B.H. Hameed, Auteur ; Andrijna Sever Skapin, Auteur Année de publication : 2012 Article en page(s) : pp.190–198 Note générale : Génie chimique Langues : Anglais (eng) Mots-clés : Sol–gel  Mesoporous  TiO2  coatings  UV  light  Plasmocorinth  B  Photocatalytic  degradation Résumé : Surfactant-assisted anatase mesoporous TiO2 transparent films, along with P25 translucent films were successfully synthesized and deposited by dip-coating technique. Prepared films were characterized by UV–Vis spectroscopy, X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM), and N2 adsorption–desorption measurements. The hydrophilicity of films was assessed by water contact angle technique. The results revealed that the surfactant-assisted sol–gel films were homogeneous, crack-free, contained anatase phase only with small grain size, and showed an increase in BET surface area and wide range of pore size distribution compared to non-surfactant treated sample. The optical properties and photocatalytic activity of the films for an azo dye, Plasmocorinth B (PB) degradation were analyzed with UV–Vis spectrometer. The photocatalytic activity of the synthesized anatase TiO2 films having high optical quality is comparable to the activity of reference commercial powder P25 films. Relevant results are presented and discussed as a function of the structure and morphology of coatings, which control enables a direct tailoring of the functional response. The high porosity, uniformity, transparency, reliability, photocatalytic activity, good adhesion with the substrate and the excellent performance under cycling operation displayed by surfactant-assisted anatase TiO2 coatings make it a good candidate to be considered in new emerging engineering applications. ISSN : 1385-8947 En ligne : http://www.sciencedirect.com/science/article/pii/S1385894711010321 [article] Alternate coating and porosity as dependent factors for the photocatalytic activity of sol – gel derived TiO2 films [texte imprimé] / Suhas R. Patil, Auteur ; B.H. Hameed, Auteur ; Andrijna Sever Skapin, Auteur . - 2012 . - pp.190–198. Génie chimique Langues : Anglais (eng) in Chemical engineering journal > Vol. 174 N° 1 (Octobre 2011) . - pp.190–198 Mots-clés : Sol–gel  Mesoporous  TiO2  coatings  UV  light  Plasmocorinth  B  Photocatalytic  degradation Résumé : Surfactant-assisted anatase mesoporous TiO2 transparent films, along with P25 translucent films were successfully synthesized and deposited by dip-coating technique. Prepared films were characterized by UV–Vis spectroscopy, X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM), and N2 adsorption–desorption measurements. The hydrophilicity of films was assessed by water contact angle technique. The results revealed that the surfactant-assisted sol–gel films were homogeneous, crack-free, contained anatase phase only with small grain size, and showed an increase in BET surface area and wide range of pore size distribution compared to non-surfactant treated sample. The optical properties and photocatalytic activity of the films for an azo dye, Plasmocorinth B (PB) degradation were analyzed with UV–Vis spectrometer. The photocatalytic activity of the synthesized anatase TiO2 films having high optical quality is comparable to the activity of reference commercial powder P25 films. Relevant results are presented and discussed as a function of the structure and morphology of coatings, which control enables a direct tailoring of the functional response. The high porosity, uniformity, transparency, reliability, photocatalytic activity, good adhesion with the substrate and the excellent performance under cycling operation displayed by surfactant-assisted anatase TiO2 coatings make it a good candidate to be considered in new emerging engineering applications. ISSN : 1385-8947 En ligne : http://www.sciencedirect.com/science/article/pii/S1385894711010321

Self - assembled nanoparticles from thermo - sensitive polyion complex micelles for controlled drug release / Guiying Li in Chemical engineering journal, Vol. 174 N° 1 (Octobre 2011) 

Public ISBD [article]  in Chemical engineering journal > Vol. 174 N° 1 (Octobre 2011) . - pp. 199–205 Titre : Self - assembled nanoparticles from thermo - sensitive polyion complex micelles for controlled drug release Type de document : texte imprimé Auteurs : Guiying Li, Auteur ; Lei Guo, Auteur ; Yanfeng Meng, Auteur Année de publication : 2012 Article en page(s) : pp. 199–205 Note générale : Génie chimique Langues : Anglais (eng) Mots-clés : Controlled  release  Polyion  complex  micelles  Nanoparticles  CS  -g  -  PNIPAM  P(tBA  -  co  -  AA)-  b  -  PNIPAM Résumé : Self-assembled nanoparticles from thermo-sensitive polyion complex (PIC) micelles comprised of poly(t-butyl acrylate-co-acrylic acid)-b-poly(N-isopropylacrylamide) [P(tBA-co-AA)-b-PNIPAM] core–shell micelles and graft copolymer chitosan-g-poly(N-isopropylacrylamide) (CS-g-PNIPAM) were developed for applications in controlled drug release. The PIC micelles nanoparticles had a multi-layer core–shell–corona structure with hydrophobic PtBA as the inner core, negatively charged PAA and positively charged CS forming the middle layer as the shell, and thermo-sensitive PNIPAM as the outer corona. The molar ratio of P(tBA-co-AA)-b-PNIPAM to CS-g-PNIPAM affected the functionalities and hydrodynamic diameters of nanoparticles. Release of doxorubicin (DOX) from micelles was suppressed at neutral solutions due to the stability of electrostatic interactions but accelerated at acidic solutions or high temperatures above LCST. This study presents new micelles with a functional inner shell whose structure can be rapidly damaged to release charged drugs when the microenvironment of micelles changed. ISSN : 1385-8947 En ligne : http://www.sciencedirect.com/science/article/pii/S1385894711010540 [article] Self - assembled nanoparticles from thermo - sensitive polyion complex micelles for controlled drug release [texte imprimé] / Guiying Li, Auteur ; Lei Guo, Auteur ; Yanfeng Meng, Auteur . - 2012 . - pp. 199–205. Génie chimique Langues : Anglais (eng) in Chemical engineering journal > Vol. 174 N° 1 (Octobre 2011) . - pp. 199–205 Mots-clés : Controlled  release  Polyion  complex  micelles  Nanoparticles  CS  -g  -  PNIPAM  P(tBA  -  co  -  AA)-  b  -  PNIPAM Résumé : Self-assembled nanoparticles from thermo-sensitive polyion complex (PIC) micelles comprised of poly(t-butyl acrylate-co-acrylic acid)-b-poly(N-isopropylacrylamide) [P(tBA-co-AA)-b-PNIPAM] core–shell micelles and graft copolymer chitosan-g-poly(N-isopropylacrylamide) (CS-g-PNIPAM) were developed for applications in controlled drug release. The PIC micelles nanoparticles had a multi-layer core–shell–corona structure with hydrophobic PtBA as the inner core, negatively charged PAA and positively charged CS forming the middle layer as the shell, and thermo-sensitive PNIPAM as the outer corona. The molar ratio of P(tBA-co-AA)-b-PNIPAM to CS-g-PNIPAM affected the functionalities and hydrodynamic diameters of nanoparticles. Release of doxorubicin (DOX) from micelles was suppressed at neutral solutions due to the stability of electrostatic interactions but accelerated at acidic solutions or high temperatures above LCST. This study presents new micelles with a functional inner shell whose structure can be rapidly damaged to release charged drugs when the microenvironment of micelles changed. ISSN : 1385-8947 En ligne : http://www.sciencedirect.com/science/article/pii/S1385894711010540

Transformation of beneficially reused aluminium sludge to potential P and Al resource after employing as P - trapping material for wastewater treatment in constructed wetland / X.H. Zhao in Chemical engineering journal, Vol. 174 N° 1 (Octobre 2011) 

Public ISBD [article]  in Chemical engineering journal > Vol. 174 N° 1 (Octobre 2011) . - pp. 206–212 Titre : Transformation of beneficially reused aluminium sludge to potential P and Al resource after employing as P - trapping material for wastewater treatment in constructed wetland Type de document : texte imprimé Auteurs : X.H. Zhao, Auteur ; Y.Q. Zhao, Auteur ; P. Kearney, Auteur Année de publication : 2012 Article en page(s) : pp. 206–212 Note générale : Génie chimique Langues : Anglais (eng) Mots-clés : P  resource  Aluminium  sludge  P  recovery  Chemical  precipitation Résumé : The phosphorus (P)-saturated aluminium sludge used as substrate in constructed wetland (CW) for P-rich wastewater treatment was investigated to recover P and Al through chemical precipitations of the P-extraction leachate of the used aluminium sludge. pH plays a key role in such the precipitation processes. The obtained compounds were identified with XRD, FTIR and SEM analyses. The results showed that over 99% PO43− could be recovered as hydroxyapatite by adding calcium chloride at pH of 13. The remaining Al could be fully recovered as amorphous aluminium hydroxide at pH of 7.0 or alternatively as tris(8-hydroxyquinolino)aluminium (Alq3) by adding suitable quantity of 8-hydroxyquinoline. Although the purity, structure, characteristics and production control of the compounds are worthy for further investigation, this study successfully developed a post-treatment methodology for beneficially reused aluminium sludge. The significance of this study is not only transferring aluminium sludge from “waste” to potential P and Al resources but also reducing the environmental risk of final disposal of used aluminium sludge. ISSN : 1385-8947 En ligne : http://www.sciencedirect.com/science/article/pii/S138589471101059X [article] Transformation of beneficially reused aluminium sludge to potential P and Al resource after employing as P - trapping material for wastewater treatment in constructed wetland [texte imprimé] / X.H. Zhao, Auteur ; Y.Q. Zhao, Auteur ; P. Kearney, Auteur . - 2012 . - pp. 206–212. Génie chimique Langues : Anglais (eng) in Chemical engineering journal > Vol. 174 N° 1 (Octobre 2011) . - pp. 206–212 Mots-clés : P  resource  Aluminium  sludge  P  recovery  Chemical  precipitation Résumé : The phosphorus (P)-saturated aluminium sludge used as substrate in constructed wetland (CW) for P-rich wastewater treatment was investigated to recover P and Al through chemical precipitations of the P-extraction leachate of the used aluminium sludge. pH plays a key role in such the precipitation processes. The obtained compounds were identified with XRD, FTIR and SEM analyses. The results showed that over 99% PO43− could be recovered as hydroxyapatite by adding calcium chloride at pH of 13. The remaining Al could be fully recovered as amorphous aluminium hydroxide at pH of 7.0 or alternatively as tris(8-hydroxyquinolino)aluminium (Alq3) by adding suitable quantity of 8-hydroxyquinoline. Although the purity, structure, characteristics and production control of the compounds are worthy for further investigation, this study successfully developed a post-treatment methodology for beneficially reused aluminium sludge. The significance of this study is not only transferring aluminium sludge from “waste” to potential P and Al resources but also reducing the environmental risk of final disposal of used aluminium sludge. ISSN : 1385-8947 En ligne : http://www.sciencedirect.com/science/article/pii/S138589471101059X

Development and utilization of aerobic granules for the palm oil mill (POM) wastewater treatment / K. Gobi in Chemical engineering journal, Vol. 174 N° 1 (Octobre 2011) 

Public ISBD [article]  in Chemical engineering journal > Vol. 174 N° 1 (Octobre 2011) . - pp. 213–220 Titre : Development and utilization of aerobic granules for the palm oil mill (POM) wastewater treatment Type de document : texte imprimé Auteurs : K. Gobi, Auteur ; M.D. Mashitah, Auteur ; V.M. Vadivelu, Auteur Année de publication : 2012 Article en page(s) : pp. 213–220 Note générale : Génie chimique Langues : Anglais (eng) Mots-clés : Aerobic  granules  Aerobic  granules  POM  wastewater  Response  Surface  Methodology  (RSM) Résumé : The high COD and turbidity level of palm oil mill (POM) wastewater has been the driving force to find an efficient treatment system. In this work, biological and adsorption methods are integrated and used to treat the POM wastewater. In biological treatment, aerobic granules are developed and used in the sequencing batch reactor (SBR), whereas in adsorption treatment, the waste aerobic granules (WAG) are utilized as adsorbent. Response Surface Methodology (RSM) has been used to model and optimize the adsorption of biologically treated POM wastewater. Aerobic granules took 110 days to appear and the average diameter was 0.9 mm (with a maximum value of 3.1 mm). The aerobic granules are able to remove 88% of the influent COD at organic loading rate (OLR) of 3.0 kg COD/m3 day. The increase of OLR to 6.0 kg COD/m3 day did not affect the COD removal efficiency and the aerobic granules immediately responded to the OLR increase. The adsorption system revealed that the 21% of the remaining COD (of the biologically treated POM wastewater) and almost 99% of the turbidity were removed. At optimum point (3.28 cm of bed height and 2.13 ml/min flow rate), the amount of COD and turbidity removed are 21% and 96%, respectively. ISSN : 1385-8947 En ligne : http://www.sciencedirect.com/science/article/pii/S1385894711010606 [article] Development and utilization of aerobic granules for the palm oil mill (POM) wastewater treatment [texte imprimé] / K. Gobi, Auteur ; M.D. Mashitah, Auteur ; V.M. Vadivelu, Auteur . - 2012 . - pp. 213–220. Génie chimique Langues : Anglais (eng) in Chemical engineering journal > Vol. 174 N° 1 (Octobre 2011) . - pp. 213–220 Mots-clés : Aerobic  granules  Aerobic  granules  POM  wastewater  Response  Surface  Methodology  (RSM) Résumé : The high COD and turbidity level of palm oil mill (POM) wastewater has been the driving force to find an efficient treatment system. In this work, biological and adsorption methods are integrated and used to treat the POM wastewater. In biological treatment, aerobic granules are developed and used in the sequencing batch reactor (SBR), whereas in adsorption treatment, the waste aerobic granules (WAG) are utilized as adsorbent. Response Surface Methodology (RSM) has been used to model and optimize the adsorption of biologically treated POM wastewater. Aerobic granules took 110 days to appear and the average diameter was 0.9 mm (with a maximum value of 3.1 mm). The aerobic granules are able to remove 88% of the influent COD at organic loading rate (OLR) of 3.0 kg COD/m3 day. The increase of OLR to 6.0 kg COD/m3 day did not affect the COD removal efficiency and the aerobic granules immediately responded to the OLR increase. The adsorption system revealed that the 21% of the remaining COD (of the biologically treated POM wastewater) and almost 99% of the turbidity were removed. At optimum point (3.28 cm of bed height and 2.13 ml/min flow rate), the amount of COD and turbidity removed are 21% and 96%, respectively. ISSN : 1385-8947 En ligne : http://www.sciencedirect.com/science/article/pii/S1385894711010606

Performance of rattle - type magnetic mesoporous silica spheres in the adsorption of single and binary antibiotics / Longcheng Xu in Chemical engineering journal, Vol. 174 N° 1 (Octobre 2011) 

Public ISBD [article]  in Chemical engineering journal > Vol. 174 N° 1 (Octobre 2011) . - pp.221–230 Titre : Performance of rattle - type magnetic mesoporous silica spheres in the adsorption of single and binary antibiotics Type de document : texte imprimé Auteurs : Longcheng Xu, Auteur ; Jiangdong Dai, Auteur ; Jiangming Pan, Auteur Année de publication : 2012 Article en page(s) : pp.221–230 Note générale : Génie chimique Langues : Anglais (eng) Mots-clés : y-Fe2O3/mSiO2  spheres  Tetracycline  Sulfamethazine  Adsorption Résumé : The rattle-type γ-Fe2O3/mesoporous silica spheres (γ-Fe2O3/mSiO2 spheres) were synthesized with a facial and selectively etching strategy. The prepared particles were characterized by FT-IR, XRD, TEM, SEM, VSM, Raman spectroscopy and nitrogen adsorption–desorption analysis, and the results indicated that γ-Fe2O3/mSiO2 spheres exhibited magnetic property (Ms = 14.43 emu g−1) and composed of mesoporous silica (mean diameter, thickness and pore size was 660 nm, 60 nm, and 2.29 nm, respectively). Then the γ-Fe2O3/mSiO2 spheres were employed as sorbents to remove tetracycline (TC) and sulfamethazine (SMZ) in both single and binary aqueous solutions. The adsorption kinetics of γ-Fe2O3/mSiO2 spheres were well-described by the pseudo-second-order equation, initial adsorption rate, and half-adsorption time. The Langmuir isotherm model was fitted to the equilibrium data better than that for Freundlich model, and the monolayer adsorption capacity of γ-Fe2O3/mSiO2 spheres for TC and SMZ were 0.0791 mmol g−1 and 0.0342 mmol g−1 at 298 K, respectively. In binary systems, SMZ adsorption onto γ-Fe2O3/mSiO2 spheres was more affected by the simultaneous presence of competitive antibiotics than that for TC. In addition, the reusability of the material without obviously deterioration in performance was observed at least four repealed cycles. ISSN : 1385-8947 En ligne : http://www.sciencedirect.com/science/article/pii/S1385894711010618 [article] Performance of rattle - type magnetic mesoporous silica spheres in the adsorption of single and binary antibiotics [texte imprimé] / Longcheng Xu, Auteur ; Jiangdong Dai, Auteur ; Jiangming Pan, Auteur . - 2012 . - pp.221–230. Génie chimique Langues : Anglais (eng) in Chemical engineering journal > Vol. 174 N° 1 (Octobre 2011) . - pp.221–230 Mots-clés : y-Fe2O3/mSiO2  spheres  Tetracycline  Sulfamethazine  Adsorption Résumé : The rattle-type γ-Fe2O3/mesoporous silica spheres (γ-Fe2O3/mSiO2 spheres) were synthesized with a facial and selectively etching strategy. The prepared particles were characterized by FT-IR, XRD, TEM, SEM, VSM, Raman spectroscopy and nitrogen adsorption–desorption analysis, and the results indicated that γ-Fe2O3/mSiO2 spheres exhibited magnetic property (Ms = 14.43 emu g−1) and composed of mesoporous silica (mean diameter, thickness and pore size was 660 nm, 60 nm, and 2.29 nm, respectively). Then the γ-Fe2O3/mSiO2 spheres were employed as sorbents to remove tetracycline (TC) and sulfamethazine (SMZ) in both single and binary aqueous solutions. The adsorption kinetics of γ-Fe2O3/mSiO2 spheres were well-described by the pseudo-second-order equation, initial adsorption rate, and half-adsorption time. The Langmuir isotherm model was fitted to the equilibrium data better than that for Freundlich model, and the monolayer adsorption capacity of γ-Fe2O3/mSiO2 spheres for TC and SMZ were 0.0791 mmol g−1 and 0.0342 mmol g−1 at 298 K, respectively. In binary systems, SMZ adsorption onto γ-Fe2O3/mSiO2 spheres was more affected by the simultaneous presence of competitive antibiotics than that for TC. In addition, the reusability of the material without obviously deterioration in performance was observed at least four repealed cycles. ISSN : 1385-8947 En ligne : http://www.sciencedirect.com/science/article/pii/S1385894711010618

Citrate route to prepare K-doped Li2ZrO3 sorbents with excellent CO2 capture properties / Qiang Xiao in Chemical engineering journal, Vol. 174 N° 1 (Octobre 2011) 

Public ISBD [article]  in Chemical engineering journal > Vol. 174 N° 1 (Octobre 2011) . - pp. 231–235 Titre : Citrate route to prepare K-doped Li2ZrO3 sorbents with excellent CO2 capture properties Type de document : texte imprimé Auteurs : Qiang Xiao, Auteur ; Xiaodan Tang, Auteur ; Yefeng Liu, Auteur Année de publication : 2012 Article en page(s) : pp. 231–235 Note générale : Génie chimique Langues : Anglais (eng) Mots-clés : Nanoparticles  Citrate  CO2  capture  K-doped  Li2ZrO3  Hydrogen  production Résumé : K-doped Li2ZrO3 sorbents with excellent CO2 capture properties were synthesized via a citrate route. The CO2 capture–regeneration properties of these synthesized K-doped Li2ZrO3 sorbents were investigated by thermogravimetric analysis (TGA) at different temperatures and CO2 partial pressures. The synthesized K-doped Li2ZrO3 sorbents possess a better CO2 capture performance than reported Li2ZrO3-based ones, especially at low CO2 partial pressures. At 823 K and a CO2 partial pressure of 0.25 bar, the uptake of CO2 in the K-doped Li2ZrO3 with an optimized K:Li:Zr composition of 0.2:1.6:1 in molar ratio can reach 23 wt.% within 15 min. Furthermore, the sorbent displays a good stability, confirmed by CO2 capture–regeneration cycles. ISSN : 1385-8947 En ligne : http://www.sciencedirect.com/science/article/pii/S1385894711010631 [article] Citrate route to prepare K-doped Li2ZrO3 sorbents with excellent CO2 capture properties [texte imprimé] / Qiang Xiao, Auteur ; Xiaodan Tang, Auteur ; Yefeng Liu, Auteur . - 2012 . - pp. 231–235. Génie chimique Langues : Anglais (eng) in Chemical engineering journal > Vol. 174 N° 1 (Octobre 2011) . - pp. 231–235 Mots-clés : Nanoparticles  Citrate  CO2  capture  K-doped  Li2ZrO3  Hydrogen  production Résumé : K-doped Li2ZrO3 sorbents with excellent CO2 capture properties were synthesized via a citrate route. The CO2 capture–regeneration properties of these synthesized K-doped Li2ZrO3 sorbents were investigated by thermogravimetric analysis (TGA) at different temperatures and CO2 partial pressures. The synthesized K-doped Li2ZrO3 sorbents possess a better CO2 capture performance than reported Li2ZrO3-based ones, especially at low CO2 partial pressures. At 823 K and a CO2 partial pressure of 0.25 bar, the uptake of CO2 in the K-doped Li2ZrO3 with an optimized K:Li:Zr composition of 0.2:1.6:1 in molar ratio can reach 23 wt.% within 15 min. Furthermore, the sorbent displays a good stability, confirmed by CO2 capture–regeneration cycles. ISSN : 1385-8947 En ligne : http://www.sciencedirect.com/science/article/pii/S1385894711010631

Synthesis of acetyl salicylic acid over WO3/ZrO2 solid superacid catalyst / Cun Zhang in Chemical engineering journal, Vol. 174 N° 1 (Octobre 2011) 

Public ISBD [article]  in Chemical engineering journal > Vol. 174 N° 1 (Octobre 2011) . - pp. 236–241 Titre : Synthesis of acetyl salicylic acid over WO3/ZrO2 solid superacid catalyst Type de document : texte imprimé Auteurs : Cun Zhang, Auteur ; Tao Liu, Auteur ; Hong-Juan Wang, Auteur Année de publication : 2012 Article en page(s) : pp. 236–241 Note générale : Génie chimique Langues : Anglais (eng) Mots-clés : Acetyl  salicylic  acid  Solid  superacid  WO3/ZrO2  catalyst Résumé : Solid superacid WO3/ZrO2 was prepared by co-precipitation of an aqueous zirconyl chloride and ammonium metatungstate solution. The as-prepared catalysts were characterized by using XRD, Laser Raman spectroscopy and BET. Acetyl salicylic acid was synthesized from salicylic acid and acetic anhydride using as-synthesized WO3/ZrO2. The effects of WO3 concentration, reaction time, reaction temperature, molar ratio of reactants, as well as dosage of catalysts on synthesis of acetyl salicylic acid were investigated, and the reaction conditions were therefore optimized. The excellent yield (91.0%) of acetylsalicylic acid was obtained under optimized reaction conditions. The catalyst has been easily recovered and reused repeatedly with a consistent high yield. ISSN : 1385-8947 En ligne : http://www.sciencedirect.com/science/article/pii/S1385894711010680 [article] Synthesis of acetyl salicylic acid over WO3/ZrO2 solid superacid catalyst [texte imprimé] / Cun Zhang, Auteur ; Tao Liu, Auteur ; Hong-Juan Wang, Auteur . - 2012 . - pp. 236–241. Génie chimique Langues : Anglais (eng) in Chemical engineering journal > Vol. 174 N° 1 (Octobre 2011) . - pp. 236–241 Mots-clés : Acetyl  salicylic  acid  Solid  superacid  WO3/ZrO2  catalyst Résumé : Solid superacid WO3/ZrO2 was prepared by co-precipitation of an aqueous zirconyl chloride and ammonium metatungstate solution. The as-prepared catalysts were characterized by using XRD, Laser Raman spectroscopy and BET. Acetyl salicylic acid was synthesized from salicylic acid and acetic anhydride using as-synthesized WO3/ZrO2. The effects of WO3 concentration, reaction time, reaction temperature, molar ratio of reactants, as well as dosage of catalysts on synthesis of acetyl salicylic acid were investigated, and the reaction conditions were therefore optimized. The excellent yield (91.0%) of acetylsalicylic acid was obtained under optimized reaction conditions. The catalyst has been easily recovered and reused repeatedly with a consistent high yield. ISSN : 1385-8947 En ligne : http://www.sciencedirect.com/science/article/pii/S1385894711010680

Regeneration of field - spent activated carbon catalysts for low - temperature selective catalytic reduction of NOx with NH3 / Jong-Ki Jeon in Chemical engineering journal, Vol. 174 N° 1 (Octobre 2011) 

Public ISBD [article]  in Chemical engineering journal > Vol. 174 N° 1 (Octobre 2011) . - pp. 242–248 Titre : Regeneration of field - spent activated carbon catalysts for low - temperature selective catalytic reduction of NOx with NH3 Type de document : texte imprimé Auteurs : Jong-Ki Jeon, Auteur ; Hyeonjoo Kim, Auteur ; Young-Kwon Park, Auteur Année de publication : 2012 Article en page(s) : pp. 242–248 Note générale : Génie chimique Langues : Anglais (eng) Mots-clés : Selective  catalytic  reduction  with  NH3  DeNOx  Activated  carbon  Boron  Deactivation  Catalyst  regeneration Résumé : In the process of producing liquid crystal displays (LCD), the emitted NOx is removed over an activated carbon catalyst by using selective catalytic reduction (SCR) with NH3 at low temperature. However, the catalyst rapidly deactivates primarily due to the deposition of boron discharged from the process onto the catalyst. Therefore, this study is aimed at developing an optimal regeneration process to remove boron from field-spent carbon catalysts. The spent carbon catalysts were regenerated by washing with a surfactant followed by drying and calcination. The physicochemical properties before and after the regeneration were investigated by using elemental analysis, TG/DTG (thermogravimetric/differential thermogravimetric) analysis, N2 adsorption–desorption and NH3 TPD (temperature programmed desorption). Spent carbon catalysts demonstrated a drastic decrease in DeNOx activity mainly due to heavy deposition of boron. Boron was accumulated to depths of about 50 μm inside the granule surface of the activated carbons, as evidenced by cross-sectional SEM-EDX analysis. However, catalyst activity and surface area were significantly recovered by removing boron in the regeneration process, and the highest NO conversions were obtained after washing with a non-ionic surfactant in H2O at 70 °C, followed by treatment with N2 at 550 °C. ISSN : 1385-8947 En ligne : http://www.sciencedirect.com/science/article/pii/S1385894711010692 [article] Regeneration of field - spent activated carbon catalysts for low - temperature selective catalytic reduction of NOx with NH3 [texte imprimé] / Jong-Ki Jeon, Auteur ; Hyeonjoo Kim, Auteur ; Young-Kwon Park, Auteur . - 2012 . - pp. 242–248. Génie chimique Langues : Anglais (eng) in Chemical engineering journal > Vol. 174 N° 1 (Octobre 2011) . - pp. 242–248 Mots-clés : Selective  catalytic  reduction  with  NH3  DeNOx  Activated  carbon  Boron  Deactivation  Catalyst  regeneration Résumé : In the process of producing liquid crystal displays (LCD), the emitted NOx is removed over an activated carbon catalyst by using selective catalytic reduction (SCR) with NH3 at low temperature. However, the catalyst rapidly deactivates primarily due to the deposition of boron discharged from the process onto the catalyst. Therefore, this study is aimed at developing an optimal regeneration process to remove boron from field-spent carbon catalysts. The spent carbon catalysts were regenerated by washing with a surfactant followed by drying and calcination. The physicochemical properties before and after the regeneration were investigated by using elemental analysis, TG/DTG (thermogravimetric/differential thermogravimetric) analysis, N2 adsorption–desorption and NH3 TPD (temperature programmed desorption). Spent carbon catalysts demonstrated a drastic decrease in DeNOx activity mainly due to heavy deposition of boron. Boron was accumulated to depths of about 50 μm inside the granule surface of the activated carbons, as evidenced by cross-sectional SEM-EDX analysis. However, catalyst activity and surface area were significantly recovered by removing boron in the regeneration process, and the highest NO conversions were obtained after washing with a non-ionic surfactant in H2O at 70 °C, followed by treatment with N2 at 550 °C. ISSN : 1385-8947 En ligne : http://www.sciencedirect.com/science/article/pii/S1385894711010692

A parametric study of electrocoagulation as a recovery process of marine microalgae for biodiesel production / Nyomi Uduman in Chemical engineering journal, Vol. 174 N° 1 (Octobre 2011) 

Public ISBD [article]  in Chemical engineering journal > Vol. 174 N° 1 (Octobre 2011) . - pp.249–257 Titre : A parametric study of electrocoagulation as a recovery process of marine microalgae for biodiesel production Type de document : texte imprimé Auteurs : Nyomi Uduman, Auteur ; Vivien Bourniquel, Auteur ; Michael K. Danquah, Auteur Année de publication : 2012 Article en page(s) : pp.249–257 Note générale : Génie chimique Langues : Anglais (eng) Mots-clés : Electrocoagulation  Dewatering  Microalgae  separation  Biodiesel  Zeta  potential Résumé : Microalgal biomass as feedstock for biofuel production is rapidly gaining appreciation in response to the increasing petroleum prices and the upsurge in global warming concerns. However, the process of creating concentrated biomass from microalgal cultures is limited by ineffective dewatering procedures. The economics of existing culture clarification unit operations make the process of creating biomass from microalgae unattractive for biofuel development. This work involves the comparison of the removal efficiency (recovery) of two marine microalgae species Chlorococcum sp. and Tetraselmis sp. by electrocoagulation (EC), a technique that has not been thoroughly explored in marine microalgae dewatering. High recovery efficiencies were obtained of up to 99 and 98% for Tetraselmis sp. and Chlorococcum sp., respectively. The effect of culture temperature and salinity on removal efficiency was also observed. A starting temperature of 60 °C resulted in optimal recovery values of 96 and 94% for Chlorococcum sp. and Tetraselmis sp., respectively. Whereas a starting temperature of 5 °C achieved optimal recovery of only 5 and 68% for Chlorococcum sp. and Tetraselmis sp., respectively. Increased salinity of microalgae culture showed increased microalgae recovery. Salinity of 20% gave optimal microalgae recovery values of only 6 and 9% for Chlorococcum sp. and Tetraselmis sp., respectively. Zeta potential (ZP) analysis was carried out to verify and further understand the charge neutralization mechanism due to Fe2+ cations. ISSN : 1385-8947 En ligne : http://www.sciencedirect.com/science/article/pii/S1385894711010709 [article] A parametric study of electrocoagulation as a recovery process of marine microalgae for biodiesel production [texte imprimé] / Nyomi Uduman, Auteur ; Vivien Bourniquel, Auteur ; Michael K. Danquah, Auteur . - 2012 . - pp.249–257. Génie chimique Langues : Anglais (eng) in Chemical engineering journal > Vol. 174 N° 1 (Octobre 2011) . - pp.249–257 Mots-clés : Electrocoagulation  Dewatering  Microalgae  separation  Biodiesel  Zeta  potential Résumé : Microalgal biomass as feedstock for biofuel production is rapidly gaining appreciation in response to the increasing petroleum prices and the upsurge in global warming concerns. However, the process of creating concentrated biomass from microalgal cultures is limited by ineffective dewatering procedures. The economics of existing culture clarification unit operations make the process of creating biomass from microalgae unattractive for biofuel development. This work involves the comparison of the removal efficiency (recovery) of two marine microalgae species Chlorococcum sp. and Tetraselmis sp. by electrocoagulation (EC), a technique that has not been thoroughly explored in marine microalgae dewatering. High recovery efficiencies were obtained of up to 99 and 98% for Tetraselmis sp. and Chlorococcum sp., respectively. The effect of culture temperature and salinity on removal efficiency was also observed. A starting temperature of 60 °C resulted in optimal recovery values of 96 and 94% for Chlorococcum sp. and Tetraselmis sp., respectively. Whereas a starting temperature of 5 °C achieved optimal recovery of only 5 and 68% for Chlorococcum sp. and Tetraselmis sp., respectively. Increased salinity of microalgae culture showed increased microalgae recovery. Salinity of 20% gave optimal microalgae recovery values of only 6 and 9% for Chlorococcum sp. and Tetraselmis sp., respectively. Zeta potential (ZP) analysis was carried out to verify and further understand the charge neutralization mechanism due to Fe2+ cations. ISSN : 1385-8947 En ligne : http://www.sciencedirect.com/science/article/pii/S1385894711010709

Inhibiting 1,3 - dinitrobenzene formation in fenton oxidation of nitrobenzene through a controllable reductive pretreatment with zero - valent iron / Bi-Cun Jiang in Chemical engineering journal, Vol. 174 N° 1 (Octobre 2011) 

Public ISBD [article]  in Chemical engineering journal > Vol. 174 N° 1 (Octobre 2011) . - pp.258–265 Titre : Inhibiting 1,3 - dinitrobenzene formation in fenton oxidation of nitrobenzene through a controllable reductive pretreatment with zero - valent iron Type de document : texte imprimé Auteurs : Bi-Cun Jiang, Auteur ; Zhao-Yang Lu, Auteur ; Fu-Qiang Liu, Auteur Année de publication : 2012 Article en page(s) : pp.258–265 Note générale : Génie chimique Langues : Anglais (eng) Mots-clés : Fenton  Nitrobenzene  Zero-valent  iron  1,3-Dinitrobenzene Résumé : Nitrobenzene (NB) oxidation through conventional Fenton process produces a considerable amount of highly toxic 1,3-dinitrobenzene (1,3-DNB) as a byproduct. Aiming at significantly decreasing 1,3-DNB production in Fenton process, we developed a novel system integrating a reductive pretreatment via zero-valent iron (ZVI) with Fenton process to degrade NB in aqueous solution and industrial wastewater. The NB reduction efficiency of ZVI pretreatment could be controlled by adjusting the initial ZVI concentration and/or the initial pH of NB solution in a completely stirred ZVI reactor. After partial NB reduction by ZVI pretreatment, the residual NB was oxidized by a subsequent Fenton process. Aniline and ferrous irons were generated in ZVI pretreatment, producing an inhibitory effect on the formation of 1,3-DNB in Fenton process. While conventional Fenton process attained the NB removal efficiency of 95.0% and brought the relative 1,3-DNB yield (the molar concentration of 1,3-DNB in relation to that of converted NB) of 5.0%, the integrated system with the NB reduction efficiency of 48.1% achieved a similarly high NB removal efficiency (93.0%), but its relative 1,3-DNB yield was only 0.4%. Applied to the full-scale treatment of NB-rich industrial wastewater, the ZVI-Fenton integrated system with the NB reduction efficiency of 50.0% and conventional Fenton process produced dinitrobenzene isomers at the total concentrations of 0.005 mM and 0.060 mM, respectively. Accordingly, the integrated system increased the biodegradability and decreased the acute toxicity of the wastewater significantly more than conventional Fenton process. Therefore, the novel ZVI-Fenton integrated process is effective in the degradation of NB wastewater. ISSN : 1385-8947 En ligne : http://www.sciencedirect.com/science/article/pii/S1385894711010722 [article] Inhibiting 1,3 - dinitrobenzene formation in fenton oxidation of nitrobenzene through a controllable reductive pretreatment with zero - valent iron [texte imprimé] / Bi-Cun Jiang, Auteur ; Zhao-Yang Lu, Auteur ; Fu-Qiang Liu, Auteur . - 2012 . - pp.258–265. Génie chimique Langues : Anglais (eng) in Chemical engineering journal > Vol. 174 N° 1 (Octobre 2011) . - pp.258–265 Mots-clés : Fenton  Nitrobenzene  Zero-valent  iron  1,3-Dinitrobenzene Résumé : Nitrobenzene (NB) oxidation through conventional Fenton process produces a considerable amount of highly toxic 1,3-dinitrobenzene (1,3-DNB) as a byproduct. Aiming at significantly decreasing 1,3-DNB production in Fenton process, we developed a novel system integrating a reductive pretreatment via zero-valent iron (ZVI) with Fenton process to degrade NB in aqueous solution and industrial wastewater. The NB reduction efficiency of ZVI pretreatment could be controlled by adjusting the initial ZVI concentration and/or the initial pH of NB solution in a completely stirred ZVI reactor. After partial NB reduction by ZVI pretreatment, the residual NB was oxidized by a subsequent Fenton process. Aniline and ferrous irons were generated in ZVI pretreatment, producing an inhibitory effect on the formation of 1,3-DNB in Fenton process. While conventional Fenton process attained the NB removal efficiency of 95.0% and brought the relative 1,3-DNB yield (the molar concentration of 1,3-DNB in relation to that of converted NB) of 5.0%, the integrated system with the NB reduction efficiency of 48.1% achieved a similarly high NB removal efficiency (93.0%), but its relative 1,3-DNB yield was only 0.4%. Applied to the full-scale treatment of NB-rich industrial wastewater, the ZVI-Fenton integrated system with the NB reduction efficiency of 50.0% and conventional Fenton process produced dinitrobenzene isomers at the total concentrations of 0.005 mM and 0.060 mM, respectively. Accordingly, the integrated system increased the biodegradability and decreased the acute toxicity of the wastewater significantly more than conventional Fenton process. Therefore, the novel ZVI-Fenton integrated process is effective in the degradation of NB wastewater. ISSN : 1385-8947 En ligne : http://www.sciencedirect.com/science/article/pii/S1385894711010722

Oxidation of carboxylic acids in water at IrO2 – Ta2O5 and boron doped diamond anodes / Onofrio Scialdone in Chemical engineering journal, Vol. 174 N° 1 (Octobre 2011) 

Public ISBD [article]  in Chemical engineering journal > Vol. 174 N° 1 (Octobre 2011) . - pp. 266–274 Titre : Oxidation of carboxylic acids in water at IrO2 – Ta2O5 and boron doped diamond anodes Type de document : texte imprimé Auteurs : Onofrio Scialdone, Auteur ; Alessandro Galia, Auteur ; Serena Randazzo, Auteur Année de publication : 2012 Article en page(s) : pp. 266–274 Note générale : Génie chimique Langues : Anglais (eng) Mots-clés : Electrochemical  incineration  Carboxylic  acids  BDD  DSA  Iridium  anode  AOPs  Oxidation  of  organics Résumé : A detailed study was dedicated to the anodic oxidation of three carboxylic acids (namely, oxalic, formic and maleic acid) with the objective to evaluate in a systematic way the effect on the oxidation of carboxylic acids of numerous relevant parameters, including the nature and the concentration of the carboxylic acid, the alimentation regime (potentiostatic vs. amperostatic), the current density and the working potential values, the flowdynamic regime, the temperature and the nature of the electrode material. It was observed that the effect of some operative parameters strongly depends on the nature of the electrode and of the carboxylic acid. As an example, the efficacy of abatement decreased in the order oxalic > formic ≫ maleic at iridium anodes while an opposite trend was observed at diamond anodes (formic ∼ maleic > oxalic), thus confirming that different oxidant agents are involved at these two electrodes. Also the effect of the temperature depends on both the nature of the acid and of the anode. On the other hand, for all electrodes and substrates, higher current efficiencies were obtained when most part of the process was under the kinetic control of the oxidation reaction, i.e., when low current densities and high flow rates were imposed. A detailed study on the effect of concentration was performed. It was found that higher concentrations of carboxylic acids enhanced the current efficiency at all kinetic regimes. A comparison between potentiostatic and amperostatic electrolyses was also carried out. ISSN : 1385-8947 En ligne : http://www.sciencedirect.com/science/article/pii/S1385894711010746 [article] Oxidation of carboxylic acids in water at IrO2 – Ta2O5 and boron doped diamond anodes [texte imprimé] / Onofrio Scialdone, Auteur ; Alessandro Galia, Auteur ; Serena Randazzo, Auteur . - 2012 . - pp. 266–274. Génie chimique Langues : Anglais (eng) in Chemical engineering journal > Vol. 174 N° 1 (Octobre 2011) . - pp. 266–274 Mots-clés : Electrochemical  incineration  Carboxylic  acids  BDD  DSA  Iridium  anode  AOPs  Oxidation  of  organics Résumé : A detailed study was dedicated to the anodic oxidation of three carboxylic acids (namely, oxalic, formic and maleic acid) with the objective to evaluate in a systematic way the effect on the oxidation of carboxylic acids of numerous relevant parameters, including the nature and the concentration of the carboxylic acid, the alimentation regime (potentiostatic vs. amperostatic), the current density and the working potential values, the flowdynamic regime, the temperature and the nature of the electrode material. It was observed that the effect of some operative parameters strongly depends on the nature of the electrode and of the carboxylic acid. As an example, the efficacy of abatement decreased in the order oxalic > formic ≫ maleic at iridium anodes while an opposite trend was observed at diamond anodes (formic ∼ maleic > oxalic), thus confirming that different oxidant agents are involved at these two electrodes. Also the effect of the temperature depends on both the nature of the acid and of the anode. On the other hand, for all electrodes and substrates, higher current efficiencies were obtained when most part of the process was under the kinetic control of the oxidation reaction, i.e., when low current densities and high flow rates were imposed. A detailed study on the effect of concentration was performed. It was found that higher concentrations of carboxylic acids enhanced the current efficiency at all kinetic regimes. A comparison between potentiostatic and amperostatic electrolyses was also carried out. ISSN : 1385-8947 En ligne : http://www.sciencedirect.com/science/article/pii/S1385894711010746

Regeneration of spent bleaching earth by treatment with cethyltrimethylammonium bromide for application in elimination of acid dye / M. Mana in Chemical engineering journal, Vol. 174 N° 1 (Octobre 2011) 

Public ISBD [article]  in Chemical engineering journal > Vol. 174 N° 1 (Octobre 2011) . - pp. 275–280 Titre : Regeneration of spent bleaching earth by treatment with cethyltrimethylammonium bromide for application in elimination of acid dye Type de document : texte imprimé Auteurs : M. Mana, Auteur ; M.S. Ouali, Auteur ; L.C. De Menorval, Auteur Année de publication : 2012 Article en page(s) : pp. 275–280 Note générale : Génie chimique Langues : Anglais (eng) Mots-clés : Spent  bleaching  earth  Organoclay  Sorption  Acid  dye  Isotherms Résumé : A spent bleaching earth from an edible oil refinery has been treated with an aqueous cetyltrimethylammonium bromide solution in order to remove the edible oil impregnating the solid material and to intercalate the ammonium cation in the interlayer space of the bentonite. The obtained material was characterized by XRD and TGA-DSC and the results were compared with that of a virgin bleaching earth. The prepared organophilic bentonite was used to remove the dye acid black 10B from the aqueous solution. The removal study included the sorption isotherms, kinetics, pH and temperature effect. The maximum removal capacity obtained (100 mg g−1) was better than those of some non conventional sorbents. ISSN : 1385-8947 En ligne : http://www.sciencedirect.com/science/article/pii/S1385894711010849 [article] Regeneration of spent bleaching earth by treatment with cethyltrimethylammonium bromide for application in elimination of acid dye [texte imprimé] / M. Mana, Auteur ; M.S. Ouali, Auteur ; L.C. De Menorval, Auteur . - 2012 . - pp. 275–280. Génie chimique Langues : Anglais (eng) in Chemical engineering journal > Vol. 174 N° 1 (Octobre 2011) . - pp. 275–280 Mots-clés : Spent  bleaching  earth  Organoclay  Sorption  Acid  dye  Isotherms Résumé : A spent bleaching earth from an edible oil refinery has been treated with an aqueous cetyltrimethylammonium bromide solution in order to remove the edible oil impregnating the solid material and to intercalate the ammonium cation in the interlayer space of the bentonite. The obtained material was characterized by XRD and TGA-DSC and the results were compared with that of a virgin bleaching earth. The prepared organophilic bentonite was used to remove the dye acid black 10B from the aqueous solution. The removal study included the sorption isotherms, kinetics, pH and temperature effect. The maximum removal capacity obtained (100 mg g−1) was better than those of some non conventional sorbents. ISSN : 1385-8947 En ligne : http://www.sciencedirect.com/science/article/pii/S1385894711010849

Structural analysis of naproxen - intercalated bentonite (Unye) / A. Tabak in Chemical engineering journal, Vol. 174 N° 1 (Octobre 2011) 

Public ISBD [article]  in Chemical engineering journal > Vol. 174 N° 1 (Octobre 2011) . - pp. 281–288 Titre : Structural analysis of naproxen - intercalated bentonite (Unye) Type de document : texte imprimé Auteurs : A. Tabak, Auteur ; N. Yilmaz, Auteur ; E. Eren, Auteur Année de publication : 2012 Article en page(s) : pp. 281–288 Note générale : Génie chimique Langues : Anglais (eng) Mots-clés : Naproxen  Unye-bentonite  XRD  FTIR  TG/DTA/DSC  Surface  area Résumé : The difference in the basal spacing (8.79 Å) and a higher mass loss (6.2%) in the temperature range of 200–750 °C of naproxen-bentonite (N-bentonite) comparing to that of Unye bentonite (UB) signified the existence of thermally stable organic species in the interlamellar space of the bentonite clay. The asymmetric OCO− stretching band (1607 cm−1) of N-bentonite became stronger in the temperature interval of 100–400 °C as a result of binding via the Cdouble bond; length as m-dashO group of the ligand to exchangeable cation and/or water molecule whereas the OH bending peak of water (1633 cm−1) and the Cdouble bond; length as m-dashC stretching vibration of aromatic ring (1531 cm−1) became weaker on thermal treatment. The effect of ionic strength on the desorption of naproxen species and the related kinetic data revealed that the release mechanism at pH = 7.4 is unrestricted diffusion controlled and governed by the repulsive interactions between the bentonite surface and the negatively charged species. The pore structure characteristics of the bentonite samples corresponding to the surface area, pore volume and pore size were determined by using the conventional analysis of the nitrogen adsorption–desorption isotherms. ISSN : 1385-8947 En ligne : http://www.sciencedirect.com/science/article/pii/S1385894711010850 [article] Structural analysis of naproxen - intercalated bentonite (Unye) [texte imprimé] / A. Tabak, Auteur ; N. Yilmaz, Auteur ; E. Eren, Auteur . - 2012 . - pp. 281–288. Génie chimique Langues : Anglais (eng) in Chemical engineering journal > Vol. 174 N° 1 (Octobre 2011) . - pp. 281–288 Mots-clés : Naproxen  Unye-bentonite  XRD  FTIR  TG/DTA/DSC  Surface  area Résumé : The difference in the basal spacing (8.79 Å) and a higher mass loss (6.2%) in the temperature range of 200–750 °C of naproxen-bentonite (N-bentonite) comparing to that of Unye bentonite (UB) signified the existence of thermally stable organic species in the interlamellar space of the bentonite clay. The asymmetric OCO− stretching band (1607 cm−1) of N-bentonite became stronger in the temperature interval of 100–400 °C as a result of binding via the Cdouble bond; length as m-dashO group of the ligand to exchangeable cation and/or water molecule whereas the OH bending peak of water (1633 cm−1) and the Cdouble bond; length as m-dashC stretching vibration of aromatic ring (1531 cm−1) became weaker on thermal treatment. The effect of ionic strength on the desorption of naproxen species and the related kinetic data revealed that the release mechanism at pH = 7.4 is unrestricted diffusion controlled and governed by the repulsive interactions between the bentonite surface and the negatively charged species. The pore structure characteristics of the bentonite samples corresponding to the surface area, pore volume and pore size were determined by using the conventional analysis of the nitrogen adsorption–desorption isotherms. ISSN : 1385-8947 En ligne : http://www.sciencedirect.com/science/article/pii/S1385894711010850

Reaction mechanism of hexavalent chromium with cellulose / Shan-Li Wang in Chemical engineering journal, Vol. 174 N° 1 (Octobre 2011) 

Public ISBD [article]  in Chemical engineering journal > Vol. 174 N° 1 (Octobre 2011) . - pp.289–295 Titre : Reaction mechanism of hexavalent chromium with cellulose Type de document : texte imprimé Auteurs : Shan-Li Wang, Auteur ; Jyh-Fu Lee, Auteur Année de publication : 2012 Article en page(s) : pp.289–295 Note générale : Génie chimique Langues : Anglais (eng) Mots-clés : Cellulose  Hexavalent  chromium  Reaction  mechanism  Water  treatment Résumé : It has been suggested that lignocellulosic materials are cost-effective materials for remediation of toxic Cr(VI) pollution; however, inconsistent interpretations of the reaction mechanism are frequently found in the literature. To clarify the reaction mechanism, the reaction of Cr(VI) with individual components of lignocellulosic materials must be better understood. Thus, the purpose of this work was to investigate the reaction mechanism of Cr(VI) with cellulose, which is one of the main components of lignocellulosic materials. The Cr(VI) reaction was evaluated at pH 2 and the results showed that Cr(VI) could be reduced to Cr(III) by cellulose. As indicated by the FT-IR spectra, the hydroxyl groups in cellulose were the reactive sites for Cr(VI) reduction, giving rise to the formation of carboxyl groups. The resultant Cr(III) was either bound to cellulose or released into solution. As revealed by the Cr K-edge EXAFS of cellulose after its reaction with Cr(VI), Cr(III) was bound to cellulose by forming bidentate–mononuclear complexes with carboxyl groups, which resulted from the oxidation of hydroxyl groups. The first-order rate constant of Cr(VI) reaction with cellulose was determined to be 3.84 × 10−7 s−1 at pH 2. The slow reduction of Cr(VI) by cellulose was attributed to the existence of H-bonding networks in cellulose, which restrict the accessibility of Cr(VI) to the hydroxyl groups in cellulose. ISSN : 1385-8947 En ligne : http://www.sciencedirect.com/science/article/pii/S1385894711010898 [article] Reaction mechanism of hexavalent chromium with cellulose [texte imprimé] / Shan-Li Wang, Auteur ; Jyh-Fu Lee, Auteur . - 2012 . - pp.289–295. Génie chimique Langues : Anglais (eng) in Chemical engineering journal > Vol. 174 N° 1 (Octobre 2011) . - pp.289–295 Mots-clés : Cellulose  Hexavalent  chromium  Reaction  mechanism  Water  treatment Résumé : It has been suggested that lignocellulosic materials are cost-effective materials for remediation of toxic Cr(VI) pollution; however, inconsistent interpretations of the reaction mechanism are frequently found in the literature. To clarify the reaction mechanism, the reaction of Cr(VI) with individual components of lignocellulosic materials must be better understood. Thus, the purpose of this work was to investigate the reaction mechanism of Cr(VI) with cellulose, which is one of the main components of lignocellulosic materials. The Cr(VI) reaction was evaluated at pH 2 and the results showed that Cr(VI) could be reduced to Cr(III) by cellulose. As indicated by the FT-IR spectra, the hydroxyl groups in cellulose were the reactive sites for Cr(VI) reduction, giving rise to the formation of carboxyl groups. The resultant Cr(III) was either bound to cellulose or released into solution. As revealed by the Cr K-edge EXAFS of cellulose after its reaction with Cr(VI), Cr(III) was bound to cellulose by forming bidentate–mononuclear complexes with carboxyl groups, which resulted from the oxidation of hydroxyl groups. The first-order rate constant of Cr(VI) reaction with cellulose was determined to be 3.84 × 10−7 s−1 at pH 2. The slow reduction of Cr(VI) by cellulose was attributed to the existence of H-bonding networks in cellulose, which restrict the accessibility of Cr(VI) to the hydroxyl groups in cellulose. ISSN : 1385-8947 En ligne : http://www.sciencedirect.com/science/article/pii/S1385894711010898

a - Calcium sulfate hemihydrate preparation from FGD gypsum in recycling mixed salt solutions / Baohong Guan in Chemical engineering journal, Vol. 174 N° 1 (Octobre 2011) 

Public ISBD [article]  in Chemical engineering journal > Vol. 174 N° 1 (Octobre 2011) . - pp. 296–303 Titre : a - Calcium sulfate hemihydrate preparation from FGD gypsum in recycling mixed salt solutions Type de document : texte imprimé Auteurs : Baohong Guan, Auteur ; Yang Li, Auteur ; Hailu Fu, Auteur Année de publication : 2012 Article en page(s) : pp. 296–303 Note générale : Génie chimique Langues : Anglais (eng) Mots-clés : Alpha-calcium  sulfate  hemihydrate  FGD  gypsum  Salt  solution  recycling  Pilot  test Résumé : A pilot scale preparation of α-calcium sulfate hemihydrate (α-HH) from flue gas desulfurization (FGD) gypsum was conducted for the first time in mixed salt solutions under atmospheric pressure. The effects of salt solution recycling on the transition of α-HH from FGD gypsum were investigated by a comparison with that in laboratory scale, focusing on the dehydration rate of FGD gypsum, the crystal morphology, chemical composition and mechanical strength of the products. α-HH could be transformed from FGD gypsum in 3.5–6.0 h even though the salt solution was recycled seven times in laboratory tests and eight times in pilot tests. The product obtained in pilot scale has a purity of 95% and the α-HH crystals are mostly a prismatic morphology, with volume weighted mean diameter (D[3,4]) in the range of 52.9–84.0 μm, 2 h bending strength of 5.6–6.2 MPa and 3 d compressive strength of 15.7–25.3 MPa. The salt solution recycling achieves 56% recovery of salts in pilot scale and puts almost no negative impact on the product quality, which can be one of the best strategies to reduce the production cost. It is very likely that the process of salt solution recycling can be adopted in industry. ISSN : 1385-8947 En ligne : http://www.sciencedirect.com/science/article/pii/S1385894711010916 [article] a - Calcium sulfate hemihydrate preparation from FGD gypsum in recycling mixed salt solutions [texte imprimé] / Baohong Guan, Auteur ; Yang Li, Auteur ; Hailu Fu, Auteur . - 2012 . - pp. 296–303. Génie chimique Langues : Anglais (eng) in Chemical engineering journal > Vol. 174 N° 1 (Octobre 2011) . - pp. 296–303 Mots-clés : Alpha-calcium  sulfate  hemihydrate  FGD  gypsum  Salt  solution  recycling  Pilot  test Résumé : A pilot scale preparation of α-calcium sulfate hemihydrate (α-HH) from flue gas desulfurization (FGD) gypsum was conducted for the first time in mixed salt solutions under atmospheric pressure. The effects of salt solution recycling on the transition of α-HH from FGD gypsum were investigated by a comparison with that in laboratory scale, focusing on the dehydration rate of FGD gypsum, the crystal morphology, chemical composition and mechanical strength of the products. α-HH could be transformed from FGD gypsum in 3.5–6.0 h even though the salt solution was recycled seven times in laboratory tests and eight times in pilot tests. The product obtained in pilot scale has a purity of 95% and the α-HH crystals are mostly a prismatic morphology, with volume weighted mean diameter (D[3,4]) in the range of 52.9–84.0 μm, 2 h bending strength of 5.6–6.2 MPa and 3 d compressive strength of 15.7–25.3 MPa. The salt solution recycling achieves 56% recovery of salts in pilot scale and puts almost no negative impact on the product quality, which can be one of the best strategies to reduce the production cost. It is very likely that the process of salt solution recycling can be adopted in industry. ISSN : 1385-8947 En ligne : http://www.sciencedirect.com/science/article/pii/S1385894711010916

Ti / SnO2 – Sb2O5 – RuO2 / a - PbO2 / B - PbO2 electrodes for pollutants degradation / Yinghan Zheng in Chemical engineering journal, Vol. 174 N° 1 (Octobre 2011) 

Public ISBD [article]  in Chemical engineering journal > Vol. 174 N° 1 (Octobre 2011) . - pp.304–309 Titre : Ti / SnO2 – Sb2O5 – RuO2 / a - PbO2 / B - PbO2 electrodes for pollutants degradation Type de document : texte imprimé Auteurs : Yinghan Zheng, Auteur ; Wenqiu Su, Auteur ; Shengying Chen, Auteur Année de publication : 2012 Article en page(s) : pp.304–309 Note générale : Génie chimique Langues : Anglais (eng) Mots-clés : PbO2  electrodes  Wastewater  Electrochemical  degradation  Phenol  4-Chlorophenol Résumé : The SnO2–Sb2O5–RuO2, α-PbO2 and β-PbO2 films were successfully deposited on Ti nets using thermal deposition and electrodeposition methods. It was found that the SnO2–Sb2O5–RuO2 interlayer played a very important role in enhancing the PbO2 films electrodeposition. The Ti/SnO2–Sb2O5–RuO2/α-PbO2/β-PbO2 electrodes obtained were superior not only in electrochemical stability but also in activity for pollutants degradation. The lifetime reached 59 h under the accelerated life test conditions at a current density of 4 A/cm2 in 0.5 M H2SO4 solution. The COD removal and average current efficiencies were about 94% and 53% for degrading 500 mg/L phenol at a current density of 100 A/m2, and about 82% and 25% for degrading 1 mM 4-chlorophenol at 200 A/m2. ISSN : 1385-8947 En ligne : http://www.sciencedirect.com/science/article/pii/S138589471101093X [article] Ti / SnO2 – Sb2O5 – RuO2 / a - PbO2 / B - PbO2 electrodes for pollutants degradation [texte imprimé] / Yinghan Zheng, Auteur ; Wenqiu Su, Auteur ; Shengying Chen, Auteur . - 2012 . - pp.304–309. Génie chimique Langues : Anglais (eng) in Chemical engineering journal > Vol. 174 N° 1 (Octobre 2011) . - pp.304–309 Mots-clés : PbO2  electrodes  Wastewater  Electrochemical  degradation  Phenol  4-Chlorophenol Résumé : The SnO2–Sb2O5–RuO2, α-PbO2 and β-PbO2 films were successfully deposited on Ti nets using thermal deposition and electrodeposition methods. It was found that the SnO2–Sb2O5–RuO2 interlayer played a very important role in enhancing the PbO2 films electrodeposition. The Ti/SnO2–Sb2O5–RuO2/α-PbO2/β-PbO2 electrodes obtained were superior not only in electrochemical stability but also in activity for pollutants degradation. The lifetime reached 59 h under the accelerated life test conditions at a current density of 4 A/cm2 in 0.5 M H2SO4 solution. The COD removal and average current efficiencies were about 94% and 53% for degrading 500 mg/L phenol at a current density of 100 A/m2, and about 82% and 25% for degrading 1 mM 4-chlorophenol at 200 A/m2. ISSN : 1385-8947 En ligne : http://www.sciencedirect.com/science/article/pii/S138589471101093X

Immobilization of vegetable tannins on tannery chrome shavings and their use for the removal of hexavalent chromium from contaminated water / L. Chabaane in Chemical engineering journal, Vol. 174 N° 1 (Octobre 2011) 

Public ISBD [article]  in Chemical engineering journal > Vol. 174 N° 1 (Octobre 2011) . - pp.310-317 Titre : Immobilization of vegetable tannins on tannery chrome shavings and their use for the removal of hexavalent chromium from contaminated water Type de document : texte imprimé Auteurs : L. Chabaane, Auteur ; S. Tahiri, Auteur Année de publication : 2012 Article en page(s) : pp.310-317 Note générale : Génie chimique Langues : Anglais (eng) Mots-clés : Immobilization  Tannins  Chrome  shavings  Hexavalent  chromium  Adsorption Résumé : Chestnut (C) and mimosa (M) tannins immobilized on chrome shavings (CS) as an adsorbent have been proposed to be an efficient and economical alternative in hexavalent chromium removal from aqueous solutions. The adsorption of hexavalent chromium onto chrome shavings-tannin (CS-T) adsorbents was performed using batch equilibrium technique at 25+/-2^oC. The effect of pH is highly important especially in the case of high concentrations of hexavalent chromium. The maximum chromium uptake was obtained at pH 4. Two hours of contact time are enough to reach equilibrium. Sorption of chromium on CS-T was found to follow a pseudo-second order kinetic model (with correlation coefficients greater than 0.999). The adsorption equilibrium data fitted the Langmuir model well. The maximum adsorption capacity, of dry immobilized tannin adsorbent with 11.6% polyphenol, reached 42mgCr/g and 38mgCr/g in the case of chestnut and mimosa tannins, respectively. ISSN : 1385-8947 En ligne : http://pubget.com/paper/pgtmp_469cdf51c486c0777e69c04e04029e9e [article] Immobilization of vegetable tannins on tannery chrome shavings and their use for the removal of hexavalent chromium from contaminated water [texte imprimé] / L. Chabaane, Auteur ; S. Tahiri, Auteur . - 2012 . - pp.310-317. Génie chimique Langues : Anglais (eng) in Chemical engineering journal > Vol. 174 N° 1 (Octobre 2011) . - pp.310-317 Mots-clés : Immobilization  Tannins  Chrome  shavings  Hexavalent  chromium  Adsorption Résumé : Chestnut (C) and mimosa (M) tannins immobilized on chrome shavings (CS) as an adsorbent have been proposed to be an efficient and economical alternative in hexavalent chromium removal from aqueous solutions. The adsorption of hexavalent chromium onto chrome shavings-tannin (CS-T) adsorbents was performed using batch equilibrium technique at 25+/-2^oC. The effect of pH is highly important especially in the case of high concentrations of hexavalent chromium. The maximum chromium uptake was obtained at pH 4. Two hours of contact time are enough to reach equilibrium. Sorption of chromium on CS-T was found to follow a pseudo-second order kinetic model (with correlation coefficients greater than 0.999). The adsorption equilibrium data fitted the Langmuir model well. The maximum adsorption capacity, of dry immobilized tannin adsorbent with 11.6% polyphenol, reached 42mgCr/g and 38mgCr/g in the case of chestnut and mimosa tannins, respectively. ISSN : 1385-8947 En ligne : http://pubget.com/paper/pgtmp_469cdf51c486c0777e69c04e04029e9e

The benefit of glass bead supports for efficient gas phase photocatalysis / Sammy W. Verbruggen in Chemical engineering journal, Vol. 174 N° 1 (Octobre 2011) 

Public ISBD [article]  in Chemical engineering journal > Vol. 174 N° 1 (Octobre 2011) . - pp.318–325 Titre : The benefit of glass bead supports for efficient gas phase photocatalysis : Case study of a commercial and a synthesised photocatalyst Type de document : texte imprimé Auteurs : Sammy W. Verbruggen, Auteur ; Stefan Ribbens, Auteur ; Tom Tytgat, Auteur Année de publication : 2012 Article en page(s) : pp.318–325 Note générale : Génie chimique Langues : Anglais (eng) Mots-clés : Photocatalysis  Titanium  dioxide  (TiO2)  Coating  Ethylene  Trititanate  nanotubes Résumé : In the field of photocatalytic air purification, the immobilisation of catalyst particles on support surfaces without loss of photon efficiency is an important challenge. Therefore, an immobilisation method involving a one-step suspension coating of pre-synthesised photocatalysts on glass beads was applied. The various benefits are exemplified in the gas phase photodegradation of ethylene. Coating of glass beads is easy, fast, cheap and offers a more efficient alternative to bulk catalyst pellets. Furthermore, this coating procedure allows to use porous, pre-synthesised catalysts to their full potential, as the surface area and morphology of the initial powder is barely altered after coating, in strong contrast to pelletising. With this technique it became possible to study the gas phase photocatalytic activity of commercial titanium dioxide, trititanate nanotubes and mixed phase anatase/trititanate nanotubes in a packed bed reactor towards the degradation of ethylene without changing the catalyst properties. Coating of glass beads with the photocatalyst revealed the superior activity of the as-prepared nanotubes, compared to TiO2 Aerolyst® 7710 in gaseous phase. ISSN : 1385-8947 En ligne : http://www.sciencedirect.com/science/article/pii/S1385894711010965 [article] The benefit of glass bead supports for efficient gas phase photocatalysis : Case study of a commercial and a synthesised photocatalyst [texte imprimé] / Sammy W. Verbruggen, Auteur ; Stefan Ribbens, Auteur ; Tom Tytgat, Auteur . - 2012 . - pp.318–325. Génie chimique Langues : Anglais (eng) in Chemical engineering journal > Vol. 174 N° 1 (Octobre 2011) . - pp.318–325 Mots-clés : Photocatalysis  Titanium  dioxide  (TiO2)  Coating  Ethylene  Trititanate  nanotubes Résumé : In the field of photocatalytic air purification, the immobilisation of catalyst particles on support surfaces without loss of photon efficiency is an important challenge. Therefore, an immobilisation method involving a one-step suspension coating of pre-synthesised photocatalysts on glass beads was applied. The various benefits are exemplified in the gas phase photodegradation of ethylene. Coating of glass beads is easy, fast, cheap and offers a more efficient alternative to bulk catalyst pellets. Furthermore, this coating procedure allows to use porous, pre-synthesised catalysts to their full potential, as the surface area and morphology of the initial powder is barely altered after coating, in strong contrast to pelletising. With this technique it became possible to study the gas phase photocatalytic activity of commercial titanium dioxide, trititanate nanotubes and mixed phase anatase/trititanate nanotubes in a packed bed reactor towards the degradation of ethylene without changing the catalyst properties. Coating of glass beads with the photocatalyst revealed the superior activity of the as-prepared nanotubes, compared to TiO2 Aerolyst® 7710 in gaseous phase. ISSN : 1385-8947 En ligne : http://www.sciencedirect.com/science/article/pii/S1385894711010965

Microwave - assisted preparation of bamboo charcoal - based iron - containing adsorbents for Cr(VI) removal / X.J. Wang in Chemical engineering journal, Vol. 174 N° 1 (Octobre 2011) 

Public ISBD [article]  in Chemical engineering journal > Vol. 174 N° 1 (Octobre 2011) . - pp. 326–332 Titre : Microwave - assisted preparation of bamboo charcoal - based iron - containing adsorbents for Cr(VI) removal Type de document : texte imprimé Auteurs : X.J. Wang, Auteur ; Y. Wang, Auteur ; X. Wang, Auteur Année de publication : 2012 Article en page(s) : pp. 326–332 Note générale : Génie chimique Langues : Anglais (eng) Mots-clés : Bamboo  charcoal  Adsorption  Heavy  metal  Drinking  water Résumé : Bamboo charcoal-based, iron-containing adsorbent (Fe–BC) was developed by using bamboo charcoal (BC) as a supporting medium for ferric iron that was impregnated by Fe2(SO4)3 and H2SO4 simultaneous treatment, followed by microwave heating. The low-cost composite was characterized and used as an adsorbent for Cr(VI) removal from water. The results showed that the BET specific surface area, total pore volume, and average mesoporous diameter of Fe–BC all decreased with iron impregnation. As an adsorbent, Fe–BC showed an excellent adsorption capability for Cr(VI), the adsorption process followed the Langmuir model, and the adsorption kinetic followed pseudo-second-order model. The adsorption of Cr(VI) onto Fe–BC was spontaneous and exothermic under the studied conditions. Column adsorption experiment with Fe–BC showed that Cr(VI) could be removed to below 0.05 mg/L within 360 bed volumes at empty bed contact time 2 min when the groundwater containing approximately 0.12 mg/L of Cr(VI) was treated. The spent Fe–BC adsorbent could be readily regenerated for reuse by dilute NaOH solution. ISSN : 1385-8947 En ligne : http://www.sciencedirect.com/science/article/pii/S1385894711011028 [article] Microwave - assisted preparation of bamboo charcoal - based iron - containing adsorbents for Cr(VI) removal [texte imprimé] / X.J. Wang, Auteur ; Y. Wang, Auteur ; X. Wang, Auteur . - 2012 . - pp. 326–332. Génie chimique Langues : Anglais (eng) in Chemical engineering journal > Vol. 174 N° 1 (Octobre 2011) . - pp. 326–332 Mots-clés : Bamboo  charcoal  Adsorption  Heavy  metal  Drinking  water Résumé : Bamboo charcoal-based, iron-containing adsorbent (Fe–BC) was developed by using bamboo charcoal (BC) as a supporting medium for ferric iron that was impregnated by Fe2(SO4)3 and H2SO4 simultaneous treatment, followed by microwave heating. The low-cost composite was characterized and used as an adsorbent for Cr(VI) removal from water. The results showed that the BET specific surface area, total pore volume, and average mesoporous diameter of Fe–BC all decreased with iron impregnation. As an adsorbent, Fe–BC showed an excellent adsorption capability for Cr(VI), the adsorption process followed the Langmuir model, and the adsorption kinetic followed pseudo-second-order model. The adsorption of Cr(VI) onto Fe–BC was spontaneous and exothermic under the studied conditions. Column adsorption experiment with Fe–BC showed that Cr(VI) could be removed to below 0.05 mg/L within 360 bed volumes at empty bed contact time 2 min when the groundwater containing approximately 0.12 mg/L of Cr(VI) was treated. The spent Fe–BC adsorbent could be readily regenerated for reuse by dilute NaOH solution. ISSN : 1385-8947 En ligne : http://www.sciencedirect.com/science/article/pii/S1385894711011028

Combustion of reactive solutions impregnated into a cellulose carrier / E.M. Lennon in Chemical engineering journal, Vol. 174 N° 1 (Octobre 2011) 

Public ISBD [article]  in Chemical engineering journal > Vol. 174 N° 1 (Octobre 2011) . - pp.333–340 Titre : Combustion of reactive solutions impregnated into a cellulose carrier : Modeling of two combustion fronts Type de document : texte imprimé Auteurs : E.M. Lennon, Auteur ; M.C. Tanzy, Auteur ; V.A. Volpert, Auteur Année de publication : 2012 Article en page(s) : pp.333–340 Note générale : Génie chimique Langues : Anglais (eng) Mots-clés : Combustion  synthesis  Combustion  modeling  Nanomaterial  synthesis  Reaction  fronts Résumé : We develop and solve a novel model for the combustion of reactive solutions impregnated into a cellulose carrier. This procedure has been shown to be effective in the synthesis of metallic oxides with a nanoscale microstructure, which are suitable for catalyst applications. The model involves three reactions, (i) combustion of the carrier matrix, (ii) an endothermic reaction related to the decomposition or gasification of the synthesis reaction precursors and (iii) the exothermic oxide synthesis reaction. This model is shown to provide qualitative agreement with experimental observations. A parametric study of the model demonstrates that increasing the heat released via the leading cellulose burning reaction (i) is most favorable in terms of increasing the reaction yield and providing conditions for smaller size of the synthesized material. ISSN : 1385-8947 En ligne : http://www.sciencedirect.com/science/article/pii/S1385894711004530 [article] Combustion of reactive solutions impregnated into a cellulose carrier : Modeling of two combustion fronts [texte imprimé] / E.M. Lennon, Auteur ; M.C. Tanzy, Auteur ; V.A. Volpert, Auteur . - 2012 . - pp.333–340. Génie chimique Langues : Anglais (eng) in Chemical engineering journal > Vol. 174 N° 1 (Octobre 2011) . - pp.333–340 Mots-clés : Combustion  synthesis  Combustion  modeling  Nanomaterial  synthesis  Reaction  fronts Résumé : We develop and solve a novel model for the combustion of reactive solutions impregnated into a cellulose carrier. This procedure has been shown to be effective in the synthesis of metallic oxides with a nanoscale microstructure, which are suitable for catalyst applications. The model involves three reactions, (i) combustion of the carrier matrix, (ii) an endothermic reaction related to the decomposition or gasification of the synthesis reaction precursors and (iii) the exothermic oxide synthesis reaction. This model is shown to provide qualitative agreement with experimental observations. A parametric study of the model demonstrates that increasing the heat released via the leading cellulose burning reaction (i) is most favorable in terms of increasing the reaction yield and providing conditions for smaller size of the synthesized material. ISSN : 1385-8947 En ligne : http://www.sciencedirect.com/science/article/pii/S1385894711004530

CPFD simulation of a fast fluidized bed steam coal gasifier feeding section / Alireza Abbasi in Chemical engineering journal, Vol. 174 N° 1 (Octobre 2011) 

Public ISBD [article]  in Chemical engineering journal > Vol. 174 N° 1 (Octobre 2011) . - pp.341-350 Titre : CPFD simulation of a fast fluidized bed steam coal gasifier feeding section Type de document : texte imprimé Auteurs : Alireza Abbasi, Auteur ; Paul E. Ege, Auteur ; Hugo I. De Lasa, Auteur Année de publication : 2012 Article en page(s) : pp.341-350 Note générale : Génie chimique Langues : Anglais (eng) Mots-clés : Coal  gasification  Fluidized  beds  Computational  particle  fluid  dynamics  Suspension  chocking Résumé : Coal gasification in fluidized beds is a process that can be strongly influenced by gas–solid suspension flow patterns. Fast fluidized beds can be designed to maximize coal gasification yields providing an optimum syngas composition with minimum operational upsets. In order to accomplish this, a comprehensive model for steam coal gasification is valuable. With this end, a 2D CPFD (computational particle fluid dynamics) dynamic model is considered in the present study. The proposed model uses a Lagrangian–Eulerian approach and describes the flow patterns in the gasifier feeding section, as well as the local particle velocities, particle solid fractions and gas composition. As a reference and for comparison, an ideal PFR (plug flow reactor) model is also considered. It is found that compositions from the 2D CPFD model provide close gas compositions with respect to the PFR. It is observed that the 2D CPFD model is valuable for predicting particle flows in the feeding near region keeping it unaffected by fast fluidized bed upsets such as suspension chocking. It is also found that the 2D CPFD model is particularly useful for describing fast fluidized beds operation involving significant amounts of rich ash recycled feeds. ISSN : 1385-8947 En ligne : http://www.sciencedirect.com/science/article/pii/S1385894711009752 [article] CPFD simulation of a fast fluidized bed steam coal gasifier feeding section [texte imprimé] / Alireza Abbasi, Auteur ; Paul E. Ege, Auteur ; Hugo I. De Lasa, Auteur . - 2012 . - pp.341-350. Génie chimique Langues : Anglais (eng) in Chemical engineering journal > Vol. 174 N° 1 (Octobre 2011) . - pp.341-350 Mots-clés : Coal  gasification  Fluidized  beds  Computational  particle  fluid  dynamics  Suspension  chocking Résumé : Coal gasification in fluidized beds is a process that can be strongly influenced by gas–solid suspension flow patterns. Fast fluidized beds can be designed to maximize coal gasification yields providing an optimum syngas composition with minimum operational upsets. In order to accomplish this, a comprehensive model for steam coal gasification is valuable. With this end, a 2D CPFD (computational particle fluid dynamics) dynamic model is considered in the present study. The proposed model uses a Lagrangian–Eulerian approach and describes the flow patterns in the gasifier feeding section, as well as the local particle velocities, particle solid fractions and gas composition. As a reference and for comparison, an ideal PFR (plug flow reactor) model is also considered. It is found that compositions from the 2D CPFD model provide close gas compositions with respect to the PFR. It is observed that the 2D CPFD model is valuable for predicting particle flows in the feeding near region keeping it unaffected by fast fluidized bed upsets such as suspension chocking. It is also found that the 2D CPFD model is particularly useful for describing fast fluidized beds operation involving significant amounts of rich ash recycled feeds. ISSN : 1385-8947 En ligne : http://www.sciencedirect.com/science/article/pii/S1385894711009752

Effect of CdS distribution on the photocatalytic performance of resin - CdS nanocomposites / Yingmei Xie in Chemical engineering journal, Vol. 174 N° 1 (Octobre 2011) 

Public ISBD [article]  in Chemical engineering journal > Vol. 174 N° 1 (Octobre 2011) . - pp. 351–356 Titre : Effect of CdS distribution on the photocatalytic performance of resin - CdS nanocomposites Type de document : texte imprimé Auteurs : Yingmei Xie, Auteur ; Shujuan Zhang, Auteur ; Bingcai Pan, Auteur Année de publication : 2012 Article en page(s) : pp. 351–356 Note générale : Génie chimique Langues : Anglais (eng) Mots-clés : Shell  thickness  Shell  density  Rhodamin  B  D201-CdS Résumé : A nanocomposite, D201-CdS, made by depositing CdS nanoparticles on a resin support (D201) was found to be a promising photocatalyst with visible light response. To elucidate the structure-activity relationship, a set of D201-CdS nanocomposites varying in CdS amount and distribution were prepared by adjusting the concentration of sulfide anion and the precipitation time. The maximum compressive strength of the nanocomposites increased first with the loading of CdS and then declined with the further increase of CdS. There was a valid shell thickness of CdS due to the limitation of visible light in penetration through the resin matrix. Within a certain range of shell thickness, the increase of shell density of CdS would be favorable for the purpose of photodegradation. The shell density could be easily tuned by adjusting the fabrication condition employed in this work, which is an important merit for the potential production and application. ISSN : 1385-8947 En ligne : http://www.sciencedirect.com/science/article/pii/S1385894711010643 [article] Effect of CdS distribution on the photocatalytic performance of resin - CdS nanocomposites [texte imprimé] / Yingmei Xie, Auteur ; Shujuan Zhang, Auteur ; Bingcai Pan, Auteur . - 2012 . - pp. 351–356. Génie chimique Langues : Anglais (eng) in Chemical engineering journal > Vol. 174 N° 1 (Octobre 2011) . - pp. 351–356 Mots-clés : Shell  thickness  Shell  density  Rhodamin  B  D201-CdS Résumé : A nanocomposite, D201-CdS, made by depositing CdS nanoparticles on a resin support (D201) was found to be a promising photocatalyst with visible light response. To elucidate the structure-activity relationship, a set of D201-CdS nanocomposites varying in CdS amount and distribution were prepared by adjusting the concentration of sulfide anion and the precipitation time. The maximum compressive strength of the nanocomposites increased first with the loading of CdS and then declined with the further increase of CdS. There was a valid shell thickness of CdS due to the limitation of visible light in penetration through the resin matrix. Within a certain range of shell thickness, the increase of shell density of CdS would be favorable for the purpose of photodegradation. The shell density could be easily tuned by adjusting the fabrication condition employed in this work, which is an important merit for the potential production and application. ISSN : 1385-8947 En ligne : http://www.sciencedirect.com/science/article/pii/S1385894711010643

Tuning optimal - robust linear MIMO controllers of chemical reactors by using Pareto optimality / J. Carrillo-Ahumada in Chemical engineering journal, Vol. 174 N° 1 (Octobre 2011) 

Public ISBD [article]  in Chemical engineering journal > Vol. 174 N° 1 (Octobre 2011) . - pp.357–367 Titre : Tuning optimal - robust linear MIMO controllers of chemical reactors by using Pareto optimality Type de document : texte imprimé Auteurs : J. Carrillo-Ahumada, Auteur ; G.C. Rodríguez-Jimenes, Auteur ; M.A. García-Alvarado, Auteur Année de publication : 2012 Article en page(s) : pp.357–367 Note générale : Génie chimique Langues : Anglais (eng) Mots-clés : Process  control  Robust  control  Chemical  reactors  Dynamic  simulation  Optimization  Pareto  optimality Résumé : Pareto optimality was introduced in order to find the better equilibrium between performance and robustness of linear controllers by the simultaneous minimization of the quadratic-error and quadratic-control functions integrals. The Pareto optimization problem was solved setting the characteristic matrix eigenvalues in the region of left complex semi plane where |Im/Re| < 1 as constraint. 2D Pareto fronts were built with the quadratic-error function integral vs. quadratic-control function integral. The proposed method was applied for tuning linear controllers of three chemical reactors with different kinetic equations and mix patterns. In the three situations, the Pareto optimality procedure improved the controllers’ performance and robustness with respect to controllers previously tuned by different methods. ISSN : 1385-8947 En ligne : http://www.sciencedirect.com/science/article/pii/S1385894711010655 [article] Tuning optimal - robust linear MIMO controllers of chemical reactors by using Pareto optimality [texte imprimé] / J. Carrillo-Ahumada, Auteur ; G.C. Rodríguez-Jimenes, Auteur ; M.A. García-Alvarado, Auteur . - 2012 . - pp.357–367. Génie chimique Langues : Anglais (eng) in Chemical engineering journal > Vol. 174 N° 1 (Octobre 2011) . - pp.357–367 Mots-clés : Process  control  Robust  control  Chemical  reactors  Dynamic  simulation  Optimization  Pareto  optimality Résumé : Pareto optimality was introduced in order to find the better equilibrium between performance and robustness of linear controllers by the simultaneous minimization of the quadratic-error and quadratic-control functions integrals. The Pareto optimization problem was solved setting the characteristic matrix eigenvalues in the region of left complex semi plane where |Im/Re| < 1 as constraint. 2D Pareto fronts were built with the quadratic-error function integral vs. quadratic-control function integral. The proposed method was applied for tuning linear controllers of three chemical reactors with different kinetic equations and mix patterns. In the three situations, the Pareto optimality procedure improved the controllers’ performance and robustness with respect to controllers previously tuned by different methods. ISSN : 1385-8947 En ligne : http://www.sciencedirect.com/science/article/pii/S1385894711010655

Investigating the effect of pristine and modified silica nanoparticles on the kinetics of methyl methacrylate polymerization / Mehdi Salami-Kalajahi in Chemical engineering journal, Vol. 174 N° 1 (Octobre 2011) 

Public ISBD [article]  in Chemical engineering journal > Vol. 174 N° 1 (Octobre 2011) . - pp.368–375 Titre : Investigating the effect of pristine and modified silica nanoparticles on the kinetics of methyl methacrylate polymerization Type de document : texte imprimé Auteurs : Mehdi Salami-Kalajahi, Auteur ; Vahid Haddadi-Asl, Auteur ; Saeid Rahimi-Razin, Auteur Année de publication : 2012 Article en page(s) : pp.368–375 Note générale : Génie chimique Langues : Anglais (eng) Mots-clés : In  situ  polymerization  Kinetics  Rate  coefficient  Poly(methyl  methacrylate)  Silica  nanoparticles Résumé : To study the effect of silica nanoparticles on the kinetics of methyl methacrylate free radical polymerization, a number of batch polymerizations were performed using pristine and methacrylate-modified silica nanoparticles at 75 °C. In addition, effect of temperature was investigated on the kinetics of polymerization with 1 wt% loading of pristine nanoparticles. Monomer conversion, reaction rate, molecular weight and polydispersity index (PDI) of each polymerization were monitored during polymerization. According to results, no considerable change was obtained on the polymerization kinetics by introduction of any type of nanoparticles, while there is an optimum loading value in which the polymerization rate reaches its maximum level. A similar trend is observed for molecular weight of free chains; however, increasing silica content results in increased PDI values. Also, polymerizations rate is slower for batches containing modified nanoparticles. For chains which are grafted on the surface of modified nanoparticles, molecular weight and PDI values increase by increasing nanoparticle content. ISSN : 1385-8947 En ligne : http://www.sciencedirect.com/science/article/pii/S1385894711010667 [article] Investigating the effect of pristine and modified silica nanoparticles on the kinetics of methyl methacrylate polymerization [texte imprimé] / Mehdi Salami-Kalajahi, Auteur ; Vahid Haddadi-Asl, Auteur ; Saeid Rahimi-Razin, Auteur . - 2012 . - pp.368–375. Génie chimique Langues : Anglais (eng) in Chemical engineering journal > Vol. 174 N° 1 (Octobre 2011) . - pp.368–375 Mots-clés : In  situ  polymerization  Kinetics  Rate  coefficient  Poly(methyl  methacrylate)  Silica  nanoparticles Résumé : To study the effect of silica nanoparticles on the kinetics of methyl methacrylate free radical polymerization, a number of batch polymerizations were performed using pristine and methacrylate-modified silica nanoparticles at 75 °C. In addition, effect of temperature was investigated on the kinetics of polymerization with 1 wt% loading of pristine nanoparticles. Monomer conversion, reaction rate, molecular weight and polydispersity index (PDI) of each polymerization were monitored during polymerization. According to results, no considerable change was obtained on the polymerization kinetics by introduction of any type of nanoparticles, while there is an optimum loading value in which the polymerization rate reaches its maximum level. A similar trend is observed for molecular weight of free chains; however, increasing silica content results in increased PDI values. Also, polymerizations rate is slower for batches containing modified nanoparticles. For chains which are grafted on the surface of modified nanoparticles, molecular weight and PDI values increase by increasing nanoparticle content. ISSN : 1385-8947 En ligne : http://www.sciencedirect.com/science/article/pii/S1385894711010667

Synthesis of Co oxide doped carbon aerogel catalyst and catalytic performance in heterogeneous oxidation of phenol in water / Yasnessya Hardjono in Chemical engineering journal, Vol. 174 N° 1 (Octobre 2011) 

Public ISBD [article]  in Chemical engineering journal > Vol. 174 N° 1 (Octobre 2011) . - pp.376–382 Titre : Synthesis of Co oxide doped carbon aerogel catalyst and catalytic performance in heterogeneous oxidation of phenol in water Type de document : texte imprimé Auteurs : Yasnessya Hardjono, Auteur ; Hongqi Sun, Auteur ; Huyong Tian, Auteur Année de publication : 2012 Article en page(s) : pp.376–382 Note générale : Génie chimique Langues : Anglais (eng) Mots-clés : Phenol  Carbon  aerogel  Cobalt  oxide  Heterogeneous  oxidation  Oxone Résumé : Co oxide doped carbon aerogel (Co/CA) was prepared, characterised by several techniques, and tested for heterogeneous oxidation of phenol in aqueous solution using oxone as an oxidant. For a comparison, homogeneous oxidation of phenol in Co2+/oxone was also investigated. It was found that homogeneous oxidation of phenol using Co2+/oxone was more effective than Co2+/H2O2 and homogeneous oxidation was faster than heterogeneous Co/CA–oxone. Heterogeneous oxidation of phenol in Co/CA–oxone system followed first order kinetics and the activation energy of the heterogeneous system was estimated to be 62.9 kJ/mol. Several factors influencing phenol degradation in the heterogeneous oxidation were studied. Co/CA loading played a more important role in phenol degradation than oxone concentration, and the presence of other organics in solution resulted in a lower phenol oxidation. ISSN : 1385-8947 En ligne : http://www.sciencedirect.com/science/article/pii/S1385894711010679# [article] Synthesis of Co oxide doped carbon aerogel catalyst and catalytic performance in heterogeneous oxidation of phenol in water [texte imprimé] / Yasnessya Hardjono, Auteur ; Hongqi Sun, Auteur ; Huyong Tian, Auteur . - 2012 . - pp.376–382. Génie chimique Langues : Anglais (eng) in Chemical engineering journal > Vol. 174 N° 1 (Octobre 2011) . - pp.376–382 Mots-clés : Phenol  Carbon  aerogel  Cobalt  oxide  Heterogeneous  oxidation  Oxone Résumé : Co oxide doped carbon aerogel (Co/CA) was prepared, characterised by several techniques, and tested for heterogeneous oxidation of phenol in aqueous solution using oxone as an oxidant. For a comparison, homogeneous oxidation of phenol in Co2+/oxone was also investigated. It was found that homogeneous oxidation of phenol using Co2+/oxone was more effective than Co2+/H2O2 and homogeneous oxidation was faster than heterogeneous Co/CA–oxone. Heterogeneous oxidation of phenol in Co/CA–oxone system followed first order kinetics and the activation energy of the heterogeneous system was estimated to be 62.9 kJ/mol. Several factors influencing phenol degradation in the heterogeneous oxidation were studied. Co/CA loading played a more important role in phenol degradation than oxone concentration, and the presence of other organics in solution resulted in a lower phenol oxidation. ISSN : 1385-8947 En ligne : http://www.sciencedirect.com/science/article/pii/S1385894711010679#

Development of a new method for investigating the mechanisms of solid particle dissolution in nitric acid media / Céline Delwaulle in Chemical engineering journal, Vol. 174 N° 1 (Octobre 2011) 

Public ISBD [article]  in Chemical engineering journal > Vol. 174 N° 1 (Octobre 2011) . - pp. 383–389 Titre : Development of a new method for investigating the mechanisms of solid particle dissolution in nitric acid media : Millifluidic study using fluorescent indicators Type de document : texte imprimé Auteurs : Céline Delwaulle, Auteur ; Alastair Magnaldo, Auteur ; Andrea Salvatores, Auteur Année de publication : 2012 Article en page(s) : pp. 383–389 Note générale : Génie chimique Langues : Anglais (eng) Mots-clés : Dissolution  In  situ  monitoring  Reaction  interface  Gas  bubbles  Nitric  acid  Kinetics  Miniaturization Résumé : A key step in existing industrial recycling processes for spent nuclear fuel, after cutting up the spent fuel assemblies, is the continuous dissolution of uranium dioxide in a dissolver containing concentrated nitric acid. The purpose of this study is to enhance our understanding of the phenomena governing the oxide behavior during dissolution, and to acquire new experimental data suitable for modeling and optimizing spent fuel dissolution. The approach adopted involved small scale experiments, which are indispensable for observing, understanding and modeling the phenomena occurring at the solid/liquid interface which control the dissolution reaction. A millifluidic reactor of about 1 mL was developed for the continuous dissolution of millimeter or submillimeter solid particles in a nitric acid stream. New experimental and analytical monitoring techniques were used (observation at the interface by confocal microscopy and epifluorescence, tracking of the species involved, pH monitoring at the interface by fluorometry). Qualification and experimental implementation of these techniques were first conducted on a nonradioactive surrogate, copper. These observations were used to better understand and quantify continuously and in situ the material dissolution mechanisms and the pH variation at the interface, as well as providing data on the behavior of the off-gases. Intermediate species favorable to the reaction were identified, and made it possible to quantify the coupling between hydrodynamics and dissolution kinetics. We were also able to obtain a pH map of the reaction interface, which is very difficult to implement for this type of reaction in corrosive media. ISSN : 1385-8947 En ligne : http://www.sciencedirect.com/science/article/pii/S1385894711010710 [article] Development of a new method for investigating the mechanisms of solid particle dissolution in nitric acid media : Millifluidic study using fluorescent indicators [texte imprimé] / Céline Delwaulle, Auteur ; Alastair Magnaldo, Auteur ; Andrea Salvatores, Auteur . - 2012 . - pp. 383–389. Génie chimique Langues : Anglais (eng) in Chemical engineering journal > Vol. 174 N° 1 (Octobre 2011) . - pp. 383–389 Mots-clés : Dissolution  In  situ  monitoring  Reaction  interface  Gas  bubbles  Nitric  acid  Kinetics  Miniaturization Résumé : A key step in existing industrial recycling processes for spent nuclear fuel, after cutting up the spent fuel assemblies, is the continuous dissolution of uranium dioxide in a dissolver containing concentrated nitric acid. The purpose of this study is to enhance our understanding of the phenomena governing the oxide behavior during dissolution, and to acquire new experimental data suitable for modeling and optimizing spent fuel dissolution. The approach adopted involved small scale experiments, which are indispensable for observing, understanding and modeling the phenomena occurring at the solid/liquid interface which control the dissolution reaction. A millifluidic reactor of about 1 mL was developed for the continuous dissolution of millimeter or submillimeter solid particles in a nitric acid stream. New experimental and analytical monitoring techniques were used (observation at the interface by confocal microscopy and epifluorescence, tracking of the species involved, pH monitoring at the interface by fluorometry). Qualification and experimental implementation of these techniques were first conducted on a nonradioactive surrogate, copper. These observations were used to better understand and quantify continuously and in situ the material dissolution mechanisms and the pH variation at the interface, as well as providing data on the behavior of the off-gases. Intermediate species favorable to the reaction were identified, and made it possible to quantify the coupling between hydrodynamics and dissolution kinetics. We were also able to obtain a pH map of the reaction interface, which is very difficult to implement for this type of reaction in corrosive media. ISSN : 1385-8947 En ligne : http://www.sciencedirect.com/science/article/pii/S1385894711010710

NO (or NH3) + O2 adsorption on fluorine-doped vanadia/titania and its role in the mechanism of a two - step process characterized by EPR / Qin Zhong in Chemical engineering journal, Vol. 174 N° 1 (Octobre 2011) 

Public ISBD [article]  in Chemical engineering journal > Vol. 174 N° 1 (Octobre 2011) . - pp.390–395 Titre : NO (or NH3) + O2 adsorption on fluorine-doped vanadia/titania and its role in the mechanism of a two - step process characterized by EPR Type de document : texte imprimé Auteurs : Qin Zhong, Auteur ; Tianjiao Zhang, Auteur ; Yuntao Li, Auteur Année de publication : 2012 Article en page(s) : pp.390–395 Note générale : Génie chimique Langues : Anglais (eng) Mots-clés : Low-temperature  selective  catalytic  reduction  F-doping  Vanadia/titania  Superoxide  ions Résumé : This study aimed at elucidating a two-step process of the low-temperature selective catalytic reduction (SCR) reaction. The data were collected through studying the EPR signal of NO (or NH3) + O2 adsorption on fluorine-doped vanadia/titania and vanadia/titania catalysts used for SCR reaction, as well as the impact of SO2 and H2O added to the gas mixtures. The EPR experiments provided a new method to explain the SCR reaction, which were associated with NO (NH3) + O2 reacting systems and had been inferred step by step. In summary, the first step of the two-step process was that the vanadium sites were reduced by NO or NH3 as electron donor; then, the superoxide ions appeared over vanadium. The experimental findings showed that the surface acidity, surface oxygen vacancies and the superoxide could be increased by fluorine doping, accordingly, the two-step process rate would be enhanced by F doping. It was the reason for F-doped catalyst had the higher catalytic activity than vanadia/titania. This two-step process could also be used to elucidate the inhibition mechanism of SO2 and H2O for the SCR reaction. ISSN : 1385-8947 En ligne : http://www.sciencedirect.com/science/article/pii/S1385894711010734 [article] NO (or NH3) + O2 adsorption on fluorine-doped vanadia/titania and its role in the mechanism of a two - step process characterized by EPR [texte imprimé] / Qin Zhong, Auteur ; Tianjiao Zhang, Auteur ; Yuntao Li, Auteur . - 2012 . - pp.390–395. Génie chimique Langues : Anglais (eng) in Chemical engineering journal > Vol. 174 N° 1 (Octobre 2011) . - pp.390–395 Mots-clés : Low-temperature  selective  catalytic  reduction  F-doping  Vanadia/titania  Superoxide  ions Résumé : This study aimed at elucidating a two-step process of the low-temperature selective catalytic reduction (SCR) reaction. The data were collected through studying the EPR signal of NO (or NH3) + O2 adsorption on fluorine-doped vanadia/titania and vanadia/titania catalysts used for SCR reaction, as well as the impact of SO2 and H2O added to the gas mixtures. The EPR experiments provided a new method to explain the SCR reaction, which were associated with NO (NH3) + O2 reacting systems and had been inferred step by step. In summary, the first step of the two-step process was that the vanadium sites were reduced by NO or NH3 as electron donor; then, the superoxide ions appeared over vanadium. The experimental findings showed that the surface acidity, surface oxygen vacancies and the superoxide could be increased by fluorine doping, accordingly, the two-step process rate would be enhanced by F doping. It was the reason for F-doped catalyst had the higher catalytic activity than vanadia/titania. This two-step process could also be used to elucidate the inhibition mechanism of SO2 and H2O for the SCR reaction. ISSN : 1385-8947 En ligne : http://www.sciencedirect.com/science/article/pii/S1385894711010734

Dimerization of fatty acid methyl ester using Brönsted - Lewis acidic ionic liquid as catalyst / Shiwei Liu in Chemical engineering journal, Vol. 174 N° 1 (Octobre 2011) 

Public ISBD [article]  in Chemical engineering journal > Vol. 174 N° 1 (Octobre 2011) . - pp.396–399 Titre : Dimerization of fatty acid methyl ester using Brönsted - Lewis acidic ionic liquid as catalyst Type de document : texte imprimé Auteurs : Shiwei Liu, Auteur ; Hongxia Zhou, Auteur ; Shitao Yu, Auteur Année de publication : 2012 Article en page(s) : pp.396–399 Note générale : Génie chimique Langues : Anglais (eng) Mots-clés : Brönsted  –  Lewis  acidic  ionic  liquid  Fatty  acid  methyl  esters  Dimerization  Catalysis Résumé : The dimerization of fatty acid methyl ester was investigated using Brönsted–Lewis acidic ionic liquids (ILs) as catalysts. It is found that IL (3-sulfonic acid)-propyl-triethylammonium chlorozincinate [HO3S–(CH2)3–NEt3]Cl–ZnCl2 (x = 0.64, x: molar fraction of ZnCl2, x = moles of ZnCl2/(moles of ZnCl2 + moles of ammonium salt) was of good catalytic performance. Under the optimum conditions m(biodiesel):m(IL) 15:1, biodiesel 15 g, reaction temperature 240 °C, and reaction time 5 h, the yield of product dimeric acid methyl ester was 96.8%. The reusability of IL was good and after it was used five times, the dimeric acid methyl ester yield was still more than 94%. Otherwise, a synergetic effect of Brönsted and Lewis acid sites enhanced the catalytic performance of the IL. ISSN : 1385-8947 En ligne : http://www.sciencedirect.com/science/article/pii/S1385894711010758 [article] Dimerization of fatty acid methyl ester using Brönsted - Lewis acidic ionic liquid as catalyst [texte imprimé] / Shiwei Liu, Auteur ; Hongxia Zhou, Auteur ; Shitao Yu, Auteur . - 2012 . - pp.396–399. Génie chimique Langues : Anglais (eng) in Chemical engineering journal > Vol. 174 N° 1 (Octobre 2011) . - pp.396–399 Mots-clés : Brönsted  –  Lewis  acidic  ionic  liquid  Fatty  acid  methyl  esters  Dimerization  Catalysis Résumé : The dimerization of fatty acid methyl ester was investigated using Brönsted–Lewis acidic ionic liquids (ILs) as catalysts. It is found that IL (3-sulfonic acid)-propyl-triethylammonium chlorozincinate [HO3S–(CH2)3–NEt3]Cl–ZnCl2 (x = 0.64, x: molar fraction of ZnCl2, x = moles of ZnCl2/(moles of ZnCl2 + moles of ammonium salt) was of good catalytic performance. Under the optimum conditions m(biodiesel):m(IL) 15:1, biodiesel 15 g, reaction temperature 240 °C, and reaction time 5 h, the yield of product dimeric acid methyl ester was 96.8%. The reusability of IL was good and after it was used five times, the dimeric acid methyl ester yield was still more than 94%. Otherwise, a synergetic effect of Brönsted and Lewis acid sites enhanced the catalytic performance of the IL. ISSN : 1385-8947 En ligne : http://www.sciencedirect.com/science/article/pii/S1385894711010758

Prominent enhancement of Mn or Co addition on the performance of Cu - Ce - O catalyst used for H2 production via dimethyl ether steam reforming / Xiaoyan Zhou in Chemical engineering journal, Vol. 174 N° 1 (Octobre 2011) 

Public ISBD [article]  in Chemical engineering journal > Vol. 174 N° 1 (Octobre 2011) . - pp. 400–407 Titre : Prominent enhancement of Mn or Co addition on the performance of Cu - Ce - O catalyst used for H2 production via dimethyl ether steam reforming Type de document : texte imprimé Auteurs : Xiaoyan Zhou, Auteur ; Ming Meng, Auteur ; Zhaosong Sun, Auteur Année de publication : 2012 Article en page(s) : pp. 400–407 Note générale : Génie chimique Langues : Anglais (eng) Mots-clés : Cu-Ce-O  catalyst  Promoter  Cobalt  Manganese  H2  production  Dimethyl  ether  steam  reforming Résumé : The Mn or Co promoted Cu-Ce-O catalysts were prepared by citric acid complexation, and used for the catalytic production of hydrogen via the route of dimethyl ether steam reforming (DME SR). Multiple techniques such as X-ray diffraction (XRD), X-ray absorption fine structure (XAFS), X-ray photoelectron spectra (XPS), temperature-programmed reduction by H2 (H2-TPR), CO-pulse chemisorption and thermal gravimetry/differential thermal analysis (TG/DTA) were employed for catalyst characterization. It is revealed by the results of XRD, XPS and XAFS that in the spent catalysts the copper species mainly exist as Cu0 and Cu+. The addition of Co or Mn could enhance both the dispersion and the reducibility of copper species, significantly increasing the DME conversion and H2 yield at the temperature of 400 °C or below. At higher temperature, the H2 yield over Cu-Ce-Co-O is almost the same as that for Cu-Ce-O, due to the side reactions of CH3OH decomposition and/or DME steam reforming to syngas. Addition of Mn to Cu-Ce-O can increase both DME conversion and H2 yield in the whole temperature region of 300–450 °C. Much higher CO2 selectivity is achieved over the Mn promoted catalyst. XPS and CO-pulse chemisorption results indicate that Cu-Ce-Mn-O catalyst contains more Cu+ species, which determines its novel catalytic performance including higher DME conversion and higher H2 yield. ISSN : 1385-8947 En ligne : http://www.sciencedirect.com/science/article/pii/S138589471101076X [article] Prominent enhancement of Mn or Co addition on the performance of Cu - Ce - O catalyst used for H2 production via dimethyl ether steam reforming [texte imprimé] / Xiaoyan Zhou, Auteur ; Ming Meng, Auteur ; Zhaosong Sun, Auteur . - 2012 . - pp. 400–407. Génie chimique Langues : Anglais (eng) in Chemical engineering journal > Vol. 174 N° 1 (Octobre 2011) . - pp. 400–407 Mots-clés : Cu-Ce-O  catalyst  Promoter  Cobalt  Manganese  H2  production  Dimethyl  ether  steam  reforming Résumé : The Mn or Co promoted Cu-Ce-O catalysts were prepared by citric acid complexation, and used for the catalytic production of hydrogen via the route of dimethyl ether steam reforming (DME SR). Multiple techniques such as X-ray diffraction (XRD), X-ray absorption fine structure (XAFS), X-ray photoelectron spectra (XPS), temperature-programmed reduction by H2 (H2-TPR), CO-pulse chemisorption and thermal gravimetry/differential thermal analysis (TG/DTA) were employed for catalyst characterization. It is revealed by the results of XRD, XPS and XAFS that in the spent catalysts the copper species mainly exist as Cu0 and Cu+. The addition of Co or Mn could enhance both the dispersion and the reducibility of copper species, significantly increasing the DME conversion and H2 yield at the temperature of 400 °C or below. At higher temperature, the H2 yield over Cu-Ce-Co-O is almost the same as that for Cu-Ce-O, due to the side reactions of CH3OH decomposition and/or DME steam reforming to syngas. Addition of Mn to Cu-Ce-O can increase both DME conversion and H2 yield in the whole temperature region of 300–450 °C. Much higher CO2 selectivity is achieved over the Mn promoted catalyst. XPS and CO-pulse chemisorption results indicate that Cu-Ce-Mn-O catalyst contains more Cu+ species, which determines its novel catalytic performance including higher DME conversion and higher H2 yield. ISSN : 1385-8947 En ligne : http://www.sciencedirect.com/science/article/pii/S138589471101076X

Interfacial synergistic effect of the Cu monomer or CuO dimer modified CeO2(1 1 1) catalyst for CO oxidation / Kenneth Wong in Chemical engineering journal, Vol. 174 N° 1 (Octobre 2011) 

Public ISBD [article]  in Chemical engineering journal > Vol. 174 N° 1 (Octobre 2011) . - pp.408–412 Titre : Interfacial synergistic effect of the Cu monomer or CuO dimer modified CeO2(1 1 1) catalyst for CO oxidation Type de document : texte imprimé Auteurs : Kenneth Wong, Auteur ; Zeng, Qinghua, Auteur ; Aibing Yu, Auteur Année de publication : 2012 Article en page(s) : pp.408–412 Note générale : Génie chimique Langues : Anglais (eng) Mots-clés : Interface  Synergistic  effect  CO  oxidation  Catalysis  Molecular  simulation Résumé : The synergistic effect at the interface of the bilayer Cu monomer or CuO dimer modified CeO2(1 1 1) catalyst for CO oxidation is investigated with density functional theory calculation. Important factors related to the synergistic effect such as interfacial ionicity, electron transfer, and charge partitioning of the Cu modifications are analyzed in detail for better understanding and control of this catalyst system. ISSN : 1385-8947 En ligne : http://www.sciencedirect.com/science/article/pii/S1385894711010783 [article] Interfacial synergistic effect of the Cu monomer or CuO dimer modified CeO2(1 1 1) catalyst for CO oxidation [texte imprimé] / Kenneth Wong, Auteur ; Zeng, Qinghua, Auteur ; Aibing Yu, Auteur . - 2012 . - pp.408–412. Génie chimique Langues : Anglais (eng) in Chemical engineering journal > Vol. 174 N° 1 (Octobre 2011) . - pp.408–412 Mots-clés : Interface  Synergistic  effect  CO  oxidation  Catalysis  Molecular  simulation Résumé : The synergistic effect at the interface of the bilayer Cu monomer or CuO dimer modified CeO2(1 1 1) catalyst for CO oxidation is investigated with density functional theory calculation. Important factors related to the synergistic effect such as interfacial ionicity, electron transfer, and charge partitioning of the Cu modifications are analyzed in detail for better understanding and control of this catalyst system. ISSN : 1385-8947 En ligne : http://www.sciencedirect.com/science/article/pii/S1385894711010783

Precipitation of calcium carbonate by carbon dioxide microbubbles / Jun-Hwan Bang in Chemical engineering journal, Vol. 174 N° 1 (Octobre 2011) 

Public ISBD [article]  in Chemical engineering journal > Vol. 174 N° 1 (Octobre 2011) . - pp. 413–420 Titre : Precipitation of calcium carbonate by carbon dioxide microbubbles Type de document : texte imprimé Auteurs : Jun-Hwan Bang, Auteur ; Young Nam Jang, Auteur ; Wonbaek Kim, Auteur Année de publication : 2012 Article en page(s) : pp. 413–420 Note générale : Génie chimique Langues : Anglais (eng) Mots-clés : Microbubble  Carbon  dioxide  Calcium  carbonate  Carbonation  route Résumé : The microbubble generator (MBG)—an apparatus in which tiny micron-sized gas bubbles are produced in the aqueous phase—has been widely used in water purification systems. In this study, the feasibility of utilizing the MBG to precipitate calcium carbonate along the carbonation route was examined. The effects of the calcium hydroxide concentration and the injection flow rate of carbon dioxide on the precipitation process were evaluated. Changes in pH, temperature of the suspension, and residual calcium ion concentration in the suspension were monitored to evaluate the proposed process. In addition, the process was compared with that based on a conventional bubble generator. This revealed a two-fold improvement in the acquisition time required for calcium carbonate precipitation as well as an increase in the conversion efficiency of carbon dioxide to carbonate minerals. The proposed process should be helpful for practical applications of a carbon sequestration method. ISSN : 1385-8947 En ligne : http://www.sciencedirect.com/science/article/pii/S1385894711010795 [article] Precipitation of calcium carbonate by carbon dioxide microbubbles [texte imprimé] / Jun-Hwan Bang, Auteur ; Young Nam Jang, Auteur ; Wonbaek Kim, Auteur . - 2012 . - pp. 413–420. Génie chimique Langues : Anglais (eng) in Chemical engineering journal > Vol. 174 N° 1 (Octobre 2011) . - pp. 413–420 Mots-clés : Microbubble  Carbon  dioxide  Calcium  carbonate  Carbonation  route Résumé : The microbubble generator (MBG)—an apparatus in which tiny micron-sized gas bubbles are produced in the aqueous phase—has been widely used in water purification systems. In this study, the feasibility of utilizing the MBG to precipitate calcium carbonate along the carbonation route was examined. The effects of the calcium hydroxide concentration and the injection flow rate of carbon dioxide on the precipitation process were evaluated. Changes in pH, temperature of the suspension, and residual calcium ion concentration in the suspension were monitored to evaluate the proposed process. In addition, the process was compared with that based on a conventional bubble generator. This revealed a two-fold improvement in the acquisition time required for calcium carbonate precipitation as well as an increase in the conversion efficiency of carbon dioxide to carbonate minerals. The proposed process should be helpful for practical applications of a carbon sequestration method. ISSN : 1385-8947 En ligne : http://www.sciencedirect.com/science/article/pii/S1385894711010795

Conductive composites of polyamide - 6 with polyaniline coated vegetal fiber / J. R. Araujo in Chemical engineering journal, Vol. 174 N° 1 (Octobre 2011) 

Public ISBD [article]  in Chemical engineering journal > Vol. 174 N° 1 (Octobre 2011) . - pp. 425–431 Titre : Conductive composites of polyamide - 6 with polyaniline coated vegetal fiber Type de document : texte imprimé Auteurs : J. R. Araujo, Auteur ; C. B. Adamo, Auteur ; Marco-A. De Paoli, Auteur Année de publication : 2012 Article en page(s) : pp. 425–431 Note générale : Génie chimique Langues : Anglais (eng) Mots-clés : Biofibers  Composites  Conducting  polymers  Extrusion  Polyamides  Reinforcement Résumé : Vegetal fibers, like curauá fibers, are used as reinforcement for thermoplastics in biocomposites, due to their low density and availability. Polyaniline can be deposited on the surface of fibers producing electrically conductive fibers. The conductivity of these PAni treated fibers suggest their use as antistatic agents. Composites of polyamide-6 with Pani-treated curaua fibers were prepared in a twin-screw extruder and specimens were obtained by transfer-molding. The electrical properties of the modified fibers and composites were measured and the mechanical properties were evaluated by tensile tests. The morphology of the composites, the fibrillation process and adhesion at the polymer/fiber interface were observed by scanning electron micrography. The ATR-FTIR showed that the most important bands of PAni were present in the modified fibers. The thermogravimetric results showed that the PAni-coated fibers present two distinct weight loss processes with a positive shift of the PAni degradation process, corresponding to a stabilization effect. The composite has a conductivity of 5 × 10−7 S cm−1, three orders of magnitude higher than pure polyamide-6, and in the range of antistatic materials. The composites with PAni-coated fibers show better mechanical performance than the polymer matrix, and SEM shows good adhesion at the polymer/fiber interface. ISSN : 1385-8947 En ligne : http://www.sciencedirect.com/science/article/pii/S1385894711010084 [article] Conductive composites of polyamide - 6 with polyaniline coated vegetal fiber [texte imprimé] / J. R. Araujo, Auteur ; C. B. Adamo, Auteur ; Marco-A. De Paoli, Auteur . - 2012 . - pp. 425–431. Génie chimique Langues : Anglais (eng) in Chemical engineering journal > Vol. 174 N° 1 (Octobre 2011) . - pp. 425–431 Mots-clés : Biofibers  Composites  Conducting  polymers  Extrusion  Polyamides  Reinforcement Résumé : Vegetal fibers, like curauá fibers, are used as reinforcement for thermoplastics in biocomposites, due to their low density and availability. Polyaniline can be deposited on the surface of fibers producing electrically conductive fibers. The conductivity of these PAni treated fibers suggest their use as antistatic agents. Composites of polyamide-6 with Pani-treated curaua fibers were prepared in a twin-screw extruder and specimens were obtained by transfer-molding. The electrical properties of the modified fibers and composites were measured and the mechanical properties were evaluated by tensile tests. The morphology of the composites, the fibrillation process and adhesion at the polymer/fiber interface were observed by scanning electron micrography. The ATR-FTIR showed that the most important bands of PAni were present in the modified fibers. The thermogravimetric results showed that the PAni-coated fibers present two distinct weight loss processes with a positive shift of the PAni degradation process, corresponding to a stabilization effect. The composite has a conductivity of 5 × 10−7 S cm−1, three orders of magnitude higher than pure polyamide-6, and in the range of antistatic materials. The composites with PAni-coated fibers show better mechanical performance than the polymer matrix, and SEM shows good adhesion at the polymer/fiber interface. ISSN : 1385-8947 En ligne : http://www.sciencedirect.com/science/article/pii/S1385894711010084

Sonochemical preparation of massive CrO2 nanowires / Shao-Min Zhou in Chemical engineering journal, Vol. 174 N° 1 (Octobre 2011) 

Public ISBD [article]  in Chemical engineering journal > Vol. 174 N° 1 (Octobre 2011) . - pp. 432–435 Titre : Sonochemical preparation of massive CrO2 nanowires Type de document : texte imprimé Auteurs : Shao-Min Zhou, Auteur ; Gong-Yu Zhu, Auteur ; Yong-Qiang Wang, Auteur Année de publication : 2012 Article en page(s) : pp. 432–435 Note générale : Génie chimique Langues : Anglais (eng) Mots-clés : Nanostructures  Ferromagnetism  Quantum  wires  Spin  polarized Résumé : One-dimensional (1D) nanostructures with precise controlled morphologies have not been easily accessible, usually degrading the device performance and therefore limiting applications to various advanced nanoscale magnetism. Generally bulk chromium dioxides are prepared by solid/liquid-phase reactions at elevated pressures or the chemical vapor deposition procedure whereas a liquid synthesis at non-pressure conditions, particularly for sonochemical one, has really been a challenge. Here we report on an ultrasound fabrication of large-scale CrO2 nanowires by using CrO2Cl2 and homemade Cr2O3 hollow nanospheres for the first time. The as-synthesized products were characterized by X-ray diffraction/photoelectron spectroscopy, scanning/transmission electron microscopy, high-resolution transmission electron microscopy, energy dispersive X-ray spectroscopy, selected area electron diffraction, and superconducting quantum interference devices magnetometer, respectively. The results show the controlled nanowires with diameter of 100–200 nm possess a single crystal tetragonal structure and exhibit a colossal coercive field (1678 Oe) at room-temperature, which could have potential applications in spin filtering, high density magnetic recording, and nanosensors. The proposed chemical reaction mechanism is suggested in detail and such a colossal coercive field is tentatively explained. ISSN : 1385-8947 En ligne : http://www.sciencedirect.com/science/article/pii/S1385894711010102 [article] Sonochemical preparation of massive CrO2 nanowires [texte imprimé] / Shao-Min Zhou, Auteur ; Gong-Yu Zhu, Auteur ; Yong-Qiang Wang, Auteur . - 2012 . - pp. 432–435. Génie chimique Langues : Anglais (eng) in Chemical engineering journal > Vol. 174 N° 1 (Octobre 2011) . - pp. 432–435 Mots-clés : Nanostructures  Ferromagnetism  Quantum  wires  Spin  polarized Résumé : One-dimensional (1D) nanostructures with precise controlled morphologies have not been easily accessible, usually degrading the device performance and therefore limiting applications to various advanced nanoscale magnetism. Generally bulk chromium dioxides are prepared by solid/liquid-phase reactions at elevated pressures or the chemical vapor deposition procedure whereas a liquid synthesis at non-pressure conditions, particularly for sonochemical one, has really been a challenge. Here we report on an ultrasound fabrication of large-scale CrO2 nanowires by using CrO2Cl2 and homemade Cr2O3 hollow nanospheres for the first time. The as-synthesized products were characterized by X-ray diffraction/photoelectron spectroscopy, scanning/transmission electron microscopy, high-resolution transmission electron microscopy, energy dispersive X-ray spectroscopy, selected area electron diffraction, and superconducting quantum interference devices magnetometer, respectively. The results show the controlled nanowires with diameter of 100–200 nm possess a single crystal tetragonal structure and exhibit a colossal coercive field (1678 Oe) at room-temperature, which could have potential applications in spin filtering, high density magnetic recording, and nanosensors. The proposed chemical reaction mechanism is suggested in detail and such a colossal coercive field is tentatively explained. ISSN : 1385-8947 En ligne : http://www.sciencedirect.com/science/article/pii/S1385894711010102

Preparation and characterization of mercapto functionalized sepiolite and their application for sorption of lead and cadmium / Xuefeng Liang in Chemical engineering journal, Vol. 174 N° 1 (Octobre 2011) 

Public ISBD [article]  in Chemical engineering journal > Vol. 174 N° 1 (Octobre 2011) . - pp. 436–444 Titre : Preparation and characterization of mercapto functionalized sepiolite and their application for sorption of lead and cadmium Type de document : texte imprimé Auteurs : Xuefeng Liang, Auteur ; Yingming Xu, Auteur ; Guohong Sun, Auteur Année de publication : 2012 Article en page(s) : pp. 436–444 Note générale : Génie chimique Langues : Anglais (eng) Mots-clés : Sepiolite  Mercapto  Functionalization  Characterization  Sorption Résumé : In order to improve the sorption performance of sepiolite for heavy metals, sepiolite was functionalized by nanotexturization in aqueous sepiolite gel and surface grafting in toluene with mercaptopropyltrimethoxysilane. The pristine sepiolite and mercapto functionalized samples were characterized through XRD, FT-IR, SEM, TEM, TG, surface area analysis, solid state 29Si CP/MAS NMR. The chemical bonding took place between the silanol group within sepiolite and the methoxy group of mercaptopropyltrimethoxysilane. The reaction in aqueous gel produced a continuous coating of individual fibers of sepiolite compared with part grafting on the external surface in toluene. After surface modification, the surface areas decreased due to the bulk size of the mercapto ligand, but the crystal structure did not change obviously, and the stretching of mercapto could be detected by FT-IR. The sorption of Pb(II) and Cd(II) on the samples were studied in batch experiments and it was found that the surface modification can obviously increase the sorption capacities for Pb(II) and Cd(II). The mercapto functionalized sepiolite could provide a potential remedy for heavy metal contamination in soils and water. ISSN : 1385-8947 En ligne : http://www.sciencedirect.com/science/article/pii/S1385894711010187 [article] Preparation and characterization of mercapto functionalized sepiolite and their application for sorption of lead and cadmium [texte imprimé] / Xuefeng Liang, Auteur ; Yingming Xu, Auteur ; Guohong Sun, Auteur . - 2012 . - pp. 436–444. Génie chimique Langues : Anglais (eng) in Chemical engineering journal > Vol. 174 N° 1 (Octobre 2011) . - pp. 436–444 Mots-clés : Sepiolite  Mercapto  Functionalization  Characterization  Sorption Résumé : In order to improve the sorption performance of sepiolite for heavy metals, sepiolite was functionalized by nanotexturization in aqueous sepiolite gel and surface grafting in toluene with mercaptopropyltrimethoxysilane. The pristine sepiolite and mercapto functionalized samples were characterized through XRD, FT-IR, SEM, TEM, TG, surface area analysis, solid state 29Si CP/MAS NMR. The chemical bonding took place between the silanol group within sepiolite and the methoxy group of mercaptopropyltrimethoxysilane. The reaction in aqueous gel produced a continuous coating of individual fibers of sepiolite compared with part grafting on the external surface in toluene. After surface modification, the surface areas decreased due to the bulk size of the mercapto ligand, but the crystal structure did not change obviously, and the stretching of mercapto could be detected by FT-IR. The sorption of Pb(II) and Cd(II) on the samples were studied in batch experiments and it was found that the surface modification can obviously increase the sorption capacities for Pb(II) and Cd(II). The mercapto functionalized sepiolite could provide a potential remedy for heavy metal contamination in soils and water. ISSN : 1385-8947 En ligne : http://www.sciencedirect.com/science/article/pii/S1385894711010187

Crystallization of anatase nanoparticles from amorphous precipitate by a continuous hydrothermal process / Kinga A. Malinger in Chemical engineering journal, Vol. 174 N° 1 (Octobre 2011) 

Public ISBD [article]  in Chemical engineering journal > Vol. 174 N° 1 (Octobre 2011) . - pp.445–451 Titre : Crystallization of anatase nanoparticles from amorphous precipitate by a continuous hydrothermal process Type de document : texte imprimé Auteurs : Kinga A. Malinger, Auteur ; Aude Maguer, Auteur ; Alain Thorel, Auteur Année de publication : 2012 Article en page(s) : pp.445–451 Note générale : Génie chimique Langues : Anglais (eng) Mots-clés : Continuous  hydrothermal  crystallization  Anatase  nanoparticles  Fast  synthesis  Continuous  synthes Résumé : Anatase nanoparticles with controlled size in the range 7–13 nm were synthesized by a continuous hydrothermal crystallization of amorphous TiO2 precipitate in a tubular reactor. The amorphous precursor was obtained from a double jet precipitation of TiCl4 with NaOH at pH 3. Hydrothermal crystallization was performed in a tubular reactor. Two main parameters were studied: the mean residence time of the slurry ranged from 10 to 30 min and transformation temperature from 120 to 220 °C. All samples have been characterized by Transmission Electron Microscopy, X-ray diffraction, and specific surface area measurement by N2 adsorption/desorption measurements. Well-crystallized anatase particles were obtained within few minutes at temperatures as low as 120 °C with a low polydispersity. Relationship between particle size and process parameters as temperature and residence time was determined. Due to the very slight variations in particle size vs process parameters, it is necessary to add up several techniques to give a reliable description of the samples as far as average aspect ratio, characteristic size and polydispersity are concerned. We propose to rely on TEM to get the average aspect ratio, then to rely on specific surface area to get the average particle size, and finally to check the consistency of these results with TEM and XRD peaks broadening. This self-consistent approach of particle characterization provides a correct and accurate description of the samples, and helps to optimize process parameters for photocatalytic applications, for instance. ISSN : 1385-8947 En ligne : http://www.sciencedirect.com/science/article/pii/S1385894711010230 [article] Crystallization of anatase nanoparticles from amorphous precipitate by a continuous hydrothermal process [texte imprimé] / Kinga A. Malinger, Auteur ; Aude Maguer, Auteur ; Alain Thorel, Auteur . - 2012 . - pp.445–451. Génie chimique Langues : Anglais (eng) in Chemical engineering journal > Vol. 174 N° 1 (Octobre 2011) . - pp.445–451 Mots-clés : Continuous  hydrothermal  crystallization  Anatase  nanoparticles  Fast  synthesis  Continuous  synthes Résumé : Anatase nanoparticles with controlled size in the range 7–13 nm were synthesized by a continuous hydrothermal crystallization of amorphous TiO2 precipitate in a tubular reactor. The amorphous precursor was obtained from a double jet precipitation of TiCl4 with NaOH at pH 3. Hydrothermal crystallization was performed in a tubular reactor. Two main parameters were studied: the mean residence time of the slurry ranged from 10 to 30 min and transformation temperature from 120 to 220 °C. All samples have been characterized by Transmission Electron Microscopy, X-ray diffraction, and specific surface area measurement by N2 adsorption/desorption measurements. Well-crystallized anatase particles were obtained within few minutes at temperatures as low as 120 °C with a low polydispersity. Relationship between particle size and process parameters as temperature and residence time was determined. Due to the very slight variations in particle size vs process parameters, it is necessary to add up several techniques to give a reliable description of the samples as far as average aspect ratio, characteristic size and polydispersity are concerned. We propose to rely on TEM to get the average aspect ratio, then to rely on specific surface area to get the average particle size, and finally to check the consistency of these results with TEM and XRD peaks broadening. This self-consistent approach of particle characterization provides a correct and accurate description of the samples, and helps to optimize process parameters for photocatalytic applications, for instance. ISSN : 1385-8947 En ligne : http://www.sciencedirect.com/science/article/pii/S1385894711010230

Exotemplating synthesis of nitrogen - doped carbon materials with hierarchically porous structure and their application for lysozyme adsorption / Gao-Song Shao in Chemical engineering journal, Vol. 174 N° 1 (Octobre 2011) 

Public ISBD [article]  in Chemical engineering journal > Vol. 174 N° 1 (Octobre 2011) . - pp. 452–460 Titre : Exotemplating synthesis of nitrogen - doped carbon materials with hierarchically porous structure and their application for lysozyme adsorption Type de document : texte imprimé Auteurs : Gao-Song Shao, Auteur ; Lei Liu, Auteur ; Tian-Yi Ma, Auteur Année de publication : 2012 Article en page(s) : pp. 452–460 Note générale : Génie chimique Langues : Anglais (eng) Mots-clés : Hierarchical  porosity  Exotemplating  Nitrogen-doping  Carbon  Vitamin  B6  Lysozyme  adsorption Résumé : Nitrogen-doped carbon materials with hierarchically porous structure were prepared by employing meso-/macroporous titania (MMT) as exotemplate with the use of Vitamin B6 (VB6) as both the carbon precursor and the nitrogen source for elemental doping. The synthesized materials were characterized by N2 sorption, scanning electron microscopy, transmission electron microscopy, Fourier transform infrared spectroscopy, and X-ray photoelectron spectroscopy. The obtained N-doped carbon materials have a multi-scaled porous hierarchy with pore sizes ranging from micropores, mesopores to macropores, and their morphology can be easily tuned through a simple adjustment of the weight ratio of VB6 to MMT. The different chemical state (pyridine-like N, quaternary N and oxidized N) and the content of nitrogen were analyzed by XPS. The prepared materials were used as the adsorbents for lysozyme. The effect of nitrogen doping on the lysozyme adsorption capability was investigated by comparison of the lysozyme adsorption behavior on the nitrogen-doped and nitrogen-free carbon materials with a similar pore structure. It was found that the nitrogen-containing carbon had higher adsorption capacity of lysozyme than that of the nitrogen-free carbons. En ligne : http://www.sciencedirect.com/science/article/pii/S1385894711010345 [article] Exotemplating synthesis of nitrogen - doped carbon materials with hierarchically porous structure and their application for lysozyme adsorption [texte imprimé] / Gao-Song Shao, Auteur ; Lei Liu, Auteur ; Tian-Yi Ma, Auteur . - 2012 . - pp. 452–460. Génie chimique Langues : Anglais (eng) in Chemical engineering journal > Vol. 174 N° 1 (Octobre 2011) . - pp. 452–460 Mots-clés : Hierarchical  porosity  Exotemplating  Nitrogen-doping  Carbon  Vitamin  B6  Lysozyme  adsorption Résumé : Nitrogen-doped carbon materials with hierarchically porous structure were prepared by employing meso-/macroporous titania (MMT) as exotemplate with the use of Vitamin B6 (VB6) as both the carbon precursor and the nitrogen source for elemental doping. The synthesized materials were characterized by N2 sorption, scanning electron microscopy, transmission electron microscopy, Fourier transform infrared spectroscopy, and X-ray photoelectron spectroscopy. The obtained N-doped carbon materials have a multi-scaled porous hierarchy with pore sizes ranging from micropores, mesopores to macropores, and their morphology can be easily tuned through a simple adjustment of the weight ratio of VB6 to MMT. The different chemical state (pyridine-like N, quaternary N and oxidized N) and the content of nitrogen were analyzed by XPS. The prepared materials were used as the adsorbents for lysozyme. The effect of nitrogen doping on the lysozyme adsorption capability was investigated by comparison of the lysozyme adsorption behavior on the nitrogen-doped and nitrogen-free carbon materials with a similar pore structure. It was found that the nitrogen-containing carbon had higher adsorption capacity of lysozyme than that of the nitrogen-free carbons. En ligne : http://www.sciencedirect.com/science/article/pii/S1385894711010345

Efficient synthesis route to quasi - aligned and high - aspect - ratio aluminum nitride micro - and nanostructures / Tae-Hyuk Lee in Chemical engineering journal, Vol. 174 N° 1 (Octobre 2011) 

Public ISBD [article]  in Chemical engineering journal > Vol. 174 N° 1 (Octobre 2011) . - pp.461–466 Titre : Efficient synthesis route to quasi - aligned and high - aspect - ratio aluminum nitride micro - and nanostructures Type de document : texte imprimé Auteurs : Tae-Hyuk Lee, Auteur ; Hayk H. Nersisyan, Auteur ; Ha-Guk Jeong, Auteur Année de publication : 2012 Article en page(s) : pp.461–466 Note générale : Génie chimique Langues : Anglais (eng) Mots-clés : Aluminum  nitride  Combustion  synthesis  Ceramic–metal  systems  Composites  ransmission  electron  microscopy Résumé : Quasi-aligned, high-aspect-ratio AlN micro- and nanostructures were synthesized under high nitrogen pressure by the exothermic reaction of an Al + 0.015 mol (C2F4)n mixture. Structurally uniform AlN micro- and nanofibers with hexagonal and cylindrical morphologies were obtained when the system temperature was maintained within the range of 1600–1700 °C. The fibers had aspect ratios as high as 2000, diameters in the range of ∼0.05–20 μm, and were ∼100–1000 μm in length. High-resolution transmission electron microscopic and selected area diffraction analyses indicated that the as-synthesized AlN micro- and nanostructures are perfectly single crystalline with preferential growth along the [0 0 1] direction. Branching was also observed in some of the micro-fibers, giving rise to randomized, two-dimensional comb textures. Based on the results obtained in the present study, a mechanism for the formation of AlN micro- and nanostructures under combustion conditions was proposed. ISSN : 1385-8947 En ligne : http://www.sciencedirect.com/science/article/pii/S1385894711011053 [article] Efficient synthesis route to quasi - aligned and high - aspect - ratio aluminum nitride micro - and nanostructures [texte imprimé] / Tae-Hyuk Lee, Auteur ; Hayk H. Nersisyan, Auteur ; Ha-Guk Jeong, Auteur . - 2012 . - pp.461–466. Génie chimique Langues : Anglais (eng) in Chemical engineering journal > Vol. 174 N° 1 (Octobre 2011) . - pp.461–466 Mots-clés : Aluminum  nitride  Combustion  synthesis  Ceramic–metal  systems  Composites  ransmission  electron  microscopy Résumé : Quasi-aligned, high-aspect-ratio AlN micro- and nanostructures were synthesized under high nitrogen pressure by the exothermic reaction of an Al + 0.015 mol (C2F4)n mixture. Structurally uniform AlN micro- and nanofibers with hexagonal and cylindrical morphologies were obtained when the system temperature was maintained within the range of 1600–1700 °C. The fibers had aspect ratios as high as 2000, diameters in the range of ∼0.05–20 μm, and were ∼100–1000 μm in length. High-resolution transmission electron microscopic and selected area diffraction analyses indicated that the as-synthesized AlN micro- and nanostructures are perfectly single crystalline with preferential growth along the [0 0 1] direction. Branching was also observed in some of the micro-fibers, giving rise to randomized, two-dimensional comb textures. Based on the results obtained in the present study, a mechanism for the formation of AlN micro- and nanostructures under combustion conditions was proposed. ISSN : 1385-8947 En ligne : http://www.sciencedirect.com/science/article/pii/S1385894711011053

Visible - light - induced heterostructured Zn – Al – In mixed metal oxide nanocomposite photocatalysts derived from a single precursor / Guoli Fan in Chemical engineering journal, Vol. 174 N° 1 (Octobre 2011) 

Public ISBD [article]  in Chemical engineering journal > Vol. 174 N° 1 (Octobre 2011) . - pp. 467–474 Titre : Visible - light - induced heterostructured Zn – Al – In mixed metal oxide nanocomposite photocatalysts derived from a single precursor Type de document : texte imprimé Auteurs : Guoli Fan, Auteur ; Wei Sun, Auteur ; Hui Wang, Auteur Année de publication : 2012 Article en page(s) : pp. 467–474 Note générale : Génie chimique Langues : Anglais (eng) Mots-clés : Indium  oxide  Zinc  oxide  Nanocomposite  Photocatalyst  Visible  light Résumé : The present work reported the synthesis of visible-light-induced heterostructured Zn–Al–In mixed metal oxide (ZnAlIn-MMO) nanocomposite photocatalysts derived from Zn–Al–In layered double hydroxide precursors. The structural and optical properties of the novel nanomaterials were characterized by powder X-ray diffraction (XRD), 27Al solid-state nuclear magnetic resonance (NMR), transmission electron microscopy (TEM), low temperature nitrogen adsorption–desorption experiments and UV–vis diffuse reflectance spectroscopy. The results reveal that the well-dispersed amorphous In2O3 domains can be intimately attached to ZnO nanocrystallites in the ZnAlIn-MMO nanocomposites, thus forming the heterostructure of mixed metal oxides, and that the band gaps of ZnAlIn-MMO nanomaterials are in the range of 2.50–2.60 eV, indicative of visible light absorption characteristic. Compared to single-phase In2O3 sample, ZnAlIn-MMO nanocomposites exhibited enhanced photocatalytic activity towards the degradation of methylene blue under visible light irradiation. Especially, ZnAlIn-MMO with the Zn/Al/In molar ratio of 6:1:1 had the highest photocatalytic activity, which was attributable to the efficient separation and transportation of photogenerated charge carriers originating from the novel heterostructure and large specific surface area of such nanocomposite. The present finding provides an approach to fabricate new types of visible-light-induced heteronanostructured photocatalysts. ISSN : 1385-8947 En ligne : http://www.sciencedirect.com/science/article/pii/S1385894711011120 [article] Visible - light - induced heterostructured Zn – Al – In mixed metal oxide nanocomposite photocatalysts derived from a single precursor [texte imprimé] / Guoli Fan, Auteur ; Wei Sun, Auteur ; Hui Wang, Auteur . - 2012 . - pp. 467–474. Génie chimique Langues : Anglais (eng) in Chemical engineering journal > Vol. 174 N° 1 (Octobre 2011) . - pp. 467–474 Mots-clés : Indium  oxide  Zinc  oxide  Nanocomposite  Photocatalyst  Visible  light Résumé : The present work reported the synthesis of visible-light-induced heterostructured Zn–Al–In mixed metal oxide (ZnAlIn-MMO) nanocomposite photocatalysts derived from Zn–Al–In layered double hydroxide precursors. The structural and optical properties of the novel nanomaterials were characterized by powder X-ray diffraction (XRD), 27Al solid-state nuclear magnetic resonance (NMR), transmission electron microscopy (TEM), low temperature nitrogen adsorption–desorption experiments and UV–vis diffuse reflectance spectroscopy. The results reveal that the well-dispersed amorphous In2O3 domains can be intimately attached to ZnO nanocrystallites in the ZnAlIn-MMO nanocomposites, thus forming the heterostructure of mixed metal oxides, and that the band gaps of ZnAlIn-MMO nanomaterials are in the range of 2.50–2.60 eV, indicative of visible light absorption characteristic. Compared to single-phase In2O3 sample, ZnAlIn-MMO nanocomposites exhibited enhanced photocatalytic activity towards the degradation of methylene blue under visible light irradiation. Especially, ZnAlIn-MMO with the Zn/Al/In molar ratio of 6:1:1 had the highest photocatalytic activity, which was attributable to the efficient separation and transportation of photogenerated charge carriers originating from the novel heterostructure and large specific surface area of such nanocomposite. The present finding provides an approach to fabricate new types of visible-light-induced heteronanostructured photocatalysts. ISSN : 1385-8947 En ligne : http://www.sciencedirect.com/science/article/pii/S1385894711011120

Enforcing mass conservation in DPM - CFD models of dense particulate flows / C.L. Wu in Chemical engineering journal, Vol. 174 N° 1 (Octobre 2011) 

Public ISBD [article]  in Chemical engineering journal > Vol. 174 N° 1 (Octobre 2011) . - pp.475–481 Titre : Enforcing mass conservation in DPM - CFD models of dense particulate flows Type de document : texte imprimé Auteurs : C.L. Wu, Auteur ; K. Nandakumar, Auteur ; A. S. Berrouk, Auteur Année de publication : 2012 Article en page(s) : pp.475–481 Note générale : Génie chimique Langues : Anglais (eng) Mots-clés : Mass  conversation  Discrete  particle/element  modeling  Computational  fluid  dynamics  Dense  particulate  flow Résumé : An improved coupling method is proposed to ensure mass conservation in a previously developed DPM-CFD model (C.L. Wu et al., Three-dimensional discrete particle model for gas–solid fluidized bed on unstructured mesh, Chemical Engineering Journal 152 (2009), 514–529). In enforcing the mass balance for the continuous phase in such algorithms using the single phase flow solvers, any heterogeneity in the particle concentration field (caused by clustering of particles) creates non-zero source terms. It is shown that if this is not handled properly, it can create large numerical errors (of up to 10%) and any oscillation in the flow field manifests itself in a similar error in the mass conservation. By using the conservative form of the equations in integral formulation, the coupling between the DPM and CFD models ensures mass conservation on the global scale in the entire domain, even in the presence of local heterogeneities in the flow field. The method also offers a consistent implementation of mass flow boundaries at the inlet. Numerical results show the superiority of the new coupling method over the previous one in conserving mass and handling transport processes in fluidized beds. ISSN : 1385-8947 En ligne : http://www.sciencedirect.com/science/article/pii/S138589471100979X [article] Enforcing mass conservation in DPM - CFD models of dense particulate flows [texte imprimé] / C.L. Wu, Auteur ; K. Nandakumar, Auteur ; A. S. Berrouk, Auteur . - 2012 . - pp.475–481. Génie chimique Langues : Anglais (eng) in Chemical engineering journal > Vol. 174 N° 1 (Octobre 2011) . - pp.475–481 Mots-clés : Mass  conversation  Discrete  particle/element  modeling  Computational  fluid  dynamics  Dense  particulate  flow Résumé : An improved coupling method is proposed to ensure mass conservation in a previously developed DPM-CFD model (C.L. Wu et al., Three-dimensional discrete particle model for gas–solid fluidized bed on unstructured mesh, Chemical Engineering Journal 152 (2009), 514–529). In enforcing the mass balance for the continuous phase in such algorithms using the single phase flow solvers, any heterogeneity in the particle concentration field (caused by clustering of particles) creates non-zero source terms. It is shown that if this is not handled properly, it can create large numerical errors (of up to 10%) and any oscillation in the flow field manifests itself in a similar error in the mass conservation. By using the conservative form of the equations in integral formulation, the coupling between the DPM and CFD models ensures mass conservation on the global scale in the entire domain, even in the presence of local heterogeneities in the flow field. The method also offers a consistent implementation of mass flow boundaries at the inlet. Numerical results show the superiority of the new coupling method over the previous one in conserving mass and handling transport processes in fluidized beds. ISSN : 1385-8947 En ligne : http://www.sciencedirect.com/science/article/pii/S138589471100979X

Fluorescent clays — Similar transfer with sensitive detection / Vitaly Gitis in Chemical engineering journal, Vol. 174 N° 1 (Octobre 2011) 

Public ISBD [article]  in Chemical engineering journal > Vol. 174 N° 1 (Octobre 2011) . - pp.482–488 Titre : Fluorescent clays — Similar transfer with sensitive detection Type de document : texte imprimé Auteurs : Vitaly Gitis, Auteur ; Christina Dlugy, Auteur ; Gennady Ziskind, Auteur Année de publication : 2012 Article en page(s) : pp.482–488 Note générale : Génie chimique Langues : Anglais (eng) Mots-clés : MMT  Rhodamine  6G  Subsoil  Residence  time  distribution  Turbidity Résumé : The significant probe dilution is one of the reasons to use soluble dyes and concentrated ion solutions for studies of colloid transport in subsoils and aquifers. We studied the clay transport in sand columns with Rhodamine 6G-intercalated montmorillonite (MMT). Our MMT-R exhibited transfer properties similar to the non-dyed clays but was detectable starting from 1 ppb by fluorescence and only from 0.5 ppm by turbidity. More contaminated soil adsorbed the MMT-R better than the pure one and therefore the reduction of influent turbidity may have the unintended effect of decreasing soil adsorption capacity. ISSN : 1385-8947 En ligne : http://www.sciencedirect.com/science/article/pii/S1385894711010217# [article] Fluorescent clays — Similar transfer with sensitive detection [texte imprimé] / Vitaly Gitis, Auteur ; Christina Dlugy, Auteur ; Gennady Ziskind, Auteur . - 2012 . - pp.482–488. Génie chimique Langues : Anglais (eng) in Chemical engineering journal > Vol. 174 N° 1 (Octobre 2011) . - pp.482–488 Mots-clés : MMT  Rhodamine  6G  Subsoil  Residence  time  distribution  Turbidity Résumé : The significant probe dilution is one of the reasons to use soluble dyes and concentrated ion solutions for studies of colloid transport in subsoils and aquifers. We studied the clay transport in sand columns with Rhodamine 6G-intercalated montmorillonite (MMT). Our MMT-R exhibited transfer properties similar to the non-dyed clays but was detectable starting from 1 ppb by fluorescence and only from 0.5 ppm by turbidity. More contaminated soil adsorbed the MMT-R better than the pure one and therefore the reduction of influent turbidity may have the unintended effect of decreasing soil adsorption capacity. ISSN : 1385-8947 En ligne : http://www.sciencedirect.com/science/article/pii/S1385894711010217#

Preparation and characterization of magnetic rectorite / iron oxide nanocomposites and its application for the removal of the dyes / Dongliang Wu in Chemical engineering journal, Vol. 174 N° 1 (Octobre 2011) 

Public ISBD [article]  in Chemical engineering journal > Vol. 174 N° 1 (Octobre 2011) . - pp. 489–494 Titre : Preparation and characterization of magnetic rectorite / iron oxide nanocomposites and its application for the removal of the dyes Type de document : texte imprimé Auteurs : Dongliang Wu, Auteur ; Pengwu Zheng, Auteur ; Peter R. Chang, Auteur Année de publication : 2012 Article en page(s) : pp. 489–494 Note générale : Génie chimique Langues : Anglais (eng) Mots-clés : Adsorption  Dye  Fe3O4  Rectorite Résumé : The superparamagnetic Fe3O4 nanoparticles were synthesized on the rectorite (REC) to prepare the adsorbent of magnetic REC (REC-Fe3O4), which was explored to adsorb three dyes, namely methylene blue (MB), neutral red (NR) and methyl orange (MO). Characterization of REC-Fe3O4 by Fourier transform infrared spectroscopy, transmission electron microscopy and X-ray diffraction showed that REC was attached with clusters of Fe3O4 nanoparticles. And the galleries in the REC were partially exfoliated when Fe3O4 were formed on the new surface of REC. There were still some galleries, which were not exfoliated in REC-Fe3O4. Magnetic properties revealed that REC-Fe3O4 was superparamagnetic with a saturation magnetization (19.14 emu/g). The adsorption behavior of REC and REC-Fe3O4 illustrated that it exhibited good adsorption for MB and NR, while the adsorption of MO was very little. And REC-Fe3O4 was easily separated from the aqueous solution in a magnetic field. ISSN : 1385-8947 En ligne : http://www.sciencedirect.com/science/article/pii/S1385894711010874 [article] Preparation and characterization of magnetic rectorite / iron oxide nanocomposites and its application for the removal of the dyes [texte imprimé] / Dongliang Wu, Auteur ; Pengwu Zheng, Auteur ; Peter R. Chang, Auteur . - 2012 . - pp. 489–494. Génie chimique Langues : Anglais (eng) in Chemical engineering journal > Vol. 174 N° 1 (Octobre 2011) . - pp. 489–494 Mots-clés : Adsorption  Dye  Fe3O4  Rectorite Résumé : The superparamagnetic Fe3O4 nanoparticles were synthesized on the rectorite (REC) to prepare the adsorbent of magnetic REC (REC-Fe3O4), which was explored to adsorb three dyes, namely methylene blue (MB), neutral red (NR) and methyl orange (MO). Characterization of REC-Fe3O4 by Fourier transform infrared spectroscopy, transmission electron microscopy and X-ray diffraction showed that REC was attached with clusters of Fe3O4 nanoparticles. And the galleries in the REC were partially exfoliated when Fe3O4 were formed on the new surface of REC. There were still some galleries, which were not exfoliated in REC-Fe3O4. Magnetic properties revealed that REC-Fe3O4 was superparamagnetic with a saturation magnetization (19.14 emu/g). The adsorption behavior of REC and REC-Fe3O4 illustrated that it exhibited good adsorption for MB and NR, while the adsorption of MO was very little. And REC-Fe3O4 was easily separated from the aqueous solution in a magnetic field. ISSN : 1385-8947 En ligne : http://www.sciencedirect.com/science/article/pii/S1385894711010874