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Vol. 51 N° 17 - Mai 2012 [texte imprimé] . - 2012 . - p. 5839-6274 : ill. ; 28 cm. Chemical engineering Langues : Anglais (eng)
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Ajouter le résultat dans votre panierMicroencapsulation of coenzyme Q10 in poly (ethylene glycol) and poly (lactic acid) with supercritical carbon dioxide / Maria del Socorro Vergara-Mendoza in Industrial & engineering chemistry research, Vol. 51 N° 17 (Mai 2012)
Titre : Microencapsulation of coenzyme Q10 in poly (ethylene glycol) and poly (lactic acid) with supercritical carbon dioxide Type de document : texte imprimé Auteurs : Maria del Socorro Vergara-Mendoza, Auteur ; Ciro-Humberto Ortiz-Estrada, Auteur ; Juana Gonzalez-Martinez, Auteur Année de publication : 2012 Article en page(s) : pp. 5840–5846 Note générale : Industrial chemistry Langues : Anglais (eng) Mots-clés : Polymeric microparticles Coenzyme Résumé : The rapid expansion of supercritical solutions (RESS) process was applied to produce polymeric microparticles loaded with coenzyme Q10 (coQ10). Mixtures of poly(lactic acid) (PLA)/(coQ10) and poly(ethylene glycol) (PEG)/(coQ10) containing a cosolvent were dissolved in supercritical CO2 and sprayed through a nozzle to atmospheric pressure. The effect of process parameters such as encapsulating material/coQ10 ratio and cosolvent on the properties of the microcapsules were investigated. The characterization of microcapsules was carried out through Scanning Electronic Microscopy (SEM), Infrared Spectrophotometry (IR), Differential Scanning Calorimetry (DSC), and solubility kinetics. More important effect of the ratio encapsulating material/coQ10, compared with the effect of type of cosolvent, on studied properties was found. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie2014839
in Industrial & engineering chemistry research > Vol. 51 N° 17 (Mai 2012) . - pp. 5840–5846[article] Microencapsulation of coenzyme Q10 in poly (ethylene glycol) and poly (lactic acid) with supercritical carbon dioxide [texte imprimé] / Maria del Socorro Vergara-Mendoza, Auteur ; Ciro-Humberto Ortiz-Estrada, Auteur ; Juana Gonzalez-Martinez, Auteur . - 2012 . - pp. 5840–5846.
Industrial chemistry
Langues : Anglais (eng)
in Industrial & engineering chemistry research > Vol. 51 N° 17 (Mai 2012) . - pp. 5840–5846
Mots-clés : Polymeric microparticles Coenzyme Résumé : The rapid expansion of supercritical solutions (RESS) process was applied to produce polymeric microparticles loaded with coenzyme Q10 (coQ10). Mixtures of poly(lactic acid) (PLA)/(coQ10) and poly(ethylene glycol) (PEG)/(coQ10) containing a cosolvent were dissolved in supercritical CO2 and sprayed through a nozzle to atmospheric pressure. The effect of process parameters such as encapsulating material/coQ10 ratio and cosolvent on the properties of the microcapsules were investigated. The characterization of microcapsules was carried out through Scanning Electronic Microscopy (SEM), Infrared Spectrophotometry (IR), Differential Scanning Calorimetry (DSC), and solubility kinetics. More important effect of the ratio encapsulating material/coQ10, compared with the effect of type of cosolvent, on studied properties was found. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie2014839 Exemplaires
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Titre : Dehydration of bioethanol by hybrid process liquid – liquid extraction/extractive distillation Type de document : texte imprimé Auteurs : Adriana Avilés Martinez, Auteur ; Jaime Saucedo-Luna, Auteur ; Juan Gabriel Segovia-Hernandez, Auteur Année de publication : 2012 Article en page(s) : pp. 5847–5855 Note générale : Industrial chemistry Langues : Anglais (eng) Mots-clés : Bioethanol Biofuels Distillation Résumé : Bioethanol is among the most promising of biofuels because it has an energy content similar to gasoline while generating lower pollutant emissions than gasoline. But, in order to be used as an automotive fuel mixed with gasoline, ethanol must have less than 0.5 wt % of water. To achieve required ethanol purity, in light of the fact that the ethanol–water mixture forms an azeotrope, unconventional separation techniques such as extractive distillation or azeotropic distillation are necessary. However, the purification of ethanol using conventional distillation followed by extractive distillation has the disadvantage of high cost of services. Thus, this study proposes alternative hybrid systems using liquid–liquid extraction and extractive distillation. The use of n-dodecane as entrainer for liquid–liquid extraction and glycerol as entrainer for extractive distillation has been considered. The proposed systems are analyzed and a comparison is done on their performance in terms of energy and total annual cost. It has been found that the hybrid scheme presents both lower total energy consumption and lower total annual cost as compared to the traditional purification scheme with conventional distillation and extractive distillation. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie200932g
in Industrial & engineering chemistry research > Vol. 51 N° 17 (Mai 2012) . - pp. 5847–5855[article] Dehydration of bioethanol by hybrid process liquid – liquid extraction/extractive distillation [texte imprimé] / Adriana Avilés Martinez, Auteur ; Jaime Saucedo-Luna, Auteur ; Juan Gabriel Segovia-Hernandez, Auteur . - 2012 . - pp. 5847–5855.
Industrial chemistry
Langues : Anglais (eng)
in Industrial & engineering chemistry research > Vol. 51 N° 17 (Mai 2012) . - pp. 5847–5855
Mots-clés : Bioethanol Biofuels Distillation Résumé : Bioethanol is among the most promising of biofuels because it has an energy content similar to gasoline while generating lower pollutant emissions than gasoline. But, in order to be used as an automotive fuel mixed with gasoline, ethanol must have less than 0.5 wt % of water. To achieve required ethanol purity, in light of the fact that the ethanol–water mixture forms an azeotrope, unconventional separation techniques such as extractive distillation or azeotropic distillation are necessary. However, the purification of ethanol using conventional distillation followed by extractive distillation has the disadvantage of high cost of services. Thus, this study proposes alternative hybrid systems using liquid–liquid extraction and extractive distillation. The use of n-dodecane as entrainer for liquid–liquid extraction and glycerol as entrainer for extractive distillation has been considered. The proposed systems are analyzed and a comparison is done on their performance in terms of energy and total annual cost. It has been found that the hybrid scheme presents both lower total energy consumption and lower total annual cost as compared to the traditional purification scheme with conventional distillation and extractive distillation. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie200932g Exemplaires
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Titre : Optimization and controllability analysis of thermally coupled reactive distillation arrangements with minimum use of reboilers Type de document : texte imprimé Auteurs : Maria Vazquez-Ojeda, Auteur ; Juan Gabriel Segovia-Hernandez, Auteur ; Salvador Hernandez, Auteur Année de publication : 2012 Article en page(s) : pp. 5856–5865 Note générale : Industrial chemistry Langues : Anglais (eng) Mots-clés : Optimization Distillation systems Résumé : The optimal design of reactive complex distillation systems is a highly nonlinear and multivariable problem, and the objective function used as optimization criterion is generally nonconvex with several local optimums and subject to several constraints. The esterification of lauric acid and methanol is explored using thermally coupled distillation sequences with side columns and with a minimum number of reboilers. The product of the esterification can be used as biodiesel. This is a major step forward since thermally coupled reactive distillation sequences with side columns and with a minimum number of reboilers offer significant benefits, such as the following: reductions on both capital investment and operating costs due to the absence of the reboilers and higher conversion and selectivity since products are removed as they are produced as well as no occurrence of thermal degradation of the products due to a lower temperature profile in the column. In this work, we have studied the design of reactive distillation with thermal coupling with a minimum number of reboilers, using differential evolution with restrictions coupled to AspenONE Aspen Plus. Also, we have analyzed the control properties of the reactive distillation schemes studied, and the results indicate that the energy requirements and the total annual cost of the complex distillation sequences with a minimum number of reboilers are reduced significantly in comparison with the conventional reactive distillation process and can be also achieved without significant control problems. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie200929t
in Industrial & engineering chemistry research > Vol. 51 N° 17 (Mai 2012) . - pp. 5856–5865[article] Optimization and controllability analysis of thermally coupled reactive distillation arrangements with minimum use of reboilers [texte imprimé] / Maria Vazquez-Ojeda, Auteur ; Juan Gabriel Segovia-Hernandez, Auteur ; Salvador Hernandez, Auteur . - 2012 . - pp. 5856–5865.
Industrial chemistry
Langues : Anglais (eng)
in Industrial & engineering chemistry research > Vol. 51 N° 17 (Mai 2012) . - pp. 5856–5865
Mots-clés : Optimization Distillation systems Résumé : The optimal design of reactive complex distillation systems is a highly nonlinear and multivariable problem, and the objective function used as optimization criterion is generally nonconvex with several local optimums and subject to several constraints. The esterification of lauric acid and methanol is explored using thermally coupled distillation sequences with side columns and with a minimum number of reboilers. The product of the esterification can be used as biodiesel. This is a major step forward since thermally coupled reactive distillation sequences with side columns and with a minimum number of reboilers offer significant benefits, such as the following: reductions on both capital investment and operating costs due to the absence of the reboilers and higher conversion and selectivity since products are removed as they are produced as well as no occurrence of thermal degradation of the products due to a lower temperature profile in the column. In this work, we have studied the design of reactive distillation with thermal coupling with a minimum number of reboilers, using differential evolution with restrictions coupled to AspenONE Aspen Plus. Also, we have analyzed the control properties of the reactive distillation schemes studied, and the results indicate that the energy requirements and the total annual cost of the complex distillation sequences with a minimum number of reboilers are reduced significantly in comparison with the conventional reactive distillation process and can be also achieved without significant control problems. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie200929t Exemplaires
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Titre : Simultaneous optimal design of an extractive column and ionic liquid for the separation of bioethanol – water mixtures Type de document : texte imprimé Auteurs : Darinel Valencia-Marquez, Auteur ; Antonio Flores-Tlacuahuac, Auteur ; Ruben Vasquez-Medrano, Auteur Année de publication : 2012 Article en page(s) : pp. 5866–5880 Note générale : Industrial chemistry Langues : Anglais (eng) Mots-clés : Optimal design Bioethanol Résumé : Recently renewed interest in the optimal design of sustainable processing systems has emerged as consequence of pollution issues and global climate changes. The replacement of hazardous industrial solvents widely used for azeotropic separations is clearly a challenging research area for new products design. However, as important as product design is, the design of the optimal processing configuration where the azeotropic separation will take place is also a key issue. As a matter of fact, the strong interaction between product and process design indicates that better optimal processing conditions can be attained by solving both problems simultaneously rather than sequentially. In the present work, we take advantage of this natural interaction for the optimal simultaneous design of both ionic liquids and an extractive distillation column for the high purity separation of the ethanol/water azeotropic mixture for deploying ethanol as a biofuel. The problem is formulated as a steady-state disjunctive mixed-integer nonlinear programming (MINLP) problem. The results indicate that new green solvents constitute a good replacement for hazardous solvents. Because ionic liquids are expensive solvents, it is worth it to explore the deployment of advanced optimization tools for profit maximization of sustainable processing systems. Through the use of the proposed MINLP formulation, improved ethanol/water separation configurations deploying ionic liquids were attained. Because ethanol features high purity, it can be used for biofuel applications. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie201726r
in Industrial & engineering chemistry research > Vol. 51 N° 17 (Mai 2012) . - pp. 5866–5880[article] Simultaneous optimal design of an extractive column and ionic liquid for the separation of bioethanol – water mixtures [texte imprimé] / Darinel Valencia-Marquez, Auteur ; Antonio Flores-Tlacuahuac, Auteur ; Ruben Vasquez-Medrano, Auteur . - 2012 . - pp. 5866–5880.
Industrial chemistry
Langues : Anglais (eng)
in Industrial & engineering chemistry research > Vol. 51 N° 17 (Mai 2012) . - pp. 5866–5880
Mots-clés : Optimal design Bioethanol Résumé : Recently renewed interest in the optimal design of sustainable processing systems has emerged as consequence of pollution issues and global climate changes. The replacement of hazardous industrial solvents widely used for azeotropic separations is clearly a challenging research area for new products design. However, as important as product design is, the design of the optimal processing configuration where the azeotropic separation will take place is also a key issue. As a matter of fact, the strong interaction between product and process design indicates that better optimal processing conditions can be attained by solving both problems simultaneously rather than sequentially. In the present work, we take advantage of this natural interaction for the optimal simultaneous design of both ionic liquids and an extractive distillation column for the high purity separation of the ethanol/water azeotropic mixture for deploying ethanol as a biofuel. The problem is formulated as a steady-state disjunctive mixed-integer nonlinear programming (MINLP) problem. The results indicate that new green solvents constitute a good replacement for hazardous solvents. Because ionic liquids are expensive solvents, it is worth it to explore the deployment of advanced optimization tools for profit maximization of sustainable processing systems. Through the use of the proposed MINLP formulation, improved ethanol/water separation configurations deploying ionic liquids were attained. Because ethanol features high purity, it can be used for biofuel applications. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie201726r Exemplaires
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Titre : A multiobjective optimization approach for the simultaneous single line scheduling and control of CSTRs Type de document : texte imprimé Auteurs : Miguel Angel Gutiérrez-Limon, Auteur ; Antonio Flores-Tlacuahuac, Auteur ; Ignacio E. Grossmann, Auteur Année de publication : 2012 Article en page(s) : pp. 5881–5890 Note générale : Industrial chemistry Langues : Anglais (eng) Mots-clés : Optimization Process dynamic Résumé : A new multiobjective optimization formulation dealing with simultaneous scheduling and control issues in single line processing systems is proposed. Objective functions featuring economic profit and dynamic performance are considered because normally they are in conflict. Because integer, continuous variables and process dynamic behavior are involved, the bicriterion optimization problem is cast in terms of a mixed-integer dynamic optimization (MIDO) problem. The Pareto front of each problem is computed using the ε-constraint method for handling multiobjective problems. The results indicate that improved optimal solutions can be obtained by using multiobjective optimization techniques instead of just simple merging of all the target objective functions into a single objective. The proposed multiobjective approach for handling scheduling and control problems is illustrated using three CSTR examples of varying nonlinear behavior. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie201740s
in Industrial & engineering chemistry research > Vol. 51 N° 17 (Mai 2012) . - pp. 5881–5890[article] A multiobjective optimization approach for the simultaneous single line scheduling and control of CSTRs [texte imprimé] / Miguel Angel Gutiérrez-Limon, Auteur ; Antonio Flores-Tlacuahuac, Auteur ; Ignacio E. Grossmann, Auteur . - 2012 . - pp. 5881–5890.
Industrial chemistry
Langues : Anglais (eng)
in Industrial & engineering chemistry research > Vol. 51 N° 17 (Mai 2012) . - pp. 5881–5890
Mots-clés : Optimization Process dynamic Résumé : A new multiobjective optimization formulation dealing with simultaneous scheduling and control issues in single line processing systems is proposed. Objective functions featuring economic profit and dynamic performance are considered because normally they are in conflict. Because integer, continuous variables and process dynamic behavior are involved, the bicriterion optimization problem is cast in terms of a mixed-integer dynamic optimization (MIDO) problem. The Pareto front of each problem is computed using the ε-constraint method for handling multiobjective problems. The results indicate that improved optimal solutions can be obtained by using multiobjective optimization techniques instead of just simple merging of all the target objective functions into a single objective. The proposed multiobjective approach for handling scheduling and control problems is illustrated using three CSTR examples of varying nonlinear behavior. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie201740s Exemplaires
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Titre : Multiobjective nonlinear model predictive control of a class of chemical reactors Type de document : texte imprimé Auteurs : Antonio Flores-Tlacuahuac, Auteur ; Pilar Morales, Auteur ; Martin Rivera-Toledo, Auteur Année de publication : 2012 Article en page(s) : pp. 5891–5899 Note générale : Industrial chemistry Langues : Anglais (eng) Mots-clés : Chemical reactors Optimization Résumé : Many problems in science and engineering can be posed as multiobjective optimization problems where several objectives must be met simultaneously. Commonly such multiobjective optimization problems are reduced to a single optimization problem by merging all the involved objective functions by using rather subjective weighting functions. This solution procedure can produce suboptimal solutions, and it is not a systematic method since the choice of the weighting functions is up to the designer. Process control is one of the engineering fields where multiobjective optimization control problems frequently emerge because such problems normally involve conflicting objective functions such as economical profit and environmental concerns. Because the optimal value of the conflicting objective functions cannot be simultaneously achieved one has to compute a trade-off solution that best suits, in a given sense, all the objective functions. Moreover, additional requirements, beyond upset rejection and set-point tracking, such as the determination of optimal operating conditions should also be handled by dynamic real time optimal control approaches. In this work we propose a novel multiobjective optimization and control approach able to get target points while simultaneously computing optimal operating conditions. The proposed approach can be applied to nonlinear dynamic systems and does not require the specification of arbitrary weighting functions to handle conflicting multiobjective optimization problems. Several case studies using chemical reactors of varying nonlinear behavior are deployed to illustrate the practical application of the proposed dynamic real time optimization approach. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie201742e
in Industrial & engineering chemistry research > Vol. 51 N° 17 (Mai 2012) . - pp. 5891–5899[article] Multiobjective nonlinear model predictive control of a class of chemical reactors [texte imprimé] / Antonio Flores-Tlacuahuac, Auteur ; Pilar Morales, Auteur ; Martin Rivera-Toledo, Auteur . - 2012 . - pp. 5891–5899.
Industrial chemistry
Langues : Anglais (eng)
in Industrial & engineering chemistry research > Vol. 51 N° 17 (Mai 2012) . - pp. 5891–5899
Mots-clés : Chemical reactors Optimization Résumé : Many problems in science and engineering can be posed as multiobjective optimization problems where several objectives must be met simultaneously. Commonly such multiobjective optimization problems are reduced to a single optimization problem by merging all the involved objective functions by using rather subjective weighting functions. This solution procedure can produce suboptimal solutions, and it is not a systematic method since the choice of the weighting functions is up to the designer. Process control is one of the engineering fields where multiobjective optimization control problems frequently emerge because such problems normally involve conflicting objective functions such as economical profit and environmental concerns. Because the optimal value of the conflicting objective functions cannot be simultaneously achieved one has to compute a trade-off solution that best suits, in a given sense, all the objective functions. Moreover, additional requirements, beyond upset rejection and set-point tracking, such as the determination of optimal operating conditions should also be handled by dynamic real time optimal control approaches. In this work we propose a novel multiobjective optimization and control approach able to get target points while simultaneously computing optimal operating conditions. The proposed approach can be applied to nonlinear dynamic systems and does not require the specification of arbitrary weighting functions to handle conflicting multiobjective optimization problems. Several case studies using chemical reactors of varying nonlinear behavior are deployed to illustrate the practical application of the proposed dynamic real time optimization approach. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie201742e Exemplaires
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Titre : Seawater desalination using modified ceramic membranes Type de document : texte imprimé Auteurs : V. Perez-Moreno, Auteur ; C. B. Bonilla-Suarez, Auteur ; M. Fortanell-Trejo, Auteur Année de publication : 2012 Article en page(s) : pp. 5900–5904 Note générale : Industrial chemistry Langues : Anglais (eng) Mots-clés : Ceramic membranes Résumé : Nanofiltration has many applications such as pretreatment and partial demineralization in seawater desalination processes. This paper studies the performance of commercial ceramic membranes, modified by depositing either platinum or silver, to reject salts of seawater. The membrane used is multilayer structured with a titania layer (5 kD MWCO) manufactured by TAMI Industries (Nyons, France) and anionic impregnation was used to depose platinum or silver onto the membrane. The effect of salts rejection of membranes was investigated using seawater from the Mexican Pacific coast. The tests were carried out at pressure of 6 bar and the experimental results showed that modified membranes could achieve a salt rejection close to 30% in total dissolved solids (TDS) whereas the rejection in nonmodified membranes was less than 5%. Anion and cation rejection was also determined, with higher values obtained for cation removal. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie2009313
in Industrial & engineering chemistry research > Vol. 51 N° 17 (Mai 2012) . - pp. 5900–5904[article] Seawater desalination using modified ceramic membranes [texte imprimé] / V. Perez-Moreno, Auteur ; C. B. Bonilla-Suarez, Auteur ; M. Fortanell-Trejo, Auteur . - 2012 . - pp. 5900–5904.
Industrial chemistry
Langues : Anglais (eng)
in Industrial & engineering chemistry research > Vol. 51 N° 17 (Mai 2012) . - pp. 5900–5904
Mots-clés : Ceramic membranes Résumé : Nanofiltration has many applications such as pretreatment and partial demineralization in seawater desalination processes. This paper studies the performance of commercial ceramic membranes, modified by depositing either platinum or silver, to reject salts of seawater. The membrane used is multilayer structured with a titania layer (5 kD MWCO) manufactured by TAMI Industries (Nyons, France) and anionic impregnation was used to depose platinum or silver onto the membrane. The effect of salts rejection of membranes was investigated using seawater from the Mexican Pacific coast. The tests were carried out at pressure of 6 bar and the experimental results showed that modified membranes could achieve a salt rejection close to 30% in total dissolved solids (TDS) whereas the rejection in nonmodified membranes was less than 5%. Anion and cation rejection was also determined, with higher values obtained for cation removal. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie2009313 Exemplaires
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Titre : An effective electrochemical Cr(VI) removal contained in electroplating industry wastewater and the chemical characterization of the sludge produced Type de document : texte imprimé Auteurs : Sarai Velazquez-Pena, Auteur ; Carlos Barrera-Díaz, Auteur ; Ivonne Linares-Hernandez, Auteur Année de publication : 2012 Article en page(s) : pp. 5905–5910 Note générale : Industrial chemistry Langues : Anglais (eng) Mots-clés : Electrochemical Electroplating wastewater Résumé : The goal of this work is to optimize the electrochemical reduction of hexavalent chromium in electroplating wastewater. The pH, electrolyte composition and concentration, and cathode metal were varied and the effect on reduction rate measured. Although all electrochemical systems studied reduced all Cr(VI) in the solutions, there were clear trends in the speed of the reactions. Because the reaction at pH 2 was faster than that at pH 4, acidity is favored. Higher electrolyte concentrations produced faster rates. Copper cathodes were faster than iron ones. Using the optimized conditions of pH 2 and a copper cathode, along with the high electrolyte concentration already present, actual electroplating wastewater was treated. The rate of Cr(VI) reduction was measured as a function of treatment time and was found to be even higher than that of the synthetic solutions. The 180 mg/L of Cr(VI) in the wastewater was completely reduced in about 15 min under optimal conditions. The sludge generated in the process was analyzed for morphology and elemental composition to provide insight into the mechanism of the reduction. The model electrochemical cell is as effective at reducing hexavalent chromium in actual electroplating wastewater as it is on synthetic solutions, so it can be effectively scaled up to industrial applications. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie200968s
in Industrial & engineering chemistry research > Vol. 51 N° 17 (Mai 2012) . - pp. 5905–5910[article] An effective electrochemical Cr(VI) removal contained in electroplating industry wastewater and the chemical characterization of the sludge produced [texte imprimé] / Sarai Velazquez-Pena, Auteur ; Carlos Barrera-Díaz, Auteur ; Ivonne Linares-Hernandez, Auteur . - 2012 . - pp. 5905–5910.
Industrial chemistry
Langues : Anglais (eng)
in Industrial & engineering chemistry research > Vol. 51 N° 17 (Mai 2012) . - pp. 5905–5910
Mots-clés : Electrochemical Electroplating wastewater Résumé : The goal of this work is to optimize the electrochemical reduction of hexavalent chromium in electroplating wastewater. The pH, electrolyte composition and concentration, and cathode metal were varied and the effect on reduction rate measured. Although all electrochemical systems studied reduced all Cr(VI) in the solutions, there were clear trends in the speed of the reactions. Because the reaction at pH 2 was faster than that at pH 4, acidity is favored. Higher electrolyte concentrations produced faster rates. Copper cathodes were faster than iron ones. Using the optimized conditions of pH 2 and a copper cathode, along with the high electrolyte concentration already present, actual electroplating wastewater was treated. The rate of Cr(VI) reduction was measured as a function of treatment time and was found to be even higher than that of the synthetic solutions. The 180 mg/L of Cr(VI) in the wastewater was completely reduced in about 15 min under optimal conditions. The sludge generated in the process was analyzed for morphology and elemental composition to provide insight into the mechanism of the reduction. The model electrochemical cell is as effective at reducing hexavalent chromium in actual electroplating wastewater as it is on synthetic solutions, so it can be effectively scaled up to industrial applications. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie200968s Exemplaires
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Titre : Multiobjective optimization for synthesizing compressor - aided distillation sequences with heat integration Type de document : texte imprimé Auteurs : J. Rafael Alcantara-Avila, Auteur ; Manabu Kano, Auteur ; Shinji Hasebe, Auteur Année de publication : 2012 Article en page(s) : pp. 5911–5921 Note générale : Industrial chemistry Langues : Anglais (eng) Mots-clés : Optimization Distillation Heat integration Résumé : Various column structures, configurations, and energy conservation methods have been proposed to reduce the cost and energy consumption in distillation sequences, such as thermally coupling or heat integration. In this work, a synthesis method of optimal separation sequences including thermally coupled columns is proposed. In the proposed method, vapor recompression of the flow to the condenser and pressure change within thermally coupled columns are taken into account to increase the possibility of heat integration. Furthermore, the energy requirement (ER) was adopted as the objective function as well as the total annual cost (TAC). By solving the multiobjective optimization problem, the relationship between the required annual cost and the amount of energy can be explicitly evaluated, i.e., the necessary cost increase per unit of energy input to the sequence can easily be assessed. A superstructure approach was adopted to enumerate all the candidate distillation sequences which consisted of conventional and thermally coupled columns. Rigorous simulations of each column were effectively used to assign reliable data to the optimization stage. Then, the process synthesis problem was formulated as a mixed integer linear programming (MILP) problem whose objective is to minimize TAC and ER. For two case study problems, Pareto-optimal solutions have been derived. The results of two case studies indicated that nonconventional sequences became the optimal for both cases. Vapor recompression was effective for minimizing the energy requirement. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie2017527
in Industrial & engineering chemistry research > Vol. 51 N° 17 (Mai 2012) . - pp. 5911–5921[article] Multiobjective optimization for synthesizing compressor - aided distillation sequences with heat integration [texte imprimé] / J. Rafael Alcantara-Avila, Auteur ; Manabu Kano, Auteur ; Shinji Hasebe, Auteur . - 2012 . - pp. 5911–5921.
Industrial chemistry
Langues : Anglais (eng)
in Industrial & engineering chemistry research > Vol. 51 N° 17 (Mai 2012) . - pp. 5911–5921
Mots-clés : Optimization Distillation Heat integration Résumé : Various column structures, configurations, and energy conservation methods have been proposed to reduce the cost and energy consumption in distillation sequences, such as thermally coupling or heat integration. In this work, a synthesis method of optimal separation sequences including thermally coupled columns is proposed. In the proposed method, vapor recompression of the flow to the condenser and pressure change within thermally coupled columns are taken into account to increase the possibility of heat integration. Furthermore, the energy requirement (ER) was adopted as the objective function as well as the total annual cost (TAC). By solving the multiobjective optimization problem, the relationship between the required annual cost and the amount of energy can be explicitly evaluated, i.e., the necessary cost increase per unit of energy input to the sequence can easily be assessed. A superstructure approach was adopted to enumerate all the candidate distillation sequences which consisted of conventional and thermally coupled columns. Rigorous simulations of each column were effectively used to assign reliable data to the optimization stage. Then, the process synthesis problem was formulated as a mixed integer linear programming (MILP) problem whose objective is to minimize TAC and ER. For two case study problems, Pareto-optimal solutions have been derived. The results of two case studies indicated that nonconventional sequences became the optimal for both cases. Vapor recompression was effective for minimizing the energy requirement. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie2017527 Exemplaires
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Titre : A mathematical programming approach to pollution trading Type de document : texte imprimé Auteurs : Francisco Lopez-Villarreal, Auteur ; Vicente Rico-Ramirez, Auteur ; Guillermo Gonzalez-Alatorre, Auteur Année de publication : 2012 Article en page(s) : pp. 5922–5931 Note générale : Industrial chemistry Langues : Anglais (eng) Mots-clés : Pollutant treatment Optimization Résumé : Pollutant trading adds flexibility to the pollution abatement decision making and introduces a new alternative to policy makers and industries. The overall goal is to meet environmental conditions equal or better than those obtained through the implementation of pollutant treatment technologies, but at a lower cost. This work proposes optimization models that can guide industries in taking optimal decisions under the flexibility provided by the trading. The mathematical models, formulated as mixed-integer programming problems, are limited to watershed trading and have been implemented and solved through the GAMS modeling environment. Results include optimal decisions for each pollutant source in order to satisfy global environmental regulations. That is, either implementing one of the available pollution abatement technologies or attaining credits through trading. To assess the performance of the optimization models, we consider a mercury trading case study. A comparison among the nontrading solution and the solutions of the various pollution trading models is presented and analyzed. As the environmental constraints become more stringent, the value of the objective function (cost of technology implementation and fines) increases and the configuration of the required technologies changes to avoid high concentrations of pollutants presented in the various discharge points of the watershed. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie2009197
in Industrial & engineering chemistry research > Vol. 51 N° 17 (Mai 2012) . - pp. 5922–5931[article] A mathematical programming approach to pollution trading [texte imprimé] / Francisco Lopez-Villarreal, Auteur ; Vicente Rico-Ramirez, Auteur ; Guillermo Gonzalez-Alatorre, Auteur . - 2012 . - pp. 5922–5931.
Industrial chemistry
Langues : Anglais (eng)
in Industrial & engineering chemistry research > Vol. 51 N° 17 (Mai 2012) . - pp. 5922–5931
Mots-clés : Pollutant treatment Optimization Résumé : Pollutant trading adds flexibility to the pollution abatement decision making and introduces a new alternative to policy makers and industries. The overall goal is to meet environmental conditions equal or better than those obtained through the implementation of pollutant treatment technologies, but at a lower cost. This work proposes optimization models that can guide industries in taking optimal decisions under the flexibility provided by the trading. The mathematical models, formulated as mixed-integer programming problems, are limited to watershed trading and have been implemented and solved through the GAMS modeling environment. Results include optimal decisions for each pollutant source in order to satisfy global environmental regulations. That is, either implementing one of the available pollution abatement technologies or attaining credits through trading. To assess the performance of the optimization models, we consider a mercury trading case study. A comparison among the nontrading solution and the solutions of the various pollution trading models is presented and analyzed. As the environmental constraints become more stringent, the value of the objective function (cost of technology implementation and fines) increases and the configuration of the required technologies changes to avoid high concentrations of pollutants presented in the various discharge points of the watershed. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie2009197 Exemplaires
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Titre : Effect of high hydrostatic pressure treatment on the preservation of beef meat Type de document : texte imprimé Auteurs : Beatriz E. Sanchez-Basurto, Auteur ; Mariana Ramirez-Gilly, Auteur ; Alberto Tecante, Auteur Année de publication : 2012 Article en page(s) : pp. 5932–5938 Note générale : Industrial chemistry Langues : Anglais (eng) Mots-clés : Hydrostatic pressure Résumé : The effect of high hydrostatic pressure was investigated to determine the best treatment conditions to preserve beef meat. The meat was pressurized from 172 to 620 MPa for 1–5 min at 25 ± 2 °C. Intensive color degradation occurred above 345 MPa. No significant reduction in aerobic mesophilic count was observed below 310 MPa. Therefore, 310, 324, and 345 MPa were applied to the meat for 1 min. The pH, water-holding capacity, total volatile bases, CFU/g, color, texture, and tenderness of pressurized and unpressurized meats were assessed for 42 days, while meat was stored at 4 °C. Data showed that pressure treatment produced good results. The color, texture, and tenderness of treated and untreated meats were not statistically different (p > 0.05). High hydrostatic pressure preserved meat over a longer time period and is a promising technology for extending the shelf life of raw meat. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie200930a
in Industrial & engineering chemistry research > Vol. 51 N° 17 (Mai 2012) . - pp. 5932–5938[article] Effect of high hydrostatic pressure treatment on the preservation of beef meat [texte imprimé] / Beatriz E. Sanchez-Basurto, Auteur ; Mariana Ramirez-Gilly, Auteur ; Alberto Tecante, Auteur . - 2012 . - pp. 5932–5938.
Industrial chemistry
Langues : Anglais (eng)
in Industrial & engineering chemistry research > Vol. 51 N° 17 (Mai 2012) . - pp. 5932–5938
Mots-clés : Hydrostatic pressure Résumé : The effect of high hydrostatic pressure was investigated to determine the best treatment conditions to preserve beef meat. The meat was pressurized from 172 to 620 MPa for 1–5 min at 25 ± 2 °C. Intensive color degradation occurred above 345 MPa. No significant reduction in aerobic mesophilic count was observed below 310 MPa. Therefore, 310, 324, and 345 MPa were applied to the meat for 1 min. The pH, water-holding capacity, total volatile bases, CFU/g, color, texture, and tenderness of pressurized and unpressurized meats were assessed for 42 days, while meat was stored at 4 °C. Data showed that pressure treatment produced good results. The color, texture, and tenderness of treated and untreated meats were not statistically different (p > 0.05). High hydrostatic pressure preserved meat over a longer time period and is a promising technology for extending the shelf life of raw meat. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie200930a Exemplaires
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Titre : Chitosan supported onto agave fiber — postconsumer HDPE composites for Cr(VI) adsorption Type de document : texte imprimé Auteurs : A. Alejandra Pérez-Fonseca, Auteur ; Cesar Gomez, Auteur ; Haydeé Dávila, Auteur Année de publication : 2012 Article en page(s) : pp. 5939–5946 Note générale : Industrial chemistry Langues : Anglais (eng) Mots-clés : Fibers Adsorbent kinetic models Résumé : Composites of high-density polyethylene and agave fibers coated with chitosan were used as adsorbent for Cr(VI). The adsorptions were made in batch and continuous systems. Different kinetic models were used to characterize the batch adsorption and to determine the adsorption capacity of the compound. To test the composite regeneration/reuse capability, the chromium content in the composite material was desorbed using different acids. The coated composites were characterized by scanning electron microscopy (SEM), attenuated total reflectance infrared spectroscopy (ATR-IR), and X-ray photoelectric spectroscopy (XPS). From the results it was found that the composite has a maximum adsorption capacity of 200 mg Cr(VI)/g of chitosan at pH 4. Sulfuric acid proved to be a good desorbent of Cr(VI), allowing the material to be reused while keeping its adsorption properties. Finally, the results showed that the continuous system has higher sorption capacity than the batch system; it was determined that the system needs a minimum retention time of 20 min in order to use the material in the treatment of contaminated effluents. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie201242x
in Industrial & engineering chemistry research > Vol. 51 N° 17 (Mai 2012) . - pp. 5939–5946[article] Chitosan supported onto agave fiber — postconsumer HDPE composites for Cr(VI) adsorption [texte imprimé] / A. Alejandra Pérez-Fonseca, Auteur ; Cesar Gomez, Auteur ; Haydeé Dávila, Auteur . - 2012 . - pp. 5939–5946.
Industrial chemistry
Langues : Anglais (eng)
in Industrial & engineering chemistry research > Vol. 51 N° 17 (Mai 2012) . - pp. 5939–5946
Mots-clés : Fibers Adsorbent kinetic models Résumé : Composites of high-density polyethylene and agave fibers coated with chitosan were used as adsorbent for Cr(VI). The adsorptions were made in batch and continuous systems. Different kinetic models were used to characterize the batch adsorption and to determine the adsorption capacity of the compound. To test the composite regeneration/reuse capability, the chromium content in the composite material was desorbed using different acids. The coated composites were characterized by scanning electron microscopy (SEM), attenuated total reflectance infrared spectroscopy (ATR-IR), and X-ray photoelectric spectroscopy (XPS). From the results it was found that the composite has a maximum adsorption capacity of 200 mg Cr(VI)/g of chitosan at pH 4. Sulfuric acid proved to be a good desorbent of Cr(VI), allowing the material to be reused while keeping its adsorption properties. Finally, the results showed that the continuous system has higher sorption capacity than the batch system; it was determined that the system needs a minimum retention time of 20 min in order to use the material in the treatment of contaminated effluents. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie201242x Exemplaires
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Titre : Evaluation of the effect of the rotational electrode speed in an electrochemical reactor using computational fluid dynamics (CFD) analysis Type de document : texte imprimé Auteurs : Helvio R. Mollinedo-Ponce-de-León, Auteur ; Sergio A. Martinez-Delgadillo, Auteur ; Víctor X. Mendoza-Escamilla, Auteur Année de publication : 2012 Article en page(s) : pp. 5947–5952 Note générale : Industrial chemistry Langues : Anglais (eng) Mots-clés : Electrode Fluid dynamics Résumé : High concentrations of hexavalent chromium (Cr(VI)), which is a hazardous substance, can be found in the wastewaters generated by the electroplating industry. High-cost treatments have been applied to remove Cr(VI) from industrial wastewaters. Simple treatments such as chemical precipitation methods use great quantities of chemical and flocculating agents that produce large quantities of sludge, which, in turn, must be treated, handled, and disposed, thus increasing the process costs. The electrochemical process is an alternative method to remove Cr(VI) from industrial wastewaters. During the process, a film of oxides is formed on the surface of the electrodes (passivation effect), reducing both the Fe(II) transfer to the bulk liquid and the process efficiency, while increasing the energy consumption. In this work, rotating electrodes were used to increase the mass transfer of Fe(II) to the bulk liquid and avoid the salt film formation on the electrodes. Using industrial wastewater, different electrode rotating rates were tested and their effect on the treatment time was measured. The turbulence intensity was evaluated by computational fluid dynamics (CFD) analysis. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie201782m
in Industrial & engineering chemistry research > Vol. 51 N° 17 (Mai 2012) . - pp. 5947–5952[article] Evaluation of the effect of the rotational electrode speed in an electrochemical reactor using computational fluid dynamics (CFD) analysis [texte imprimé] / Helvio R. Mollinedo-Ponce-de-León, Auteur ; Sergio A. Martinez-Delgadillo, Auteur ; Víctor X. Mendoza-Escamilla, Auteur . - 2012 . - pp. 5947–5952.
Industrial chemistry
Langues : Anglais (eng)
in Industrial & engineering chemistry research > Vol. 51 N° 17 (Mai 2012) . - pp. 5947–5952
Mots-clés : Electrode Fluid dynamics Résumé : High concentrations of hexavalent chromium (Cr(VI)), which is a hazardous substance, can be found in the wastewaters generated by the electroplating industry. High-cost treatments have been applied to remove Cr(VI) from industrial wastewaters. Simple treatments such as chemical precipitation methods use great quantities of chemical and flocculating agents that produce large quantities of sludge, which, in turn, must be treated, handled, and disposed, thus increasing the process costs. The electrochemical process is an alternative method to remove Cr(VI) from industrial wastewaters. During the process, a film of oxides is formed on the surface of the electrodes (passivation effect), reducing both the Fe(II) transfer to the bulk liquid and the process efficiency, while increasing the energy consumption. In this work, rotating electrodes were used to increase the mass transfer of Fe(II) to the bulk liquid and avoid the salt film formation on the electrodes. Using industrial wastewater, different electrode rotating rates were tested and their effect on the treatment time was measured. The turbulence intensity was evaluated by computational fluid dynamics (CFD) analysis. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie201782m Exemplaires
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Titre : Electrochemical decoloration of synthetic wastewater containing rhodamine 6G : Behaviors and mechanism Type de document : texte imprimé Auteurs : Yu-Ming Zheng, Auteur ; Rita Farida Yunus, Auteur ; K.G. Nadeeshani Nanayakkara, Auteur Année de publication : 2012 Article en page(s) : pp. 5953–5960 Note générale : Industrial chemistry Langues : Anglais (eng) Mots-clés : Electrochemical Wastewater Rhodamine Résumé : Dye wastewater has posed a great threat to our aqueous environment. In this study, the treatment of synthetic wastewater containing Rhodamine 6G by electrochemical technology using RuO2-coated Ti mesh as anode was investigated. The effects of solution pH, temperature, and dye auxiliaries on the performance were investigated. Carbon and nitrogen mass balance analyses, UV–vis spectroscopy, Fourier transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS), and cyclic voltammetry (CV) were used to elucidate the working mechanism. It was found that lower solution pH and lower temperature facilitated the decoloration of the wastewater. The addition of dye auxiliaries did not significantly affect the decoloration. Under optimal condition, complete decoloration of the synthetic wastewater was obtained within 5 min, and 42.3% of the dye was mineralized. The amine and methyl groups were first detached from the dye molecule, leading to a change in the dye structure from polar into nonpolar to form a water insoluble substance. The insoluble substances were floated by the hydrogen bubbles that were generated from the cathode to produce foam products. On the other hand, the soluble substances that remained in the solution were mineralized via indirect electro-oxidation by active chlorine generated by the anode. A conceptual model for the electrochemical treatment of Rhodamine 6G containing water was proposed to illustrate the mechanism of decoloration. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie2019273
in Industrial & engineering chemistry research > Vol. 51 N° 17 (Mai 2012) . - pp. 5953–5960[article] Electrochemical decoloration of synthetic wastewater containing rhodamine 6G : Behaviors and mechanism [texte imprimé] / Yu-Ming Zheng, Auteur ; Rita Farida Yunus, Auteur ; K.G. Nadeeshani Nanayakkara, Auteur . - 2012 . - pp. 5953–5960.
Industrial chemistry
Langues : Anglais (eng)
in Industrial & engineering chemistry research > Vol. 51 N° 17 (Mai 2012) . - pp. 5953–5960
Mots-clés : Electrochemical Wastewater Rhodamine Résumé : Dye wastewater has posed a great threat to our aqueous environment. In this study, the treatment of synthetic wastewater containing Rhodamine 6G by electrochemical technology using RuO2-coated Ti mesh as anode was investigated. The effects of solution pH, temperature, and dye auxiliaries on the performance were investigated. Carbon and nitrogen mass balance analyses, UV–vis spectroscopy, Fourier transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS), and cyclic voltammetry (CV) were used to elucidate the working mechanism. It was found that lower solution pH and lower temperature facilitated the decoloration of the wastewater. The addition of dye auxiliaries did not significantly affect the decoloration. Under optimal condition, complete decoloration of the synthetic wastewater was obtained within 5 min, and 42.3% of the dye was mineralized. The amine and methyl groups were first detached from the dye molecule, leading to a change in the dye structure from polar into nonpolar to form a water insoluble substance. The insoluble substances were floated by the hydrogen bubbles that were generated from the cathode to produce foam products. On the other hand, the soluble substances that remained in the solution were mineralized via indirect electro-oxidation by active chlorine generated by the anode. A conceptual model for the electrochemical treatment of Rhodamine 6G containing water was proposed to illustrate the mechanism of decoloration. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie2019273 Exemplaires
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Titre : Electrically conductive films made of pyrrole - formyl pyrrole by straightforward chemical copolymerization Type de document : texte imprimé Auteurs : Yusuke Hoshina, Auteur ; Takaomi Kobayashi, Auteur Année de publication : 2012 Article en page(s) : pp. 5961–5966 Note générale : Industrial chemistry Langues : Anglais (eng) Mots-clés : Electrically Films Copolymerization Pyrrole Résumé : Electrically conductive films were prepared by copolymerization of pyrrole (Py) and 2-formyl pyrrole (FPy) in the presence of trifluoroacetic acid (TFA) used as a catalyst in chloroform. Formation of the copolymer P(Py-co-FPy) films was examined, when the FPy monomer mole fractions was changed. The obtained films showed a metallic greenish black color and had electrical conductivity of 10–4 to 10–1 S/cm when I2 was doped in the copolymer films. As the mole fraction of the FPy increased from 0 to 0.5, the tensile strength of the films increased from 11.1 to 81.3 N/mm2. For analysis of the copolymerization, 1H NMR in deuterated chloroform was measured and the evidence was revealed that the formyl group of FPy was attacked by the acid catalyst before the copolymerization started. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie300181s
in Industrial & engineering chemistry research > Vol. 51 N° 17 (Mai 2012) . - pp. 5961–5966[article] Electrically conductive films made of pyrrole - formyl pyrrole by straightforward chemical copolymerization [texte imprimé] / Yusuke Hoshina, Auteur ; Takaomi Kobayashi, Auteur . - 2012 . - pp. 5961–5966.
Industrial chemistry
Langues : Anglais (eng)
in Industrial & engineering chemistry research > Vol. 51 N° 17 (Mai 2012) . - pp. 5961–5966
Mots-clés : Electrically Films Copolymerization Pyrrole Résumé : Electrically conductive films were prepared by copolymerization of pyrrole (Py) and 2-formyl pyrrole (FPy) in the presence of trifluoroacetic acid (TFA) used as a catalyst in chloroform. Formation of the copolymer P(Py-co-FPy) films was examined, when the FPy monomer mole fractions was changed. The obtained films showed a metallic greenish black color and had electrical conductivity of 10–4 to 10–1 S/cm when I2 was doped in the copolymer films. As the mole fraction of the FPy increased from 0 to 0.5, the tensile strength of the films increased from 11.1 to 81.3 N/mm2. For analysis of the copolymerization, 1H NMR in deuterated chloroform was measured and the evidence was revealed that the formyl group of FPy was attacked by the acid catalyst before the copolymerization started. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie300181s Exemplaires
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Titre : Experimental investigation of the formation of cyclopentane - methane hydrate in a novel and large - size bubble column reactor Type de document : texte imprimé Auteurs : Qiu-Nan Lv, Auteur ; Xiao-Sen Li, Auteur ; Chun-Gang Xu, Auteur Année de publication : 2012 Article en page(s) : pp. 5967–5975 Note générale : Industrial chemistry Langues : Anglais (eng) Mots-clés : Methane gas Résumé : The effects of the flow rates of cyclopentane (CP) and methane gas, operating pressure, and experimental temperature on the formation of cyclopentane-methane hydrate were investigated using a novel bubble column reactor. The results indicated that, with either an increase of the operating pressure or a decrease of the experimental temperature, the induction time decreased whereas the cumulative gas consumption and gas conversion ratio increased. In addition, with an increase of the flow rate of methane gas, the induction time decreased, whereas the cumulative gas consumption increased. The gas conversion ratio increased first from 61.5% to 93.1% when the flow rate of methane gas increased from 159 to 234 mL/min and then decreased from 93.1% to 83.2% when the flow rate of methane gas continuously increased from 234 mL/min to 308.9 mL/min. This decrease was attributed to an increase of the discharge rate of methane from the reactor. It was noted the average methane consumption rate could be effectively enhanced with an increase of the flow rate of gas at relatively low pressure and high temperature. The flow rate of CP had a minimal effect on the cumulative gas consumption and gas conversion ratio. However, an increase of the flow rate of CP could reduce the induction time. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie202422c
in Industrial & engineering chemistry research > Vol. 51 N° 17 (Mai 2012) . - pp. 5967–5975[article] Experimental investigation of the formation of cyclopentane - methane hydrate in a novel and large - size bubble column reactor [texte imprimé] / Qiu-Nan Lv, Auteur ; Xiao-Sen Li, Auteur ; Chun-Gang Xu, Auteur . - 2012 . - pp. 5967–5975.
Industrial chemistry
Langues : Anglais (eng)
in Industrial & engineering chemistry research > Vol. 51 N° 17 (Mai 2012) . - pp. 5967–5975
Mots-clés : Methane gas Résumé : The effects of the flow rates of cyclopentane (CP) and methane gas, operating pressure, and experimental temperature on the formation of cyclopentane-methane hydrate were investigated using a novel bubble column reactor. The results indicated that, with either an increase of the operating pressure or a decrease of the experimental temperature, the induction time decreased whereas the cumulative gas consumption and gas conversion ratio increased. In addition, with an increase of the flow rate of methane gas, the induction time decreased, whereas the cumulative gas consumption increased. The gas conversion ratio increased first from 61.5% to 93.1% when the flow rate of methane gas increased from 159 to 234 mL/min and then decreased from 93.1% to 83.2% when the flow rate of methane gas continuously increased from 234 mL/min to 308.9 mL/min. This decrease was attributed to an increase of the discharge rate of methane from the reactor. It was noted the average methane consumption rate could be effectively enhanced with an increase of the flow rate of gas at relatively low pressure and high temperature. The flow rate of CP had a minimal effect on the cumulative gas consumption and gas conversion ratio. However, an increase of the flow rate of CP could reduce the induction time. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie202422c Exemplaires
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Titre : Characterization and antimicrobial properties of silver and silver oxide Nanoparticles synthesized by cell - free extract of amangrove - associated pseudomonas aeruginosa M6 using two different thermal treatments Type de document : texte imprimé Auteurs : Seenivasan Boopathi, Auteur ; Selvaraj Gopinath, Auteur ; Thangavelu Boopathi, Auteur Année de publication : 2012 Article en page(s) : pp. 5976–5985 Note générale : Industrial chemistry Langues : Anglais (eng) Mots-clés : Nanoparticles Antimicrobial Oxide Résumé : Synthesis of silver nanoparticles by cell-free extract (CFE) of Pseudomonas aeruginosa M6 isolated from a mangrove ecosystem was demonstrated using two physical methods, namely, boiling (conventional thermal treatment (CTT)) and microwave treatment (MWT) at pH 9. X-ray diffraction (XRD) analysis revealed the presence of smaller (10.4 nm), pure silver nanoparticles synthesized via CTT (C-NPs) and larger silver oxide nanoparticles in majority with negligible concentration of pure silver particles by MWT. Transmission electron microscopy (TEM) analysis showed that C-NPs are spherical in shape. Atomic force microscopy (AFM) analysis also confirmed the presence of large-sized, aggregated nanoparticles synthesized via MWT (M-NPs). Electrophoresis indicated the size and charge-based mobility in agarose gel (0.4%), wherein the C-NPs moved faster than M-NPs, because of their relatively smaller size. The zeta potential value of C-NPs and M-NPs was found to be −30.1 mV and −23.1 mV, respectively. Fourier transform infrared (FT-IR) results revealed that both C-NPs and M-NPs were capped with proteins, but with different conformations. Furthermore, TEM analysis of bacterial cells exposed to aqueous silver nitrate showed the presence of spherical silver nanoparticles accumulated in periplasmic space, indicating the possible involvement of periplasmic nitrate reductase in this process. In addition, both C-NPs and M-NPs have also shown good antibacterial and anticandidal activities. Thus, marine Pseudomonas aeruginosa M6 can be a potential source for the synthesis of silver nanoparticles. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie3001869
in Industrial & engineering chemistry research > Vol. 51 N° 17 (Mai 2012) . - pp. 5976–5985[article] Characterization and antimicrobial properties of silver and silver oxide Nanoparticles synthesized by cell - free extract of amangrove - associated pseudomonas aeruginosa M6 using two different thermal treatments [texte imprimé] / Seenivasan Boopathi, Auteur ; Selvaraj Gopinath, Auteur ; Thangavelu Boopathi, Auteur . - 2012 . - pp. 5976–5985.
Industrial chemistry
Langues : Anglais (eng)
in Industrial & engineering chemistry research > Vol. 51 N° 17 (Mai 2012) . - pp. 5976–5985
Mots-clés : Nanoparticles Antimicrobial Oxide Résumé : Synthesis of silver nanoparticles by cell-free extract (CFE) of Pseudomonas aeruginosa M6 isolated from a mangrove ecosystem was demonstrated using two physical methods, namely, boiling (conventional thermal treatment (CTT)) and microwave treatment (MWT) at pH 9. X-ray diffraction (XRD) analysis revealed the presence of smaller (10.4 nm), pure silver nanoparticles synthesized via CTT (C-NPs) and larger silver oxide nanoparticles in majority with negligible concentration of pure silver particles by MWT. Transmission electron microscopy (TEM) analysis showed that C-NPs are spherical in shape. Atomic force microscopy (AFM) analysis also confirmed the presence of large-sized, aggregated nanoparticles synthesized via MWT (M-NPs). Electrophoresis indicated the size and charge-based mobility in agarose gel (0.4%), wherein the C-NPs moved faster than M-NPs, because of their relatively smaller size. The zeta potential value of C-NPs and M-NPs was found to be −30.1 mV and −23.1 mV, respectively. Fourier transform infrared (FT-IR) results revealed that both C-NPs and M-NPs were capped with proteins, but with different conformations. Furthermore, TEM analysis of bacterial cells exposed to aqueous silver nitrate showed the presence of spherical silver nanoparticles accumulated in periplasmic space, indicating the possible involvement of periplasmic nitrate reductase in this process. In addition, both C-NPs and M-NPs have also shown good antibacterial and anticandidal activities. Thus, marine Pseudomonas aeruginosa M6 can be a potential source for the synthesis of silver nanoparticles. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie3001869 Exemplaires
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Titre : Photodegradation of Toluene, m - xylene, and n - butyl acetate and their mixtures over TiO2 catalyst on glass fibers Type de document : texte imprimé Auteurs : Jordi Palau, Auteur ; Margarita Colomer, Auteur ; Josep M. Penya-Roja, Auteur Année de publication : 2012 Article en page(s) : pp. 5986–5994 Note générale : Industrial chemistry Langues : Anglais (eng) Mots-clés : Fiber glass Photodegradation Résumé : The abatement of typical paint solvent compounds as individuals and in mixtures was carried out in an annular TiO2 supported reactor, for concentrations up to 900 mg C m–3. Two different fiberglass supports were compared, and the catalyst supported over a fiber mat showed better performance, with a lower pressure drop (>35% of reduction) and a slightly higher removal efficiency (about 2%) than that supported over glass wool. For every target compound in the whole range of relative humidity studied (4–75%), the photocatalytic activity increased with the air water content. The removal of the compounds in the binary and ternary mixtures was depressed, even >90% for toluene, compared with individual tests. Xylene was the main compound responsible for the inhibition effects in the mixtures, followed by toluene and butyl acetate. Photodegradation of individual compound data was well fitted by both simple and bimolecular Langmuir–Hinselwood (LH) kinetic models. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie300357x
in Industrial & engineering chemistry research > Vol. 51 N° 17 (Mai 2012) . - pp. 5986–5994[article] Photodegradation of Toluene, m - xylene, and n - butyl acetate and their mixtures over TiO2 catalyst on glass fibers [texte imprimé] / Jordi Palau, Auteur ; Margarita Colomer, Auteur ; Josep M. Penya-Roja, Auteur . - 2012 . - pp. 5986–5994.
Industrial chemistry
Langues : Anglais (eng)
in Industrial & engineering chemistry research > Vol. 51 N° 17 (Mai 2012) . - pp. 5986–5994
Mots-clés : Fiber glass Photodegradation Résumé : The abatement of typical paint solvent compounds as individuals and in mixtures was carried out in an annular TiO2 supported reactor, for concentrations up to 900 mg C m–3. Two different fiberglass supports were compared, and the catalyst supported over a fiber mat showed better performance, with a lower pressure drop (>35% of reduction) and a slightly higher removal efficiency (about 2%) than that supported over glass wool. For every target compound in the whole range of relative humidity studied (4–75%), the photocatalytic activity increased with the air water content. The removal of the compounds in the binary and ternary mixtures was depressed, even >90% for toluene, compared with individual tests. Xylene was the main compound responsible for the inhibition effects in the mixtures, followed by toluene and butyl acetate. Photodegradation of individual compound data was well fitted by both simple and bimolecular Langmuir–Hinselwood (LH) kinetic models. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie300357x Exemplaires
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Titre : Synthesis of fluorescent CdS quantum dots of tunable light emission with a new in situ produced capping agent Type de document : texte imprimé Auteurs : Yan-mei Mo, Auteur ; Yu Tang, Auteur ; Fei Gao, Auteur Année de publication : 2012 Article en page(s) : pp. 5995–6000 Note générale : Industrial chemistry Langues : Anglais (eng) Mots-clés : Carboxylic acid Résumé : Herein, we report an ambient synthesis of CdS QDs with widely tunable particle size by sulfur source of H2S and a new capping agent R-2-thiotetrahydrothiazole-4-carboxylic acid in situ produced from the reaction of l-cysteine with carbon disulfide in water. XRD, FTIR, UV–vis, PL, and TEM measurements were used to characterize the synthesized CdS QDs. Small particle size in a range of 1–3 nm and five PL colors from dark, deep blue to yellow of CdS QDs were achieved by changing the molar ratio and pH value of preparation. These CdS colloid solutions exhibit high stability even under weak acidity conditions at pH 6.5. The CdS QDs display highest emission intensity at a concentration of 2 mM. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie201826e
in Industrial & engineering chemistry research > Vol. 51 N° 17 (Mai 2012) . - pp. 5995–6000[article] Synthesis of fluorescent CdS quantum dots of tunable light emission with a new in situ produced capping agent [texte imprimé] / Yan-mei Mo, Auteur ; Yu Tang, Auteur ; Fei Gao, Auteur . - 2012 . - pp. 5995–6000.
Industrial chemistry
Langues : Anglais (eng)
in Industrial & engineering chemistry research > Vol. 51 N° 17 (Mai 2012) . - pp. 5995–6000
Mots-clés : Carboxylic acid Résumé : Herein, we report an ambient synthesis of CdS QDs with widely tunable particle size by sulfur source of H2S and a new capping agent R-2-thiotetrahydrothiazole-4-carboxylic acid in situ produced from the reaction of l-cysteine with carbon disulfide in water. XRD, FTIR, UV–vis, PL, and TEM measurements were used to characterize the synthesized CdS QDs. Small particle size in a range of 1–3 nm and five PL colors from dark, deep blue to yellow of CdS QDs were achieved by changing the molar ratio and pH value of preparation. These CdS colloid solutions exhibit high stability even under weak acidity conditions at pH 6.5. The CdS QDs display highest emission intensity at a concentration of 2 mM. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie201826e Exemplaires
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Titre : Fouling and corrosion properties of SiO2 coatings on copper in geothermal water Type de document : texte imprimé Auteurs : Chen Ning, Auteur ; Liu Mingyan, Auteur ; Zhou Weidong, Auteur Année de publication : 2012 Article en page(s) : pp. 6001–6017 Note générale : Industrial chemistry Langues : Anglais (eng) Mots-clés : Geothermal utilization Corrosion Silica coatings Résumé : Two critical problems in geothermal utilization are corrosion and fouling on the surfaces of plants and fittings, and use of surface coatings is a good method to overcome such difficulties. Silica coatings with film thickness of several hundred nanometers on copper substrates were prepared by the liquid-phase deposition technique and characterized with respect to surface morphology, composition, surface free energy, roughness, and film thickness. Examinations of both fouling in calcium carbonate solution and corrosion in corrosive geothermal water on the surfaces of SiO2-coated samples were performed. The results showed that the fouling rate on the SiO2-coated surface was obviously reduced compared with that on the polished surface. Moreover, the inhibition of corrosion on the modified surface was found even though, after a long immersion time, the corrosion resistance action decreased because of the surface peeling of SiO2-coated samples. The corrosion behavior of the SiO2 coating was further studied with electrochemical measurements by electrochemical impedance spectroscopy. This work suggests a new possibility for solving the fouling and corrosion issues encountered in the use of geothermal water. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie202091b
in Industrial & engineering chemistry research > Vol. 51 N° 17 (Mai 2012) . - pp. 6001–6017[article] Fouling and corrosion properties of SiO2 coatings on copper in geothermal water [texte imprimé] / Chen Ning, Auteur ; Liu Mingyan, Auteur ; Zhou Weidong, Auteur . - 2012 . - pp. 6001–6017.
Industrial chemistry
Langues : Anglais (eng)
in Industrial & engineering chemistry research > Vol. 51 N° 17 (Mai 2012) . - pp. 6001–6017
Mots-clés : Geothermal utilization Corrosion Silica coatings Résumé : Two critical problems in geothermal utilization are corrosion and fouling on the surfaces of plants and fittings, and use of surface coatings is a good method to overcome such difficulties. Silica coatings with film thickness of several hundred nanometers on copper substrates were prepared by the liquid-phase deposition technique and characterized with respect to surface morphology, composition, surface free energy, roughness, and film thickness. Examinations of both fouling in calcium carbonate solution and corrosion in corrosive geothermal water on the surfaces of SiO2-coated samples were performed. The results showed that the fouling rate on the SiO2-coated surface was obviously reduced compared with that on the polished surface. Moreover, the inhibition of corrosion on the modified surface was found even though, after a long immersion time, the corrosion resistance action decreased because of the surface peeling of SiO2-coated samples. The corrosion behavior of the SiO2 coating was further studied with electrochemical measurements by electrochemical impedance spectroscopy. This work suggests a new possibility for solving the fouling and corrosion issues encountered in the use of geothermal water. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie202091b Exemplaires
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Titre : Ecofriendly cold ramming paste for an aluminum electrolysis cell with furan resin as a binder Type de document : texte imprimé Auteurs : Lin Tian, Auteur ; Yang min Zhou, Auteur ; Gang Xie, Auteur Année de publication : 2012 Article en page(s) : pp. 6018–6024 Note générale : Industrial chemistry Langues : Anglais (eng) Mots-clés : Electrolysis cell Résumé : Cold ramming paste was synthesized with electro-calcined anthracite (ECA) and artificial graphite as an aggregate and furan resin as a binder. Properties of synthesized paste were investigated by Universal Testing Machine, thermogravimetry (TG) and gas chromatography (GC) mass spectrometry (MS). The results show that the synthesized paste is an ecofriendly material and that it has some superior physical properties such as low electrical resistivity, high compressive strength, appropriate sodium penetration, and thermal expansion, all of which can meet industry requirements. The TG curve of the paste can be divided into three stages and the lower heating rate should be used in the second stage. Moreover, the resin functional groups disappear more completely at higher carbonized temperature based on infrared (IR) spectrum analysis. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie202191y
in Industrial & engineering chemistry research > Vol. 51 N° 17 (Mai 2012) . - pp. 6018–6024[article] Ecofriendly cold ramming paste for an aluminum electrolysis cell with furan resin as a binder [texte imprimé] / Lin Tian, Auteur ; Yang min Zhou, Auteur ; Gang Xie, Auteur . - 2012 . - pp. 6018–6024.
Industrial chemistry
Langues : Anglais (eng)
in Industrial & engineering chemistry research > Vol. 51 N° 17 (Mai 2012) . - pp. 6018–6024
Mots-clés : Electrolysis cell Résumé : Cold ramming paste was synthesized with electro-calcined anthracite (ECA) and artificial graphite as an aggregate and furan resin as a binder. Properties of synthesized paste were investigated by Universal Testing Machine, thermogravimetry (TG) and gas chromatography (GC) mass spectrometry (MS). The results show that the synthesized paste is an ecofriendly material and that it has some superior physical properties such as low electrical resistivity, high compressive strength, appropriate sodium penetration, and thermal expansion, all of which can meet industry requirements. The TG curve of the paste can be divided into three stages and the lower heating rate should be used in the second stage. Moreover, the resin functional groups disappear more completely at higher carbonized temperature based on infrared (IR) spectrum analysis. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie202191y Exemplaires
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Titre : Influence of surface properties of coated papers on printed electronics Type de document : texte imprimé Auteurs : Petri Ihalainen, Auteur ; Anni Maattanen, Auteur ; Joakim Jarnstrom, Auteur Année de publication : 2012 Article en page(s) : pp. 6025–6036 Note générale : Industrial chemistry Langues : Anglais (eng) Mots-clés : Physical properties Résumé : Thin and narrow conductive patterns of metal (silver) and organic polymer (polyaniline) were printed on various coated paper samples. A detailed characterization of the physical properties (i.e., short length scale roughness, surface energy, and air permeability) of the paper samples was conducted. These properties were correlated with print quality (print resolution and edge waviness) and electrical performance (resistance) of the printed wires. A plastic film was used as a reference substrate. The print resolution and the magnitude of the edge waviness were affected by the complex interplay of different physical properties of both the substrate and the ink. On the other hand, the resistance of the printed wires was found to correlate linearly with the short length scale roughness of the print substrate. The electrical performance of the paper substrates showing the highest conductivity for the printed patterns was comparable to that of the plastic film. The paper substrate on which the printed wires showed the best electrical performance was used as a substrate for fabrication of an organic transistor with low operating voltage. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie202807v
in Industrial & engineering chemistry research > Vol. 51 N° 17 (Mai 2012) . - pp. 6025–6036[article] Influence of surface properties of coated papers on printed electronics [texte imprimé] / Petri Ihalainen, Auteur ; Anni Maattanen, Auteur ; Joakim Jarnstrom, Auteur . - 2012 . - pp. 6025–6036.
Industrial chemistry
Langues : Anglais (eng)
in Industrial & engineering chemistry research > Vol. 51 N° 17 (Mai 2012) . - pp. 6025–6036
Mots-clés : Physical properties Résumé : Thin and narrow conductive patterns of metal (silver) and organic polymer (polyaniline) were printed on various coated paper samples. A detailed characterization of the physical properties (i.e., short length scale roughness, surface energy, and air permeability) of the paper samples was conducted. These properties were correlated with print quality (print resolution and edge waviness) and electrical performance (resistance) of the printed wires. A plastic film was used as a reference substrate. The print resolution and the magnitude of the edge waviness were affected by the complex interplay of different physical properties of both the substrate and the ink. On the other hand, the resistance of the printed wires was found to correlate linearly with the short length scale roughness of the print substrate. The electrical performance of the paper substrates showing the highest conductivity for the printed patterns was comparable to that of the plastic film. The paper substrate on which the printed wires showed the best electrical performance was used as a substrate for fabrication of an organic transistor with low operating voltage. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie202807v Exemplaires
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Titre : Upgrading ash - rich activated carbon from distilled spirit lees Type de document : texte imprimé Auteurs : Juan Yang, Auteur ; Jian Yu, Auteur ; Wei Zhao, Auteur Année de publication : 2012 Article en page(s) : pp. 6037–6043 Note générale : Industrial chemistry Langues : Anglais (eng) Mots-clés : steam activated carbon Résumé : Activated carbon (AC) was prepared from ash-rich distilled spirit lees via carbonization and successive activation incorporated with different deashing methods. The results show that the alkali treatment of the steam-activated carbon (ATAC) produced the AC with the highest performance in comparison with the NaOH activation and direct alkali treatment of the carbonized carbon (ATCC). The ATAC removed 84.4% of the ash from steam-activated carbon and increased the BET surface area and total pore volume by 92.3% and 109.3%, respectively, resulting in the AC with its ash content of 11 wt %, BET surface area of 620 m2/g, and total pore volume of 0.67 cm3/g. The article also revealed that it is possible to use the alkaline leaching solution from the ATAC, which is mainly composed of sodium silicate, as the major binder to mold the produced powder AC. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie202882r
in Industrial & engineering chemistry research > Vol. 51 N° 17 (Mai 2012) . - pp. 6037–6043[article] Upgrading ash - rich activated carbon from distilled spirit lees [texte imprimé] / Juan Yang, Auteur ; Jian Yu, Auteur ; Wei Zhao, Auteur . - 2012 . - pp. 6037–6043.
Industrial chemistry
Langues : Anglais (eng)
in Industrial & engineering chemistry research > Vol. 51 N° 17 (Mai 2012) . - pp. 6037–6043
Mots-clés : steam activated carbon Résumé : Activated carbon (AC) was prepared from ash-rich distilled spirit lees via carbonization and successive activation incorporated with different deashing methods. The results show that the alkali treatment of the steam-activated carbon (ATAC) produced the AC with the highest performance in comparison with the NaOH activation and direct alkali treatment of the carbonized carbon (ATCC). The ATAC removed 84.4% of the ash from steam-activated carbon and increased the BET surface area and total pore volume by 92.3% and 109.3%, respectively, resulting in the AC with its ash content of 11 wt %, BET surface area of 620 m2/g, and total pore volume of 0.67 cm3/g. The article also revealed that it is possible to use the alkaline leaching solution from the ATAC, which is mainly composed of sodium silicate, as the major binder to mold the produced powder AC. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie202882r Exemplaires
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Titre : Magnetic CoFe2O4 – graphene hybrids : Facile synthesis, characterization, and catalytic properties Type de document : texte imprimé Auteurs : Yunjin Yao, Auteur ; Zeheng Yang, Auteur ; Dawei Zhang, Auteur Année de publication : 2012 Article en page(s) : pp. 6044–6051 Note générale : Industrial chemistry Langues : Anglais (eng) Mots-clés : Magnetic Graphene oxide Résumé : This paper reports the synthesis of magnetic CoFe2O4–reduced graphene oxide (rGO) hybrids and the catalytic performance in heterogeneous activation of peroxymonosulfate (PMS) for decomposition of phenol. The surface morphologies and structures of the CoFe2O4–rGO hybrids were investigated by field emission scanning electron microscopy (SEM), energy-dispersive X-ray spectrometer (EDS), transmission electron microscopies(TEM), powder X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), nitrogen adsorption–desorption isotherm, and thermogravimetric analysis (TGA). Through an in situ chemical deposition and reduction, CoFe2O4–rGO hybrids with CoFe2O4 nanoparticles of 23.8 nm were produced. Catalytic testing showed CoFe2O4–rGO hybrids exhibited much better catalytic activity than CoFe2O4, which suggests rGO plays an important role in CoFe2O4–rGO hybrids for the decomposition of phenol. Moreover, the hybrid catalyst presents good magnetism and could be separated from solution by a magnet. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie300271p
in Industrial & engineering chemistry research > Vol. 51 N° 17 (Mai 2012) . - pp. 6044–6051[article] Magnetic CoFe2O4 – graphene hybrids : Facile synthesis, characterization, and catalytic properties [texte imprimé] / Yunjin Yao, Auteur ; Zeheng Yang, Auteur ; Dawei Zhang, Auteur . - 2012 . - pp. 6044–6051.
Industrial chemistry
Langues : Anglais (eng)
in Industrial & engineering chemistry research > Vol. 51 N° 17 (Mai 2012) . - pp. 6044–6051
Mots-clés : Magnetic Graphene oxide Résumé : This paper reports the synthesis of magnetic CoFe2O4–reduced graphene oxide (rGO) hybrids and the catalytic performance in heterogeneous activation of peroxymonosulfate (PMS) for decomposition of phenol. The surface morphologies and structures of the CoFe2O4–rGO hybrids were investigated by field emission scanning electron microscopy (SEM), energy-dispersive X-ray spectrometer (EDS), transmission electron microscopies(TEM), powder X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), nitrogen adsorption–desorption isotherm, and thermogravimetric analysis (TGA). Through an in situ chemical deposition and reduction, CoFe2O4–rGO hybrids with CoFe2O4 nanoparticles of 23.8 nm were produced. Catalytic testing showed CoFe2O4–rGO hybrids exhibited much better catalytic activity than CoFe2O4, which suggests rGO plays an important role in CoFe2O4–rGO hybrids for the decomposition of phenol. Moreover, the hybrid catalyst presents good magnetism and could be separated from solution by a magnet. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie300271p Exemplaires
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Titre : Synthesis and characterization of gallic acid resin and its interaction with palladium(II), rhodium(III) chloro complexes Type de document : texte imprimé Auteurs : Mustafa Can, Auteur ; Emrah Bulut, Auteur ; Mahmut Özacar, Auteur Année de publication : 2012 Article en page(s) : pp. 6052–6063 Note générale : Industrial chemistry Langues : Anglais (eng) Mots-clés : Gallic acid Adsorbent Résumé : Gallic acid (GA) and formaldehyde condensation reaction was carried out under alkaline condition to prepare the gallic acid–formaldehyde resol resin (GAR). Obtained resin was used as adsorbent for recovery of palladium(II) and rhodium(III) ions from chloride-containing solutions. This kind of recovery was very simple and useful for generating little secondary wastes. Interaction of adsorption also was investigated: Chloropalladium(II) species were reduced to Pd(0), while hydroxyl groups of GAR were oxidized during the adsorption. Proposed adsorption of the aquachlororhodium(III) species mostly takes place via ligand exchange mechanism. GAR, Rh-adsorbed GAR, and Pd-adsorbed GAR were characterized by scanning electron microscopy, energy-dispersive spectrometry, X-ray diffraction spectroscopy, and Fourier transform infrared–attenuated total reflection spectroscopy. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie300437u
in Industrial & engineering chemistry research > Vol. 51 N° 17 (Mai 2012) . - pp. 6052–6063[article] Synthesis and characterization of gallic acid resin and its interaction with palladium(II), rhodium(III) chloro complexes [texte imprimé] / Mustafa Can, Auteur ; Emrah Bulut, Auteur ; Mahmut Özacar, Auteur . - 2012 . - pp. 6052–6063.
Industrial chemistry
Langues : Anglais (eng)
in Industrial & engineering chemistry research > Vol. 51 N° 17 (Mai 2012) . - pp. 6052–6063
Mots-clés : Gallic acid Adsorbent Résumé : Gallic acid (GA) and formaldehyde condensation reaction was carried out under alkaline condition to prepare the gallic acid–formaldehyde resol resin (GAR). Obtained resin was used as adsorbent for recovery of palladium(II) and rhodium(III) ions from chloride-containing solutions. This kind of recovery was very simple and useful for generating little secondary wastes. Interaction of adsorption also was investigated: Chloropalladium(II) species were reduced to Pd(0), while hydroxyl groups of GAR were oxidized during the adsorption. Proposed adsorption of the aquachlororhodium(III) species mostly takes place via ligand exchange mechanism. GAR, Rh-adsorbed GAR, and Pd-adsorbed GAR were characterized by scanning electron microscopy, energy-dispersive spectrometry, X-ray diffraction spectroscopy, and Fourier transform infrared–attenuated total reflection spectroscopy. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie300437u Exemplaires
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Titre : Multiobjective control structure design : A branch and bound approach Type de document : texte imprimé Auteurs : Vinay Kariwala, Auteur ; Yi Cao, Auteur Année de publication : 2012 Article en page(s) : pp. 6064–6070 Note générale : Industrial chemistry Langues : Anglais (eng) Mots-clés : Multiobjective optimization Résumé : Control structure design traditionally involves two steps of selections, namely the selection of controlled and manipulated variables and the selection of pairings interconnecting these variables. The available criteria for both selections require enumeration of every alternative. Hence, an exhaustive search can be computationally forbidding for large-scale processes. On the other hand, owing to the computational complexity, variables and pairings are often selected sequentially, which may result in suboptimal control structures. In this paper, an efficient branch and bound (BAB) method is proposed to select the variables and pairings together in a multiobjective optimization framework. As an illustration of the proposed multiobjective BAB framework, the minimum singular value rule and the μ-interaction measure are used as the criteria for selection of controlled variables and pairings, respectively. Numerical tests using randomly generated matrices and the large-scale case study of hydrodealkylation of toluene (HDA) process show that the BAB method is able to reduce the solution time by several orders of magnitude in comparison with exhaustive search. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie201510c
in Industrial & engineering chemistry research > Vol. 51 N° 17 (Mai 2012) . - pp. 6064–6070[article] Multiobjective control structure design : A branch and bound approach [texte imprimé] / Vinay Kariwala, Auteur ; Yi Cao, Auteur . - 2012 . - pp. 6064–6070.
Industrial chemistry
Langues : Anglais (eng)
in Industrial & engineering chemistry research > Vol. 51 N° 17 (Mai 2012) . - pp. 6064–6070
Mots-clés : Multiobjective optimization Résumé : Control structure design traditionally involves two steps of selections, namely the selection of controlled and manipulated variables and the selection of pairings interconnecting these variables. The available criteria for both selections require enumeration of every alternative. Hence, an exhaustive search can be computationally forbidding for large-scale processes. On the other hand, owing to the computational complexity, variables and pairings are often selected sequentially, which may result in suboptimal control structures. In this paper, an efficient branch and bound (BAB) method is proposed to select the variables and pairings together in a multiobjective optimization framework. As an illustration of the proposed multiobjective BAB framework, the minimum singular value rule and the μ-interaction measure are used as the criteria for selection of controlled variables and pairings, respectively. Numerical tests using randomly generated matrices and the large-scale case study of hydrodealkylation of toluene (HDA) process show that the BAB method is able to reduce the solution time by several orders of magnitude in comparison with exhaustive search. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie201510c Exemplaires
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Titre : Hybrid derivative dynamic time warping for online industrial batch - end quality estimation Type de document : texte imprimé Auteurs : Geert Gins, Auteur ; Pieter Van den Kerkhof, Auteur ; Jan F. M. Van Impe, Auteur Année de publication : 2012 Article en page(s) : pp. 6071–6084 Note générale : Industrial chemistry Langues : Anglais (eng) Mots-clés : Hybrid Industrial polymerization Résumé : This paper discusses the design of an inferential sensor for the online prediction of the end-quality of an industrial batch polymerization process. Owing to unequal batch speeds, measurement profiles must be synchronized before modeling. This makes profile alignment an integral part of any inferential sensor. In this work, a novel online hybrid derivative dynamic time warping data alignment technique is presented. The proposed technique allows for automatic adjustment of the warping resolution to achieve optimal alignment results for both slowly and rapidly varying parts of the measurement profiles. The proposed online data alignment technique is combined with a multiway partial least-squares black box model to yield online predictions of the final quality of a running batch process. It is demonstrated that this inferential sensor is capable of accurately predicting the quality online for an industrial polymerization process, even when the production process is only halfway, that is, well before lab measurements become available. As a result of this early warning, batches violating the quality specifications can be corrected or even stopped. This leads to fewer off-spec batches, saves production time, lowers operational costs, and reduces waste material and energy. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie2019068
in Industrial & engineering chemistry research > Vol. 51 N° 17 (Mai 2012) . - pp. 6071–6084[article] Hybrid derivative dynamic time warping for online industrial batch - end quality estimation [texte imprimé] / Geert Gins, Auteur ; Pieter Van den Kerkhof, Auteur ; Jan F. M. Van Impe, Auteur . - 2012 . - pp. 6071–6084.
Industrial chemistry
Langues : Anglais (eng)
in Industrial & engineering chemistry research > Vol. 51 N° 17 (Mai 2012) . - pp. 6071–6084
Mots-clés : Hybrid Industrial polymerization Résumé : This paper discusses the design of an inferential sensor for the online prediction of the end-quality of an industrial batch polymerization process. Owing to unequal batch speeds, measurement profiles must be synchronized before modeling. This makes profile alignment an integral part of any inferential sensor. In this work, a novel online hybrid derivative dynamic time warping data alignment technique is presented. The proposed technique allows for automatic adjustment of the warping resolution to achieve optimal alignment results for both slowly and rapidly varying parts of the measurement profiles. The proposed online data alignment technique is combined with a multiway partial least-squares black box model to yield online predictions of the final quality of a running batch process. It is demonstrated that this inferential sensor is capable of accurately predicting the quality online for an industrial polymerization process, even when the production process is only halfway, that is, well before lab measurements become available. As a result of this early warning, batches violating the quality specifications can be corrected or even stopped. This leads to fewer off-spec batches, saves production time, lowers operational costs, and reduces waste material and energy. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie2019068 Exemplaires
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Titre : A Multiperiod optimization model for hydrogen system scheduling in refinery Type de document : texte imprimé Auteurs : Yunqiang Jiao, Auteur ; Hongye Su, Auteur ; Weifeng Hou, Auteur Année de publication : 2012 Article en page(s) : pp. 6085–6098 Note générale : Industrial chemistry Langues : Anglais (eng) Mots-clés : Hydrogenation process Résumé : In a refinery, hydrogen, as a valuable resource, is also a byproduct and a significant raw material source of the petroleum refining and petrochemical hydrogenation process. To reduce costs and save energy for the petrochemical industry, the hydrogen system in a refinery should be operated under the optimal scheme to meet the varying hydrogen demands of hydrogen consumers. Optimal scheduling of the hydrogen system can help a refinery to achieve cost reduction and cleaner production. In this paper, a discrete-time mixed-integer nonlinear programming (MINLP) model that considers the penalties for abnormal situations in the hydrogen pipe network (HPN), compressors start–stop, and changes in hydrogen sources for hydrogen consumers is proposed for the optimal scheduling of the hydrogen system under multiperiod operation. The solution of the scheduling problem is obtained based on an iterative method between that of a mixed-integer linear programming (MILP) problem and that of a nonlinear programming (NLP) problem, avoiding the solution of the MINLP problem directly and the occurrence of composition discrepancy. A case study based on the data from a real refinery is presented to illustrate the effectiveness and feasibility of the proposed methodology. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie2019239
in Industrial & engineering chemistry research > Vol. 51 N° 17 (Mai 2012) . - pp. 6085–6098[article] A Multiperiod optimization model for hydrogen system scheduling in refinery [texte imprimé] / Yunqiang Jiao, Auteur ; Hongye Su, Auteur ; Weifeng Hou, Auteur . - 2012 . - pp. 6085–6098.
Industrial chemistry
Langues : Anglais (eng)
in Industrial & engineering chemistry research > Vol. 51 N° 17 (Mai 2012) . - pp. 6085–6098
Mots-clés : Hydrogenation process Résumé : In a refinery, hydrogen, as a valuable resource, is also a byproduct and a significant raw material source of the petroleum refining and petrochemical hydrogenation process. To reduce costs and save energy for the petrochemical industry, the hydrogen system in a refinery should be operated under the optimal scheme to meet the varying hydrogen demands of hydrogen consumers. Optimal scheduling of the hydrogen system can help a refinery to achieve cost reduction and cleaner production. In this paper, a discrete-time mixed-integer nonlinear programming (MINLP) model that considers the penalties for abnormal situations in the hydrogen pipe network (HPN), compressors start–stop, and changes in hydrogen sources for hydrogen consumers is proposed for the optimal scheduling of the hydrogen system under multiperiod operation. The solution of the scheduling problem is obtained based on an iterative method between that of a mixed-integer linear programming (MILP) problem and that of a nonlinear programming (NLP) problem, avoiding the solution of the MINLP problem directly and the occurrence of composition discrepancy. A case study based on the data from a real refinery is presented to illustrate the effectiveness and feasibility of the proposed methodology. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie2019239 Exemplaires
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Titre : Bench-Scale Operation of a Concrete Sludge Recycling Plant Type de document : texte imprimé Auteurs : Atsushi Iizuka, Auteur ; Yuka Sakai, Auteur ; Akihiro Yamasaki, Auteur Année de publication : 2012 Article en page(s) : pp. 6099–6104 Note générale : Industrial chemistry Langues : Anglais (eng) Mots-clés : Concrete sludge recycling Résumé : A bench-scale plant for waste concrete sludge recycling was designed, constructed, and operated. Real concrete sludge generated from a pile and pole production plant and groundwater were used for the experiments. The process mainly consists of the extraction of calcium ions from the concrete sludge into the aqueous phase and the crystallization of calcium carbonate from the solution with CO2. The CO2 was supplied from boilers installed in the plant, where heavy oil is combusted. High-purity calcium carbonate (>99%) was obtained in the process, with particle sizes distributed in the range of 3–30 μm (volume-based), peaking at about 10 μm. A net reduction in CO2 emissions can be achieved based on the process power consumption and the amount of product. The effects of operating conditions on process performance data such as calcium extraction rate and calcium carbonate crystallization rate were examined, which can lead to scaling-up of the plant. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie300620u
in Industrial & engineering chemistry research > Vol. 51 N° 17 (Mai 2012) . - pp. 6099–6104[article] Bench-Scale Operation of a Concrete Sludge Recycling Plant [texte imprimé] / Atsushi Iizuka, Auteur ; Yuka Sakai, Auteur ; Akihiro Yamasaki, Auteur . - 2012 . - pp. 6099–6104.
Industrial chemistry
Langues : Anglais (eng)
in Industrial & engineering chemistry research > Vol. 51 N° 17 (Mai 2012) . - pp. 6099–6104
Mots-clés : Concrete sludge recycling Résumé : A bench-scale plant for waste concrete sludge recycling was designed, constructed, and operated. Real concrete sludge generated from a pile and pole production plant and groundwater were used for the experiments. The process mainly consists of the extraction of calcium ions from the concrete sludge into the aqueous phase and the crystallization of calcium carbonate from the solution with CO2. The CO2 was supplied from boilers installed in the plant, where heavy oil is combusted. High-purity calcium carbonate (>99%) was obtained in the process, with particle sizes distributed in the range of 3–30 μm (volume-based), peaking at about 10 μm. A net reduction in CO2 emissions can be achieved based on the process power consumption and the amount of product. The effects of operating conditions on process performance data such as calcium extraction rate and calcium carbonate crystallization rate were examined, which can lead to scaling-up of the plant. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie300620u Exemplaires
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Titre : Mean - squared - error methods for selecting optimal parameter subsets for estimation Type de document : texte imprimé Auteurs : Kevin A. P. McLean, Auteur ; Shaohua Wu, Auteur ; Kimberley B. McAuley, Auteur Année de publication : 2012 Article en page(s) : pp. 6105–6115 Note générale : Industrial chemistry Langues : Anglais (eng) Mots-clés : Chemical processes Optimal parameter Estimation Résumé : Engineers who develop fundamental models for chemical processes are often unable to estimate all of the parameters, especially when available data are limited or noisy. In these situations, modelers may decide to select only a subset of the parameters for estimation. An orthogonalization algorithm combined with a mean squared error (MSE) based selection criterion has been used to rank parameters from most to least estimable and to determine the parameter subset that should be estimated to obtain the best predictions. A robustness test is proposed and applied to a batch reactor model to assess the sensitivity of the selected parameter subset to initial parameter guesses. A new ranking and selection technique is also developed based on the MSE criterion and is compared with existing techniques in the literature. Results obtained using the proposed ranking and selection techniques agree with those from leave-one-out cross-validation but are more computationally attractive. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie202352f
in Industrial & engineering chemistry research > Vol. 51 N° 17 (Mai 2012) . - pp. 6105–6115[article] Mean - squared - error methods for selecting optimal parameter subsets for estimation [texte imprimé] / Kevin A. P. McLean, Auteur ; Shaohua Wu, Auteur ; Kimberley B. McAuley, Auteur . - 2012 . - pp. 6105–6115.
Industrial chemistry
Langues : Anglais (eng)
in Industrial & engineering chemistry research > Vol. 51 N° 17 (Mai 2012) . - pp. 6105–6115
Mots-clés : Chemical processes Optimal parameter Estimation Résumé : Engineers who develop fundamental models for chemical processes are often unable to estimate all of the parameters, especially when available data are limited or noisy. In these situations, modelers may decide to select only a subset of the parameters for estimation. An orthogonalization algorithm combined with a mean squared error (MSE) based selection criterion has been used to rank parameters from most to least estimable and to determine the parameter subset that should be estimated to obtain the best predictions. A robustness test is proposed and applied to a batch reactor model to assess the sensitivity of the selected parameter subset to initial parameter guesses. A new ranking and selection technique is also developed based on the MSE criterion and is compared with existing techniques in the literature. Results obtained using the proposed ranking and selection techniques agree with those from leave-one-out cross-validation but are more computationally attractive. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie202352f Exemplaires
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Titre : Pareto Approach in Designing Optimal Semicontinuous Water Networks Type de document : texte imprimé Auteurs : Elena-Lacramioara Dogaru, Auteur ; Vasile Lavric, Auteur Année de publication : 2012 Article en page(s) : pp. 6116–6136 Note générale : Industrial chemistry Langues : Anglais (eng) Mots-clés : Pareto optimization Semicontinuous water networks Résumé : Pareto optimization approach was used in searching for the particular successions of topologies and operating conditions for a semicontinuous water network (batch with respect to the raw materials) that minimize both the freshwater consumption and the investment and operating costs. The semicontinuous wastewater network (SWN) formed of N water-using units (WUs), each handling at most K contaminants, and one storage tank (ST) is optimized on time intervals by increasing the wastewater reuse opportunities. A single freshwater source is available and later a regeneration unit (RU) is added to the network as a fine-tuning tool in the Pareto optimization, and further its influence is discussed. The WUs are ordered simultaneously by schedule and by maximum allowable outlet concentrations of contaminants. Thus, the rules concerning the internal reuse between the overlapping WUs correspond to an oriented graph: no recycle is allowed against the ordered sequence. The differential-algebraic equations model consisting in a set of differential equations for the ST and a nonlinear system mass balance equations with restrictions for the overlapping WUs is optimized using the Matlab built in functions for both the genetic algorithms (GA) and the RK-type integrator. The topology of the SWN changes for each time interval, its optimal structure depending upon the minimum freshwater consumption and the costs. A complex synthetic case study was subjected to optimization, and several scenarios are analyzed. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie2024728
in Industrial & engineering chemistry research > Vol. 51 N° 17 (Mai 2012) . - pp. 6116–6136[article] Pareto Approach in Designing Optimal Semicontinuous Water Networks [texte imprimé] / Elena-Lacramioara Dogaru, Auteur ; Vasile Lavric, Auteur . - 2012 . - pp. 6116–6136.
Industrial chemistry
Langues : Anglais (eng)
in Industrial & engineering chemistry research > Vol. 51 N° 17 (Mai 2012) . - pp. 6116–6136
Mots-clés : Pareto optimization Semicontinuous water networks Résumé : Pareto optimization approach was used in searching for the particular successions of topologies and operating conditions for a semicontinuous water network (batch with respect to the raw materials) that minimize both the freshwater consumption and the investment and operating costs. The semicontinuous wastewater network (SWN) formed of N water-using units (WUs), each handling at most K contaminants, and one storage tank (ST) is optimized on time intervals by increasing the wastewater reuse opportunities. A single freshwater source is available and later a regeneration unit (RU) is added to the network as a fine-tuning tool in the Pareto optimization, and further its influence is discussed. The WUs are ordered simultaneously by schedule and by maximum allowable outlet concentrations of contaminants. Thus, the rules concerning the internal reuse between the overlapping WUs correspond to an oriented graph: no recycle is allowed against the ordered sequence. The differential-algebraic equations model consisting in a set of differential equations for the ST and a nonlinear system mass balance equations with restrictions for the overlapping WUs is optimized using the Matlab built in functions for both the genetic algorithms (GA) and the RK-type integrator. The topology of the SWN changes for each time interval, its optimal structure depending upon the minimum freshwater consumption and the costs. A complex synthetic case study was subjected to optimization, and several scenarios are analyzed. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie2024728 Exemplaires
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Titre : A max – min control problem arising in gradient elution chromatography Type de document : texte imprimé Auteurs : Qinqin Chai, Auteur ; Ryan Loxton, Auteur ; Kok Lay Teo, Auteur Année de publication : 2012 Article en page(s) : pp. 6137–6144 Note générale : Industrial chemistry Langues : Anglais (eng) Mots-clés : Chromatography industrial process Résumé : Gradient elution chromatography is an industrial process used to separate and purify multi-component chemical mixtures. In this article, we consider an optimal control problem in which manipulative variables in the chromatographic process need to be determined to maximize separation efficiency. This problem has two nonstandard characteristics: (i) the objective function is nonsmooth, and (ii) each state variable is defined over a different time horizon. The final time for each state variable, the so-called retention time, is not fixed and actually depends on the control variables. To solve this optimal control problem, we first introduce a set of auxiliary decision variables to govern the ordering of the retention times. Then, we approximate the control by a piecewise-constant function and apply a novel time-scaling transformation to map the retention times and control switching times to fixed points in a new time horizon. The retention times and control switching times become decision variables in the new time horizon. On this basis, the optimal control problem is reduced to an approximate nonlinear optimization problem that can be solved using a recently developed exact penalty method. Numerical results show that our approach is both accurate and efficient. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie202475p
in Industrial & engineering chemistry research > Vol. 51 N° 17 (Mai 2012) . - pp. 6137–6144[article] A max – min control problem arising in gradient elution chromatography [texte imprimé] / Qinqin Chai, Auteur ; Ryan Loxton, Auteur ; Kok Lay Teo, Auteur . - 2012 . - pp. 6137–6144.
Industrial chemistry
Langues : Anglais (eng)
in Industrial & engineering chemistry research > Vol. 51 N° 17 (Mai 2012) . - pp. 6137–6144
Mots-clés : Chromatography industrial process Résumé : Gradient elution chromatography is an industrial process used to separate and purify multi-component chemical mixtures. In this article, we consider an optimal control problem in which manipulative variables in the chromatographic process need to be determined to maximize separation efficiency. This problem has two nonstandard characteristics: (i) the objective function is nonsmooth, and (ii) each state variable is defined over a different time horizon. The final time for each state variable, the so-called retention time, is not fixed and actually depends on the control variables. To solve this optimal control problem, we first introduce a set of auxiliary decision variables to govern the ordering of the retention times. Then, we approximate the control by a piecewise-constant function and apply a novel time-scaling transformation to map the retention times and control switching times to fixed points in a new time horizon. The retention times and control switching times become decision variables in the new time horizon. On this basis, the optimal control problem is reduced to an approximate nonlinear optimization problem that can be solved using a recently developed exact penalty method. Numerical results show that our approach is both accurate and efficient. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie202475p Exemplaires
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Titre : Detailed Scheduling of Single-Source Pipelines with Simultaneous Deliveries to Multiple Offtake Stations Type de document : texte imprimé Année de publication : 2012 Langues : Anglais (eng) Mots-clés : Scheduling Pipelines ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie202520a
in Industrial & engineering chemistry research > Vol. 51 N° 17 (Mai 2012)[article] Detailed Scheduling of Single-Source Pipelines with Simultaneous Deliveries to Multiple Offtake Stations [texte imprimé] . - 2012.
Langues : Anglais (eng)
in Industrial & engineering chemistry research > Vol. 51 N° 17 (Mai 2012)
Mots-clés : Scheduling Pipelines ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie202520a Exemplaires
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Titre : Modeling a paper - making wastewater treatment process by means of an adaptive network - based fuzzy inference system and principal component analysis Type de document : texte imprimé Auteurs : Mingzhi Huang, Auteur ; Yongwen Ma, Auteur ; Jinquan Wan, Auteur Année de publication : 2012 Article en page(s) : pp. 6166–6174 Note générale : Industrial chemistry Langues : Anglais (eng) Mots-clés : Paper making wastewater treatment process Résumé : In this paper, a predictive control system based on an adaptive network-based fuzzy inference system (ANFIS) was employed to develop models for predicting and controlling the performance of a paper-making wastewater treatment process. The system includes an ANFIS predictive model and an ANFIS controller. In order to improve the network performance, fuzzy subtractive clustering, euclidean distance clustering, and principal component analysis (PCA) were used to identify model architecture and extract and optimize the fuzzy rule of the model. For the developed predictive model, when predicting, mean absolute percentage error (MAPE) lay 6.06% adopting ANFIS, root mean square normalized error (RMSE) was 24.4485 and R was 0.9731. The control model, taking into account the difference between the predicted value of chemical oxygen demand (COD) and the set point, can effectively change the additive dosages. In order to verify the developed predictive control model, a paper-making wastewater treatment process was picked up to support the operational performance. When the influent COD value or inflow flow rate was changed, the dosage could be accurately adjusted to make the effluent COD remain at the set point, and its MAPE was only 5.19%. The results indicated that reasonable forecasting and controlling performances had been achieved through the developed system. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie203049r
in Industrial & engineering chemistry research > Vol. 51 N° 17 (Mai 2012) . - pp. 6166–6174[article] Modeling a paper - making wastewater treatment process by means of an adaptive network - based fuzzy inference system and principal component analysis [texte imprimé] / Mingzhi Huang, Auteur ; Yongwen Ma, Auteur ; Jinquan Wan, Auteur . - 2012 . - pp. 6166–6174.
Industrial chemistry
Langues : Anglais (eng)
in Industrial & engineering chemistry research > Vol. 51 N° 17 (Mai 2012) . - pp. 6166–6174
Mots-clés : Paper making wastewater treatment process Résumé : In this paper, a predictive control system based on an adaptive network-based fuzzy inference system (ANFIS) was employed to develop models for predicting and controlling the performance of a paper-making wastewater treatment process. The system includes an ANFIS predictive model and an ANFIS controller. In order to improve the network performance, fuzzy subtractive clustering, euclidean distance clustering, and principal component analysis (PCA) were used to identify model architecture and extract and optimize the fuzzy rule of the model. For the developed predictive model, when predicting, mean absolute percentage error (MAPE) lay 6.06% adopting ANFIS, root mean square normalized error (RMSE) was 24.4485 and R was 0.9731. The control model, taking into account the difference between the predicted value of chemical oxygen demand (COD) and the set point, can effectively change the additive dosages. In order to verify the developed predictive control model, a paper-making wastewater treatment process was picked up to support the operational performance. When the influent COD value or inflow flow rate was changed, the dosage could be accurately adjusted to make the effluent COD remain at the set point, and its MAPE was only 5.19%. The results indicated that reasonable forecasting and controlling performances had been achieved through the developed system. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie203049r Exemplaires
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Titre : Investigation of the effect of slurry density on a bitumen separation process based on cavitating jets Type de document : texte imprimé Auteurs : Nikolay S. Bukharin, Auteur ; Oleg G. Vinogradov, Auteur Année de publication : 2012 Article en page(s) : pp. 6175–6183 Note générale : Industrial chemistry Langues : Anglais (eng) Mots-clés : Bitumen separation process Cavitating jets Résumé : The effect of slurry density on a bitumen separation process based on a new cavitating jet technology at low temperatures is investigated. The experiments were conducted in a custom-made apparatus. It is shown that the cavitation effect does take place at increased slurry densities, and thus its application in industry will lead to increased efficiency of bitumen extraction. A comparison of the results for cavitating and noncavitating jets is provided to validate the effect of cavitation. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie202382j
in Industrial & engineering chemistry research > Vol. 51 N° 17 (Mai 2012) . - pp. 6175–6183[article] Investigation of the effect of slurry density on a bitumen separation process based on cavitating jets [texte imprimé] / Nikolay S. Bukharin, Auteur ; Oleg G. Vinogradov, Auteur . - 2012 . - pp. 6175–6183.
Industrial chemistry
Langues : Anglais (eng)
in Industrial & engineering chemistry research > Vol. 51 N° 17 (Mai 2012) . - pp. 6175–6183
Mots-clés : Bitumen separation process Cavitating jets Résumé : The effect of slurry density on a bitumen separation process based on a new cavitating jet technology at low temperatures is investigated. The experiments were conducted in a custom-made apparatus. It is shown that the cavitation effect does take place at increased slurry densities, and thus its application in industry will lead to increased efficiency of bitumen extraction. A comparison of the results for cavitating and noncavitating jets is provided to validate the effect of cavitation. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie202382j Exemplaires
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Titre : Treatment of pulp and paper mill wastewater using utrafiltration process : Optimization of the fouling and rejections Type de document : texte imprimé Auteurs : Z. Beril Gonder, Auteur ; Semiha Arayici, Auteur ; Hulusi Barlas, Auteur Année de publication : 2012 Article en page(s) : pp. 6184–6195 Note générale : Industrial chemistry Langues : Anglais (eng) Mots-clés : Treatment pulp wastewater Résumé : Treatment of pulp and paper mill wastewater using ultrafiltration (UF) membranes was investigated in this study. A Taguchi experimental design was implemented for design of the experiments to investigate optimum operating conditions that achieve higher removal of pollutants and lower membrane fouling. Four factors at three different levels were considered for the experimental design, namely, pH, temperature, transmembrane pressure, and volume reduction factor (VRF). Under the optimized conditions (pH 10, temperature 25 °C, transmembrane pressure 6 bar, and VRF 3), a 35% flux decline caused by fouling occurred. Higher rejections were observed for total hardness (83%), sulfate (97%), spectral absorption coefficient (SAC254) (95%), and chemical oxygen demand (COD) (89%), but not for conductivity (50%), under these conditions. From the analysis of variance (ANOVA), it was determined that the factor of pH made the greatest contribution to response parameters. Atomic force microscopy (AFM) and scanning electron microscopy (SEM) analyses showed that membrane fouling occurring on the membrane surface and within pores decreased by optimizing the operating conditions. The Taguchi method was successfully applied to find the optimum conditions for the treatment of pulp and paper mill wastewater using the UF process. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie2024504
in Industrial & engineering chemistry research > Vol. 51 N° 17 (Mai 2012) . - pp. 6184–6195[article] Treatment of pulp and paper mill wastewater using utrafiltration process : Optimization of the fouling and rejections [texte imprimé] / Z. Beril Gonder, Auteur ; Semiha Arayici, Auteur ; Hulusi Barlas, Auteur . - 2012 . - pp. 6184–6195.
Industrial chemistry
Langues : Anglais (eng)
in Industrial & engineering chemistry research > Vol. 51 N° 17 (Mai 2012) . - pp. 6184–6195
Mots-clés : Treatment pulp wastewater Résumé : Treatment of pulp and paper mill wastewater using ultrafiltration (UF) membranes was investigated in this study. A Taguchi experimental design was implemented for design of the experiments to investigate optimum operating conditions that achieve higher removal of pollutants and lower membrane fouling. Four factors at three different levels were considered for the experimental design, namely, pH, temperature, transmembrane pressure, and volume reduction factor (VRF). Under the optimized conditions (pH 10, temperature 25 °C, transmembrane pressure 6 bar, and VRF 3), a 35% flux decline caused by fouling occurred. Higher rejections were observed for total hardness (83%), sulfate (97%), spectral absorption coefficient (SAC254) (95%), and chemical oxygen demand (COD) (89%), but not for conductivity (50%), under these conditions. From the analysis of variance (ANOVA), it was determined that the factor of pH made the greatest contribution to response parameters. Atomic force microscopy (AFM) and scanning electron microscopy (SEM) analyses showed that membrane fouling occurring on the membrane surface and within pores decreased by optimizing the operating conditions. The Taguchi method was successfully applied to find the optimum conditions for the treatment of pulp and paper mill wastewater using the UF process. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie2024504 Exemplaires
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Titre : Adsorption property of cesium onto modified macroporous silica – calix [4] arene - crown based supramolecular recognition materials Type de document : texte imprimé Auteurs : Anyun Zhang, Auteur ; Zhifang Chai, Auteur Année de publication : 2012 Article en page(s) : pp. 6196-6204 Note générale : Industrial chemistry Langues : Anglais (eng) Mots-clés : Macroporosity Adsorption Résumé : The adsorption behavior of Cs(I), one of the heat generators, in HNO3 medium was investigated at 298 K. The impact of U(VI), some typical elements, and temperature on the adsorption of Cs(I) was evaluated. It was performed by macroporous silica-based 1,3-[(2,4-diethylheptylethoxy)oxy]-2,4-crown-6-calix[4]arene (Calix[4]arene-R14) impregnated supramolecular recognition materials (Calix[4] + M)/SiO2–P. They were modified with tri-n-butyl phosphate (TBP), octanol (Oct), and methyloctyl-2-dimethylbutanemide (MODB). The excellent adsorption ability and high selectivity of (Calix[4] + M)/SiO2–P for Cs(I) except Rb(I) and U(VI) were confirmed. The adsorption ability of Cs(I) onto the modified supramolecular recognition materials was (Calix[4] + Oct)/SiO2–P > (Calix[4] + TBP)/SiO2–P > (Calix[4] + MODB)/SiO2–P. The chromatographic separation of Cs(I) from a 4.0 M HNO3 solution containing La(III), Sr(II), Ru(III), Cs(I), Rb(I), U(VI), Mo(VI), Zr(IV), Gd(III), and Pd(II) was carried out with a (Calix[4] + TBP)/SiO2–P packed column. Cs(I) was eluted effectively with water. The possibility and feasibility of effective partitioning of Cs(I) from highly active liquid waste by the (Calix[4] + M)/SiO2–P materials was evaluated. ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=25862979
in Industrial & engineering chemistry research > Vol. 51 N° 17 (Mai 2012) . - pp. 6196-6204[article] Adsorption property of cesium onto modified macroporous silica – calix [4] arene - crown based supramolecular recognition materials [texte imprimé] / Anyun Zhang, Auteur ; Zhifang Chai, Auteur . - 2012 . - pp. 6196-6204.
Industrial chemistry
Langues : Anglais (eng)
in Industrial & engineering chemistry research > Vol. 51 N° 17 (Mai 2012) . - pp. 6196-6204
Mots-clés : Macroporosity Adsorption Résumé : The adsorption behavior of Cs(I), one of the heat generators, in HNO3 medium was investigated at 298 K. The impact of U(VI), some typical elements, and temperature on the adsorption of Cs(I) was evaluated. It was performed by macroporous silica-based 1,3-[(2,4-diethylheptylethoxy)oxy]-2,4-crown-6-calix[4]arene (Calix[4]arene-R14) impregnated supramolecular recognition materials (Calix[4] + M)/SiO2–P. They were modified with tri-n-butyl phosphate (TBP), octanol (Oct), and methyloctyl-2-dimethylbutanemide (MODB). The excellent adsorption ability and high selectivity of (Calix[4] + M)/SiO2–P for Cs(I) except Rb(I) and U(VI) were confirmed. The adsorption ability of Cs(I) onto the modified supramolecular recognition materials was (Calix[4] + Oct)/SiO2–P > (Calix[4] + TBP)/SiO2–P > (Calix[4] + MODB)/SiO2–P. The chromatographic separation of Cs(I) from a 4.0 M HNO3 solution containing La(III), Sr(II), Ru(III), Cs(I), Rb(I), U(VI), Mo(VI), Zr(IV), Gd(III), and Pd(II) was carried out with a (Calix[4] + TBP)/SiO2–P packed column. Cs(I) was eluted effectively with water. The possibility and feasibility of effective partitioning of Cs(I) from highly active liquid waste by the (Calix[4] + M)/SiO2–P materials was evaluated. ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=25862979 Exemplaires
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Titre : Recovery of hydrogen from coke - oven gas by forming hydrate Type de document : texte imprimé Auteurs : Qiang Sun, Auteur ; Jiangjie Dong, Auteur ; Xuqiang Guo, Auteur Année de publication : 2012 Article en page(s) : pp. 6205-6211 Note générale : Industrial chemistry Langues : Anglais (eng) Mots-clés : Coke oven gas Résumé : Coke-oven gas (COG), a byproduct of the coking process, has a relatively large fraction of hydrogen (H2). However, most COG is combusted away directly, resulting in serious waste of resources. Taking advantage of a separation gas mixture containing H2, we used a hydrate separation method in this work to recover H2 from COG. The formation conditions of COG hydrate were measured in 6 mol % tetrahydrofuran (THF) solution, which could significantly reduce COG hydrate formation pressures and make it possible to realize the industrial application of the separation technology. On this basis, the separation experiments were conducted in THF solution and THF-sodium dodecyl sulfate (SDS) solution, respectively. The experimental results of two-stage separation of COG via hydrate formation were obtained, and the effects of SDS on the reaction velocity were investigated as well. The results show that after one-stage separation, the content of H2 in residual gas can be increased from 48.41 mol % to about 65 mol %, and the recovery of H2 ranges from 81% to 96%. After two-stage separation, the content of H2 in residual gas ranges from 76 mol % to 84 mol %, and the recovery of H2 is between 72% and 91%. With the presence of SDS, the hydration reaction velocity is sped up to some extent, and the induction time and reaction time of hydrate formation are greatly shortened. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie203041n
in Industrial & engineering chemistry research > Vol. 51 N° 17 (Mai 2012) . - pp. 6205-6211[article] Recovery of hydrogen from coke - oven gas by forming hydrate [texte imprimé] / Qiang Sun, Auteur ; Jiangjie Dong, Auteur ; Xuqiang Guo, Auteur . - 2012 . - pp. 6205-6211.
Industrial chemistry
Langues : Anglais (eng)
in Industrial & engineering chemistry research > Vol. 51 N° 17 (Mai 2012) . - pp. 6205-6211
Mots-clés : Coke oven gas Résumé : Coke-oven gas (COG), a byproduct of the coking process, has a relatively large fraction of hydrogen (H2). However, most COG is combusted away directly, resulting in serious waste of resources. Taking advantage of a separation gas mixture containing H2, we used a hydrate separation method in this work to recover H2 from COG. The formation conditions of COG hydrate were measured in 6 mol % tetrahydrofuran (THF) solution, which could significantly reduce COG hydrate formation pressures and make it possible to realize the industrial application of the separation technology. On this basis, the separation experiments were conducted in THF solution and THF-sodium dodecyl sulfate (SDS) solution, respectively. The experimental results of two-stage separation of COG via hydrate formation were obtained, and the effects of SDS on the reaction velocity were investigated as well. The results show that after one-stage separation, the content of H2 in residual gas can be increased from 48.41 mol % to about 65 mol %, and the recovery of H2 ranges from 81% to 96%. After two-stage separation, the content of H2 in residual gas ranges from 76 mol % to 84 mol %, and the recovery of H2 is between 72% and 91%. With the presence of SDS, the hydration reaction velocity is sped up to some extent, and the induction time and reaction time of hydrate formation are greatly shortened. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie203041n Exemplaires
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Titre : Microbial transformation of structural and functional makeup of human - impacted riverine dissolved organic matter Type de document : texte imprimé Auteurs : Fangang Meng, Auteur ; Guocheng Huang, Auteur ; Zengquan Li, Auteur Année de publication : 2012 Article en page(s) : pp. 6212-6218 Note générale : Industrial chemistry Langues : Anglais (eng) Mots-clés : Organic matter Human Résumé : The aim of this study was to reveal the biotransformation of human-impacted riverine dissolved organic matter (DOM) using well-controlled bioassay tests, with a focus on the biodegradation of the structural and functional makeup. Results of three-dimensional fluorescence excitation-emission matrix with parallel factor analysis (EEM-PARAFAC) showed that humic substances derived from human activities (i.e., anthropogenic humic-like substances) were of higher biodegradation potentials than terrestrial and microbial humic-like substances. In addition, the biodegradation finally led to an increase of the percentage contribution of fluorescent DOM to the total DOM. Characterization by nuclear magnetic resonance (NMR) spectroscopy indicated that large amounts of the structural components of the DOM were removed within 3 h of biodegradation. Characterization by X-ray photoelectron spectroscopy (XPS) further revealed that the riverine DOM contained various functional groups that underwent different biotransformation mechanisms. The XPS data also indicated the appearance of newly generated, oxygen-rich functional groups upon biodegradation and the disappearance of nitrogen-containing groups as a result of hydrolysis and nitrification of organic and/or ammonium nitrogen. ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=25862981
in Industrial & engineering chemistry research > Vol. 51 N° 17 (Mai 2012) . - pp. 6212-6218[article] Microbial transformation of structural and functional makeup of human - impacted riverine dissolved organic matter [texte imprimé] / Fangang Meng, Auteur ; Guocheng Huang, Auteur ; Zengquan Li, Auteur . - 2012 . - pp. 6212-6218.
Industrial chemistry
Langues : Anglais (eng)
in Industrial & engineering chemistry research > Vol. 51 N° 17 (Mai 2012) . - pp. 6212-6218
Mots-clés : Organic matter Human Résumé : The aim of this study was to reveal the biotransformation of human-impacted riverine dissolved organic matter (DOM) using well-controlled bioassay tests, with a focus on the biodegradation of the structural and functional makeup. Results of three-dimensional fluorescence excitation-emission matrix with parallel factor analysis (EEM-PARAFAC) showed that humic substances derived from human activities (i.e., anthropogenic humic-like substances) were of higher biodegradation potentials than terrestrial and microbial humic-like substances. In addition, the biodegradation finally led to an increase of the percentage contribution of fluorescent DOM to the total DOM. Characterization by nuclear magnetic resonance (NMR) spectroscopy indicated that large amounts of the structural components of the DOM were removed within 3 h of biodegradation. Characterization by X-ray photoelectron spectroscopy (XPS) further revealed that the riverine DOM contained various functional groups that underwent different biotransformation mechanisms. The XPS data also indicated the appearance of newly generated, oxygen-rich functional groups upon biodegradation and the disappearance of nitrogen-containing groups as a result of hydrolysis and nitrification of organic and/or ammonium nitrogen. ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=25862981 Exemplaires
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Titre : Optimization of transferable site – site potentials using a combination of stochastic and gradient search algorithms Type de document : texte imprimé Auteurs : Sinan Ucyigitler, Auteur ; Mehmet C. Camurdan, Auteur ; J. Richard Elliott, Auteur Année de publication : 2012 Article en page(s) : pp. 6219–6231 Note générale : Industrial chemistry Langues : Anglais (eng) Mots-clés : Optimization Stochastic Algorithms Résumé : Discontinuous molecular dynamics (DMD) simulation and thermodynamic perturbation theory (TPT) have been used to study thermodynamic properties for organic compounds. The aim is to infer transferable intermolecular potential models based on correlating the vapor pressure and liquid density. The combination of DMD/TPT generates a straightforward global optimization problem for the attractive potential, instead of facing an iterative optimization–simulation type problem. This global optimization problem is then formulated as a black-box optimization problem and solved using a combination of random recursive search (RRS) and Levenberg–Marquardt (LM) optimization. RRS is suitable for black-box optimization problems since its algorithm is robust to the effect of random noises in the objective function and is advantageous in optimizing the objective function with negligible parameters. LM is efficient local to an optimum with a smooth response surface. The local response surface is shown to be smooth but very flat along valleys with a high degree of coupling between the potential parameters. The algorithm is demonstrated with discretized versions of the Lennard-Jones (LJ) potential and a linear step potential using a database of 231 hydrocarbons, alcohols, aldehydes, amines, amides, esters, ethers, ketones, phenols, sulfides, and thiols. A correspondence is established between the discretized LJ potential and the TraPPE model, demonstrating the manner of improving density estimates and a way of expediting improvement of continuous transferable potentials. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie201186q
in Industrial & engineering chemistry research > Vol. 51 N° 17 (Mai 2012) . - pp. 6219–6231[article] Optimization of transferable site – site potentials using a combination of stochastic and gradient search algorithms [texte imprimé] / Sinan Ucyigitler, Auteur ; Mehmet C. Camurdan, Auteur ; J. Richard Elliott, Auteur . - 2012 . - pp. 6219–6231.
Industrial chemistry
Langues : Anglais (eng)
in Industrial & engineering chemistry research > Vol. 51 N° 17 (Mai 2012) . - pp. 6219–6231
Mots-clés : Optimization Stochastic Algorithms Résumé : Discontinuous molecular dynamics (DMD) simulation and thermodynamic perturbation theory (TPT) have been used to study thermodynamic properties for organic compounds. The aim is to infer transferable intermolecular potential models based on correlating the vapor pressure and liquid density. The combination of DMD/TPT generates a straightforward global optimization problem for the attractive potential, instead of facing an iterative optimization–simulation type problem. This global optimization problem is then formulated as a black-box optimization problem and solved using a combination of random recursive search (RRS) and Levenberg–Marquardt (LM) optimization. RRS is suitable for black-box optimization problems since its algorithm is robust to the effect of random noises in the objective function and is advantageous in optimizing the objective function with negligible parameters. LM is efficient local to an optimum with a smooth response surface. The local response surface is shown to be smooth but very flat along valleys with a high degree of coupling between the potential parameters. The algorithm is demonstrated with discretized versions of the Lennard-Jones (LJ) potential and a linear step potential using a database of 231 hydrocarbons, alcohols, aldehydes, amines, amides, esters, ethers, ketones, phenols, sulfides, and thiols. A correspondence is established between the discretized LJ potential and the TraPPE model, demonstrating the manner of improving density estimates and a way of expediting improvement of continuous transferable potentials. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie201186q Exemplaires
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Titre : Phase equilibria of CO2 + n - alkane binary systems in wide ranges of conditions : Development of predictive correlations based on cubic mixing rules Type de document : texte imprimé Auteurs : Martín Cismondi, Auteur ; Sabrina B. Rodriguez-Reartes, Auteur ; Juan M. Milanesio, Auteur Année de publication : 2012 Article en page(s) : pp. 6232-6250 Note générale : Industrial chemistry Langues : Anglais (eng) Mots-clés : Thermodynamic properties Mixing rule Correlation analysis Binary system Carbon dioxide Phase equilibrium Résumé : The phase equilibria of binary CO2 + n-alkane mixtures have been studied by an important number of authors, both experimentally and using different types of thermodynamic models. Modeling studies of the phase behavior of such highly nonideal systems have generally achieved only partially accurate results in the correlation of phase equilibrium data when considering wide ranges of temperature, pressure, and n-alkane molecular weight. In this study, a predictive correlation for the phase behavior of CO2 + n-alkane systems, based on a three-parameter cubic equation of state (EOS), that is, the RK-PR EOS, coupled to cubic mixing rules (CMRs), is developed and tested. CMRs have been shown to be capable of an accurate correlation of the phase equilibria asymmetric CO2 + n-alkane binary systems, in wide ranges of temperature and pressure, when using system-specific interaction parameters. For developing the predictive correlation a critical review of published experimental data for the series was carried out, covering a total of about 100 references. An important degree of inaccuracy or scatter is often found when comparing data sets from different laboratories, specially for the more asymmetric systems (CO2 + a long chain n-alkane). Tables of references covering CO2 + n-alkane systems from C1 to C36 are presented for different types of experimental data, including critical end points (CEPs), critical points, liquid-liquid-vapor (LLV) equilibrium, and isobaric (Txy), isothermal (Pxy), and isoplethic (PT) two-phase equilibrium data sets. Examples of disagreement between different sets of data are presented and discussed. In some cases, a decision concerning the identification of the set that should be regarded as the most reliable, can be based on the experimental method employed, on the purity of the n-alkane, and on the observation of other data for conditions, and/or systems in the series, which are close to those of the data set under scrutiny. Nevertheless, the availability of such information is not enough, in other cases, to assess the quality of a given data set, where we have either different data sets in disagreement or a unique set, for which we are in doubt about its accuracy. In such situation, a predictive correlation for the whole series of binary systems is helpful to make a decision on the possible level of reliability of a given phase equilibrium data set. The present study is useful both to make decisions on conflicts between contradictory phase equilibrium data sets and to predict the phase equilibria of binary systems that have no experimental information available in the literature. REFERENCE : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=25862983
in Industrial & engineering chemistry research > Vol. 51 N° 17 (Mai 2012) . - pp. 6232-6250[article] Phase equilibria of CO2 + n - alkane binary systems in wide ranges of conditions : Development of predictive correlations based on cubic mixing rules [texte imprimé] / Martín Cismondi, Auteur ; Sabrina B. Rodriguez-Reartes, Auteur ; Juan M. Milanesio, Auteur . - 2012 . - pp. 6232-6250.
Industrial chemistry
Langues : Anglais (eng)
in Industrial & engineering chemistry research > Vol. 51 N° 17 (Mai 2012) . - pp. 6232-6250
Mots-clés : Thermodynamic properties Mixing rule Correlation analysis Binary system Carbon dioxide Phase equilibrium Résumé : The phase equilibria of binary CO2 + n-alkane mixtures have been studied by an important number of authors, both experimentally and using different types of thermodynamic models. Modeling studies of the phase behavior of such highly nonideal systems have generally achieved only partially accurate results in the correlation of phase equilibrium data when considering wide ranges of temperature, pressure, and n-alkane molecular weight. In this study, a predictive correlation for the phase behavior of CO2 + n-alkane systems, based on a three-parameter cubic equation of state (EOS), that is, the RK-PR EOS, coupled to cubic mixing rules (CMRs), is developed and tested. CMRs have been shown to be capable of an accurate correlation of the phase equilibria asymmetric CO2 + n-alkane binary systems, in wide ranges of temperature and pressure, when using system-specific interaction parameters. For developing the predictive correlation a critical review of published experimental data for the series was carried out, covering a total of about 100 references. An important degree of inaccuracy or scatter is often found when comparing data sets from different laboratories, specially for the more asymmetric systems (CO2 + a long chain n-alkane). Tables of references covering CO2 + n-alkane systems from C1 to C36 are presented for different types of experimental data, including critical end points (CEPs), critical points, liquid-liquid-vapor (LLV) equilibrium, and isobaric (Txy), isothermal (Pxy), and isoplethic (PT) two-phase equilibrium data sets. Examples of disagreement between different sets of data are presented and discussed. In some cases, a decision concerning the identification of the set that should be regarded as the most reliable, can be based on the experimental method employed, on the purity of the n-alkane, and on the observation of other data for conditions, and/or systems in the series, which are close to those of the data set under scrutiny. Nevertheless, the availability of such information is not enough, in other cases, to assess the quality of a given data set, where we have either different data sets in disagreement or a unique set, for which we are in doubt about its accuracy. In such situation, a predictive correlation for the whole series of binary systems is helpful to make a decision on the possible level of reliability of a given phase equilibrium data set. The present study is useful both to make decisions on conflicts between contradictory phase equilibrium data sets and to predict the phase equilibria of binary systems that have no experimental information available in the literature. REFERENCE : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=25862983 Exemplaires
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Titre : Quantitative structure - property relationship prediction of liquid heat capacity at 298.15 K for organic compounds Type de document : texte imprimé Auteurs : Aboozar Khajeh, Auteur ; Hamid Modarress, Auteur Année de publication : 2012 Article en page(s) : pp. 6251-6255 Note générale : Industrial chemistry Langues : Anglais (eng) Mots-clés : Heat capacity Prediction Property structure relationship Résumé : Novel QSPR models were developed and evaluated for the prediction of heat capacity of liquids at 298.15 K with only three descriptors. Two linear and nonlinear models were produced using genetic function approximation (GFA) and adaptive neurofuzzy inference system (ANFIS) methods based on a data set of 706 compounds with a wide variety of functional groups. The results showed that both GFA and ANFIS methods could model the relationship between the liquid heat capacity of organic compounds and their structures with high accuracy. The predictive quality of the QSPR models were tested for an external test set, where the squared correlation coefficients of prediction for the GFA and ANFIS methods were 0.970 and 0.973, respectively. ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=25862984
in Industrial & engineering chemistry research > Vol. 51 N° 17 (Mai 2012) . - pp. 6251-6255[article] Quantitative structure - property relationship prediction of liquid heat capacity at 298.15 K for organic compounds [texte imprimé] / Aboozar Khajeh, Auteur ; Hamid Modarress, Auteur . - 2012 . - pp. 6251-6255.
Industrial chemistry
Langues : Anglais (eng)
in Industrial & engineering chemistry research > Vol. 51 N° 17 (Mai 2012) . - pp. 6251-6255
Mots-clés : Heat capacity Prediction Property structure relationship Résumé : Novel QSPR models were developed and evaluated for the prediction of heat capacity of liquids at 298.15 K with only three descriptors. Two linear and nonlinear models were produced using genetic function approximation (GFA) and adaptive neurofuzzy inference system (ANFIS) methods based on a data set of 706 compounds with a wide variety of functional groups. The results showed that both GFA and ANFIS methods could model the relationship between the liquid heat capacity of organic compounds and their structures with high accuracy. The predictive quality of the QSPR models were tested for an external test set, where the squared correlation coefficients of prediction for the GFA and ANFIS methods were 0.970 and 0.973, respectively. ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=25862984 Exemplaires
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Titre : An overview of mutual solubility of ionic liquids and water predicted by COSMO - RS Type de document : texte imprimé Auteurs : Teng Zhou, Auteur ; Long Chen, Auteur ; Yinmei Ye, Auteur Année de publication : 2012 Article en page(s) : pp. 6256-6264 Note générale : Industrial chemistry Langues : Anglais (eng) Mots-clés : Ionic liquid Solubility Résumé : To properly screen and use ionic liquids (ILs) as environmental-friendly solvents in chemical reactors and separation processes, the knowledge of their solubilities with water is essential. In the present work, mutual solubilities of 1500 ILs (50 cations, 30 anions) with water at 298.15 K were predicted by using the conductor-like screening model for real solvents (COSMO-RS) as a thermodynamic model. On the basis of the COSMO-RS calculations, the influence of the types of anion and cation, side chain modifications and substituent groups on the mutual solubility with water was extensively analyzed. The data obtained can be used for the prescreening of ILs as solvent candidates. Moreover, to understand the intrinsic solubility behavior in detail, different types of molecular interactions between ILs and water in solution were compared on the basis of the determination of multiple water-IL interaction energies from COSMO-RS computation. The results confirm that hydrogen bonding interactions between anions and water molecules have the dominant influence on the solubility. Finally, for the purpose of fast solubility estimation and solvent selection, COSMO-RS derived molecular descriptors which indicate the strength of anionic HB acceptors were calculated for typical anions and anion families. ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=25862985
in Industrial & engineering chemistry research > Vol. 51 N° 17 (Mai 2012) . - pp. 6256-6264[article] An overview of mutual solubility of ionic liquids and water predicted by COSMO - RS [texte imprimé] / Teng Zhou, Auteur ; Long Chen, Auteur ; Yinmei Ye, Auteur . - 2012 . - pp. 6256-6264.
Industrial chemistry
Langues : Anglais (eng)
in Industrial & engineering chemistry research > Vol. 51 N° 17 (Mai 2012) . - pp. 6256-6264
Mots-clés : Ionic liquid Solubility Résumé : To properly screen and use ionic liquids (ILs) as environmental-friendly solvents in chemical reactors and separation processes, the knowledge of their solubilities with water is essential. In the present work, mutual solubilities of 1500 ILs (50 cations, 30 anions) with water at 298.15 K were predicted by using the conductor-like screening model for real solvents (COSMO-RS) as a thermodynamic model. On the basis of the COSMO-RS calculations, the influence of the types of anion and cation, side chain modifications and substituent groups on the mutual solubility with water was extensively analyzed. The data obtained can be used for the prescreening of ILs as solvent candidates. Moreover, to understand the intrinsic solubility behavior in detail, different types of molecular interactions between ILs and water in solution were compared on the basis of the determination of multiple water-IL interaction energies from COSMO-RS computation. The results confirm that hydrogen bonding interactions between anions and water molecules have the dominant influence on the solubility. Finally, for the purpose of fast solubility estimation and solvent selection, COSMO-RS derived molecular descriptors which indicate the strength of anionic HB acceptors were calculated for typical anions and anion families. ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=25862985 Exemplaires
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Titre : Corresponding states method for estimation of upper flammability limit temperature of chemical compounds Type de document : texte imprimé Auteurs : Farhad Gharagheizi, Auteur ; Poorandokht Ilani-Kashkouli, Auteur ; Amir H. Mohammadi, Auteur Année de publication : 2012 Article en page(s) : pp. 6265–6269 Note générale : Industrial chemistry Langues : Anglais (eng) Mots-clés : Chemical compounds Flammability limit Résumé : The accuracy and predictability of predictive methods to determine the flammability characteristics of chemical compounds are of drastic significance in the chemical industry. This work aims at continuing application of the gene expression programming (GEP) mathematical strategy to modify the existing thermophysical properties correlations available in the literature to pursue the following objectives: optimization of the number of independent parameters, amplification of the generality, and improvement of the accuracy and predictability. This work deals with presenting a simple corresponding states model to predict the upper flammability limit temperature of 1462 organic compounds from 76 chemical families. The parameters of the correlation include the critical temperature and the acentric factor of the compounds. The obtained statistical parameters including average absolute relative deviation of the results from DIPPR 801 database values (1.7, 1.8, 1.7% for training, optimization, and prediction sets, respectively) demonstrate improved accuracy of the presented correlations. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie300375k
in Industrial & engineering chemistry research > Vol. 51 N° 17 (Mai 2012) . - pp. 6265–6269[article] Corresponding states method for estimation of upper flammability limit temperature of chemical compounds [texte imprimé] / Farhad Gharagheizi, Auteur ; Poorandokht Ilani-Kashkouli, Auteur ; Amir H. Mohammadi, Auteur . - 2012 . - pp. 6265–6269.
Industrial chemistry
Langues : Anglais (eng)
in Industrial & engineering chemistry research > Vol. 51 N° 17 (Mai 2012) . - pp. 6265–6269
Mots-clés : Chemical compounds Flammability limit Résumé : The accuracy and predictability of predictive methods to determine the flammability characteristics of chemical compounds are of drastic significance in the chemical industry. This work aims at continuing application of the gene expression programming (GEP) mathematical strategy to modify the existing thermophysical properties correlations available in the literature to pursue the following objectives: optimization of the number of independent parameters, amplification of the generality, and improvement of the accuracy and predictability. This work deals with presenting a simple corresponding states model to predict the upper flammability limit temperature of 1462 organic compounds from 76 chemical families. The parameters of the correlation include the critical temperature and the acentric factor of the compounds. The obtained statistical parameters including average absolute relative deviation of the results from DIPPR 801 database values (1.7, 1.8, 1.7% for training, optimization, and prediction sets, respectively) demonstrate improved accuracy of the presented correlations. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie300375k Exemplaires
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Titre : Structure and saccharification of rice straw pretreated with microwave - assisted dilute lye Type de document : texte imprimé Auteurs : Feng-he Li, Auteur ; Hua-jia Hu, Auteur ; Ri-sheng Yao, Auteur Année de publication : 2012 Article en page(s) : pp. 6270–6274 Note générale : Industrial chemistry Langues : Anglais (eng) Mots-clés : Microwave Fourier transform infrared spectroscopy Résumé : Surface characteristics of untreated and microwave-assisted dilute lye (MAL) treated rice straw have been investigated using Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), and X-ray diffraction (XRD). Rice straw composition was investigated by lignocelluloses determination. FTIR showed MAL treatment could effectively remove lipophilic extractives from the rice straw surface and break hydrogen bonds in the rice straw, and it was proven that more cellulose was exposed by MAL-treated with SEM. The composition analysis result indicated that the content of cellulose is 46.8% and content of lignin is 8.3% in rice straw with high-fire-power microwave-assisted 1% dilute lye for 1 h, and saccharification rate is 86% with high-fire-power microwave-assisted 1% dilute lye for 2 h. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie202547w
in Industrial & engineering chemistry research > Vol. 51 N° 17 (Mai 2012) . - pp. 6270–6274[article] Structure and saccharification of rice straw pretreated with microwave - assisted dilute lye [texte imprimé] / Feng-he Li, Auteur ; Hua-jia Hu, Auteur ; Ri-sheng Yao, Auteur . - 2012 . - pp. 6270–6274.
Industrial chemistry
Langues : Anglais (eng)
in Industrial & engineering chemistry research > Vol. 51 N° 17 (Mai 2012) . - pp. 6270–6274
Mots-clés : Microwave Fourier transform infrared spectroscopy Résumé : Surface characteristics of untreated and microwave-assisted dilute lye (MAL) treated rice straw have been investigated using Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), and X-ray diffraction (XRD). Rice straw composition was investigated by lignocelluloses determination. FTIR showed MAL treatment could effectively remove lipophilic extractives from the rice straw surface and break hydrogen bonds in the rice straw, and it was proven that more cellulose was exposed by MAL-treated with SEM. The composition analysis result indicated that the content of cellulose is 46.8% and content of lignin is 8.3% in rice straw with high-fire-power microwave-assisted 1% dilute lye for 1 h, and saccharification rate is 86% with high-fire-power microwave-assisted 1% dilute lye for 2 h. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie202547w Exemplaires
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