Nos Abonnements
Ressources Électroniques
|
[n° ou bulletin]
[n° ou bulletin]
Vol. 51 N° 30 - Août 2012 [texte imprimé] . - 2012 . - p. 9919-10286 : ill. ; 28 cm. Chemical engineering Langues : Anglais (eng)
|
Exemplaires
| Code-barres | Cote | Support | Localisation | Section | Disponibilité |
|---|---|---|---|---|---|
| aucun exemplaire | |||||
|
Dépouillements
Ajouter le résultat dans votre panierA Potentially useful technology by mimicking nature — rapid conversion of biomass and CO2 into chemicals and fuels under hydrothermal conditions / Fangming Jin in Industrial & engineering chemistry research, Vol. 51 N° 30 (Août 2012)
Titre : A Potentially useful technology by mimicking nature — rapid conversion of biomass and CO2 into chemicals and fuels under hydrothermal conditions Type de document : texte imprimé Auteurs : Fangming Jin, Auteur ; Xu Zeng, Auteur ; Zhenzi Jing, Auteur Année de publication : 2012 Article en page(s) : pp. 9921-9937 Note générale : Industrial chemistry Langues : Anglais (eng) Mots-clés : Hydrothermal condition Fuel Carbon dioxide Biomass Résumé : To diminish a serious global energy crisis and global warming caused by the imbalance between the slow formation of fossil fuels and rapid consumption by human activities, the developing of the technology for quickly turning biomass and CO2 into fuels and chemicals is needed. Hydrothermal reactions, which can be recognized as an effective pathway in the carbon cycle, played an important role in forming petroleum, natural gas, and coal from organic wastes. If humans could simulate the natural phenomena of the formation of fossils, then, it should quickly turn biomass and CO2 into fuels and chemicals. This paper gives an overview of some recent studies on hydrothermal conversion of biomass such as carbohydrate, lignin, and glycerin into value-added chemicals. Some recent advance in hydrothermal reduction of CO2 is also presented. ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=26201404
in Industrial & engineering chemistry research > Vol. 51 N° 30 (Août 2012) . - pp. 9921-9937[article] A Potentially useful technology by mimicking nature — rapid conversion of biomass and CO2 into chemicals and fuels under hydrothermal conditions [texte imprimé] / Fangming Jin, Auteur ; Xu Zeng, Auteur ; Zhenzi Jing, Auteur . - 2012 . - pp. 9921-9937.
Industrial chemistry
Langues : Anglais (eng)
in Industrial & engineering chemistry research > Vol. 51 N° 30 (Août 2012) . - pp. 9921-9937
Mots-clés : Hydrothermal condition Fuel Carbon dioxide Biomass Résumé : To diminish a serious global energy crisis and global warming caused by the imbalance between the slow formation of fossil fuels and rapid consumption by human activities, the developing of the technology for quickly turning biomass and CO2 into fuels and chemicals is needed. Hydrothermal reactions, which can be recognized as an effective pathway in the carbon cycle, played an important role in forming petroleum, natural gas, and coal from organic wastes. If humans could simulate the natural phenomena of the formation of fossils, then, it should quickly turn biomass and CO2 into fuels and chemicals. This paper gives an overview of some recent studies on hydrothermal conversion of biomass such as carbohydrate, lignin, and glycerin into value-added chemicals. Some recent advance in hydrothermal reduction of CO2 is also presented. ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=26201404 Exemplaires
Code-barres Cote Support Localisation Section Disponibilité aucun exemplaire
Titre : Calcium looping process for clean coal conversion : Design and operation of the subpilot - scale carbonator Type de document : texte imprimé Auteurs : Nihar Phalak, Auteur ; Shwetha Ramkumar, Auteur ; Niranjani Deshpande, Auteur Année de publication : 2012 Article en page(s) : pp. 9938-9944 Note générale : Industrial chemistry Langues : Anglais (eng) Mots-clés : Design Coal Résumé : The calcium looping process (CLP), which is being developed at The Ohio State University (OSU), is a clean coal technology for the production of hydrogen (H2) and electricity from coal-derived syngas. It integrates the water―gas shift (WGS) reaction with in situ removal of carbon dioxide (CO2) and other contaminants like sulfides and halides, thus resulting in the production of high-purity H2, The in situ removal of CO2 drives the equilibrium-limited WGS reaction forward. The CLP has the potential to reduce the overall footprint of a coal-to-H2 process because of the integration of several unit operations in a single-stage reactor. The high-temperature operation and the different exothermic reactions involved provide various sources of heat, which, when integrated appropriately, result in a process with low energy penalty. Prior work conducted in a fixed-bed reactor has shown that high carbon monoxide (CO) conversions and high H2 purities can be obtained, depending on the operating pressures. On the basis of the encouraging results obtained from the fixed-bed reactor, a subpilot-scale fluidized-bed reactor (carbonator) has been designed and constructed at OSU. In this work, the design of this reactor has been detailed and some operational results have been provided. ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=26201405
in Industrial & engineering chemistry research > Vol. 51 N° 30 (Août 2012) . - pp. 9938-9944[article] Calcium looping process for clean coal conversion : Design and operation of the subpilot - scale carbonator [texte imprimé] / Nihar Phalak, Auteur ; Shwetha Ramkumar, Auteur ; Niranjani Deshpande, Auteur . - 2012 . - pp. 9938-9944.
Industrial chemistry
Langues : Anglais (eng)
in Industrial & engineering chemistry research > Vol. 51 N° 30 (Août 2012) . - pp. 9938-9944
Mots-clés : Design Coal Résumé : The calcium looping process (CLP), which is being developed at The Ohio State University (OSU), is a clean coal technology for the production of hydrogen (H2) and electricity from coal-derived syngas. It integrates the water―gas shift (WGS) reaction with in situ removal of carbon dioxide (CO2) and other contaminants like sulfides and halides, thus resulting in the production of high-purity H2, The in situ removal of CO2 drives the equilibrium-limited WGS reaction forward. The CLP has the potential to reduce the overall footprint of a coal-to-H2 process because of the integration of several unit operations in a single-stage reactor. The high-temperature operation and the different exothermic reactions involved provide various sources of heat, which, when integrated appropriately, result in a process with low energy penalty. Prior work conducted in a fixed-bed reactor has shown that high carbon monoxide (CO) conversions and high H2 purities can be obtained, depending on the operating pressures. On the basis of the encouraging results obtained from the fixed-bed reactor, a subpilot-scale fluidized-bed reactor (carbonator) has been designed and constructed at OSU. In this work, the design of this reactor has been detailed and some operational results have been provided. ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=26201405 Exemplaires
Code-barres Cote Support Localisation Section Disponibilité aucun exemplaire
Titre : Cobalt phosphate – ZnO composite photocatalysts for oxygen evolution from photocatalytic water oxidation Type de document : texte imprimé Auteurs : Yabo Wang, Auteur ; Yongsheng Wang, Auteur ; Rongrong Jiang, Auteur Année de publication : 2012 Article en page(s) : pp. 9945–9951 Note générale : Industrial chemistry Langues : Anglais (eng) Mots-clés : Photocatalysts Oxygen evolution Résumé : Cobalt based oxygen evolution catalysts (Co–Pi) were loaded on the surface of ZnO by photochemical deposition in a neutral phosphate buffer solution containing Co2+ ions. Structural, morphological, and optical properties of the samples were characterized by X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), transmission electron microscopy, X-ray photoelectron spectroscopy, and UV–vis diffuse reflectance spectra techniques. The Co–Pi phase formed was amorphous and was deposited on the surface of ZnO uniformly as a layer of nanoparticles. The enhanced activity for oxygen evolution was directly observed from photocatalytic water oxidation over Co–Pi loaded ZnO. The oxygen produced in the first hour was more than 4 times of that obtained over ZnO alone. The results suggest that Co–Pi played the role of cocatalyst, which can trap photogenerated holes, leading to the enhancement of electron and hole separation efficiency. Further studies showed that the mixture of cobalt phosphate and ZnO exhibited similar enhancement in activity for oxygen evolution which could be due to the oxidation of nonactive cobalt(II) phosphate to active Co–Pi with higher oxidation states of cobalt upon light illumination during photocatalytic water oxidation process. In both systems, ZnO photocorrosion was observed based on inductively coupled plasma, XRD, and FESEM analyses. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie2027469
in Industrial & engineering chemistry research > Vol. 51 N° 30 (Août 2012) . - pp. 9945–9951[article] Cobalt phosphate – ZnO composite photocatalysts for oxygen evolution from photocatalytic water oxidation [texte imprimé] / Yabo Wang, Auteur ; Yongsheng Wang, Auteur ; Rongrong Jiang, Auteur . - 2012 . - pp. 9945–9951.
Industrial chemistry
Langues : Anglais (eng)
in Industrial & engineering chemistry research > Vol. 51 N° 30 (Août 2012) . - pp. 9945–9951
Mots-clés : Photocatalysts Oxygen evolution Résumé : Cobalt based oxygen evolution catalysts (Co–Pi) were loaded on the surface of ZnO by photochemical deposition in a neutral phosphate buffer solution containing Co2+ ions. Structural, morphological, and optical properties of the samples were characterized by X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), transmission electron microscopy, X-ray photoelectron spectroscopy, and UV–vis diffuse reflectance spectra techniques. The Co–Pi phase formed was amorphous and was deposited on the surface of ZnO uniformly as a layer of nanoparticles. The enhanced activity for oxygen evolution was directly observed from photocatalytic water oxidation over Co–Pi loaded ZnO. The oxygen produced in the first hour was more than 4 times of that obtained over ZnO alone. The results suggest that Co–Pi played the role of cocatalyst, which can trap photogenerated holes, leading to the enhancement of electron and hole separation efficiency. Further studies showed that the mixture of cobalt phosphate and ZnO exhibited similar enhancement in activity for oxygen evolution which could be due to the oxidation of nonactive cobalt(II) phosphate to active Co–Pi with higher oxidation states of cobalt upon light illumination during photocatalytic water oxidation process. In both systems, ZnO photocorrosion was observed based on inductively coupled plasma, XRD, and FESEM analyses. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie2027469 Exemplaires
Code-barres Cote Support Localisation Section Disponibilité aucun exemplaire
Titre : Ionic liquid engineering for lipase - mediated optical resolution of secondary alcohols : Design of ionic liquids applicable to ionic liquid coated - lipase catalyzed reaction Type de document : texte imprimé Auteurs : Yoshikazu Abe, Auteur ; Yusuke Yagi, Auteur ; Shuichi Hayase, Auteur Année de publication : 2012 Article en page(s) : pp. 9952-9958 Note générale : Industrial chemistry Langues : Anglais (eng) Mots-clés : Enzymatic catalysis Design Ionic liquid Résumé : A rational design of phosphonium ionic liquid for ionic liquid coated-lipase (IL1-PS)-catalyzed reaction has been investigated: very rapid transesterification of secondary alcohols was accomplished when IL1-PS was used as catalyst in tributyl((2-methoxyethoxy)methyl)phosphonium bis(trifluoromethanesulfonyl)amide ([P444MEM][NTf2]) or N-ethyl-N-((2-methoxyethoxy)methyl)-N-methylethanaminium bis(trifluoromethanesulfonyl)amide ([N221MEM[NTf2]) as solvent with excellent enantioselectivity. It was also revealed that ammonium ionic liquid influenced the lipase reactivity more strongly than phosphonium ionic liquids. Increased Kcat value was suggested to be the most important factor at work in IL1-PS in these ionic liquid solvents. The Kcat value of (S)-1-phenyethanol in [N44MEM][NTf2] was similar to that of i-Pr2O, and 1.6-fold acceleration was achieved for (R)-1-phenylethanol. On the other hand, the Km value for (R)-isomer in [N444MEM][NTf2] was slightly larger than the reaction in i-Pr2O, while it was significantly reduced for (S)-isomer. These results suggest that solvent provides a certain impact on the reactivity of the enzyme protein of IL1-PS. ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=26201407
in Industrial & engineering chemistry research > Vol. 51 N° 30 (Août 2012) . - pp. 9952-9958[article] Ionic liquid engineering for lipase - mediated optical resolution of secondary alcohols : Design of ionic liquids applicable to ionic liquid coated - lipase catalyzed reaction [texte imprimé] / Yoshikazu Abe, Auteur ; Yusuke Yagi, Auteur ; Shuichi Hayase, Auteur . - 2012 . - pp. 9952-9958.
Industrial chemistry
Langues : Anglais (eng)
in Industrial & engineering chemistry research > Vol. 51 N° 30 (Août 2012) . - pp. 9952-9958
Mots-clés : Enzymatic catalysis Design Ionic liquid Résumé : A rational design of phosphonium ionic liquid for ionic liquid coated-lipase (IL1-PS)-catalyzed reaction has been investigated: very rapid transesterification of secondary alcohols was accomplished when IL1-PS was used as catalyst in tributyl((2-methoxyethoxy)methyl)phosphonium bis(trifluoromethanesulfonyl)amide ([P444MEM][NTf2]) or N-ethyl-N-((2-methoxyethoxy)methyl)-N-methylethanaminium bis(trifluoromethanesulfonyl)amide ([N221MEM[NTf2]) as solvent with excellent enantioselectivity. It was also revealed that ammonium ionic liquid influenced the lipase reactivity more strongly than phosphonium ionic liquids. Increased Kcat value was suggested to be the most important factor at work in IL1-PS in these ionic liquid solvents. The Kcat value of (S)-1-phenyethanol in [N44MEM][NTf2] was similar to that of i-Pr2O, and 1.6-fold acceleration was achieved for (R)-1-phenylethanol. On the other hand, the Km value for (R)-isomer in [N444MEM][NTf2] was slightly larger than the reaction in i-Pr2O, while it was significantly reduced for (S)-isomer. These results suggest that solvent provides a certain impact on the reactivity of the enzyme protein of IL1-PS. ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=26201407 Exemplaires
Code-barres Cote Support Localisation Section Disponibilité aucun exemplaire
Titre : Transesterification of triolein to biodiesel using sodium - loaded catalysts prepared from zeolites Type de document : texte imprimé Auteurs : Yu-Yuan Wang, Auteur ; Tan Hiep Dang, Auteur ; Bing-Hung Chen, Auteur Année de publication : 2012 Article en page(s) : pp. 9959-9965 Note générale : Industrial chemistry Langues : Anglais (eng) Mots-clés : Zeolite Catalyst Transesterification Résumé : Transesterification of triolein in excess methanol over sodium-loaded catalysts prepared from Na-ion exchange with zeolites at a relatively lower reaction temperature, namely, at 60 °C, is studied in this work, Two zeolites, i.e., as-synthesized Zeolite MCM-22 and commercial Zeolite HY (CBV-780), are employed in this study. Although both zeolites show to some extent the capability of catalyzing transesterification of triolein in methanol to biodiesel, the resulting yields are only ca. 90% for CBV-780 after a 40-h reaction and 16.3% for MCM-22 after a 90-h reaction. In contrast, the conversion yields are much improved with Na-ion exchange to the surface of zeolite catalysts. For example, the yields of triolein to biodiesel have reached 98% and 99% within a 5.5-h reaction, respectively, using the NaOH-treated CBV-780 and MCM-22 catalysts, even if these NaOH-treated catalysts become amorphous and have suffered a loss of the Brunauer―Emmett―Teller surface area. Furthermore, no saponification was observed using these NaOH-treated catalysts. ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=26201408
in Industrial & engineering chemistry research > Vol. 51 N° 30 (Août 2012) . - pp. 9959-9965[article] Transesterification of triolein to biodiesel using sodium - loaded catalysts prepared from zeolites [texte imprimé] / Yu-Yuan Wang, Auteur ; Tan Hiep Dang, Auteur ; Bing-Hung Chen, Auteur . - 2012 . - pp. 9959-9965.
Industrial chemistry
Langues : Anglais (eng)
in Industrial & engineering chemistry research > Vol. 51 N° 30 (Août 2012) . - pp. 9959-9965
Mots-clés : Zeolite Catalyst Transesterification Résumé : Transesterification of triolein in excess methanol over sodium-loaded catalysts prepared from Na-ion exchange with zeolites at a relatively lower reaction temperature, namely, at 60 °C, is studied in this work, Two zeolites, i.e., as-synthesized Zeolite MCM-22 and commercial Zeolite HY (CBV-780), are employed in this study. Although both zeolites show to some extent the capability of catalyzing transesterification of triolein in methanol to biodiesel, the resulting yields are only ca. 90% for CBV-780 after a 40-h reaction and 16.3% for MCM-22 after a 90-h reaction. In contrast, the conversion yields are much improved with Na-ion exchange to the surface of zeolite catalysts. For example, the yields of triolein to biodiesel have reached 98% and 99% within a 5.5-h reaction, respectively, using the NaOH-treated CBV-780 and MCM-22 catalysts, even if these NaOH-treated catalysts become amorphous and have suffered a loss of the Brunauer―Emmett―Teller surface area. Furthermore, no saponification was observed using these NaOH-treated catalysts. ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=26201408 Exemplaires
Code-barres Cote Support Localisation Section Disponibilité aucun exemplaire
Titre : Excellent durability of substoichiometric titanium oxide as a catalyst support for Pd in alkaline direct ethanol fuel cells Type de document : texte imprimé Auteurs : Son Truong Nguyen, Auteur ; Jong-Min Lee, Auteur ; Yanhui Yang, Auteur Année de publication : 2012 Article en page(s) : pp. 9966-9972 Note générale : Industrial chemistry Langues : Anglais (eng) Mots-clés : Fuel cell Catalyst support Titanium oxide Durability Résumé : In this study, substoichiometric titanium oxide, TinO2n―1, was compared with carbon black and TiO2 in the role of catalyst supports for Pd in alkaline direct ethanol fuel cell. 10%Pd/C, 10% Pd/commercial TiO2 and 10%Pd/TinO2n―1 catalysts were successfully prepared by a polyol method The supports and electrocatalysts were characterized by X-ray diffraction (XRD), nitrogen adsorption, electrochemical impedance spectroscopy (EIS), cyclic voltammetry (CV), linear sweep voltammetry (LSV), and chronoamperometry (CA) techniques. Excellent durability was found for TinO2n―1 with holding potential and multiscan tests in N2-purged 1 M KOH solution. Among the three catalysts, Pd/TinO2n―1 showed the best activity and stability for ethanol electrooxidation in alkaline media. ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=26201409
in Industrial & engineering chemistry research > Vol. 51 N° 30 (Août 2012) . - pp. 9966-9972[article] Excellent durability of substoichiometric titanium oxide as a catalyst support for Pd in alkaline direct ethanol fuel cells [texte imprimé] / Son Truong Nguyen, Auteur ; Jong-Min Lee, Auteur ; Yanhui Yang, Auteur . - 2012 . - pp. 9966-9972.
Industrial chemistry
Langues : Anglais (eng)
in Industrial & engineering chemistry research > Vol. 51 N° 30 (Août 2012) . - pp. 9966-9972
Mots-clés : Fuel cell Catalyst support Titanium oxide Durability Résumé : In this study, substoichiometric titanium oxide, TinO2n―1, was compared with carbon black and TiO2 in the role of catalyst supports for Pd in alkaline direct ethanol fuel cell. 10%Pd/C, 10% Pd/commercial TiO2 and 10%Pd/TinO2n―1 catalysts were successfully prepared by a polyol method The supports and electrocatalysts were characterized by X-ray diffraction (XRD), nitrogen adsorption, electrochemical impedance spectroscopy (EIS), cyclic voltammetry (CV), linear sweep voltammetry (LSV), and chronoamperometry (CA) techniques. Excellent durability was found for TinO2n―1 with holding potential and multiscan tests in N2-purged 1 M KOH solution. Among the three catalysts, Pd/TinO2n―1 showed the best activity and stability for ethanol electrooxidation in alkaline media. ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=26201409 Exemplaires
Code-barres Cote Support Localisation Section Disponibilité aucun exemplaire
Titre : A Solid - state reaction route to anchoring Ni(OH)2 nanoparticles on reduced graphene oxide sheets for supercapacitors Type de document : texte imprimé Auteurs : Zhipeng Sun, Auteur ; Xianmao Lu, Auteur Année de publication : 2012 Article en page(s) : pp. 9973-9979 Note générale : Industrial chemistry Langues : Anglais (eng) Mots-clés : Nanoparticle Solid state reaction Résumé : A mechanically assisted solid-state reaction method is employed to prepare graphene[Ni(OH)2 nanocomposites for supercapacitor electrode materials. Morphological analyses reveal that, at a loading 50 wt % Ni(OH)2, nanoparticles with an average size of ∼10 nm are formed and uniformly dispersed on the surface of reduced graphene oxide sheets functionalized with benzenesulfonate. Electrochemical measurements of the composite material show a high specific capacitance of 1568 F g―1 (based on nickel hydroxide) at a current density of 4 A g―1, significantly higher than that of bare Ni(OH)2 nanoparticles prepared without the use of graphene. This much improved electrochemical performance is enabled by both the well-dispersed Ni(OH)2 nanoparticles that offer large accessible surface area and the hydrophilic functional groups on graphene surface that facilitate electrolyte transport. The scalable solid-state synthesis developed in this work is promising for a green chemical approach to the preparation of supercapacitor electrode materials with high performance. ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=26201410
in Industrial & engineering chemistry research > Vol. 51 N° 30 (Août 2012) . - pp. 9973-9979[article] A Solid - state reaction route to anchoring Ni(OH)2 nanoparticles on reduced graphene oxide sheets for supercapacitors [texte imprimé] / Zhipeng Sun, Auteur ; Xianmao Lu, Auteur . - 2012 . - pp. 9973-9979.
Industrial chemistry
Langues : Anglais (eng)
in Industrial & engineering chemistry research > Vol. 51 N° 30 (Août 2012) . - pp. 9973-9979
Mots-clés : Nanoparticle Solid state reaction Résumé : A mechanically assisted solid-state reaction method is employed to prepare graphene[Ni(OH)2 nanocomposites for supercapacitor electrode materials. Morphological analyses reveal that, at a loading 50 wt % Ni(OH)2, nanoparticles with an average size of ∼10 nm are formed and uniformly dispersed on the surface of reduced graphene oxide sheets functionalized with benzenesulfonate. Electrochemical measurements of the composite material show a high specific capacitance of 1568 F g―1 (based on nickel hydroxide) at a current density of 4 A g―1, significantly higher than that of bare Ni(OH)2 nanoparticles prepared without the use of graphene. This much improved electrochemical performance is enabled by both the well-dispersed Ni(OH)2 nanoparticles that offer large accessible surface area and the hydrophilic functional groups on graphene surface that facilitate electrolyte transport. The scalable solid-state synthesis developed in this work is promising for a green chemical approach to the preparation of supercapacitor electrode materials with high performance. ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=26201410 Exemplaires
Code-barres Cote Support Localisation Section Disponibilité aucun exemplaire
Titre : Design of entire energy system for chemical plants Type de document : texte imprimé Auteurs : Cheng-Liang Chen, Auteur ; Chih-Yao Lin, Auteur Année de publication : 2012 Article en page(s) : pp. 9980-9996 Note générale : Industrial chemistry Langues : Anglais (eng) Mots-clés : Chemical plant Design Résumé : This paper presents a systematic methodology for the synthesis of an entire energy system for chemical plants, which explores the interactions between the steam network and the heat recovery networks of process plants. The energy system is designed not only to meet the heating and power demands from an individual chemical process, but also to consider possibilities of energy transfer among holistic sites. In this paper, energy utilization across different plants is studied. Specifically, indirect and direct energy integation strategies are adopted for the design of the whole energy system to maximize the possible integration. With the energy integration strategies for the overall systems, the utility consumption can be reduced and the total annualized cost minimized. Case studies are presented to demonstrate the applicability and significant economic benefits of the proposed model when applied to industrial problems. ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=26201411
in Industrial & engineering chemistry research > Vol. 51 N° 30 (Août 2012) . - pp. 9980-9996[article] Design of entire energy system for chemical plants [texte imprimé] / Cheng-Liang Chen, Auteur ; Chih-Yao Lin, Auteur . - 2012 . - pp. 9980-9996.
Industrial chemistry
Langues : Anglais (eng)
in Industrial & engineering chemistry research > Vol. 51 N° 30 (Août 2012) . - pp. 9980-9996
Mots-clés : Chemical plant Design Résumé : This paper presents a systematic methodology for the synthesis of an entire energy system for chemical plants, which explores the interactions between the steam network and the heat recovery networks of process plants. The energy system is designed not only to meet the heating and power demands from an individual chemical process, but also to consider possibilities of energy transfer among holistic sites. In this paper, energy utilization across different plants is studied. Specifically, indirect and direct energy integation strategies are adopted for the design of the whole energy system to maximize the possible integration. With the energy integration strategies for the overall systems, the utility consumption can be reduced and the total annualized cost minimized. Case studies are presented to demonstrate the applicability and significant economic benefits of the proposed model when applied to industrial problems. ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=26201411 Exemplaires
Code-barres Cote Support Localisation Section Disponibilité aucun exemplaire
Titre : Exergy analysis of biomass drying based on self - heat recuperation technology and its application to industry : A simulation and experimental study Type de document : texte imprimé Auteurs : Yuping Liu, Auteur ; Muhammad Aziz, Auteur ; Chihiro Fushimi, Auteur Année de publication : 2012 Article en page(s) : pp. 9997-10007 Note générale : Industrial chemistry Langues : Anglais (eng) Mots-clés : Drying Biomass Exergy analysis Résumé : An energy-saving process for biomass drying was proposed to improve the overall energy efficiency by using self-heat recuperation technology for future industrial use. Energy analysis based on the simulation results showed that the primary energy consumption and CO2 emission in the proposed process can be decreased to 74% and 36% of that of the conventional heat recovery dryer, respectively. Moreover, exergy analysis was conducted to clarify exergy losses in the proposed drying process, and further energy-saving solutions were raised to minimize exergy loss based on exergy recuperation theory. The experimental results indicated that three times of the minimum fluidization velocity was a necessary condition for good fluidization. It was also confirmed that the proposed fluidized bed dryer for biomass drying achieves stable performance for more than 2 h in the experiments. ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=26201412
in Industrial & engineering chemistry research > Vol. 51 N° 30 (Août 2012) . - pp. 9997-10007[article] Exergy analysis of biomass drying based on self - heat recuperation technology and its application to industry : A simulation and experimental study [texte imprimé] / Yuping Liu, Auteur ; Muhammad Aziz, Auteur ; Chihiro Fushimi, Auteur . - 2012 . - pp. 9997-10007.
Industrial chemistry
Langues : Anglais (eng)
in Industrial & engineering chemistry research > Vol. 51 N° 30 (Août 2012) . - pp. 9997-10007
Mots-clés : Drying Biomass Exergy analysis Résumé : An energy-saving process for biomass drying was proposed to improve the overall energy efficiency by using self-heat recuperation technology for future industrial use. Energy analysis based on the simulation results showed that the primary energy consumption and CO2 emission in the proposed process can be decreased to 74% and 36% of that of the conventional heat recovery dryer, respectively. Moreover, exergy analysis was conducted to clarify exergy losses in the proposed drying process, and further energy-saving solutions were raised to minimize exergy loss based on exergy recuperation theory. The experimental results indicated that three times of the minimum fluidization velocity was a necessary condition for good fluidization. It was also confirmed that the proposed fluidized bed dryer for biomass drying achieves stable performance for more than 2 h in the experiments. ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=26201412 Exemplaires
Code-barres Cote Support Localisation Section Disponibilité aucun exemplaire
Titre : Enhanced production of bioxylitol from corn cobs by candida magnoliae Type de document : texte imprimé Auteurs : Kiyoshi Tada, Auteur ; Tohru Kanno, Auteur ; Jun-ichi Horiuchi, Auteur Année de publication : 2012 Article en page(s) : pp. 10008-10014 Note générale : Industrial chemistry Langues : Anglais (eng) Mots-clés : Production Résumé : An effective microbial process using Candida magnoliae was developed for xylitol production from xylose obtained from com cob. The hydrolysate containing approximately 25 g-xylose/L and 3.0 g-glucose/L was obtained from 100 g-corn cobs/L by 1.0―3.096 sulfuric acid with 60 min of hydrolysis time. The com cob hydrolysate was then treated by charcoal pellets which selectively removed more than 90% of inhibitors without affecting xylose concentration. Using the hydrolysate medium treated with the charcoal pellets, xylitol production using C. magnolia was successfully performed, resulting in a final production of approximately 18 g-xylitol/L from 25 g-xylose/L within 36 h. In total, 15―18 g xylitol could be produced from 100 g of com cobs. From the batch experiments operated under strictly controlled oxygen supply conditions, it was found that the successful xylitol production occurred at the narrow range of the oxygen transfer rate (OTR) from 0.8 mmol-O2/L·h to 4.7 mmol·O2/L·h. A two-step fermentation consisting of the cell growth step using normal hydrolysate medium and the xylitol production step using the concentrated corn cob hydrolysate was effective to avoid serious inhibitory effect and to realize a high concentration of xylitol production (approximately 49 g/L). ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=26201413
in Industrial & engineering chemistry research > Vol. 51 N° 30 (Août 2012) . - pp. 10008-10014[article] Enhanced production of bioxylitol from corn cobs by candida magnoliae [texte imprimé] / Kiyoshi Tada, Auteur ; Tohru Kanno, Auteur ; Jun-ichi Horiuchi, Auteur . - 2012 . - pp. 10008-10014.
Industrial chemistry
Langues : Anglais (eng)
in Industrial & engineering chemistry research > Vol. 51 N° 30 (Août 2012) . - pp. 10008-10014
Mots-clés : Production Résumé : An effective microbial process using Candida magnoliae was developed for xylitol production from xylose obtained from com cob. The hydrolysate containing approximately 25 g-xylose/L and 3.0 g-glucose/L was obtained from 100 g-corn cobs/L by 1.0―3.096 sulfuric acid with 60 min of hydrolysis time. The com cob hydrolysate was then treated by charcoal pellets which selectively removed more than 90% of inhibitors without affecting xylose concentration. Using the hydrolysate medium treated with the charcoal pellets, xylitol production using C. magnolia was successfully performed, resulting in a final production of approximately 18 g-xylitol/L from 25 g-xylose/L within 36 h. In total, 15―18 g xylitol could be produced from 100 g of com cobs. From the batch experiments operated under strictly controlled oxygen supply conditions, it was found that the successful xylitol production occurred at the narrow range of the oxygen transfer rate (OTR) from 0.8 mmol-O2/L·h to 4.7 mmol·O2/L·h. A two-step fermentation consisting of the cell growth step using normal hydrolysate medium and the xylitol production step using the concentrated corn cob hydrolysate was effective to avoid serious inhibitory effect and to realize a high concentration of xylitol production (approximately 49 g/L). ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=26201413 Exemplaires
Code-barres Cote Support Localisation Section Disponibilité aucun exemplaire
Titre : Continuous - time optimization model for source – sink matching in carbon capture and storage systems Type de document : texte imprimé Auteurs : Raymond R. Tan, Auteur ; Kathleen B. Aviso, Auteur Année de publication : 2012 Article en page(s) : pp. 10015-10020 Note générale : Industrial chemistry Langues : Anglais (eng) Mots-clés : Storage Modeling Optimization Continuous time Résumé : Carbon capture and storage (CCS) is widely considered to be an essential technology for reducing carbon dioxide (CO2) emissions from sources such as power plants. It involves isolating CO2 from exhaust gases and then storing it in an appropriate natural reservoir that acts as a sink. Therefore, CCS is able to prevent CO2 from entering the atmosphere. In this work, a continuous-time mixed integer nonlinear programming (MINLP) model for CO2 source-sink matching in CCS systems is developed; the initial model is then converted into an equivalent mixed integer linear program (MILP). It is assumed that in CCS systems, CO2 sources have fixed flow rates and operating lives, while CO2 sinks have an earliest time of availability and a maximum CO2 storage capacity. Thus, the resulting optimization model focuses on important physical and temporal aspects of planning CCS. The usefulness of the model is illustrated using two case studies. ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=26201414
in Industrial & engineering chemistry research > Vol. 51 N° 30 (Août 2012) . - pp. 10015-10020[article] Continuous - time optimization model for source – sink matching in carbon capture and storage systems [texte imprimé] / Raymond R. Tan, Auteur ; Kathleen B. Aviso, Auteur . - 2012 . - pp. 10015-10020.
Industrial chemistry
Langues : Anglais (eng)
in Industrial & engineering chemistry research > Vol. 51 N° 30 (Août 2012) . - pp. 10015-10020
Mots-clés : Storage Modeling Optimization Continuous time Résumé : Carbon capture and storage (CCS) is widely considered to be an essential technology for reducing carbon dioxide (CO2) emissions from sources such as power plants. It involves isolating CO2 from exhaust gases and then storing it in an appropriate natural reservoir that acts as a sink. Therefore, CCS is able to prevent CO2 from entering the atmosphere. In this work, a continuous-time mixed integer nonlinear programming (MINLP) model for CO2 source-sink matching in CCS systems is developed; the initial model is then converted into an equivalent mixed integer linear program (MILP). It is assumed that in CCS systems, CO2 sources have fixed flow rates and operating lives, while CO2 sinks have an earliest time of availability and a maximum CO2 storage capacity. Thus, the resulting optimization model focuses on important physical and temporal aspects of planning CCS. The usefulness of the model is illustrated using two case studies. ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=26201414 Exemplaires
Code-barres Cote Support Localisation Section Disponibilité aucun exemplaire
Titre : Design and optimization of natural gas liquefaction and recovery processes for offshore floating liquefied natural gas plants Type de document : texte imprimé Auteurs : Sanggyu Lee, Auteur ; Nguyen Van Duc Long, Auteur ; Moonyong Lee, Auteur Année de publication : 2012 Article en page(s) : pp. 10021-10030 Langues : Anglais (eng) Mots-clés : LNG Liquefaction Natural gas Optimization Design Résumé : A natural gas liquefaction and liquid recovery sequence is proposed for top-side offshore floating liquefied natural gas processing. During liquefaction, a single mixed refrigerant is separated into heavy and light key components, separately compressed after the main cryogenic heat exchanger and then mixed again to make a single mixed refrigerant. The proposed liquefaction cycle has a simple, compact structure and is suitable for power-efficient, offshore, floating liquefied natural gas liquefaction. The natural gas liquid recovery process employs space- and energy-efficient dividing wall columns for the integration of depropanization and debutanization. The columns were optimized by response surface methodology. A compact top dividing wall column configuration could reduce total annual costs. A combined process integrating natural gas liquefaction and liquid recovery is finally proposed. ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=26201415
in Industrial & engineering chemistry research > Vol. 51 N° 30 (Août 2012) . - pp. 10021-10030[article] Design and optimization of natural gas liquefaction and recovery processes for offshore floating liquefied natural gas plants [texte imprimé] / Sanggyu Lee, Auteur ; Nguyen Van Duc Long, Auteur ; Moonyong Lee, Auteur . - 2012 . - pp. 10021-10030.
Langues : Anglais (eng)
in Industrial & engineering chemistry research > Vol. 51 N° 30 (Août 2012) . - pp. 10021-10030
Mots-clés : LNG Liquefaction Natural gas Optimization Design Résumé : A natural gas liquefaction and liquid recovery sequence is proposed for top-side offshore floating liquefied natural gas processing. During liquefaction, a single mixed refrigerant is separated into heavy and light key components, separately compressed after the main cryogenic heat exchanger and then mixed again to make a single mixed refrigerant. The proposed liquefaction cycle has a simple, compact structure and is suitable for power-efficient, offshore, floating liquefied natural gas liquefaction. The natural gas liquid recovery process employs space- and energy-efficient dividing wall columns for the integration of depropanization and debutanization. The columns were optimized by response surface methodology. A compact top dividing wall column configuration could reduce total annual costs. A combined process integrating natural gas liquefaction and liquid recovery is finally proposed. ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=26201415 Exemplaires
Code-barres Cote Support Localisation Section Disponibilité aucun exemplaire
Titre : Understanding the effect of trace amount of water on CO2 capture in natural gas upgrading in metal – organic frameworks : A molecular simulation study Type de document : texte imprimé Auteurs : Hongliang Huang, Auteur ; Wenjuan Zhang, Auteur ; Dahuan Liu, Auteur Année de publication : 2012 Article en page(s) : pp. 10031-10038 Note générale : Industrial chemistry Langues : Anglais (eng) Mots-clés : Modeling Molecular model Upgrading Natural gas Carbon dioxide Résumé : In this work, molecular simulations were performed to investigate the effect of trace amount of water on CO2 capture in natural gas upgrading process in a diverse collection of 25 metal-organic frameworks (MOFs). The results show that the interaction between water molecules and MOFs plays a crucial role: at the condition of weak interaction, water molecules move freely in the materials and show a negligible effect on the adsorption selectivity of CO2/CH4; while when the interaction is strong enough that water molecules are adsorbed to the preferential adsorption sites in MOFs, the effect can be significant, depending on the strength of water adsorption. In this case, the electrostatic interaction produced by the MOF framework is the dominant factor. This work provides a better understanding of the different behaviors of water effect on CO2 capture observed previously that may guide the future application of MOFs in industrial separations. ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=26201416
in Industrial & engineering chemistry research > Vol. 51 N° 30 (Août 2012) . - pp. 10031-10038[article] Understanding the effect of trace amount of water on CO2 capture in natural gas upgrading in metal – organic frameworks : A molecular simulation study [texte imprimé] / Hongliang Huang, Auteur ; Wenjuan Zhang, Auteur ; Dahuan Liu, Auteur . - 2012 . - pp. 10031-10038.
Industrial chemistry
Langues : Anglais (eng)
in Industrial & engineering chemistry research > Vol. 51 N° 30 (Août 2012) . - pp. 10031-10038
Mots-clés : Modeling Molecular model Upgrading Natural gas Carbon dioxide Résumé : In this work, molecular simulations were performed to investigate the effect of trace amount of water on CO2 capture in natural gas upgrading process in a diverse collection of 25 metal-organic frameworks (MOFs). The results show that the interaction between water molecules and MOFs plays a crucial role: at the condition of weak interaction, water molecules move freely in the materials and show a negligible effect on the adsorption selectivity of CO2/CH4; while when the interaction is strong enough that water molecules are adsorbed to the preferential adsorption sites in MOFs, the effect can be significant, depending on the strength of water adsorption. In this case, the electrostatic interaction produced by the MOF framework is the dominant factor. This work provides a better understanding of the different behaviors of water effect on CO2 capture observed previously that may guide the future application of MOFs in industrial separations. ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=26201416 Exemplaires
Code-barres Cote Support Localisation Section Disponibilité aucun exemplaire
Titre : Thin - film composite membranes and formation mechanism of thin - film layers on hydrophilic cellulose acetate propionate substrates for forward osmosis processes Type de document : texte imprimé Auteurs : Xue Li, Auteur ; Kai Yu Wang, Auteur ; Bradley Helmer, Auteur Année de publication : 2012 Article en page(s) : pp. 10039–10050 Note générale : Industrial chemistry Langues : Anglais (eng) Mots-clés : Composite membranes Hydrophilic Résumé : For the first time, the potential of using hydrophilic cellulose acetate propionate (CAP) as microporous substrates for the fabrication of thin-film composite (TFC) forward osmosis (FO) membranes has been explored. Two types of TFC flat sheet membranes with well-designed substrate structures were prepared. The CAP-TFC membranes show very low Js/Jw ratios (i.e., the ratio of reverse draw solute flux to water flux) of about 0.05 g/L with reasonably high water fluxes under the pressure-retarded osmosis (PRO) mode using 2 M NaCl as the draw solution and deionized water as the feed. When using model seawater as the feed, the water flux is about 12.3 LMH which is comparable to the best in the literature. These results, combined with positron annihilation spectroscopy (PAS) data, confirm the hypothesis that a finger-like morphology in the substrate is not crucial to the performance of TFC FO membranes. Moreover, the surface and skin morphology of the substrate may play essential roles in the formation of the polyamide layer as well as its perfectness and FO performance. A dynamic scheme to elucidate the evolution of forming the globular and worm-like structure during the interfacial polymerization has been proposed. Substrates with larger pores and broader distribution may facilitate rapid migration of amine molecules, induce more complicated convection at the interface, and enlarge reaction contact area, resulting in a rougher but more compact polyamide layer in the TFC membranes, while smaller surface pores of substrate favor simple convection at the interface during the interfacial reaction, producing nascent cross-linked films with smaller domain sizes, smoother and less dense structure, and less defects. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie2027052
in Industrial & engineering chemistry research > Vol. 51 N° 30 (Août 2012) . - pp. 10039–10050[article] Thin - film composite membranes and formation mechanism of thin - film layers on hydrophilic cellulose acetate propionate substrates for forward osmosis processes [texte imprimé] / Xue Li, Auteur ; Kai Yu Wang, Auteur ; Bradley Helmer, Auteur . - 2012 . - pp. 10039–10050.
Industrial chemistry
Langues : Anglais (eng)
in Industrial & engineering chemistry research > Vol. 51 N° 30 (Août 2012) . - pp. 10039–10050
Mots-clés : Composite membranes Hydrophilic Résumé : For the first time, the potential of using hydrophilic cellulose acetate propionate (CAP) as microporous substrates for the fabrication of thin-film composite (TFC) forward osmosis (FO) membranes has been explored. Two types of TFC flat sheet membranes with well-designed substrate structures were prepared. The CAP-TFC membranes show very low Js/Jw ratios (i.e., the ratio of reverse draw solute flux to water flux) of about 0.05 g/L with reasonably high water fluxes under the pressure-retarded osmosis (PRO) mode using 2 M NaCl as the draw solution and deionized water as the feed. When using model seawater as the feed, the water flux is about 12.3 LMH which is comparable to the best in the literature. These results, combined with positron annihilation spectroscopy (PAS) data, confirm the hypothesis that a finger-like morphology in the substrate is not crucial to the performance of TFC FO membranes. Moreover, the surface and skin morphology of the substrate may play essential roles in the formation of the polyamide layer as well as its perfectness and FO performance. A dynamic scheme to elucidate the evolution of forming the globular and worm-like structure during the interfacial polymerization has been proposed. Substrates with larger pores and broader distribution may facilitate rapid migration of amine molecules, induce more complicated convection at the interface, and enlarge reaction contact area, resulting in a rougher but more compact polyamide layer in the TFC membranes, while smaller surface pores of substrate favor simple convection at the interface during the interfacial reaction, producing nascent cross-linked films with smaller domain sizes, smoother and less dense structure, and less defects. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie2027052 Exemplaires
Code-barres Cote Support Localisation Section Disponibilité aucun exemplaire
Titre : Membrane engineering for water engineering Type de document : texte imprimé Auteurs : Enrico Drioli, Auteur ; Francesca Macedonio, Auteur Année de publication : 2012 Article en page(s) : pp. 10051-10056 Note générale : Industrial chemistry Langues : Anglais (eng) Mots-clés : Membrane engineering Résumé : Today membrane engineering is giving interesting solutions to some of the major problems of our modern industrialized society. Membrane bioreactors (MBR) in municipal water treatments, membrane operations and integrated membrane systems in seawater and brackish water desalination are some important cases where membrane engineering is playing a dominant role. This manuscript discusses how membrane engineering contributes to the solution of this water problem. It gives also a vision on the current and future developments of membrane operations in the field of water treatment. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie2028188
in Industrial & engineering chemistry research > Vol. 51 N° 30 (Août 2012) . - pp. 10051-10056[article] Membrane engineering for water engineering [texte imprimé] / Enrico Drioli, Auteur ; Francesca Macedonio, Auteur . - 2012 . - pp. 10051-10056.
Industrial chemistry
Langues : Anglais (eng)
in Industrial & engineering chemistry research > Vol. 51 N° 30 (Août 2012) . - pp. 10051-10056
Mots-clés : Membrane engineering Résumé : Today membrane engineering is giving interesting solutions to some of the major problems of our modern industrialized society. Membrane bioreactors (MBR) in municipal water treatments, membrane operations and integrated membrane systems in seawater and brackish water desalination are some important cases where membrane engineering is playing a dominant role. This manuscript discusses how membrane engineering contributes to the solution of this water problem. It gives also a vision on the current and future developments of membrane operations in the field of water treatment. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie2028188 Exemplaires
Code-barres Cote Support Localisation Section Disponibilité aucun exemplaire
Titre : Sustainability and waste management in the resource industries Type de document : texte imprimé Auteurs : Hugh Jones, Auteur ; David V. Boger, Auteur Année de publication : 2012 Article en page(s) : pp. 10057–10065 Note générale : Industrial chemistry Langues : Anglais (eng) Mots-clés : Waste management Résumé : Fundamental science and engineering research at Monash University and The University of Melbourne in Australia has enabled the alumina industry worldwide to reduce the volume of waste produced by about fifty percent. Valuable raw materials are recovered, and the risk of storage failure is eliminated. Across the mining industry, there are at least two major storage failures annually worldwide, resulting in deaths and environmental disasters. The failure in Hungary of a storage facility for bauxite residue in October 2011 resulted in eight deaths and a fine of 472 million euro ($US648 million) and the arrest of the CEO (later released). The new technique called dry disposal produces a paste for stacking and drying instead of a water-like suspension to be stored in a dam or pond. Simply removing water from the suspension and reusing and recycling water represents a step toward a more sustainable practice in the industry. As the concentration of such a suspension is increased as a result of dewatering, the materials exhibit non-Newtonian behavior, characterized by shear thinning, a yield stress, and in some instances, thixotropic behavior. Such high concentration, nonideal (dirty) suspensions in the resource industries has meant that new rheological methods and techniques were needed for both shear and compression rheology to measure and interpret the basic flow properties. Also, some older empirical techniques needed to be modified and interpreted in a more fundamental way so that the results could be used in design. The paper reviews these techniques and illustrates how the industry itself has motivated their development. Understanding and exploiting this rheology has resulted in dramatic improvement in the waste disposal strategy for some industries, but many have failed to embrace the available technology. Why? Is regulation the answer? Probably not. The paper concludes that a greater positive change in the waste management practice will occur in the future, motivated by a number of factors, including public perception, water recovery, the necessity to earn the right to operate, and perhaps even by common sense accounting. The paper is a review of thirty years of work with the resource industries on environmental waste minimization. Aspects have been published in the Proceedings of Paste and Thickened Tailings Conferences held annually since 1999 (Jewell, R. J., Fourie, A. B., Eds.; Paste and Thickened Tailings–A Guide, Second ed.; Australian Centre for Geomechanics: Perth, 2006), in Chemical Engineering Science (Boger, D. V. Chem. Eng. Sci.2009, 64, 4525), and in the Proceedings of the Second International Future Mining Conference in 2011 (Jones, H.; Boger, D. V. Proceedings of the Second International Future Mining Conference 2011, Sydney, 22–23 November, 2011). ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie202963z
in Industrial & engineering chemistry research > Vol. 51 N° 30 (Août 2012) . - pp. 10057–10065[article] Sustainability and waste management in the resource industries [texte imprimé] / Hugh Jones, Auteur ; David V. Boger, Auteur . - 2012 . - pp. 10057–10065.
Industrial chemistry
Langues : Anglais (eng)
in Industrial & engineering chemistry research > Vol. 51 N° 30 (Août 2012) . - pp. 10057–10065
Mots-clés : Waste management Résumé : Fundamental science and engineering research at Monash University and The University of Melbourne in Australia has enabled the alumina industry worldwide to reduce the volume of waste produced by about fifty percent. Valuable raw materials are recovered, and the risk of storage failure is eliminated. Across the mining industry, there are at least two major storage failures annually worldwide, resulting in deaths and environmental disasters. The failure in Hungary of a storage facility for bauxite residue in October 2011 resulted in eight deaths and a fine of 472 million euro ($US648 million) and the arrest of the CEO (later released). The new technique called dry disposal produces a paste for stacking and drying instead of a water-like suspension to be stored in a dam or pond. Simply removing water from the suspension and reusing and recycling water represents a step toward a more sustainable practice in the industry. As the concentration of such a suspension is increased as a result of dewatering, the materials exhibit non-Newtonian behavior, characterized by shear thinning, a yield stress, and in some instances, thixotropic behavior. Such high concentration, nonideal (dirty) suspensions in the resource industries has meant that new rheological methods and techniques were needed for both shear and compression rheology to measure and interpret the basic flow properties. Also, some older empirical techniques needed to be modified and interpreted in a more fundamental way so that the results could be used in design. The paper reviews these techniques and illustrates how the industry itself has motivated their development. Understanding and exploiting this rheology has resulted in dramatic improvement in the waste disposal strategy for some industries, but many have failed to embrace the available technology. Why? Is regulation the answer? Probably not. The paper concludes that a greater positive change in the waste management practice will occur in the future, motivated by a number of factors, including public perception, water recovery, the necessity to earn the right to operate, and perhaps even by common sense accounting. The paper is a review of thirty years of work with the resource industries on environmental waste minimization. Aspects have been published in the Proceedings of Paste and Thickened Tailings Conferences held annually since 1999 (Jewell, R. J., Fourie, A. B., Eds.; Paste and Thickened Tailings–A Guide, Second ed.; Australian Centre for Geomechanics: Perth, 2006), in Chemical Engineering Science (Boger, D. V. Chem. Eng. Sci.2009, 64, 4525), and in the Proceedings of the Second International Future Mining Conference in 2011 (Jones, H.; Boger, D. V. Proceedings of the Second International Future Mining Conference 2011, Sydney, 22–23 November, 2011). ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie202963z Exemplaires
Code-barres Cote Support Localisation Section Disponibilité aucun exemplaire
Titre : Hydrocarbon fuels production from hydrocracking of soybean oil using transition metal carbides and nitrides supported on ZSM - 5 Type de document : texte imprimé Auteurs : Huali Wang, Auteur ; Shuli Yan, Auteur ; Steven O. Salley, Auteur Année de publication : 2012 Article en page(s) : pp. 10066-10073 Note générale : Industrial chemistry Langues : Anglais (eng) Mots-clés : Hydrocracking Production Fuel Résumé : The effects of process parameters and Ni/Mo atomic ratio on catalytic hydrocracking of soybean oil were investigated using the carbide or nitride forms of Ni/Mo supported on ZSM-5 catalysts. Essentially, a complete conversion of the triglycerides was observed at 650 psi and 360―450 °C. A low reaction temperature (360 °C) resulted in a significant change in selectivity toward hydrocarbon fuels. After a 4 day reaction, only 3―5% of hydrocarbon fuels were produced together with considerable amount of carboxyl acids (very high acid number up to 140 mg KOH/g). The gaseous phase products at 450 °C indicated that the nitride catalyst favors a methanation reaction more than the carbide catalyst by producing a larger amount of methane in the gaseous product. At a lower liquid hourly space velocity (1 h―1), about 70 wt % of gasoline to diesel range hydrocarbons were obtained in the organic liquid products compared to 25 wt % at 2 and 3 h―1. Increasing the Ni content in the catalyst improves the hydrogenation ability of the catalyst, since Ni is known to activate hydrogen and transfer protons and electrons to molybdenum. A larger fraction of gasoline was produced in the organic liquid product while similar jet and diesel range hydrocarbons were obtained by increasing the Ni/Mo atomic ratio from 0 to 1.5. However, a decreased fraction of the organic product was generated with an increasing amount of Ni content in the catalyst. Overall, the highest yield of hydrocarbon fuels (about 50 wt %) was obtained when the Ni/Mo molar ratio was 0.5. ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=26201420
in Industrial & engineering chemistry research > Vol. 51 N° 30 (Août 2012) . - pp. 10066-10073[article] Hydrocarbon fuels production from hydrocracking of soybean oil using transition metal carbides and nitrides supported on ZSM - 5 [texte imprimé] / Huali Wang, Auteur ; Shuli Yan, Auteur ; Steven O. Salley, Auteur . - 2012 . - pp. 10066-10073.
Industrial chemistry
Langues : Anglais (eng)
in Industrial & engineering chemistry research > Vol. 51 N° 30 (Août 2012) . - pp. 10066-10073
Mots-clés : Hydrocracking Production Fuel Résumé : The effects of process parameters and Ni/Mo atomic ratio on catalytic hydrocracking of soybean oil were investigated using the carbide or nitride forms of Ni/Mo supported on ZSM-5 catalysts. Essentially, a complete conversion of the triglycerides was observed at 650 psi and 360―450 °C. A low reaction temperature (360 °C) resulted in a significant change in selectivity toward hydrocarbon fuels. After a 4 day reaction, only 3―5% of hydrocarbon fuels were produced together with considerable amount of carboxyl acids (very high acid number up to 140 mg KOH/g). The gaseous phase products at 450 °C indicated that the nitride catalyst favors a methanation reaction more than the carbide catalyst by producing a larger amount of methane in the gaseous product. At a lower liquid hourly space velocity (1 h―1), about 70 wt % of gasoline to diesel range hydrocarbons were obtained in the organic liquid products compared to 25 wt % at 2 and 3 h―1. Increasing the Ni content in the catalyst improves the hydrogenation ability of the catalyst, since Ni is known to activate hydrogen and transfer protons and electrons to molybdenum. A larger fraction of gasoline was produced in the organic liquid product while similar jet and diesel range hydrocarbons were obtained by increasing the Ni/Mo atomic ratio from 0 to 1.5. However, a decreased fraction of the organic product was generated with an increasing amount of Ni content in the catalyst. Overall, the highest yield of hydrocarbon fuels (about 50 wt %) was obtained when the Ni/Mo molar ratio was 0.5. ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=26201420 Exemplaires
Code-barres Cote Support Localisation Section Disponibilité aucun exemplaire
Titre : Enhancing the conversion efficiency of semiconductor sensitized solar cells via the cosensitization of dual - sized quantum dots Type de document : texte imprimé Auteurs : Jun-Guo Song, Auteur ; Xin Song, Auteur ; Tao Ling, Auteur Année de publication : 2012 Article en page(s) : pp. 10074-10078 Note générale : Industrial chemistry Langues : Anglais (eng) Mots-clés : Conversion Semiconductor Solar Cells Résumé : Dual-sized CdS quantum dots were employed as light harvesters of solar cells to achieve high power conversion efficiency. Chemical bath deposition and annealing treatment were adopted to produce quantum dots with different sizes. The strategy of cosensitization by dual-sized CdS quantum dots was found effective to improve the performance of solar cells by forming a type-I band structure. Our work indicates that a reasonable configuration of quantum dots is crucial on boosting the performance of solar cells. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie300109u
in Industrial & engineering chemistry research > Vol. 51 N° 30 (Août 2012) . - pp. 10074-10078[article] Enhancing the conversion efficiency of semiconductor sensitized solar cells via the cosensitization of dual - sized quantum dots [texte imprimé] / Jun-Guo Song, Auteur ; Xin Song, Auteur ; Tao Ling, Auteur . - 2012 . - pp. 10074-10078.
Industrial chemistry
Langues : Anglais (eng)
in Industrial & engineering chemistry research > Vol. 51 N° 30 (Août 2012) . - pp. 10074-10078
Mots-clés : Conversion Semiconductor Solar Cells Résumé : Dual-sized CdS quantum dots were employed as light harvesters of solar cells to achieve high power conversion efficiency. Chemical bath deposition and annealing treatment were adopted to produce quantum dots with different sizes. The strategy of cosensitization by dual-sized CdS quantum dots was found effective to improve the performance of solar cells by forming a type-I band structure. Our work indicates that a reasonable configuration of quantum dots is crucial on boosting the performance of solar cells. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie300109u Exemplaires
Code-barres Cote Support Localisation Section Disponibilité aucun exemplaire
Titre : Kapok fiber oriented polyaniline for removal of sulfonated dyes Type de document : texte imprimé Auteurs : Yian Zheng, Auteur ; Yi Liu, Auteur ; Aiqin Wang, Auteur Année de publication : 2012 Article en page(s) : pp. 10079-10087 Note générale : Industrial chemistry Langues : Anglais (eng) Mots-clés : Dyes Résumé : In the present work, kapok fiber oriented polyaniline (KF-O-PAN) was prepared via a facile polymerization of aniline on the surface of KF and optimized using response surface methodology based on a central composite design. Adsorption characteristics of KF-O-PAN were examined using three sulfonated dyes, that is, Congo Red (CR), Orange II (OG-II), and Orange G (OG-G), as the model adsorbates. The effects of contact time, pH, initial dye concentration, and poly(vinyl alcohol) sizing on the amount of dye adsorbed were investigated using a batch experiment. The amount of dye adsorbed in different water bodies including distilled water, tap water, well water, and lake water was compared to study further the influence of ionic strength. The results indicate that the adsorption equilibrium can be achieved within 4 h, and the monolayer adsorption capacity calculated from the Langmuir equation is 40.82, 188.7, and 192.3 mg/g for CR, OG-II, and OG-G, respectively. KF-O-PAN shows a higher amount of dye adsorbed despite the influences of ionic strength when pH ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=26201422
in Industrial & engineering chemistry research > Vol. 51 N° 30 (Août 2012) . - pp. 10079-10087[article] Kapok fiber oriented polyaniline for removal of sulfonated dyes [texte imprimé] / Yian Zheng, Auteur ; Yi Liu, Auteur ; Aiqin Wang, Auteur . - 2012 . - pp. 10079-10087.
Industrial chemistry
Langues : Anglais (eng)
in Industrial & engineering chemistry research > Vol. 51 N° 30 (Août 2012) . - pp. 10079-10087
Mots-clés : Dyes Résumé : In the present work, kapok fiber oriented polyaniline (KF-O-PAN) was prepared via a facile polymerization of aniline on the surface of KF and optimized using response surface methodology based on a central composite design. Adsorption characteristics of KF-O-PAN were examined using three sulfonated dyes, that is, Congo Red (CR), Orange II (OG-II), and Orange G (OG-G), as the model adsorbates. The effects of contact time, pH, initial dye concentration, and poly(vinyl alcohol) sizing on the amount of dye adsorbed were investigated using a batch experiment. The amount of dye adsorbed in different water bodies including distilled water, tap water, well water, and lake water was compared to study further the influence of ionic strength. The results indicate that the adsorption equilibrium can be achieved within 4 h, and the monolayer adsorption capacity calculated from the Langmuir equation is 40.82, 188.7, and 192.3 mg/g for CR, OG-II, and OG-G, respectively. KF-O-PAN shows a higher amount of dye adsorbed despite the influences of ionic strength when pH ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=26201422 Exemplaires
Code-barres Cote Support Localisation Section Disponibilité aucun exemplaire
Titre : Blends of linear and long - chain branched poly (l - lactide)s with high melt strength and fast crystallization rate Type de document : texte imprimé Auteurs : Liangyan Wang, Auteur ; Xiabin Jing, Auteur ; Haibo Cheng, Auteur Année de publication : 2012 Article en page(s) : pp. 10088-10099 Note générale : Industrial chemistry Langues : Anglais (eng) Mots-clés : Crystallization Strength Résumé : The long-chain branched polylactides (LCB-PLAs) prepared by coupling the hydroryl-teaninated two-arm (linear) and triarm PLA prepolymers of identical arm length with hexamethylenediacianate (HDI) were used to improve the melt rheological and crystallization properties of linear polylactide resin, PLA 4032D from NatureWorks. The blends containing LCB-PLA displayed higher zero shear viscosities, more significant shear shinning, more melt elasticity, and much longer relaxation times together with significant strain hardening in elongational deformation. Tg, Tm and crystallinity (Xc) of linear PLA remained virtually unaffected, but the crystallization rate increased obviously, since the branch points of LCB-PLAs could play a role of nucleating agent. High melt strength, fast crystallization, and favorable miscibility improved the foaming ability of the linear/ LCB-PLA blends, substantially. ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=26201423
in Industrial & engineering chemistry research > Vol. 51 N° 30 (Août 2012) . - pp. 10088-10099[article] Blends of linear and long - chain branched poly (l - lactide)s with high melt strength and fast crystallization rate [texte imprimé] / Liangyan Wang, Auteur ; Xiabin Jing, Auteur ; Haibo Cheng, Auteur . - 2012 . - pp. 10088-10099.
Industrial chemistry
Langues : Anglais (eng)
in Industrial & engineering chemistry research > Vol. 51 N° 30 (Août 2012) . - pp. 10088-10099
Mots-clés : Crystallization Strength Résumé : The long-chain branched polylactides (LCB-PLAs) prepared by coupling the hydroryl-teaninated two-arm (linear) and triarm PLA prepolymers of identical arm length with hexamethylenediacianate (HDI) were used to improve the melt rheological and crystallization properties of linear polylactide resin, PLA 4032D from NatureWorks. The blends containing LCB-PLA displayed higher zero shear viscosities, more significant shear shinning, more melt elasticity, and much longer relaxation times together with significant strain hardening in elongational deformation. Tg, Tm and crystallinity (Xc) of linear PLA remained virtually unaffected, but the crystallization rate increased obviously, since the branch points of LCB-PLAs could play a role of nucleating agent. High melt strength, fast crystallization, and favorable miscibility improved the foaming ability of the linear/ LCB-PLA blends, substantially. ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=26201423 Exemplaires
Code-barres Cote Support Localisation Section Disponibilité aucun exemplaire
Titre : Investigation of parameters affecting gypsum dewatering properties in a wet flue gas desulphurization pilot plant Type de document : texte imprimé Auteurs : Brian B. Hansen, Auteur ; Soren Kiil, Auteur Année de publication : 2012 Article en page(s) : pp. 10100–10107 Note générale : Industrial chemistry Langues : Anglais (eng) Mots-clés : Gas Desulphurization Résumé : Wet flue gas desulphurization (FGD) plants with forced oxidation, installed at coal and oil fired power plants for removal of SO2(g), must produce gypsum of high quality. However, quality issues such as an excessive moisture content, due to poor gypsum dewatering properties, may occur from time to time. In this work, the particle size distribution, morphology, and filtration rate of wet FGD gypsum formed in a pilot-scale experimental setup, operated in forced oxidation mode, have been studied. The influence of holding tank residence time (10–408 h), solids content (30–169 g/L), and the presence of impurities (0.002 M Al2F6; 50 g quartz/L; 0.02 M Al3+, and 0.040 M Mg2+) were investigated. In addition, slurry from a full-scale wet FGD plant, experiencing formation of flat shaped crystals and poor gypsum dewatering properties, was transferred to the pilot plant to test if the plant would now start to produce low quality gypsum. The crystals formed in the pilot plant, on the basis of the full-scale slurry did, however, show acceptable filtration rates and crystal morphologies closer to the prismatic crystals from after pilot plant experiments with demineralized water. The gypsum slurry filtration rates were generally high, but a shorter residence time (10 h) and gypsum crystals experiencing breakage and/or attrition (408 h) showed slightly lower filtration rates. Both these experiments contained a higher fraction of fines, which may explain the slightly lower filtration rates. Crystals formed at a higher solids concentration and longer residence time (169 g/L and 120 h) showed a higher proportion of flat crystals, and the XRD pattern contained strong peaks at 31.1° (as the full-scale gypsum) and 29.1°, but no change in the filtration rate was obtained. It has not been possible in the pilot plant to form flat gypsum flakes with poor dewatering properties similar to those observed in full-scale plants. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie3005435
in Industrial & engineering chemistry research > Vol. 51 N° 30 (Août 2012) . - pp. 10100–10107[article] Investigation of parameters affecting gypsum dewatering properties in a wet flue gas desulphurization pilot plant [texte imprimé] / Brian B. Hansen, Auteur ; Soren Kiil, Auteur . - 2012 . - pp. 10100–10107.
Industrial chemistry
Langues : Anglais (eng)
in Industrial & engineering chemistry research > Vol. 51 N° 30 (Août 2012) . - pp. 10100–10107
Mots-clés : Gas Desulphurization Résumé : Wet flue gas desulphurization (FGD) plants with forced oxidation, installed at coal and oil fired power plants for removal of SO2(g), must produce gypsum of high quality. However, quality issues such as an excessive moisture content, due to poor gypsum dewatering properties, may occur from time to time. In this work, the particle size distribution, morphology, and filtration rate of wet FGD gypsum formed in a pilot-scale experimental setup, operated in forced oxidation mode, have been studied. The influence of holding tank residence time (10–408 h), solids content (30–169 g/L), and the presence of impurities (0.002 M Al2F6; 50 g quartz/L; 0.02 M Al3+, and 0.040 M Mg2+) were investigated. In addition, slurry from a full-scale wet FGD plant, experiencing formation of flat shaped crystals and poor gypsum dewatering properties, was transferred to the pilot plant to test if the plant would now start to produce low quality gypsum. The crystals formed in the pilot plant, on the basis of the full-scale slurry did, however, show acceptable filtration rates and crystal morphologies closer to the prismatic crystals from after pilot plant experiments with demineralized water. The gypsum slurry filtration rates were generally high, but a shorter residence time (10 h) and gypsum crystals experiencing breakage and/or attrition (408 h) showed slightly lower filtration rates. Both these experiments contained a higher fraction of fines, which may explain the slightly lower filtration rates. Crystals formed at a higher solids concentration and longer residence time (169 g/L and 120 h) showed a higher proportion of flat crystals, and the XRD pattern contained strong peaks at 31.1° (as the full-scale gypsum) and 29.1°, but no change in the filtration rate was obtained. It has not been possible in the pilot plant to form flat gypsum flakes with poor dewatering properties similar to those observed in full-scale plants. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie3005435 Exemplaires
Code-barres Cote Support Localisation Section Disponibilité aucun exemplaire
Titre : Solution combustion synthesis of nanosized copper chromite and its use as a burn rate modifier in solid propellants Type de document : texte imprimé Auteurs : P. S. Sathiskumar, Auteur ; C. R. Thomas, Auteur ; Giridhar Madras, Auteur Année de publication : 2012 Article en page(s) : pp. 10108–10116 Note générale : Industrial chemistry Langues : Anglais (eng) Mots-clés : Combustion Nanosized Résumé : Nano sized copper chromite, which is used as a burn rate accelerator for solid propellants, was synthesized by the solution combustion process using citric acid and glycine as fuel. Pure spinel phase copper chromite (CuCr2O4) was synthesized, and the effect of different ratios of Cu–Cr ions in the initial reactant and various calcination temperatures on the final properties of the material were examined. The reaction time for the synthesis with glycine was lower compared to that with citric acid. The synthesized samples from both fuel cycles were characterized by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), BET surface area analysis, and scanning electron microscope (SEM). Commercial copper chromite that is currently used in solid propellant formulation was also characterized by the same techniques. XRD analysis shows that the pure spinel phase compound is formed by calcination at 700 °C for glycine fuel cycle and between 750 and 800 °C for citric acid cycle. XPS results indicate the variation of the oxidation state of copper in the final compound with a change in the Cu–Cr mole ratio. SEM images confirm the formation of nano size spherical shape particles. The variation of BET surface area with calcination temperature was studied for the solution combusted catalyst. Burn rate evaluation of synthesized catalyst was carried out and compared with the commercial catalyst. The comparison between BET surface area and the burn rate depicts that surface area difference caused the variation in burn rate between samples. The reason behind the reduction in surface area and the required modifications in the process are also described. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie301435r
in Industrial & engineering chemistry research > Vol. 51 N° 30 (Août 2012) . - pp. 10108–10116[article] Solution combustion synthesis of nanosized copper chromite and its use as a burn rate modifier in solid propellants [texte imprimé] / P. S. Sathiskumar, Auteur ; C. R. Thomas, Auteur ; Giridhar Madras, Auteur . - 2012 . - pp. 10108–10116.
Industrial chemistry
Langues : Anglais (eng)
in Industrial & engineering chemistry research > Vol. 51 N° 30 (Août 2012) . - pp. 10108–10116
Mots-clés : Combustion Nanosized Résumé : Nano sized copper chromite, which is used as a burn rate accelerator for solid propellants, was synthesized by the solution combustion process using citric acid and glycine as fuel. Pure spinel phase copper chromite (CuCr2O4) was synthesized, and the effect of different ratios of Cu–Cr ions in the initial reactant and various calcination temperatures on the final properties of the material were examined. The reaction time for the synthesis with glycine was lower compared to that with citric acid. The synthesized samples from both fuel cycles were characterized by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), BET surface area analysis, and scanning electron microscope (SEM). Commercial copper chromite that is currently used in solid propellant formulation was also characterized by the same techniques. XRD analysis shows that the pure spinel phase compound is formed by calcination at 700 °C for glycine fuel cycle and between 750 and 800 °C for citric acid cycle. XPS results indicate the variation of the oxidation state of copper in the final compound with a change in the Cu–Cr mole ratio. SEM images confirm the formation of nano size spherical shape particles. The variation of BET surface area with calcination temperature was studied for the solution combusted catalyst. Burn rate evaluation of synthesized catalyst was carried out and compared with the commercial catalyst. The comparison between BET surface area and the burn rate depicts that surface area difference caused the variation in burn rate between samples. The reason behind the reduction in surface area and the required modifications in the process are also described. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie301435r Exemplaires
Code-barres Cote Support Localisation Section Disponibilité aucun exemplaire
Titre : Characterization of fluoropolymer nanofiber sheets fabricated by CO2 laser drawing without solvents Type de document : texte imprimé Auteurs : Kei Fukuhara, Auteur ; Takemune Yamada, Auteur ; Akihiro Suzuki, Auteur Année de publication : 2012 Article en page(s) : pp. 10117–10123 Note générale : Industrial chemistry Langues : Anglais (eng) Mots-clés : Nanofiber Fluoropolymer Résumé : Nanofibers of tetrafluoroethylene-perfluoroalkyl vinylether (PFA) copolymer were prepared by irradiating PFA fibers with a CO2 laser under supersonic velocities. This is the only method to make PFA nanofibers without the use of solvents, because for the majority of methods for preparing nanofibers, they must be dissolved in a solvent and PFA fibers cannot be dissolved in most solvents, except special fluorinating reagents. The average fiber diameter of PFA nanofibers was approximately 273 nm. As a result, we developed a CO2 laser supersonic multidrawing (CLSMD) in a new way to produce PFA nanofibers in large quantities. CLSMD can make nanofibers continually in a wide area. The length, width, and thickness of pileup nanofiber sheets are 50 cm, 17 cm, and 70 μm, respectively. It was observed that nanofiber sheets have a higher melting point and degree of crystallinity than microfibers by differential scanning calorimetry (DSC) measurements and have larger crystallite size realized by wide-angle X-ray diffraction (WAXD) measurements. Moreover, it was considered that the interior of nanofiber sheets have oriented structurally and the strength of nanofiber sheets was higher than that of microfibers. Nanoparticles were evolved to the surface of nanofiber sheets by annealing. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie301138t
in Industrial & engineering chemistry research > Vol. 51 N° 30 (Août 2012) . - pp. 10117–10123[article] Characterization of fluoropolymer nanofiber sheets fabricated by CO2 laser drawing without solvents [texte imprimé] / Kei Fukuhara, Auteur ; Takemune Yamada, Auteur ; Akihiro Suzuki, Auteur . - 2012 . - pp. 10117–10123.
Industrial chemistry
Langues : Anglais (eng)
in Industrial & engineering chemistry research > Vol. 51 N° 30 (Août 2012) . - pp. 10117–10123
Mots-clés : Nanofiber Fluoropolymer Résumé : Nanofibers of tetrafluoroethylene-perfluoroalkyl vinylether (PFA) copolymer were prepared by irradiating PFA fibers with a CO2 laser under supersonic velocities. This is the only method to make PFA nanofibers without the use of solvents, because for the majority of methods for preparing nanofibers, they must be dissolved in a solvent and PFA fibers cannot be dissolved in most solvents, except special fluorinating reagents. The average fiber diameter of PFA nanofibers was approximately 273 nm. As a result, we developed a CO2 laser supersonic multidrawing (CLSMD) in a new way to produce PFA nanofibers in large quantities. CLSMD can make nanofibers continually in a wide area. The length, width, and thickness of pileup nanofiber sheets are 50 cm, 17 cm, and 70 μm, respectively. It was observed that nanofiber sheets have a higher melting point and degree of crystallinity than microfibers by differential scanning calorimetry (DSC) measurements and have larger crystallite size realized by wide-angle X-ray diffraction (WAXD) measurements. Moreover, it was considered that the interior of nanofiber sheets have oriented structurally and the strength of nanofiber sheets was higher than that of microfibers. Nanoparticles were evolved to the surface of nanofiber sheets by annealing. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie301138t Exemplaires
Code-barres Cote Support Localisation Section Disponibilité aucun exemplaire
Titre : Large eddy simulation of turbulent flow and mixing time in a gas – liquid stirred tank Type de document : texte imprimé Auteurs : Qinghua Zhang, Auteur ; Chao Yang, Auteur ; Zai-Sha Mao, Auteur Année de publication : 2012 Article en page(s) : pp. 10124-10131 Note générale : Industrial chemistry Langues : Anglais (eng) Mots-clés : Stirred vessel Mixing time Turbulent flow Large eddy simulation Résumé : Mixing time is a key parameter relevant to the scale-up and design of agitated reactors. Although there have been many published papers on mixing times in stirred tanks predicted by computational fluid dynamics (CFD), there are few reports on the large eddy simulation (LES) based prediction of the mixing time in a gas―liquid stirred tank. In this work, an LES method based on an Eulerian―Eulerian model is presented for predicting the mixing time in a gas―liquid stirred tank agitated by a Rushton turbine. In order to verify the simulated results, mixing time experiments were carried out using a conductivity technique. In the present LES, the Smagorinsky subgrid scale model was used to model the effect of subgrid scale on the resolved scales. The concentration distributions and operating parameters such as feed positions, impeller speeds, and gas flow rates on the mixing time were examined It is shown that the predicted concentration distributions of tracers are more irregular and realistic by using LES. Also, the mixing time decreases with the increase of impeller speed. However, with increasing gas flow rate, the mixing time first increases and then levels off. The predicted mixing time by the LES method shows good agreement with the measured values. ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=26201427
in Industrial & engineering chemistry research > Vol. 51 N° 30 (Août 2012) . - pp. 10124-10131[article] Large eddy simulation of turbulent flow and mixing time in a gas – liquid stirred tank [texte imprimé] / Qinghua Zhang, Auteur ; Chao Yang, Auteur ; Zai-Sha Mao, Auteur . - 2012 . - pp. 10124-10131.
Industrial chemistry
Langues : Anglais (eng)
in Industrial & engineering chemistry research > Vol. 51 N° 30 (Août 2012) . - pp. 10124-10131
Mots-clés : Stirred vessel Mixing time Turbulent flow Large eddy simulation Résumé : Mixing time is a key parameter relevant to the scale-up and design of agitated reactors. Although there have been many published papers on mixing times in stirred tanks predicted by computational fluid dynamics (CFD), there are few reports on the large eddy simulation (LES) based prediction of the mixing time in a gas―liquid stirred tank. In this work, an LES method based on an Eulerian―Eulerian model is presented for predicting the mixing time in a gas―liquid stirred tank agitated by a Rushton turbine. In order to verify the simulated results, mixing time experiments were carried out using a conductivity technique. In the present LES, the Smagorinsky subgrid scale model was used to model the effect of subgrid scale on the resolved scales. The concentration distributions and operating parameters such as feed positions, impeller speeds, and gas flow rates on the mixing time were examined It is shown that the predicted concentration distributions of tracers are more irregular and realistic by using LES. Also, the mixing time decreases with the increase of impeller speed. However, with increasing gas flow rate, the mixing time first increases and then levels off. The predicted mixing time by the LES method shows good agreement with the measured values. ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=26201427 Exemplaires
Code-barres Cote Support Localisation Section Disponibilité aucun exemplaire
Titre : Effect of inlet flow distributor for reagent equalization on autothermal reforming of ethanol in a microreformer Type de document : texte imprimé Auteurs : Hongqing Chen, Auteur ; Hao Yu, Auteur ; Jichao Li, Auteur Année de publication : 2012 Article en page(s) : pp. 10132-10139 Note générale : Industrial chemistry Langues : Anglais (eng) Mots-clés : Autothermic reactor Reforming Résumé : Two types of flow distributors, that is, a jet-flow-splitter and a simplified constructal distributor, were designed to equalize the gaseous reagents in the inlet of a microreformer packed with catalyst supported on ceramic foam. The effects of type and geometry of distributors on flow, temperature distributions, and reaction performance over the catalyst during the autothermal reforming of ethanol were investigated experimentally and computationally. It was found that the jet flow splitter in the shape of cone or hemisphere can effectively equalize the flow distribution on the lower surface of catalyst, thereby improving the temperature distribution and performance of the microreformer. A microreformer with a hemisphere jet-flow-splitter in optimal geometry can convert 91% of ethanol with a selectivity to hydrogen of 74%, equivalent to yielding 3.3 mol of hydrogen per mol ethanol. Such a distribution device can be used to fabricate an efficient microreformer with simple structure for the hydrogen production orienting the portable fuel cell application. ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=26201428
in Industrial & engineering chemistry research > Vol. 51 N° 30 (Août 2012) . - pp. 10132-10139[article] Effect of inlet flow distributor for reagent equalization on autothermal reforming of ethanol in a microreformer [texte imprimé] / Hongqing Chen, Auteur ; Hao Yu, Auteur ; Jichao Li, Auteur . - 2012 . - pp. 10132-10139.
Industrial chemistry
Langues : Anglais (eng)
in Industrial & engineering chemistry research > Vol. 51 N° 30 (Août 2012) . - pp. 10132-10139
Mots-clés : Autothermic reactor Reforming Résumé : Two types of flow distributors, that is, a jet-flow-splitter and a simplified constructal distributor, were designed to equalize the gaseous reagents in the inlet of a microreformer packed with catalyst supported on ceramic foam. The effects of type and geometry of distributors on flow, temperature distributions, and reaction performance over the catalyst during the autothermal reforming of ethanol were investigated experimentally and computationally. It was found that the jet flow splitter in the shape of cone or hemisphere can effectively equalize the flow distribution on the lower surface of catalyst, thereby improving the temperature distribution and performance of the microreformer. A microreformer with a hemisphere jet-flow-splitter in optimal geometry can convert 91% of ethanol with a selectivity to hydrogen of 74%, equivalent to yielding 3.3 mol of hydrogen per mol ethanol. Such a distribution device can be used to fabricate an efficient microreformer with simple structure for the hydrogen production orienting the portable fuel cell application. ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=26201428 Exemplaires
Code-barres Cote Support Localisation Section Disponibilité aucun exemplaire
Titre : Biomimetic synthesis of magnetic composite particles for laccase immobilization Type de document : texte imprimé Auteurs : Xiaobing Zheng, Auteur ; Qi Wang, Auteur ; Yanjun Jiang, Auteur Année de publication : 2012 Article en page(s) : pp. 10140–10146 Note générale : Industrial chemistry Langues : Anglais (eng) Mots-clés : Biomimetic Magnetic composite Résumé : Magnetic silica composite particles were prepared by using the biosilicification reaction, in which Fe3O4 nanoparticles were entrapped in a silica matrix. The composite particles were functionalized with 3-aminopropyltriethoxysilane (APTES). These functionalized magnetic composite particles were used to immobilize a kind of valuable bulky industrial enzyme (laccase). The incorporation of magnetic nanoparticles greatly facilitates the manipulation of the immobilized biocatalyst, since it can be easily and quickly recovered from the reaction system by the simple application of an external magnetic field. The effects of immobilization conditions were optimized and the activity of the immobilized laccase was investigated. The results showed that the highest specific activity of immobilized laccase reached to 224 U and the activity recovery was 83.9%. Compared with free laccase, the thermal, pH, operational and storage stabilities of the immobilized laccase were improved significantly. The catalytic activity of the immobilized laccase was also demonstrated by the degradation of two phenolic substances (i.e., 2,4-dichlorophenol and 4-chlorophenol). It was found that the removal rates of 2,4-dichlorophenol and 4-chlorophenol were 80.9% and 64.2% in about 12 h, respectively. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie3000908
in Industrial & engineering chemistry research > Vol. 51 N° 30 (Août 2012) . - pp. 10140–10146[article] Biomimetic synthesis of magnetic composite particles for laccase immobilization [texte imprimé] / Xiaobing Zheng, Auteur ; Qi Wang, Auteur ; Yanjun Jiang, Auteur . - 2012 . - pp. 10140–10146.
Industrial chemistry
Langues : Anglais (eng)
in Industrial & engineering chemistry research > Vol. 51 N° 30 (Août 2012) . - pp. 10140–10146
Mots-clés : Biomimetic Magnetic composite Résumé : Magnetic silica composite particles were prepared by using the biosilicification reaction, in which Fe3O4 nanoparticles were entrapped in a silica matrix. The composite particles were functionalized with 3-aminopropyltriethoxysilane (APTES). These functionalized magnetic composite particles were used to immobilize a kind of valuable bulky industrial enzyme (laccase). The incorporation of magnetic nanoparticles greatly facilitates the manipulation of the immobilized biocatalyst, since it can be easily and quickly recovered from the reaction system by the simple application of an external magnetic field. The effects of immobilization conditions were optimized and the activity of the immobilized laccase was investigated. The results showed that the highest specific activity of immobilized laccase reached to 224 U and the activity recovery was 83.9%. Compared with free laccase, the thermal, pH, operational and storage stabilities of the immobilized laccase were improved significantly. The catalytic activity of the immobilized laccase was also demonstrated by the degradation of two phenolic substances (i.e., 2,4-dichlorophenol and 4-chlorophenol). It was found that the removal rates of 2,4-dichlorophenol and 4-chlorophenol were 80.9% and 64.2% in about 12 h, respectively. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie3000908 Exemplaires
Code-barres Cote Support Localisation Section Disponibilité aucun exemplaire
Titre : Prediction of water percolation threshold of a microemulsion uising electrical conductivity measurements and design of experiments Type de document : texte imprimé Auteurs : Zahra Jeirani, Auteur ; Badrul Mohamed Jan, Auteur ; Brahim Si Ali, Auteur Année de publication : 2012 Article en page(s) : pp. 10147-10155 Note générale : Industrial chemistry Langues : Anglais (eng) Mots-clés : Experimental design Electrical conductivity Microemulsion Prédiction Résumé : This paper presents the estimation of water percolation threshold (φc) of a nonionic microemulsion by studying its conductivity (σ) as a function of water volume fraction (φ). The initial solution of alkyl polyglycosides/glyceryl monooleate/ n-octane/isopropyl alcohol with weight ratios of 3/3/2/2 was diluted by brine (1 wt % sodium chroride), and the electrical conductance was measured along the specific dilution line. One factor design (OFD), which is an approach embedded in Design of Experiments (DOE), was used to model the variation of d(logσ)/dφ with φ. A quadratic equation with natural logarithm transformation was then fitted and validated. The model was optimized to predict φc, the water volume fraction at which d(logσ)/dφ is a maximum. The predicted value of φc from the optimization of the model is 0.1245. In addition, fitting to the scaling law was conducted, and the value of φc from this theoretical model was 0.1212. Apparently, these values are in excellent agreement It is concluded that DOE can be used to estimate the value of φc for a microemulsion relatively precisely with less computation and restriction compared to the conventional fitting approach. ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=26201430
in Industrial & engineering chemistry research > Vol. 51 N° 30 (Août 2012) . - pp. 10147-10155[article] Prediction of water percolation threshold of a microemulsion uising electrical conductivity measurements and design of experiments [texte imprimé] / Zahra Jeirani, Auteur ; Badrul Mohamed Jan, Auteur ; Brahim Si Ali, Auteur . - 2012 . - pp. 10147-10155.
Industrial chemistry
Langues : Anglais (eng)
in Industrial & engineering chemistry research > Vol. 51 N° 30 (Août 2012) . - pp. 10147-10155
Mots-clés : Experimental design Electrical conductivity Microemulsion Prédiction Résumé : This paper presents the estimation of water percolation threshold (φc) of a nonionic microemulsion by studying its conductivity (σ) as a function of water volume fraction (φ). The initial solution of alkyl polyglycosides/glyceryl monooleate/ n-octane/isopropyl alcohol with weight ratios of 3/3/2/2 was diluted by brine (1 wt % sodium chroride), and the electrical conductance was measured along the specific dilution line. One factor design (OFD), which is an approach embedded in Design of Experiments (DOE), was used to model the variation of d(logσ)/dφ with φ. A quadratic equation with natural logarithm transformation was then fitted and validated. The model was optimized to predict φc, the water volume fraction at which d(logσ)/dφ is a maximum. The predicted value of φc from the optimization of the model is 0.1245. In addition, fitting to the scaling law was conducted, and the value of φc from this theoretical model was 0.1212. Apparently, these values are in excellent agreement It is concluded that DOE can be used to estimate the value of φc for a microemulsion relatively precisely with less computation and restriction compared to the conventional fitting approach. ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=26201430 Exemplaires
Code-barres Cote Support Localisation Section Disponibilité aucun exemplaire
Titre : Affinity between metal – organic frameworks and polyimides in asymmetric mixed matrix membranes for gas separations Type de document : texte imprimé Auteurs : Huiqing Ren, Auteur ; Jiaying Jin, Auteur ; Jun Hu, Auteur Année de publication : 2012 Article en page(s) : pp. 10156-10164 Note générale : Industrial chemistry Langues : Anglais (eng) Mots-clés : Affinity Résumé : A series of flat-sheet asymmetric mixed matrix membranes (MMMs) have been fabricated with MOF-5, Cu3(BTC)2, and MIL 53(Al) as fillers and PI polymer as a matrix through the dry―wet phase inversion method. After the surface modification by coating a PAA solution (15% wt) on the top of the obtained membrane, a thin defect-free selective skin in the MMM is obtained. The permeance of various gases such as H2, He, CH4, N2, and CO2 and their gas pair selectivity have been investigated, respectively. The results show that Cu3(BTC)2/PI MMM possesses the best gas separation performance with H2 permeance of 0.44 GPU and H2/CH, selectivity of 100. In addition, the mechanism of MOF fillers in MMMs has been further revealed by the interaction analysis between MOF fillers and PI chains. ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=26201431
in Industrial & engineering chemistry research > Vol. 51 N° 30 (Août 2012) . - pp. 10156-10164[article] Affinity between metal – organic frameworks and polyimides in asymmetric mixed matrix membranes for gas separations [texte imprimé] / Huiqing Ren, Auteur ; Jiaying Jin, Auteur ; Jun Hu, Auteur . - 2012 . - pp. 10156-10164.
Industrial chemistry
Langues : Anglais (eng)
in Industrial & engineering chemistry research > Vol. 51 N° 30 (Août 2012) . - pp. 10156-10164
Mots-clés : Affinity Résumé : A series of flat-sheet asymmetric mixed matrix membranes (MMMs) have been fabricated with MOF-5, Cu3(BTC)2, and MIL 53(Al) as fillers and PI polymer as a matrix through the dry―wet phase inversion method. After the surface modification by coating a PAA solution (15% wt) on the top of the obtained membrane, a thin defect-free selective skin in the MMM is obtained. The permeance of various gases such as H2, He, CH4, N2, and CO2 and their gas pair selectivity have been investigated, respectively. The results show that Cu3(BTC)2/PI MMM possesses the best gas separation performance with H2 permeance of 0.44 GPU and H2/CH, selectivity of 100. In addition, the mechanism of MOF fillers in MMMs has been further revealed by the interaction analysis between MOF fillers and PI chains. ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=26201431 Exemplaires
Code-barres Cote Support Localisation Section Disponibilité aucun exemplaire
Titre : Measurement of Voidage of Sinter Ores in the Tubes Type de document : texte imprimé Auteurs : Penggang Zhang, Auteur ; Jiuju Cai, Auteur ; Hui Dong, Auteur Année de publication : 2012 Article en page(s) : pp. 10165-10171 Note générale : Industrial chemistry Langues : Anglais (eng) Mots-clés : Measurement Sinter Ores Tubes Résumé : An industrial vertical tank (cost $200,000) was produced to recover the heat of sinter ores in our laboratory, the voidage along the height direction needs to be studied in order to determine the best height of sintering layer in it. In this paper, the bulk bed voidage of sinter ores in cylindrical polyvinylchloride tube (PVC-U) was measured by the cross-section image analysis method. The large-diameter tube was used to minimize the wall effects so that we could measure the bulk bed voidage in the center of the tube. The results show that the new method is useful, the voidage increases at lower height and fluctuates slightly between 0.36 and 0.43 in a stable stage, the voidage increases as particle size increases, decreases as the shape factor increases, and increases as the tube to particle diameter ratios decreases. These provide significant voidage data for the study of a vertical tank. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie300801e
in Industrial & engineering chemistry research > Vol. 51 N° 30 (Août 2012) . - pp. 10165-10171[article] Measurement of Voidage of Sinter Ores in the Tubes [texte imprimé] / Penggang Zhang, Auteur ; Jiuju Cai, Auteur ; Hui Dong, Auteur . - 2012 . - pp. 10165-10171.
Industrial chemistry
Langues : Anglais (eng)
in Industrial & engineering chemistry research > Vol. 51 N° 30 (Août 2012) . - pp. 10165-10171
Mots-clés : Measurement Sinter Ores Tubes Résumé : An industrial vertical tank (cost $200,000) was produced to recover the heat of sinter ores in our laboratory, the voidage along the height direction needs to be studied in order to determine the best height of sintering layer in it. In this paper, the bulk bed voidage of sinter ores in cylindrical polyvinylchloride tube (PVC-U) was measured by the cross-section image analysis method. The large-diameter tube was used to minimize the wall effects so that we could measure the bulk bed voidage in the center of the tube. The results show that the new method is useful, the voidage increases at lower height and fluctuates slightly between 0.36 and 0.43 in a stable stage, the voidage increases as particle size increases, decreases as the shape factor increases, and increases as the tube to particle diameter ratios decreases. These provide significant voidage data for the study of a vertical tank. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie300801e Exemplaires
Code-barres Cote Support Localisation Section Disponibilité aucun exemplaire
Titre : Wetting of PTFE and glass surfaces by aqueous solutions of cationic and anionic double - chain surfactants Type de document : texte imprimé Auteurs : Nihar Ranjan Biswal, Auteur ; Santanu Paria, Auteur Année de publication : 2012 Article en page(s) : pp. 10172–10178 Note générale : Industrial chemistry Langues : Anglais (eng) Mots-clés : Wetting Glass Aqueous solutions Cationic Anionic Résumé : The wetting of hydrophobic and hydrophilic solid surfaces by surfactant solutions is an important research topic recently because of its profound practical applications. The wettability of two double-chain surfactants (cationic, didodecyldimethylammonium bromide or DDAB, and anionic, aerosol OT or AOT) solutions on poly(tetrafluoroethylene) (PTFE) and glass surfaces has been investigated here. Different physicochemical parameters such as critical micelle concentration (CMC) and surface tension, contact angle, surface excess at air–water and solid-water interfaces, work of adhesion, and free energy of wetting have been estimated for two double-chain surfactants solutions and compared with the reported results of single-chain surfactants. The double-chain surfactant solutions showed maximum lowering of surface tension values (24.36 and 26.35 mN/m for DDAB and AOT, respectively) and a change in contact angle values from pure water on PTFE (38° for DDAB and AOT) and glass (26.5 and 24° for DDAB and AOT, respectively) surfaces compared to the conventionally studied single-chain surfactants. The surfactant molecules mostly formed a monolayer adsorption on both surfaces during the wetting process. The surface excess values of both of the surfactants on PTFE–water and glass–water interfaces are 0.759 and 0.850 times lower than that of the air–water interface, respectively. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie301198k
in Industrial & engineering chemistry research > Vol. 51 N° 30 (Août 2012) . - pp. 10172–10178[article] Wetting of PTFE and glass surfaces by aqueous solutions of cationic and anionic double - chain surfactants [texte imprimé] / Nihar Ranjan Biswal, Auteur ; Santanu Paria, Auteur . - 2012 . - pp. 10172–10178.
Industrial chemistry
Langues : Anglais (eng)
in Industrial & engineering chemistry research > Vol. 51 N° 30 (Août 2012) . - pp. 10172–10178
Mots-clés : Wetting Glass Aqueous solutions Cationic Anionic Résumé : The wetting of hydrophobic and hydrophilic solid surfaces by surfactant solutions is an important research topic recently because of its profound practical applications. The wettability of two double-chain surfactants (cationic, didodecyldimethylammonium bromide or DDAB, and anionic, aerosol OT or AOT) solutions on poly(tetrafluoroethylene) (PTFE) and glass surfaces has been investigated here. Different physicochemical parameters such as critical micelle concentration (CMC) and surface tension, contact angle, surface excess at air–water and solid-water interfaces, work of adhesion, and free energy of wetting have been estimated for two double-chain surfactants solutions and compared with the reported results of single-chain surfactants. The double-chain surfactant solutions showed maximum lowering of surface tension values (24.36 and 26.35 mN/m for DDAB and AOT, respectively) and a change in contact angle values from pure water on PTFE (38° for DDAB and AOT) and glass (26.5 and 24° for DDAB and AOT, respectively) surfaces compared to the conventionally studied single-chain surfactants. The surfactant molecules mostly formed a monolayer adsorption on both surfaces during the wetting process. The surface excess values of both of the surfactants on PTFE–water and glass–water interfaces are 0.759 and 0.850 times lower than that of the air–water interface, respectively. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie301198k Exemplaires
Code-barres Cote Support Localisation Section Disponibilité aucun exemplaire
Titre : Selection of controlled variables for a natural gas to liquids process Type de document : texte imprimé Auteurs : Mehdi Panahi, Auteur ; Sigurd Skogestad, Auteur Année de publication : 2012 Article en page(s) : pp. 10179-10190 Note générale : Industrial chmistry Langues : Anglais (eng) Mots-clés : Natural gas Résumé : The aim of this work is to select the best individual or combined controlled variables (CVs) for a natural gas to hydrocarbon liquids (GTL) process based on the idea of self-optimizing control. The objective function is to maximize the variable income of the plant, and two modes of operation are studied. In mode I, where the natural gas flow rate is given, there are three unconstrained degrees of freedom (DOFs) and the corresponding individual self-optimizing CVs are selected as (i) CO2 removal in fresh synthesis gas (syngas), (ii) CO mole fraction in fresh syngas, and (iii) CO mole fraction in recycle tail gas from the Fischer—Tropsch (FT) reactor. This set of CVs gives a worst-case loss of 1,393 USD/h. Adding one, two, and three measurements and controlling measurement combinations decrease the worst-case loss significantly, to 184, 161, and 53 USD/h, respectively. In mode II, the natural gas flow rate is a degree of freedom and it is optimal to increase it as much as possible to maximize profit. The variable income increases almost linearly until the oxygen flow rate becomes active. Practically, this is the maximum achievable income. Theoretically, it is possible to increase the natural gas flow rate to improve the objective function, but this results in large recycle flow rates to the FT reactor (similar to "snowballing") because its volume is the limitation. ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=26201434
in Industrial & engineering chemistry research > Vol. 51 N° 30 (Août 2012) . - pp. 10179-10190[article] Selection of controlled variables for a natural gas to liquids process [texte imprimé] / Mehdi Panahi, Auteur ; Sigurd Skogestad, Auteur . - 2012 . - pp. 10179-10190.
Industrial chmistry
Langues : Anglais (eng)
in Industrial & engineering chemistry research > Vol. 51 N° 30 (Août 2012) . - pp. 10179-10190
Mots-clés : Natural gas Résumé : The aim of this work is to select the best individual or combined controlled variables (CVs) for a natural gas to hydrocarbon liquids (GTL) process based on the idea of self-optimizing control. The objective function is to maximize the variable income of the plant, and two modes of operation are studied. In mode I, where the natural gas flow rate is given, there are three unconstrained degrees of freedom (DOFs) and the corresponding individual self-optimizing CVs are selected as (i) CO2 removal in fresh synthesis gas (syngas), (ii) CO mole fraction in fresh syngas, and (iii) CO mole fraction in recycle tail gas from the Fischer—Tropsch (FT) reactor. This set of CVs gives a worst-case loss of 1,393 USD/h. Adding one, two, and three measurements and controlling measurement combinations decrease the worst-case loss significantly, to 184, 161, and 53 USD/h, respectively. In mode II, the natural gas flow rate is a degree of freedom and it is optimal to increase it as much as possible to maximize profit. The variable income increases almost linearly until the oxygen flow rate becomes active. Practically, this is the maximum achievable income. Theoretically, it is possible to increase the natural gas flow rate to improve the objective function, but this results in large recycle flow rates to the FT reactor (similar to "snowballing") because its volume is the limitation. ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=26201434 Exemplaires
Code-barres Cote Support Localisation Section Disponibilité aucun exemplaire
Titre : Optimization of procurement and production planning model in refinery processes considering corrosion effect Type de document : texte imprimé Auteurs : Junghwan Kim, Auteur ; Kyungjae Tak, Auteur ; Il Moon, Auteur Année de publication : 2012 Article en page(s) : pp. 10191-10200 Note générale : Industrial chemistry Langues : Anglais (eng) Mots-clés : Corrosion Refinery Modeling Production planning Optimization Résumé : This study focused on finding optimal procurement and production planning including corrosion effect. We developed the corrosion forecasting and cost model, which are combined in the procurement and production planning model. The corrosion cost model was presented to calculate cost depending on corrosion rate estimated by corrosion factors, which are H+, Cl―, H2S, and CO2. This study found the optimal results such as the optimal amount of crude to be purchased and optimal design. Several case studies are also included in this study to analyze and improve the optimization production planning model of petrochemical and refinery processes. Although the government regulation requires the operating cycle time as 4 years, this study reveals that the profit per day is increasing up to 5 years if the corrosion is considered. This result increases the net profit per day about 4.14% in a crude distillation unit (CDU) process with 120000 barrels per day capacity. ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=26201435
in Industrial & engineering chemistry research > Vol. 51 N° 30 (Août 2012) . - pp. 10191-10200[article] Optimization of procurement and production planning model in refinery processes considering corrosion effect [texte imprimé] / Junghwan Kim, Auteur ; Kyungjae Tak, Auteur ; Il Moon, Auteur . - 2012 . - pp. 10191-10200.
Industrial chemistry
Langues : Anglais (eng)
in Industrial & engineering chemistry research > Vol. 51 N° 30 (Août 2012) . - pp. 10191-10200
Mots-clés : Corrosion Refinery Modeling Production planning Optimization Résumé : This study focused on finding optimal procurement and production planning including corrosion effect. We developed the corrosion forecasting and cost model, which are combined in the procurement and production planning model. The corrosion cost model was presented to calculate cost depending on corrosion rate estimated by corrosion factors, which are H+, Cl―, H2S, and CO2. This study found the optimal results such as the optimal amount of crude to be purchased and optimal design. Several case studies are also included in this study to analyze and improve the optimization production planning model of petrochemical and refinery processes. Although the government regulation requires the operating cycle time as 4 years, this study reveals that the profit per day is increasing up to 5 years if the corrosion is considered. This result increases the net profit per day about 4.14% in a crude distillation unit (CDU) process with 120000 barrels per day capacity. ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=26201435 Exemplaires
Code-barres Cote Support Localisation Section Disponibilité aucun exemplaire
Titre : Product separation after chemical interesterification of vegetable oils with methyl acetate. Part II : Liquid – liquid equilibrium Type de document : texte imprimé Auteurs : Abraham Casas, Auteur ; Maria Jesús Ramos, Auteur ; Angel Pérez, Auteur Année de publication : 2012 Article en page(s) : pp. 10201–10206 Note générale : Industrial chemistry Langues : Anglais (eng) Mots-clés : Vegetable Oils Liquid equilibrium Résumé : The aim of this work was the removal of diacetin, monoacetin, and glycerol from biodiesel–triacetin mixtures using liquid–liquid extraction with water. Liquid–liquid equilibrium was predicted using UNIFAC based models for the activity coefficient calculations. These data have been corroborated with experimental information from all possible binary, ternary (water, triacetin, and biodiesel), and overall (diacetin, monoacetin, glycerol, water, triacetin, and biodiesel) mixtures. The experimental determination of the diacetin, monoacetin, and glycerol distribution factor and their selectivity with respect to triacetin allows the operating temperature set at 27.5 °C. After that, it was determined that three washing steps, with a water to feed mixture mass ratio of 0.05 (per stage), were necessary for the effective elimination of these compounds. The final composition of the raffinate phase was 94.6 wt % biodiesel and 5.1 wt % triacetin. The extract phase consisted of a mixture of 59.2 wt % acetins and glycerol and 40.7 wt % water. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie300791g
in Industrial & engineering chemistry research > Vol. 51 N° 30 (Août 2012) . - pp. 10201–10206[article] Product separation after chemical interesterification of vegetable oils with methyl acetate. Part II : Liquid – liquid equilibrium [texte imprimé] / Abraham Casas, Auteur ; Maria Jesús Ramos, Auteur ; Angel Pérez, Auteur . - 2012 . - pp. 10201–10206.
Industrial chemistry
Langues : Anglais (eng)
in Industrial & engineering chemistry research > Vol. 51 N° 30 (Août 2012) . - pp. 10201–10206
Mots-clés : Vegetable Oils Liquid equilibrium Résumé : The aim of this work was the removal of diacetin, monoacetin, and glycerol from biodiesel–triacetin mixtures using liquid–liquid extraction with water. Liquid–liquid equilibrium was predicted using UNIFAC based models for the activity coefficient calculations. These data have been corroborated with experimental information from all possible binary, ternary (water, triacetin, and biodiesel), and overall (diacetin, monoacetin, glycerol, water, triacetin, and biodiesel) mixtures. The experimental determination of the diacetin, monoacetin, and glycerol distribution factor and their selectivity with respect to triacetin allows the operating temperature set at 27.5 °C. After that, it was determined that three washing steps, with a water to feed mixture mass ratio of 0.05 (per stage), were necessary for the effective elimination of these compounds. The final composition of the raffinate phase was 94.6 wt % biodiesel and 5.1 wt % triacetin. The extract phase consisted of a mixture of 59.2 wt % acetins and glycerol and 40.7 wt % water. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie300791g Exemplaires
Code-barres Cote Support Localisation Section Disponibilité aucun exemplaire
Titre : Integrated membrane processes for separation and purification of organic acid from a biomass fermentation process Type de document : texte imprimé Auteurs : Young Hoon Cho, Auteur ; Hee Dae Lee, Auteur ; Ho Bum Park, Auteur Année de publication : 2012 Article en page(s) : pp. 10207-10219 Note générale : Industrial chemistry Langues : Anglais (eng) Mots-clés : Fermentation Biomass Purification Résumé : During biomass (e.g., waste wood chips) decomposition under an anaerobic fermentation process, organic acids such as acetic acid and butyric acid are continuously produced from controlled microbial activity. Since the accumulation of organic acids hinders the microbial metabolism in the fermentation broths, the organic acids should be removed by using appropriate separation processes. A few separation processes such as extraction, electrodialysis, and distillation have been reported, but they still have many limitations such as high energy input and environmental problems (e.g., toxic chemical effluents). The integrated membrane processes proposed here, including the three steps of ( 1 ) clarification of fermentation broth, (2) organic acid separation, and (3) dewatering, can be applied to achieve energy-efficient and environmentally friendly organic acid removal and recovery. First, microorganisms and large insoluble particles in fermentation feed can be mostly removed by clarification steps using microfiltration or ultrafiltration processes. In this study, we focused only on organic acid separation and dewatering processes using nanofiltration and forward osmosis membrane processes. Using nanofiltration (or high-flux reverse osmosis) membranes, aqueous organic acids can be selectively separated from pretreated fermentation feed solutions while other organics and many salts can be rejected using these processes by varying pH conditions in the feed. Finally, a low-energy-consuming forward osmosis process was applied for dewatering in the aqueous organic acid solutions to concentrate organic add. The concentrated organic acid was successfully obtained by using conventional desalination and/or commercial forward osmosis membranes. ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=26201437
in Industrial & engineering chemistry research > Vol. 51 N° 30 (Août 2012) . - pp. 10207-10219[article] Integrated membrane processes for separation and purification of organic acid from a biomass fermentation process [texte imprimé] / Young Hoon Cho, Auteur ; Hee Dae Lee, Auteur ; Ho Bum Park, Auteur . - 2012 . - pp. 10207-10219.
Industrial chemistry
Langues : Anglais (eng)
in Industrial & engineering chemistry research > Vol. 51 N° 30 (Août 2012) . - pp. 10207-10219
Mots-clés : Fermentation Biomass Purification Résumé : During biomass (e.g., waste wood chips) decomposition under an anaerobic fermentation process, organic acids such as acetic acid and butyric acid are continuously produced from controlled microbial activity. Since the accumulation of organic acids hinders the microbial metabolism in the fermentation broths, the organic acids should be removed by using appropriate separation processes. A few separation processes such as extraction, electrodialysis, and distillation have been reported, but they still have many limitations such as high energy input and environmental problems (e.g., toxic chemical effluents). The integrated membrane processes proposed here, including the three steps of ( 1 ) clarification of fermentation broth, (2) organic acid separation, and (3) dewatering, can be applied to achieve energy-efficient and environmentally friendly organic acid removal and recovery. First, microorganisms and large insoluble particles in fermentation feed can be mostly removed by clarification steps using microfiltration or ultrafiltration processes. In this study, we focused only on organic acid separation and dewatering processes using nanofiltration and forward osmosis membrane processes. Using nanofiltration (or high-flux reverse osmosis) membranes, aqueous organic acids can be selectively separated from pretreated fermentation feed solutions while other organics and many salts can be rejected using these processes by varying pH conditions in the feed. Finally, a low-energy-consuming forward osmosis process was applied for dewatering in the aqueous organic acid solutions to concentrate organic add. The concentrated organic acid was successfully obtained by using conventional desalination and/or commercial forward osmosis membranes. ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=26201437 Exemplaires
Code-barres Cote Support Localisation Section Disponibilité aucun exemplaire
Titre : A New target function for robust data reconciliation Type de document : texte imprimé Auteurs : Siyi Jin, Auteur ; Xuewen Li, Auteur ; Zhaojie Huang, Auteur Année de publication : 2012 Article en page(s) : pp. 10220-10224 Note générale : Industrial chemistry Langues : Anglais (eng) Mots-clés : Data reconciliation Résumé : To detect the gross errors efficiently in the process of data reconciliation, a new target function is proposed based on robust M-estimators. Robustness of this new target function is evaluated through the influence function. Then, the performance of the new target function is illustrated through a linear data reconciliation example and a nonlinear one. Simulation results show that the new target function gives promising results for data reconciliation and gross error detection. Besides, the proposed new target function has an advantage over the Cauchy and Huber functions on detecting small gross error. ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=26201438
in Industrial & engineering chemistry research > Vol. 51 N° 30 (Août 2012) . - pp. 10220-10224[article] A New target function for robust data reconciliation [texte imprimé] / Siyi Jin, Auteur ; Xuewen Li, Auteur ; Zhaojie Huang, Auteur . - 2012 . - pp. 10220-10224.
Industrial chemistry
Langues : Anglais (eng)
in Industrial & engineering chemistry research > Vol. 51 N° 30 (Août 2012) . - pp. 10220-10224
Mots-clés : Data reconciliation Résumé : To detect the gross errors efficiently in the process of data reconciliation, a new target function is proposed based on robust M-estimators. Robustness of this new target function is evaluated through the influence function. Then, the performance of the new target function is illustrated through a linear data reconciliation example and a nonlinear one. Simulation results show that the new target function gives promising results for data reconciliation and gross error detection. Besides, the proposed new target function has an advantage over the Cauchy and Huber functions on detecting small gross error. ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=26201438 Exemplaires
Code-barres Cote Support Localisation Section Disponibilité aucun exemplaire
Titre : Rheological transition during foam flow in porous media Type de document : texte imprimé Auteurs : M. Simjoo, Auteur ; Q. P. Nguyen, Auteur ; P. L. J. Zitha, Auteur Année de publication : 2012 Article en page(s) : pp. 10225-10231 Note générale : Industrial chemistry Langues : Anglais (eng) Mots-clés : Porous medium Foam Résumé : The flow of nitrogen foam in Bentheimer sandstone cores previously saturated with a surfactant solution has been investigated experimentally. The displacement process was visualized with the aid of a computed tomography (CT) scanner. CT data were analyzed to obtain water saturation profiles at different times. Pressure drops measured over core segments were recorded to determine foam mobility. It was found that foam undergoes a sharp transition from a weak to a strong state at a critical gas saturation of Sgc = 0.75 ± 0.02. This effect was interpreted successfully by the rise of foam yield stress as gas saturation exceeds the Sgc. It is suggested that confined jamming is the most likely mechanism responsible for the mobility transition. ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=26201439
in Industrial & engineering chemistry research > Vol. 51 N° 30 (Août 2012) . - pp. 10225-10231[article] Rheological transition during foam flow in porous media [texte imprimé] / M. Simjoo, Auteur ; Q. P. Nguyen, Auteur ; P. L. J. Zitha, Auteur . - 2012 . - pp. 10225-10231.
Industrial chemistry
Langues : Anglais (eng)
in Industrial & engineering chemistry research > Vol. 51 N° 30 (Août 2012) . - pp. 10225-10231
Mots-clés : Porous medium Foam Résumé : The flow of nitrogen foam in Bentheimer sandstone cores previously saturated with a surfactant solution has been investigated experimentally. The displacement process was visualized with the aid of a computed tomography (CT) scanner. CT data were analyzed to obtain water saturation profiles at different times. Pressure drops measured over core segments were recorded to determine foam mobility. It was found that foam undergoes a sharp transition from a weak to a strong state at a critical gas saturation of Sgc = 0.75 ± 0.02. This effect was interpreted successfully by the rise of foam yield stress as gas saturation exceeds the Sgc. It is suggested that confined jamming is the most likely mechanism responsible for the mobility transition. ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=26201439 Exemplaires
Code-barres Cote Support Localisation Section Disponibilité aucun exemplaire
Titre : Nematic - like alignment in SWNT thin films from aqueous colloidal suspensions Type de document : texte imprimé Auteurs : Budhadipta Dan, Auteur ; Anson W. K. Ma, Auteur ; Erik H. Haroz, Auteur Année de publication : 2012 Article en page(s) : pp. 10232-10237 Note générale : Industrial chemistry Langues : Anglais (eng) Mots-clés : Colloidal suspension Thin film Résumé : We present a modification of the vacuum filtration technique for fabricating transparent conductive SWNT thin films with local nematic-like orientational ordering. Dilute SWNT surfactant dispersions are filtered through a vacuum filtration setup in a slow and controlled fashion. The slow filtration creates a region of high SWNT concentration dose to the filter membrane. While slowly moving through this region, SWNTs interact and align with each other, resulting in the formation of thin films with local nematic ordering. Scanning electron microscopy and image analysis revealed a local scalar order parameter (S2D) of 0.7―0.8 for slow filtration, three times higher than those produced from "fast filtration" (S2D ≈ 0.24). Orientational ordering is demonstrated with different stabilizing surfactants, as well as with dispersions enriched in metallic SWNTs, produced by density-gradient ultracentrifugation. Simple estimates of relative convective versus diffusive transport highlight the main differences between slow versus fast filtration and the resulting SWNT concentration profiles. Comparisons with previous studies on three stages of liquid-crystal phase transition provide insight into the spontaneous ordering process, indicating the lack of a "healing stage", which results in a microstructure consisting of staggered domains in our SWNT films. ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=26201440
in Industrial & engineering chemistry research > Vol. 51 N° 30 (Août 2012) . - pp. 10232-10237[article] Nematic - like alignment in SWNT thin films from aqueous colloidal suspensions [texte imprimé] / Budhadipta Dan, Auteur ; Anson W. K. Ma, Auteur ; Erik H. Haroz, Auteur . - 2012 . - pp. 10232-10237.
Industrial chemistry
Langues : Anglais (eng)
in Industrial & engineering chemistry research > Vol. 51 N° 30 (Août 2012) . - pp. 10232-10237
Mots-clés : Colloidal suspension Thin film Résumé : We present a modification of the vacuum filtration technique for fabricating transparent conductive SWNT thin films with local nematic-like orientational ordering. Dilute SWNT surfactant dispersions are filtered through a vacuum filtration setup in a slow and controlled fashion. The slow filtration creates a region of high SWNT concentration dose to the filter membrane. While slowly moving through this region, SWNTs interact and align with each other, resulting in the formation of thin films with local nematic ordering. Scanning electron microscopy and image analysis revealed a local scalar order parameter (S2D) of 0.7―0.8 for slow filtration, three times higher than those produced from "fast filtration" (S2D ≈ 0.24). Orientational ordering is demonstrated with different stabilizing surfactants, as well as with dispersions enriched in metallic SWNTs, produced by density-gradient ultracentrifugation. Simple estimates of relative convective versus diffusive transport highlight the main differences between slow versus fast filtration and the resulting SWNT concentration profiles. Comparisons with previous studies on three stages of liquid-crystal phase transition provide insight into the spontaneous ordering process, indicating the lack of a "healing stage", which results in a microstructure consisting of staggered domains in our SWNT films. ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=26201440 Exemplaires
Code-barres Cote Support Localisation Section Disponibilité aucun exemplaire
Titre : Characteristics of deposits formed in cyclones in commercial RFCC reactor Type de document : texte imprimé Auteurs : Sung Won Kim, Auteur ; Ju Wook Lee, Auteur ; Cheol Joong Kim, Auteur Année de publication : 2012 Article en page(s) : pp. 10238-10246 Note générale : Industrial chemistry Langues : Anglais (eng) Mots-clés : Reactor Cyclone Résumé : Deposits in a commercial RFCC reactor were characterized using an analytical approach. Further characterization of deposits on the reactor cyclone, which are one of the primary problems causing abnormal shut-down of RFCC, was carried out in order to understand the formation mechanism of the deposit. The deposits in the reactor consist of hydrocarbon and inorganic matter, compositions of which are well matched with the RFCC catalyst. In a longitudinal analysis of a sample reflecting age, H/ C atomic ratio decreases slightly with increased aging time in inner regions and has high value at the surface region, which is a relatively fresh deposit. The particles, surrounded by carbonaceous matter, and amorphous carbonaceous matter are observed through surface micrographs. Aromatic compounds and nano- and microcatalyst fines contribute to the formation of deposits. Micro- and nanostructure of the deposit is amorphous or very weakly ordered. The H/C atomic ratios of samples with different ages, over 90 days, do not change with aging and are matched with a variation of feed API. Possible mechanisms for the deposit formation and its reducing methods are proposed. ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=26201441
in Industrial & engineering chemistry research > Vol. 51 N° 30 (Août 2012) . - pp. 10238-10246[article] Characteristics of deposits formed in cyclones in commercial RFCC reactor [texte imprimé] / Sung Won Kim, Auteur ; Ju Wook Lee, Auteur ; Cheol Joong Kim, Auteur . - 2012 . - pp. 10238-10246.
Industrial chemistry
Langues : Anglais (eng)
in Industrial & engineering chemistry research > Vol. 51 N° 30 (Août 2012) . - pp. 10238-10246
Mots-clés : Reactor Cyclone Résumé : Deposits in a commercial RFCC reactor were characterized using an analytical approach. Further characterization of deposits on the reactor cyclone, which are one of the primary problems causing abnormal shut-down of RFCC, was carried out in order to understand the formation mechanism of the deposit. The deposits in the reactor consist of hydrocarbon and inorganic matter, compositions of which are well matched with the RFCC catalyst. In a longitudinal analysis of a sample reflecting age, H/ C atomic ratio decreases slightly with increased aging time in inner regions and has high value at the surface region, which is a relatively fresh deposit. The particles, surrounded by carbonaceous matter, and amorphous carbonaceous matter are observed through surface micrographs. Aromatic compounds and nano- and microcatalyst fines contribute to the formation of deposits. Micro- and nanostructure of the deposit is amorphous or very weakly ordered. The H/C atomic ratios of samples with different ages, over 90 days, do not change with aging and are matched with a variation of feed API. Possible mechanisms for the deposit formation and its reducing methods are proposed. ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=26201441 Exemplaires
Code-barres Cote Support Localisation Section Disponibilité aucun exemplaire
Titre : Fick diffusion coefficients in ternary liquid systems from equilibrium molecular dynamics simulations Type de document : texte imprimé Auteurs : Xin Liu, Auteur ; Ana Martín-Calvo, Auteur ; Erin McGarrity, Auteur Année de publication : 2012 Article en page(s) : pp. 10247-10258 Note générale : Industrial chemistry Langues : Anglais (eng) Mots-clés : Modeling Dynamic model Molecular dynamics method Diffusion coefficient Résumé : An approach for computing Fick diffusivities directly from equilibrium molecular dynamics (MD) simulations is presented and demonstrated for a ternary chloroform―acetone―methanol liquid mixture. In our approach, Fick diffusivities are calculated from the Maawell―Stefan (MS) diffusivities and the so-called matrix of thermodynamic factors. MS diffusivities describe the friction between different molecular species and can be directly computed from MD simulations. The thermodynamic factor describes the deviation from ideal mixing behavior and is difficult to extract from both experiments and simulations. Here, we show that the thermodynamic factor in ternary systems can be obtained from density fluctuations in small subsystems embedded in a larger simulation box. Since the computation uses the Kirkwood―Buff coefficients, the present approach provides a general route toward the thermodynamics of the mixture. In experiments, Fick diffusion coefficients are measured, while previously equilibrium molecular dynamics simulation only provided MS transport diffusivities. Our approach provides an efficient and accurate route to predict multicomponent diffusion coefficients in liquids based on a consistent molecular picture and therefore bridges the gap between theory and experiment. ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=26201442
in Industrial & engineering chemistry research > Vol. 51 N° 30 (Août 2012) . - pp. 10247-10258[article] Fick diffusion coefficients in ternary liquid systems from equilibrium molecular dynamics simulations [texte imprimé] / Xin Liu, Auteur ; Ana Martín-Calvo, Auteur ; Erin McGarrity, Auteur . - 2012 . - pp. 10247-10258.
Industrial chemistry
Langues : Anglais (eng)
in Industrial & engineering chemistry research > Vol. 51 N° 30 (Août 2012) . - pp. 10247-10258
Mots-clés : Modeling Dynamic model Molecular dynamics method Diffusion coefficient Résumé : An approach for computing Fick diffusivities directly from equilibrium molecular dynamics (MD) simulations is presented and demonstrated for a ternary chloroform―acetone―methanol liquid mixture. In our approach, Fick diffusivities are calculated from the Maawell―Stefan (MS) diffusivities and the so-called matrix of thermodynamic factors. MS diffusivities describe the friction between different molecular species and can be directly computed from MD simulations. The thermodynamic factor describes the deviation from ideal mixing behavior and is difficult to extract from both experiments and simulations. Here, we show that the thermodynamic factor in ternary systems can be obtained from density fluctuations in small subsystems embedded in a larger simulation box. Since the computation uses the Kirkwood―Buff coefficients, the present approach provides a general route toward the thermodynamics of the mixture. In experiments, Fick diffusion coefficients are measured, while previously equilibrium molecular dynamics simulation only provided MS transport diffusivities. Our approach provides an efficient and accurate route to predict multicomponent diffusion coefficients in liquids based on a consistent molecular picture and therefore bridges the gap between theory and experiment. ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=26201442 Exemplaires
Code-barres Cote Support Localisation Section Disponibilité aucun exemplaire
Titre : Selective dibenzothiophene adsorption on graphene prepared using different methods Type de document : texte imprimé Auteurs : Hoon Sub Song, Auteur ; Chang Hyun Ko, Auteur ; Wook Ahn, Auteur Année de publication : 2012 Article en page(s) : pp.10259–10264 Note générale : Industrial chemistry Langues : Anglais (eng) Mots-clés : Dibenzothiophene Adsorption Résumé : Graphite oxide synthesized with phosphoric acid, labeled “GOP”, shows a higher degree of oxidation and has a larger interlayer spacing than the oxide prepared using the conventional Hummers method, referred to as “GOH”, as confirmed by X-ray photoelectron spectroscopy and X-ray diffraction analyses. This study was performed under the assumption that the oxygen-containing functional groups between the GOP layers are more easily reduced than those between the GOH layers. Raman analysis supported this assumption in that the reduced graphene from GOP has a larger number of sp2 carbons and fewer defects than the graphene obtained from GOH. The relative extent of defects in graphene can be investigated by dibenzothiophene (DBT) adsorption, which requires π–π interactions between the free π-bonds of sp2 atoms from graphene and those from the aromatic ring of DBT. The graphene obtained from GOP showed higher DBT adsorption capacity than that synthesized from GOH. In addition, the DBT adsorption capacity on graphene decreased as the concentrations of other aromatic compounds increased. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie301209c
in Industrial & engineering chemistry research > Vol. 51 N° 30 (Août 2012) . - pp.10259–10264[article] Selective dibenzothiophene adsorption on graphene prepared using different methods [texte imprimé] / Hoon Sub Song, Auteur ; Chang Hyun Ko, Auteur ; Wook Ahn, Auteur . - 2012 . - pp.10259–10264.
Industrial chemistry
Langues : Anglais (eng)
in Industrial & engineering chemistry research > Vol. 51 N° 30 (Août 2012) . - pp.10259–10264
Mots-clés : Dibenzothiophene Adsorption Résumé : Graphite oxide synthesized with phosphoric acid, labeled “GOP”, shows a higher degree of oxidation and has a larger interlayer spacing than the oxide prepared using the conventional Hummers method, referred to as “GOH”, as confirmed by X-ray photoelectron spectroscopy and X-ray diffraction analyses. This study was performed under the assumption that the oxygen-containing functional groups between the GOP layers are more easily reduced than those between the GOH layers. Raman analysis supported this assumption in that the reduced graphene from GOP has a larger number of sp2 carbons and fewer defects than the graphene obtained from GOH. The relative extent of defects in graphene can be investigated by dibenzothiophene (DBT) adsorption, which requires π–π interactions between the free π-bonds of sp2 atoms from graphene and those from the aromatic ring of DBT. The graphene obtained from GOP showed higher DBT adsorption capacity than that synthesized from GOH. In addition, the DBT adsorption capacity on graphene decreased as the concentrations of other aromatic compounds increased. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie301209c Exemplaires
Code-barres Cote Support Localisation Section Disponibilité aucun exemplaire
Titre : Numerical investigation of interaction between spheroid particles in tandem arrangement at moderate reynolds numbers Type de document : texte imprimé Auteurs : Nanda Kishore, Auteur Année de publication : 2012 Article en page(s) : pp. 10265-10273 Note générale : Industrial chemistry Langues : Anglais (eng) Mots-clés : Reynolds number Spheroid Résumé : In this work, effects of the particle aspect ratio (e), the particle Reynolds number (Re), and the interparticle distance (S) on the flow and drag phenomena of Newtonian fluid flow past a series of three spheroid particles are numerically investigated. The governing conservation equations of mass and momentum are solved using commercial software based on computational fluid dynamics. The numerical solver is benchmarked by comparing present results with those available in the literature for the case of tandem spherical particles (e = 1). Further, expensive new results are obtained over the following range of conditions: 1 ≤ Re ≤ 100, 0.25 ≤ e ≤ 2.5, and 2 ≤ S ≤ 6. The recirculation wake interactions are found to be more significant for prolate particles (e > 1) than for spheres (e = 1) followed by oblate spheroids (e ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=26201444
in Industrial & engineering chemistry research > Vol. 51 N° 30 (Août 2012) . - pp. 10265-10273[article] Numerical investigation of interaction between spheroid particles in tandem arrangement at moderate reynolds numbers [texte imprimé] / Nanda Kishore, Auteur . - 2012 . - pp. 10265-10273.
Industrial chemistry
Langues : Anglais (eng)
in Industrial & engineering chemistry research > Vol. 51 N° 30 (Août 2012) . - pp. 10265-10273
Mots-clés : Reynolds number Spheroid Résumé : In this work, effects of the particle aspect ratio (e), the particle Reynolds number (Re), and the interparticle distance (S) on the flow and drag phenomena of Newtonian fluid flow past a series of three spheroid particles are numerically investigated. The governing conservation equations of mass and momentum are solved using commercial software based on computational fluid dynamics. The numerical solver is benchmarked by comparing present results with those available in the literature for the case of tandem spherical particles (e = 1). Further, expensive new results are obtained over the following range of conditions: 1 ≤ Re ≤ 100, 0.25 ≤ e ≤ 2.5, and 2 ≤ S ≤ 6. The recirculation wake interactions are found to be more significant for prolate particles (e > 1) than for spheres (e = 1) followed by oblate spheroids (e ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=26201444 Exemplaires
Code-barres Cote Support Localisation Section Disponibilité aucun exemplaire
Titre : Thermodynamic modeling of aqueous ionic liquid solutions using PC - SAFT equation of state Type de document : texte imprimé Auteurs : Reza Shahriari, Auteur ; Mohammad Reza Dehghani, Auteur ; Bahman Behzadi, Auteur Année de publication : 2012 Article en page(s) : pp. 10274-10282 Note générale : Industrial chemistry Langues : Anglais (eng) Mots-clés : Thermodynamic properties Equations of state Ionic liquid Modeling Résumé : In this work, an equation of state has been utilized for thermodynamic modeling of aqueous ionic liquid (IL) solutions. The proposed equation of state is a combination of perturbed chain statistical associating fluid theory (PC-SAFT) equation of state and mean spherical approximation (MSA) term. In this model, the ion-based approach has been used to adjust the model parameters. The ion parameters have been estimated through simultaneous fitting to experimental mean ionic activity coefficient and liquid density data of strong electrolytes. Using adjusted ion parameters, osmotic coefficients, mean ionic activity coefficients, liquid densities, apparent molar volume, and water activity of several ILs, assumed as chainlike electrolytes, have been calculated. Results show that PC-SAFT, in combination with the MSA term has acceptable accuracy for prediction of density, apparent molar volume, and activity coefficient of ILs. The average deviations of predicted mean ionic activity coefficients, liquid densities, water activity, and apparent molar volume are 6.43, 0.86, 0.033, and 8.20%, respectively. ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=26201445
in Industrial & engineering chemistry research > Vol. 51 N° 30 (Août 2012) . - pp. 10274-10282[article] Thermodynamic modeling of aqueous ionic liquid solutions using PC - SAFT equation of state [texte imprimé] / Reza Shahriari, Auteur ; Mohammad Reza Dehghani, Auteur ; Bahman Behzadi, Auteur . - 2012 . - pp. 10274-10282.
Industrial chemistry
Langues : Anglais (eng)
in Industrial & engineering chemistry research > Vol. 51 N° 30 (Août 2012) . - pp. 10274-10282
Mots-clés : Thermodynamic properties Equations of state Ionic liquid Modeling Résumé : In this work, an equation of state has been utilized for thermodynamic modeling of aqueous ionic liquid (IL) solutions. The proposed equation of state is a combination of perturbed chain statistical associating fluid theory (PC-SAFT) equation of state and mean spherical approximation (MSA) term. In this model, the ion-based approach has been used to adjust the model parameters. The ion parameters have been estimated through simultaneous fitting to experimental mean ionic activity coefficient and liquid density data of strong electrolytes. Using adjusted ion parameters, osmotic coefficients, mean ionic activity coefficients, liquid densities, apparent molar volume, and water activity of several ILs, assumed as chainlike electrolytes, have been calculated. Results show that PC-SAFT, in combination with the MSA term has acceptable accuracy for prediction of density, apparent molar volume, and activity coefficient of ILs. The average deviations of predicted mean ionic activity coefficients, liquid densities, water activity, and apparent molar volume are 6.43, 0.86, 0.033, and 8.20%, respectively. ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=26201445 Exemplaires
Code-barres Cote Support Localisation Section Disponibilité aucun exemplaire
Titre : Scale inhibition and removal in continuous pulp digesters Type de document : texte imprimé Auteurs : Sujit Banerjee, Auteur ; Tuan Le, Auteur Année de publication : 2012 Article en page(s) : pp. 10283-10286 Note générale : Industrial chemistry Langues : Anglais (eng) Mots-clés : Calcium carbonate Pulp digesters Résumé : Calcium carbonate scaling occurs in the chip feed system and the cooking vessel of continuous digesters in pulp mills, and it arises from the reaction of calcium from wood chips with carbonate in the cooking liquor. Commercial antiscalants are typically expensive and rarely keep the system scale-free. Lignin derivatives have been proposed as antiscalants, because of their ability to chelate calcium, but they have not been adopted commercially. We demonstrate that addition of 1% black liquor to white liquor reduces or prevents calcium scaling, as shown by a simple new test that measures the degree to which scale resists abrasive removal from a metal surface. These findings were validated in a full-scale mill trial, where the black liquor not only inhibited calcium scale formation, but also removed existing scale. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie301352j
in Industrial & engineering chemistry research > Vol. 51 N° 30 (Août 2012) . - pp. 10283-10286[article] Scale inhibition and removal in continuous pulp digesters [texte imprimé] / Sujit Banerjee, Auteur ; Tuan Le, Auteur . - 2012 . - pp. 10283-10286.
Industrial chemistry
Langues : Anglais (eng)
in Industrial & engineering chemistry research > Vol. 51 N° 30 (Août 2012) . - pp. 10283-10286
Mots-clés : Calcium carbonate Pulp digesters Résumé : Calcium carbonate scaling occurs in the chip feed system and the cooking vessel of continuous digesters in pulp mills, and it arises from the reaction of calcium from wood chips with carbonate in the cooking liquor. Commercial antiscalants are typically expensive and rarely keep the system scale-free. Lignin derivatives have been proposed as antiscalants, because of their ability to chelate calcium, but they have not been adopted commercially. We demonstrate that addition of 1% black liquor to white liquor reduces or prevents calcium scaling, as shown by a simple new test that measures the degree to which scale resists abrasive removal from a metal surface. These findings were validated in a full-scale mill trial, where the black liquor not only inhibited calcium scale formation, but also removed existing scale. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie301352j Exemplaires
Code-barres Cote Support Localisation Section Disponibilité aucun exemplaire
