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Vol. 49 N° 6 - Mars 2010 [texte imprimé] . - 2010 . - p. 2537-3024 : ill. ; 28 cm. Chemical engineering Langues : Français (fre)
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Ajouter le résultat dans votre panierCompetition between electrochemical advanced oxidation and electrochemical hypochlorination of sulfamethoxazole at a boron-doped diamond anode / Jordache Boudreau in Industrial & engineering chemistry research, Vol. 49 N° 6 (Mars 2010)
Titre : Competition between electrochemical advanced oxidation and electrochemical hypochlorination of sulfamethoxazole at a boron-doped diamond anode Type de document : texte imprimé Auteurs : Jordache Boudreau, Auteur ; Dorin Bejan, Auteur ; Shuhuan Li, Auteur Année de publication : 2010 Article en page(s) : pp. 2537–2542 Note générale : Industrial Chemistry Langues : Anglais (eng) Mots-clés : Electrochemical Oxidation Hypochlorination Sulfamethoxazole Boron-Doped Diamond Anode Competition Résumé : Sulfamethoxazole (SMX) was used as a model substrate for electrochemical oxidation at a boron-doped diamond anode in the presence of chloride ion, which is present in many waste streams. In the absence of chloride, oxidation of SMX involves mineralization, an electrochemical advanced oxidation process (EAOP) that is initiated by attack of anode-derived hydroxyl radicals. The rate of disappearance of SMX increased monotonically upon addition of chloride ion but without inhibiting mineralization in the early stages of oxidation. This demonstrated that electrochemical hypochlorination (EH) and EAOP are not mutually exclusive reaction pathways; products of EH can undergo EAOP and vice versa. Persistent chlorinated byproducts were formed in the presence of chloride ion, indicating that chloride is a significant detriment to the success of EAOP. No mineralization was observed upon chemical hypochlorination of SMX with sodium hypochlorite. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie900614d
in Industrial & engineering chemistry research > Vol. 49 N° 6 (Mars 2010) . - pp. 2537–2542[article] Competition between electrochemical advanced oxidation and electrochemical hypochlorination of sulfamethoxazole at a boron-doped diamond anode [texte imprimé] / Jordache Boudreau, Auteur ; Dorin Bejan, Auteur ; Shuhuan Li, Auteur . - 2010 . - pp. 2537–2542.
Industrial Chemistry
Langues : Anglais (eng)
in Industrial & engineering chemistry research > Vol. 49 N° 6 (Mars 2010) . - pp. 2537–2542
Mots-clés : Electrochemical Oxidation Hypochlorination Sulfamethoxazole Boron-Doped Diamond Anode Competition Résumé : Sulfamethoxazole (SMX) was used as a model substrate for electrochemical oxidation at a boron-doped diamond anode in the presence of chloride ion, which is present in many waste streams. In the absence of chloride, oxidation of SMX involves mineralization, an electrochemical advanced oxidation process (EAOP) that is initiated by attack of anode-derived hydroxyl radicals. The rate of disappearance of SMX increased monotonically upon addition of chloride ion but without inhibiting mineralization in the early stages of oxidation. This demonstrated that electrochemical hypochlorination (EH) and EAOP are not mutually exclusive reaction pathways; products of EH can undergo EAOP and vice versa. Persistent chlorinated byproducts were formed in the presence of chloride ion, indicating that chloride is a significant detriment to the success of EAOP. No mineralization was observed upon chemical hypochlorination of SMX with sodium hypochlorite. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie900614d Exemplaires
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Titre : Hydrogenation and oxidation reactions involving ruthenium supported catalysts Type de document : texte imprimé Auteurs : Rikesh Joshi, Auteur ; Uma Chudasama, Auteur Année de publication : 2010 Article en page(s) : pp. 2543–2547 Note générale : Industrial Chemistry Langues : Anglais (eng) Mots-clés : Hydrogenation Oxidation Involving Ruthenium Supported Catalysts Résumé : The present study involves synthesis and characterization of M(IV) phosphates and tungstates which are inorganic cation exchangers of the class of tetravalent metal acid (tma) salts possessing structural hydroxyl groups, the H of the structural −OH being the cation exchange sites, which indicates good potential for application as supports in heterogenized homogeneous catalysis. Ru(III) has been exchanged onto these materials by an ion exchange technique and catalytic activity investigated for oxidation of benzyl alcohol and styrene. Further, Ru(III) has been reduced to Ru(0) and catalytic activity has been explored for hydrogenation of 1-octene, nitro benzene, and cyclohexanone. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie9008309
in Industrial & engineering chemistry research > Vol. 49 N° 6 (Mars 2010) . - pp. 2543–2547[article] Hydrogenation and oxidation reactions involving ruthenium supported catalysts [texte imprimé] / Rikesh Joshi, Auteur ; Uma Chudasama, Auteur . - 2010 . - pp. 2543–2547.
Industrial Chemistry
Langues : Anglais (eng)
in Industrial & engineering chemistry research > Vol. 49 N° 6 (Mars 2010) . - pp. 2543–2547
Mots-clés : Hydrogenation Oxidation Involving Ruthenium Supported Catalysts Résumé : The present study involves synthesis and characterization of M(IV) phosphates and tungstates which are inorganic cation exchangers of the class of tetravalent metal acid (tma) salts possessing structural hydroxyl groups, the H of the structural −OH being the cation exchange sites, which indicates good potential for application as supports in heterogenized homogeneous catalysis. Ru(III) has been exchanged onto these materials by an ion exchange technique and catalytic activity investigated for oxidation of benzyl alcohol and styrene. Further, Ru(III) has been reduced to Ru(0) and catalytic activity has been explored for hydrogenation of 1-octene, nitro benzene, and cyclohexanone. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie9008309 Exemplaires
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Titre : Novel polycarboxylated starch-Bbased sorbents for Cu2+ ions Type de document : texte imprimé Auteurs : Kalpana Chauhan, Auteur ; Ghanshyam S. Chauhan, Auteur ; J. H. Ahn, Auteur Année de publication : 2010 Article en page(s) : pp. 2548–2556 Note générale : Industrial Chemistry Langues : Anglais (eng) Mots-clés : Sorbents Polycarboxylated Starch Cu2+ Ions Résumé : In this article we report use of novel starch-based functional hydrogels as Cu2+ ions sorbents. Starch was functionalized by acid hydrolysis and/or oxidized by nitrogen oxides to generate carboxylic groups at C-6. Sorption of Cu2+ ions was studied as a function of hydrogel structure and environmental factors. Hydrogels exhibit structure−property relationship in the sorption of Cu2+ ions. The hydrogel that exhibited the maximum ion uptake was used to investigate the effect of contact time, temperature, pH, and Cu2+ ions concentration on the sorption capacity. The maximum sorption capacity of 128.26 mg g−1 was obtained in 2 h at 40 °C, 7.0 pH, and 50 ppm of Cu2+ ions. Sorption data show good match both with Langmuir and Freundlich isotherms and obey pseudo-second-order kinetics. Cu2+ ions bind to sorbents by chelation. Evidence of Cu2+ uptake on hydrogels was obtained from FTIR spectrum of the ions-loaded hydrogel. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie9009952
in Industrial & engineering chemistry research > Vol. 49 N° 6 (Mars 2010) . - pp. 2548–2556[article] Novel polycarboxylated starch-Bbased sorbents for Cu2+ ions [texte imprimé] / Kalpana Chauhan, Auteur ; Ghanshyam S. Chauhan, Auteur ; J. H. Ahn, Auteur . - 2010 . - pp. 2548–2556.
Industrial Chemistry
Langues : Anglais (eng)
in Industrial & engineering chemistry research > Vol. 49 N° 6 (Mars 2010) . - pp. 2548–2556
Mots-clés : Sorbents Polycarboxylated Starch Cu2+ Ions Résumé : In this article we report use of novel starch-based functional hydrogels as Cu2+ ions sorbents. Starch was functionalized by acid hydrolysis and/or oxidized by nitrogen oxides to generate carboxylic groups at C-6. Sorption of Cu2+ ions was studied as a function of hydrogel structure and environmental factors. Hydrogels exhibit structure−property relationship in the sorption of Cu2+ ions. The hydrogel that exhibited the maximum ion uptake was used to investigate the effect of contact time, temperature, pH, and Cu2+ ions concentration on the sorption capacity. The maximum sorption capacity of 128.26 mg g−1 was obtained in 2 h at 40 °C, 7.0 pH, and 50 ppm of Cu2+ ions. Sorption data show good match both with Langmuir and Freundlich isotherms and obey pseudo-second-order kinetics. Cu2+ ions bind to sorbents by chelation. Evidence of Cu2+ uptake on hydrogels was obtained from FTIR spectrum of the ions-loaded hydrogel. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie9009952 Exemplaires
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Titre : Chitosan-type bioadditive-modified electronic industry waste sludge for heavy metal stabilization with assistance of microwave heating Type de document : texte imprimé Auteurs : Rajabathar Jothiramalingam, Auteur ; Shang-Lien Lo, Auteur ; Lan-Anh Phanthi, Auteur Année de publication : 2010 Article en page(s) : pp. 2557–2561 Note générale : Industrial Chemistry Langues : Anglais (eng) Mots-clés : Chitosan Bioadditive Electronic Industry Waste Sludge Heavy Metal Stabilization Microwave Heating Résumé : Cement solidification is used as the common method for stabilizing industrial wastewater sludge in Taiwan. However, this method has the disadvantage of increasing the volume of waste. In contrast, chitosan-type biopolymer is used by several researchers for biosorption applications and dye discoloration in aqueous solutions. Therefore, in this study, commercially available low-cost chitosan-type material was used as an alternative bioadditive to stabilize the leaching of heavy metal ions in industrial sludge. The effects of additive dosage amount, power of microwave irradiation, and reaction time were studied. The heavy metal leaching capacity was determined using a standard TCLP test, and the elemental content in the leachate was analyzed by ICP. It was found that chitosan effectively stabilizes copper ions with higher selectivity in the presence of microwave irradiation and other toxic heavy metal ions. The optimized additive mixing in industrial sludge for the control of the leaching of copper and other heavy metal ions was found to be ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie9011408
in Industrial & engineering chemistry research > Vol. 49 N° 6 (Mars 2010) . - pp. 2557–2561[article] Chitosan-type bioadditive-modified electronic industry waste sludge for heavy metal stabilization with assistance of microwave heating [texte imprimé] / Rajabathar Jothiramalingam, Auteur ; Shang-Lien Lo, Auteur ; Lan-Anh Phanthi, Auteur . - 2010 . - pp. 2557–2561.
Industrial Chemistry
Langues : Anglais (eng)
in Industrial & engineering chemistry research > Vol. 49 N° 6 (Mars 2010) . - pp. 2557–2561
Mots-clés : Chitosan Bioadditive Electronic Industry Waste Sludge Heavy Metal Stabilization Microwave Heating Résumé : Cement solidification is used as the common method for stabilizing industrial wastewater sludge in Taiwan. However, this method has the disadvantage of increasing the volume of waste. In contrast, chitosan-type biopolymer is used by several researchers for biosorption applications and dye discoloration in aqueous solutions. Therefore, in this study, commercially available low-cost chitosan-type material was used as an alternative bioadditive to stabilize the leaching of heavy metal ions in industrial sludge. The effects of additive dosage amount, power of microwave irradiation, and reaction time were studied. The heavy metal leaching capacity was determined using a standard TCLP test, and the elemental content in the leachate was analyzed by ICP. It was found that chitosan effectively stabilizes copper ions with higher selectivity in the presence of microwave irradiation and other toxic heavy metal ions. The optimized additive mixing in industrial sludge for the control of the leaching of copper and other heavy metal ions was found to be ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie9011408 Exemplaires
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Titre : Kinetic and pseudo-second-order modeling of lead biosorption onto pine cone powder Type de document : texte imprimé Auteurs : A. E. Ofomaja, Auteur ; E. B. Naidoo, Auteur ; S. J. Modise, Auteur Année de publication : 2010 Article en page(s) : pp. 2562–2572 Note générale : Industrial Chemistry Langues : Anglais (eng) Mots-clés : Kinetic Pseudo Modeling Lead Biosorption Pine Cone Powder Résumé : The sorption of lead(II) onto pine cone powder (PCP) and 0.15 mol/L NaOH treated pine cone powder (PCP 0.15), an abundant agricultural waste from the wood industry, was studied to evaluate the effect of NaOH treatment on the kinetics of lead(II) uptake by performing batch kinetic sorption experiments. Batch biosorption kinetics was performed by varying biosorbent dose and initial lead(II) concentration and the kinetic data modeled using the pseudo-first, pseudo-second intraparticle, and Bangham diffusion models. The results revealed that NaOH treatment changed the pattern of the biosorption kinetics, the biosorption kinetic parameters, and influenced the rate-limiting step. The pseudo-second-order kinetic model gave a better fitting of the kinetic data for both PCP and PCP 0.15. The batch biosorption model, based on the pseudo-second-order mechanism, was applied to predict the rate constant of biosorption, the equilibrium capacity, the initial sorption rate, the effects of biosorbent dose, and initial lead(II) concentration. Equilibrium concentrations were evaluated with the equilibrium capacity obtained from the pseudo-second-order rate equation. In addition, pseudo-isotherms were obtained by changing initial lead(II) concentration using the equilibrium concentration and equilibrium capacity obtained based on the pseudo-second-order constants. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie901150x
in Industrial & engineering chemistry research > Vol. 49 N° 6 (Mars 2010) . - pp. 2562–2572[article] Kinetic and pseudo-second-order modeling of lead biosorption onto pine cone powder [texte imprimé] / A. E. Ofomaja, Auteur ; E. B. Naidoo, Auteur ; S. J. Modise, Auteur . - 2010 . - pp. 2562–2572.
Industrial Chemistry
Langues : Anglais (eng)
in Industrial & engineering chemistry research > Vol. 49 N° 6 (Mars 2010) . - pp. 2562–2572
Mots-clés : Kinetic Pseudo Modeling Lead Biosorption Pine Cone Powder Résumé : The sorption of lead(II) onto pine cone powder (PCP) and 0.15 mol/L NaOH treated pine cone powder (PCP 0.15), an abundant agricultural waste from the wood industry, was studied to evaluate the effect of NaOH treatment on the kinetics of lead(II) uptake by performing batch kinetic sorption experiments. Batch biosorption kinetics was performed by varying biosorbent dose and initial lead(II) concentration and the kinetic data modeled using the pseudo-first, pseudo-second intraparticle, and Bangham diffusion models. The results revealed that NaOH treatment changed the pattern of the biosorption kinetics, the biosorption kinetic parameters, and influenced the rate-limiting step. The pseudo-second-order kinetic model gave a better fitting of the kinetic data for both PCP and PCP 0.15. The batch biosorption model, based on the pseudo-second-order mechanism, was applied to predict the rate constant of biosorption, the equilibrium capacity, the initial sorption rate, the effects of biosorbent dose, and initial lead(II) concentration. Equilibrium concentrations were evaluated with the equilibrium capacity obtained from the pseudo-second-order rate equation. In addition, pseudo-isotherms were obtained by changing initial lead(II) concentration using the equilibrium concentration and equilibrium capacity obtained based on the pseudo-second-order constants. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie901150x Exemplaires
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Titre : Catalytic upgrading of biomass fast pyrolysis vapors with Pd/SBA-15 catalysts Type de document : texte imprimé Auteurs : Qiang Lu, Auteur ; Zhe Tang, Auteur ; Ying Zhang, Auteur Année de publication : 2010 Article en page(s) : pp. 2573–2580 Note générale : Industrial Chemistry Langues : Anglais (eng) Mots-clés : Catalytic Upgrading Biomass Fast Pyrolysis Vapors Pd/SBA-15 Catalysts Résumé : Palladium supported on SBA-15 catalysts were developed and employed for catalytic cracking of biomass fast pyrolysis vapors using analytical pyrolysis−gas chromatography/mass spectrometry (Py-GC/MS). The Pd/SBA-15 catalysts displayed prominent capabilities to crack the lignin-derived oligomers to monomeric phenolic compounds and further convert them to phenols without the carbonyl group and unsaturated C−C bond on the side chain. Moreover, the catalysts almost completely eliminated the anhydrosugar products and decarbonylated the furan compounds. They also significantly decreased the linear aldehydes and dehydroxylated the linear ketones. In addition, the catalysts slightly decreased the acids, while methanol and hydrocarbons were increased. The above catalytic capabilities of the Pd/SBA-15 catalyst were enhanced with the increase of Pd content from 0.79 wt % to 3.01 wt %. ISSN : 08885-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie901198s
in Industrial & engineering chemistry research > Vol. 49 N° 6 (Mars 2010) . - pp. 2573–2580[article] Catalytic upgrading of biomass fast pyrolysis vapors with Pd/SBA-15 catalysts [texte imprimé] / Qiang Lu, Auteur ; Zhe Tang, Auteur ; Ying Zhang, Auteur . - 2010 . - pp. 2573–2580.
Industrial Chemistry
Langues : Anglais (eng)
in Industrial & engineering chemistry research > Vol. 49 N° 6 (Mars 2010) . - pp. 2573–2580
Mots-clés : Catalytic Upgrading Biomass Fast Pyrolysis Vapors Pd/SBA-15 Catalysts Résumé : Palladium supported on SBA-15 catalysts were developed and employed for catalytic cracking of biomass fast pyrolysis vapors using analytical pyrolysis−gas chromatography/mass spectrometry (Py-GC/MS). The Pd/SBA-15 catalysts displayed prominent capabilities to crack the lignin-derived oligomers to monomeric phenolic compounds and further convert them to phenols without the carbonyl group and unsaturated C−C bond on the side chain. Moreover, the catalysts almost completely eliminated the anhydrosugar products and decarbonylated the furan compounds. They also significantly decreased the linear aldehydes and dehydroxylated the linear ketones. In addition, the catalysts slightly decreased the acids, while methanol and hydrocarbons were increased. The above catalytic capabilities of the Pd/SBA-15 catalyst were enhanced with the increase of Pd content from 0.79 wt % to 3.01 wt %. ISSN : 08885-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie901198s Exemplaires
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Titre : Liquid−liquid extraction of low-concentration aniline from aqueous solutions with salts Type de document : texte imprimé Auteurs : Xiaohua Wu, Auteur ; Zhigang Lei, Auteur ; Qunsheng Li, Auteur Année de publication : 2010 Article en page(s) : pp. 2581–2588 Note générale : Idustrial Chemistry Langues : Anglais (eng) Mots-clés : Liquid Extraction Low-Concentration Aniline Aqueous Solutions Salts Résumé : The focus of this work was to concentrate aniline at low concentration from water samples using liquid−liquid extraction with salts. The salts included inorganic solid salts and ionic liquids and were added to the system of water + aniline + MTBE (methyl tert-butyl ether) to intensify the conventional liquid−liquid extraction process. The influence of such factors as extraction time, initial aqueous aniline concentration, phase volume ratio, and extraction temperature on the extraction process was investigated to determine the optimum extraction conditions. It was found that the salting effect of K2CO3 on aniline and water is the highest among all of the salts investigated, whereas the imidazolium-based ionic liquids do not bring about a good extraction efficiency as expected. The complex formation and interaction force of the systems containing salts were determined using FTIR (Fourier transform infrared) spectrometry and density functional theory (DFT). This work also tries to explain the separation mechanism by means of the Hofmeister series and quantum chemistry. ISSN : 0885-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie9012979
in Industrial & engineering chemistry research > Vol. 49 N° 6 (Mars 2010) . - pp. 2581–2588[article] Liquid−liquid extraction of low-concentration aniline from aqueous solutions with salts [texte imprimé] / Xiaohua Wu, Auteur ; Zhigang Lei, Auteur ; Qunsheng Li, Auteur . - 2010 . - pp. 2581–2588.
Idustrial Chemistry
Langues : Anglais (eng)
in Industrial & engineering chemistry research > Vol. 49 N° 6 (Mars 2010) . - pp. 2581–2588
Mots-clés : Liquid Extraction Low-Concentration Aniline Aqueous Solutions Salts Résumé : The focus of this work was to concentrate aniline at low concentration from water samples using liquid−liquid extraction with salts. The salts included inorganic solid salts and ionic liquids and were added to the system of water + aniline + MTBE (methyl tert-butyl ether) to intensify the conventional liquid−liquid extraction process. The influence of such factors as extraction time, initial aqueous aniline concentration, phase volume ratio, and extraction temperature on the extraction process was investigated to determine the optimum extraction conditions. It was found that the salting effect of K2CO3 on aniline and water is the highest among all of the salts investigated, whereas the imidazolium-based ionic liquids do not bring about a good extraction efficiency as expected. The complex formation and interaction force of the systems containing salts were determined using FTIR (Fourier transform infrared) spectrometry and density functional theory (DFT). This work also tries to explain the separation mechanism by means of the Hofmeister series and quantum chemistry. ISSN : 0885-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie9012979 Exemplaires
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Titre : Synthesis of biodegradable high-alkali magnesium oleate detergent Type de document : texte imprimé Auteurs : Yonglei Wang, Auteur ; Wumanjiang Eli, Auteur Année de publication : 2010 Article en page(s) : pp. 2589–2592 Note générale : Industrial Chemistry Langues : Anglais (eng) Mots-clés : Synthesis Biodegradable Alkali Magnesium Oleate Detergent Résumé : This article covers a method for synthesizing biodegradable high-alkali magnesium oleate detergent with a total base number (TBN) value of 256 mg KOH/g. The biodegradable, environmentally friendly high-alkali magnesium oleate detergent was synthesized using oleic acid and magnesium oxide (Light) as raw materials. Reaction conditions including the choice of alkaline magnesium salt, the molar ratio of magnesium oxide to oleic acid, the amount of methanol, the amount of ammonia, the carbonation temperature, the molar ratio of water to magnesium oxide, the gas flow rate of CO2, and the molar ratio of injected CO2 to magnesium oxide were optimized. Under the optimized conditions, a high-alkali magnesium oleate detergent with TBN of 256 mg KOH/g could be obtained. ISSN : 05888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie901569g
in Industrial & engineering chemistry research > Vol. 49 N° 6 (Mars 2010) . - pp. 2589–2592[article] Synthesis of biodegradable high-alkali magnesium oleate detergent [texte imprimé] / Yonglei Wang, Auteur ; Wumanjiang Eli, Auteur . - 2010 . - pp. 2589–2592.
Industrial Chemistry
Langues : Anglais (eng)
in Industrial & engineering chemistry research > Vol. 49 N° 6 (Mars 2010) . - pp. 2589–2592
Mots-clés : Synthesis Biodegradable Alkali Magnesium Oleate Detergent Résumé : This article covers a method for synthesizing biodegradable high-alkali magnesium oleate detergent with a total base number (TBN) value of 256 mg KOH/g. The biodegradable, environmentally friendly high-alkali magnesium oleate detergent was synthesized using oleic acid and magnesium oxide (Light) as raw materials. Reaction conditions including the choice of alkaline magnesium salt, the molar ratio of magnesium oxide to oleic acid, the amount of methanol, the amount of ammonia, the carbonation temperature, the molar ratio of water to magnesium oxide, the gas flow rate of CO2, and the molar ratio of injected CO2 to magnesium oxide were optimized. Under the optimized conditions, a high-alkali magnesium oleate detergent with TBN of 256 mg KOH/g could be obtained. ISSN : 05888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie901569g Exemplaires
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Titre : Adsorption and corrosion inhibition behavior of mild steel by one derivative of benzoic−triazole in acidic solution Type de document : texte imprimé Auteurs : Zhihua Tao, Auteur ; Shengtao Zhang, Auteur ; Weihua Li, Auteur Année de publication : 2010 Article en page(s) : pp. 2593–2599 Note générale : Industrial Chemistry Langues : Anglais (eng) Mots-clés : Adsorption Corrosion Inhibition Behavior Mild Steel Benzoic Triazole Acidic Résumé : A newly synthesized benzoic−triazole derivative 3,5-dimethylbenzoic acid [1,2,4]triazol-1-ylmethyl ester (DBT) was investigated as a corrosion inhibitor of mild steel in 1 M HCl solution using weight loss measurements, potentiodynamic polarization, SEM, and EIS methods. The results revealed that DBT was an excellent inhibitor, and the inhibition efficiencies obtained from weight loss and electrochemical experiments were in good agreement. Using the potentiodynamic polarization technique, the inhibitor was proved to have a mixed-type character for mild steel by suppressing both anodic and cathodic reactions on the metal surface. The number of water molecules (X) replaced by a molecule of organic adsorbate was determined from the Flory−Huggins, Dhar−Flory−Huggins, and Bockris−Swinkels substitutional adsorption isotherms applied to the data obtained from the gravimetric experiments performed on a mild steel specimen in 1 M HCl solution at 298 K. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie901774m
in Industrial & engineering chemistry research > Vol. 49 N° 6 (Mars 2010) . - pp. 2593–2599[article] Adsorption and corrosion inhibition behavior of mild steel by one derivative of benzoic−triazole in acidic solution [texte imprimé] / Zhihua Tao, Auteur ; Shengtao Zhang, Auteur ; Weihua Li, Auteur . - 2010 . - pp. 2593–2599.
Industrial Chemistry
Langues : Anglais (eng)
in Industrial & engineering chemistry research > Vol. 49 N° 6 (Mars 2010) . - pp. 2593–2599
Mots-clés : Adsorption Corrosion Inhibition Behavior Mild Steel Benzoic Triazole Acidic Résumé : A newly synthesized benzoic−triazole derivative 3,5-dimethylbenzoic acid [1,2,4]triazol-1-ylmethyl ester (DBT) was investigated as a corrosion inhibitor of mild steel in 1 M HCl solution using weight loss measurements, potentiodynamic polarization, SEM, and EIS methods. The results revealed that DBT was an excellent inhibitor, and the inhibition efficiencies obtained from weight loss and electrochemical experiments were in good agreement. Using the potentiodynamic polarization technique, the inhibitor was proved to have a mixed-type character for mild steel by suppressing both anodic and cathodic reactions on the metal surface. The number of water molecules (X) replaced by a molecule of organic adsorbate was determined from the Flory−Huggins, Dhar−Flory−Huggins, and Bockris−Swinkels substitutional adsorption isotherms applied to the data obtained from the gravimetric experiments performed on a mild steel specimen in 1 M HCl solution at 298 K. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie901774m Exemplaires
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Titre : The dissolution kinetics of gibbsite in sodium hydroxide at ambient pressure Type de document : texte imprimé Auteurs : Henrik Grenman, Auteur ; Tapio Salmi, Auteur ; Dmitry Yu, Auteur Année de publication : 2010 Article en page(s) : pp. 2600–2607 Note générale : Industrial Chemistry Langues : Anglais (eng) Mots-clés : Dissolution Kinetics Gibbsite Sodium Hydroxide Ambient Pressure Résumé : The dissolution kinetics of pure gibbsite in concentrated sodium hydroxide solutions was studied. The experiments were performed under ambient pressure and at 60−85 °C. The changes in morphology of the solid phase were studied during the reaction by particle size, porosity, and surface area measurements as well as scanning electron microscopy. Reaction rates were observed to be strongly dependent on temperature and hydroxide concentration. Several kinetic models, based on different representation of the surface area of gibbsite, were compared to the experimental data and a good correlation between a model incorporating rough/porous geometry and the experimental data was obtained. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie901803v
in Industrial & engineering chemistry research > Vol. 49 N° 6 (Mars 2010) . - pp. 2600–2607[article] The dissolution kinetics of gibbsite in sodium hydroxide at ambient pressure [texte imprimé] / Henrik Grenman, Auteur ; Tapio Salmi, Auteur ; Dmitry Yu, Auteur . - 2010 . - pp. 2600–2607.
Industrial Chemistry
Langues : Anglais (eng)
in Industrial & engineering chemistry research > Vol. 49 N° 6 (Mars 2010) . - pp. 2600–2607
Mots-clés : Dissolution Kinetics Gibbsite Sodium Hydroxide Ambient Pressure Résumé : The dissolution kinetics of pure gibbsite in concentrated sodium hydroxide solutions was studied. The experiments were performed under ambient pressure and at 60−85 °C. The changes in morphology of the solid phase were studied during the reaction by particle size, porosity, and surface area measurements as well as scanning electron microscopy. Reaction rates were observed to be strongly dependent on temperature and hydroxide concentration. Several kinetic models, based on different representation of the surface area of gibbsite, were compared to the experimental data and a good correlation between a model incorporating rough/porous geometry and the experimental data was obtained. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie901803v Exemplaires
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Titre : Sulfonated styrene−divinybenzene resins : optimizing synthesis and estimating characteristics of the base copolymers and the resins Type de document : texte imprimé Auteurs : Muhammad Arif Malik, Auteur ; Syed Wasim Ali, Auteur ; Imtiaz Ahmed, Auteur Année de publication : 2010 Article en page(s) : pp. 2608–2612 Note générale : Industrial Chemistry Langues : Anglais (eng) Mots-clés : Sulfonated Styrene Divinybenzene Resins Optimizing Synthesis Characteristics Base Copolymers Résumé : Maximum sulfonation and minimum carboxylation are desirable in sulfonated styrene−divinylbenzene cation-exchange resins. These characteristics may be achieved with greater control of porosity of the base copolymers. Optimization of the porosity by varying both the nature and amount of porogen, and cross-linking for maximizing sulfonation and minimizing carboxylation, are reported. Predictors of the characteristics obtained by statistical analysis of the data, and the ranges of conditions in which they can be employed, are discussed. The optimum conditions are cross-linking 20% to 23% and pore volume 0.14 mL/g to 0.3 mL/g. The relationship of the particle size with porosity of the base copolymer and capacity of the resins is discussed. The effects of residual porogen/homopolymer on the sulfonation of these copolymers are also discussed. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie902057x
in Industrial & engineering chemistry research > Vol. 49 N° 6 (Mars 2010) . - pp. 2608–2612[article] Sulfonated styrene−divinybenzene resins : optimizing synthesis and estimating characteristics of the base copolymers and the resins [texte imprimé] / Muhammad Arif Malik, Auteur ; Syed Wasim Ali, Auteur ; Imtiaz Ahmed, Auteur . - 2010 . - pp. 2608–2612.
Industrial Chemistry
Langues : Anglais (eng)
in Industrial & engineering chemistry research > Vol. 49 N° 6 (Mars 2010) . - pp. 2608–2612
Mots-clés : Sulfonated Styrene Divinybenzene Resins Optimizing Synthesis Characteristics Base Copolymers Résumé : Maximum sulfonation and minimum carboxylation are desirable in sulfonated styrene−divinylbenzene cation-exchange resins. These characteristics may be achieved with greater control of porosity of the base copolymers. Optimization of the porosity by varying both the nature and amount of porogen, and cross-linking for maximizing sulfonation and minimizing carboxylation, are reported. Predictors of the characteristics obtained by statistical analysis of the data, and the ranges of conditions in which they can be employed, are discussed. The optimum conditions are cross-linking 20% to 23% and pore volume 0.14 mL/g to 0.3 mL/g. The relationship of the particle size with porosity of the base copolymer and capacity of the resins is discussed. The effects of residual porogen/homopolymer on the sulfonation of these copolymers are also discussed. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie902057x Exemplaires
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Titre : Two-phase flow and bubble size distribution in air-sparged and surface-aerated vessels stirred by a dual impeller Type de document : texte imprimé Auteurs : Giuseppina Montante, Auteur ; Fabio Laurenzi, Auteur ; Alessandro Paglianti, Auteur Année de publication : 2010 Article en page(s) : pp. 2613–2623 Note générale : Industrial Chemistry Langues : Anglais (eng) Mots-clés : Flow Bubble Size Distribution Air Sparged Surface-Aerated Vessels Dual Impeller Résumé : The aim of this work is to investigate the turbulent hydrodynamic features of a fully baffled gas−liquid stirred vessel equipped with a dual turbine consisting of a radial concave-blade turbine and a downflow pitched blade turbine (PBT). Two different operating modes are analyzed, namely air sparged and surface aerated. A two-phase particle image velocimetry (PIV) technique, based on a single laser sheet source and two cameras, each provided with a filter for separately catching the light scattered by the liquid seeding particles or the bubbles, was adopted for detecting independently and simultaneously the liquid and bubble phase velocities. The mean flow fields of the gas and liquid phases, the rms velocity fluctuation maps of the two phases, and a comparison with the corresponding velocity measurements effected in single-phase conditions are presented. The typical bubble size distribution (BSD) in the two gas−liquid systems obtained by a digital image processing method is also presented, and its dependency on the gas feeding configuration and on the dimensionless Weber number is shown. The effects on the hydrodynamic behavior of the gas−liquid dispersion of liquid viscosity as well as of gas flow rate or impeller speed for the air-sparged and surface-aerated systems, respectively, are discussed. The results suggest that simultaneous detection of the flow fields of the two phases is required for appropriate, detailed evaluation of the system features. Even a limited viscosity change has a significant impact on the system hydrodynamics, since it affects both the flow field and the BSD. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie9006276
in Industrial & engineering chemistry research > Vol. 49 N° 6 (Mars 2010) . - pp. 2613–2623[article] Two-phase flow and bubble size distribution in air-sparged and surface-aerated vessels stirred by a dual impeller [texte imprimé] / Giuseppina Montante, Auteur ; Fabio Laurenzi, Auteur ; Alessandro Paglianti, Auteur . - 2010 . - pp. 2613–2623.
Industrial Chemistry
Langues : Anglais (eng)
in Industrial & engineering chemistry research > Vol. 49 N° 6 (Mars 2010) . - pp. 2613–2623
Mots-clés : Flow Bubble Size Distribution Air Sparged Surface-Aerated Vessels Dual Impeller Résumé : The aim of this work is to investigate the turbulent hydrodynamic features of a fully baffled gas−liquid stirred vessel equipped with a dual turbine consisting of a radial concave-blade turbine and a downflow pitched blade turbine (PBT). Two different operating modes are analyzed, namely air sparged and surface aerated. A two-phase particle image velocimetry (PIV) technique, based on a single laser sheet source and two cameras, each provided with a filter for separately catching the light scattered by the liquid seeding particles or the bubbles, was adopted for detecting independently and simultaneously the liquid and bubble phase velocities. The mean flow fields of the gas and liquid phases, the rms velocity fluctuation maps of the two phases, and a comparison with the corresponding velocity measurements effected in single-phase conditions are presented. The typical bubble size distribution (BSD) in the two gas−liquid systems obtained by a digital image processing method is also presented, and its dependency on the gas feeding configuration and on the dimensionless Weber number is shown. The effects on the hydrodynamic behavior of the gas−liquid dispersion of liquid viscosity as well as of gas flow rate or impeller speed for the air-sparged and surface-aerated systems, respectively, are discussed. The results suggest that simultaneous detection of the flow fields of the two phases is required for appropriate, detailed evaluation of the system features. Even a limited viscosity change has a significant impact on the system hydrodynamics, since it affects both the flow field and the BSD. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie9006276 Exemplaires
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Titre : Catalytic vapor phase epoxidation of propene with nitrous oxide as an oxidant : investigations on catalyst composition and reaction conditions Type de document : texte imprimé Auteurs : Thomas Thömmes, Auteur ; Ingo Gräf, Auteur ; Andreas Reitzmann, Auteur Année de publication : 2010 Article en page(s) : pp. 2624–2637 Note générale : Industrial Chemistry Langues : Anglais (eng) Mots-clés : Catalytic Vapor Epoxidation Propene Nitrous Oxide Oxidant Investigations Catalyst Composition Résumé : The vapor phase epoxidation of propene with nitrous oxide (N2O) was experimentally investigated in a fixed bed reactor using different Csx/Fey/SiO2 catalysts. This was done with a systematic approach which comprises the derivation of kinetic parameters for directly comparing catalyst performance. Therefore, kinetic measurements were made for each catalyst by variation of the residence time. It was found that the addition of an alkali promoter to the Fey/SiO2 catalyst is essential for the formation of propylene oxide and a proper alkali/Fe molar ratio is crucial for both activity and selectivity. Maxima in both activity and selectivity were observed for alkali/Fe ratios in the region 1.2−1.7. A further increase in activity without any loss in selectivity was obtained by adjusting the calcination temperature to 783 K. The conversion of PO was used as a tool to measure the product stability and a minimum reaction rate was also found for alkali/Fe ratios in the region 1.2−1.7. The promoter is responsible for the formation of active centers and it reduces surface acidity which leads to an increased stability of PO through the inhibition of the consecutive conversion. Maximum selectivities to PO of about 40% at 5−10% conversion were achieved at moderate reaction temperatures of 648 K. Because of parallel and consecutive formation of carbonaceous deposits on the catalyst, the catalyst deactivated within 2 h of operation to a remaining activity of around 40%. Neglecting the carbonaceous deposits as a reaction product and considering only the vapor phase products, PO selectivity is more than 75% at 5−10% propene conversion. The attempt to slow down the deactivation through the addition of supplementary gases (H2, O2, NH3, H2O) was partially successful, but unfortunately this is always accompanied by lower PO selectivity. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie901342t
in Industrial & engineering chemistry research > Vol. 49 N° 6 (Mars 2010) . - pp. 2624–2637[article] Catalytic vapor phase epoxidation of propene with nitrous oxide as an oxidant : investigations on catalyst composition and reaction conditions [texte imprimé] / Thomas Thömmes, Auteur ; Ingo Gräf, Auteur ; Andreas Reitzmann, Auteur . - 2010 . - pp. 2624–2637.
Industrial Chemistry
Langues : Anglais (eng)
in Industrial & engineering chemistry research > Vol. 49 N° 6 (Mars 2010) . - pp. 2624–2637
Mots-clés : Catalytic Vapor Epoxidation Propene Nitrous Oxide Oxidant Investigations Catalyst Composition Résumé : The vapor phase epoxidation of propene with nitrous oxide (N2O) was experimentally investigated in a fixed bed reactor using different Csx/Fey/SiO2 catalysts. This was done with a systematic approach which comprises the derivation of kinetic parameters for directly comparing catalyst performance. Therefore, kinetic measurements were made for each catalyst by variation of the residence time. It was found that the addition of an alkali promoter to the Fey/SiO2 catalyst is essential for the formation of propylene oxide and a proper alkali/Fe molar ratio is crucial for both activity and selectivity. Maxima in both activity and selectivity were observed for alkali/Fe ratios in the region 1.2−1.7. A further increase in activity without any loss in selectivity was obtained by adjusting the calcination temperature to 783 K. The conversion of PO was used as a tool to measure the product stability and a minimum reaction rate was also found for alkali/Fe ratios in the region 1.2−1.7. The promoter is responsible for the formation of active centers and it reduces surface acidity which leads to an increased stability of PO through the inhibition of the consecutive conversion. Maximum selectivities to PO of about 40% at 5−10% conversion were achieved at moderate reaction temperatures of 648 K. Because of parallel and consecutive formation of carbonaceous deposits on the catalyst, the catalyst deactivated within 2 h of operation to a remaining activity of around 40%. Neglecting the carbonaceous deposits as a reaction product and considering only the vapor phase products, PO selectivity is more than 75% at 5−10% propene conversion. The attempt to slow down the deactivation through the addition of supplementary gases (H2, O2, NH3, H2O) was partially successful, but unfortunately this is always accompanied by lower PO selectivity. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie901342t Exemplaires
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Titre : Assessment of CFD−VOF method for trickle-bed reactor modeling in the catalytic wet oxidation of phenolic wastewaters Type de document : texte imprimé Auteurs : Rodrigo J. G. Lopes, Auteur ; Rosa M. Quinta-Ferreira, Auteur Année de publication : 2010 Article en page(s) : pp. 2638–2648 Note générale : Industrial Chemistry Langues : Anglais (eng) Mots-clés : Assessment CFD− VOF Trickle Bed Reactor Modeling Catalytic Wet Oxidation Phenolic Wastewaters Résumé : A multiphase volume of fluid (VOF) model was developed to provide a more detailed understanding of the transient behavior of a laboratory-scale trickle-bed reactor. The gas−liquid flow through a catalytic bed of spherical particles was used to compute velocity field and liquid volume fraction distributions considering interfacial phenomena as well as surface tension effects. The computational model was used to simulate the catalytic wet air oxidation of a phenolic model solution in the multiphase reactor. Several runs were carried out under unsteady-state operation to evaluate the dynamic performance addressing the total organic carbon concentration and temperature profiles. In all runs, some level of backmixing was predicted, being lower at high operating temperatures. These axial concentration profiles were then correlated with the radial ones revealing a poor radial mixing for the simulated flow regime, namely, at the hot spots. The influence of the operating temperature on the thermal profiles illustrated the existence of such hot spots located in the first quarter of the axial coordinate with an intensity about 6% higher than the inlet and wall temperatures. The transient radial temperature profiles corresponding to the hot spot showed the same intensity as was found for the axial thermal profiles, indicating the existence of considerable radial gradients that sustained the poor radial mixing in downflow operating mode. Despite the qualitative differences attained for the shapes of the thermal profiles, one should bear in mind that the maximum difference between the computed results and experimental data was lower than 1.5%, which reinforces the validation of the computational fluid dynamics (CFD) approach at reacting flow conditions. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie901412x
in Industrial & engineering chemistry research > Vol. 49 N° 6 (Mars 2010) . - pp. 2638–2648[article] Assessment of CFD−VOF method for trickle-bed reactor modeling in the catalytic wet oxidation of phenolic wastewaters [texte imprimé] / Rodrigo J. G. Lopes, Auteur ; Rosa M. Quinta-Ferreira, Auteur . - 2010 . - pp. 2638–2648.
Industrial Chemistry
Langues : Anglais (eng)
in Industrial & engineering chemistry research > Vol. 49 N° 6 (Mars 2010) . - pp. 2638–2648
Mots-clés : Assessment CFD− VOF Trickle Bed Reactor Modeling Catalytic Wet Oxidation Phenolic Wastewaters Résumé : A multiphase volume of fluid (VOF) model was developed to provide a more detailed understanding of the transient behavior of a laboratory-scale trickle-bed reactor. The gas−liquid flow through a catalytic bed of spherical particles was used to compute velocity field and liquid volume fraction distributions considering interfacial phenomena as well as surface tension effects. The computational model was used to simulate the catalytic wet air oxidation of a phenolic model solution in the multiphase reactor. Several runs were carried out under unsteady-state operation to evaluate the dynamic performance addressing the total organic carbon concentration and temperature profiles. In all runs, some level of backmixing was predicted, being lower at high operating temperatures. These axial concentration profiles were then correlated with the radial ones revealing a poor radial mixing for the simulated flow regime, namely, at the hot spots. The influence of the operating temperature on the thermal profiles illustrated the existence of such hot spots located in the first quarter of the axial coordinate with an intensity about 6% higher than the inlet and wall temperatures. The transient radial temperature profiles corresponding to the hot spot showed the same intensity as was found for the axial thermal profiles, indicating the existence of considerable radial gradients that sustained the poor radial mixing in downflow operating mode. Despite the qualitative differences attained for the shapes of the thermal profiles, one should bear in mind that the maximum difference between the computed results and experimental data was lower than 1.5%, which reinforces the validation of the computational fluid dynamics (CFD) approach at reacting flow conditions. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie901412x Exemplaires
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Titre : Drying of supported catalysts : a comparison of model predictions and experimental measurements of metal profiles Type de document : texte imprimé Auteurs : Xue Liu, Auteur ; Johannes G. Khinast, Auteur ; Benjamin J. Glasser, Auteur Année de publication : 2010 Article en page(s) : pp. 2649–2657 Note générale : Industrial Chemistry Langues : Anglais (eng) Mots-clés : Drying of Supported Catalysts Comparison Predictions Experimental Measurements Metal Profiles Résumé : Supported metal catalysts are used in many industrial applications. Experiments have shown that drying may significantly impact the metal distribution within the support. Therefore we need to have a fundamental understanding of drying. In this work, a theoretical model is established to predict the drying process, and the model predictions are compared with experimental measurements of a nickel/alumina system. It is found that egg-shell profiles can be enhanced by increasing the drying temperature or the initial metal concentration if the metal loading is low. For high metal loadings, nearly uniform profiles are observed after drying. We have also investigated how breakage of the liquid film inside the pores of the support can affect the metal distribution during drying. It was found that film-breakage has a significant impact on the metal distribution, and it is important to correctly capture film-breakage in the model in order to get good experimental agreement. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie9014606
in Industrial & engineering chemistry research > Vol. 49 N° 6 (Mars 2010) . - pp. 2649–2657[article] Drying of supported catalysts : a comparison of model predictions and experimental measurements of metal profiles [texte imprimé] / Xue Liu, Auteur ; Johannes G. Khinast, Auteur ; Benjamin J. Glasser, Auteur . - 2010 . - pp. 2649–2657.
Industrial Chemistry
Langues : Anglais (eng)
in Industrial & engineering chemistry research > Vol. 49 N° 6 (Mars 2010) . - pp. 2649–2657
Mots-clés : Drying of Supported Catalysts Comparison Predictions Experimental Measurements Metal Profiles Résumé : Supported metal catalysts are used in many industrial applications. Experiments have shown that drying may significantly impact the metal distribution within the support. Therefore we need to have a fundamental understanding of drying. In this work, a theoretical model is established to predict the drying process, and the model predictions are compared with experimental measurements of a nickel/alumina system. It is found that egg-shell profiles can be enhanced by increasing the drying temperature or the initial metal concentration if the metal loading is low. For high metal loadings, nearly uniform profiles are observed after drying. We have also investigated how breakage of the liquid film inside the pores of the support can affect the metal distribution during drying. It was found that film-breakage has a significant impact on the metal distribution, and it is important to correctly capture film-breakage in the model in order to get good experimental agreement. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie9014606 Exemplaires
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Titre : Biomass screening for the production of furfural via thermal decomposition Type de document : texte imprimé Auteurs : C. Di Blasi, Auteur ; C. Branca, Auteur ; A. Galgano, Auteur Année de publication : 2010 Article en page(s) : pp. 2658–2671 Note générale : Industrial Chemistry Langues : Anglais (eng) Mots-clés : Biomass Screening Production Furfural Thermal Decomposition Résumé : Packed-bed pyrolysis (heating temperature 800 K) is studied of beech and fir wood, several agro-industrial residues (corn cobs and stalks, olive husks, wheat straw, hazelnut and almond shells, orange peels, grape residues, artichoke stems, brewer’s spent grain, and pruning cuts from cherry, olive, vine, and poplar trees) and cellulose, aimed at determining the potentially most promising feedstock for the production of furfural. Parameters associated with conversion dynamics are mainly affected by the packed-bed density (0.1−1.1 g/cm3) whereas products mainly depend upon the feedstock chemical composition. In particular, the yields of condensable organic products increase with the holocellulose content (10−85%) up to 25−40% (dry sample mass basis). The higher yields of furfural (dry organics mass basis), in the range 2−0.8%, are obtained from feedstocks with significant contents of cellulose/pentoses (corn cobs, almond shells, hardwoods such as beech, cherry, olive, and poplar woods, orange peels, corn stalks, and hazelnut shells), while interesting quantities (approximately 1−0.4%) of 2(5H)-furanone are observed in all cases. As expected, the highest yields of hydroxyacetaldehyde and levoglucosan (about 8 and 3%) are produced from fir wood. On the other hand, some agro-industrial residues (hazelnut and almond shells and olive husks), apart from acetic acid, also produce high yields of phenolic compounds. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie901731u
in Industrial & engineering chemistry research > Vol. 49 N° 6 (Mars 2010) . - pp. 2658–2671[article] Biomass screening for the production of furfural via thermal decomposition [texte imprimé] / C. Di Blasi, Auteur ; C. Branca, Auteur ; A. Galgano, Auteur . - 2010 . - pp. 2658–2671.
Industrial Chemistry
Langues : Anglais (eng)
in Industrial & engineering chemistry research > Vol. 49 N° 6 (Mars 2010) . - pp. 2658–2671
Mots-clés : Biomass Screening Production Furfural Thermal Decomposition Résumé : Packed-bed pyrolysis (heating temperature 800 K) is studied of beech and fir wood, several agro-industrial residues (corn cobs and stalks, olive husks, wheat straw, hazelnut and almond shells, orange peels, grape residues, artichoke stems, brewer’s spent grain, and pruning cuts from cherry, olive, vine, and poplar trees) and cellulose, aimed at determining the potentially most promising feedstock for the production of furfural. Parameters associated with conversion dynamics are mainly affected by the packed-bed density (0.1−1.1 g/cm3) whereas products mainly depend upon the feedstock chemical composition. In particular, the yields of condensable organic products increase with the holocellulose content (10−85%) up to 25−40% (dry sample mass basis). The higher yields of furfural (dry organics mass basis), in the range 2−0.8%, are obtained from feedstocks with significant contents of cellulose/pentoses (corn cobs, almond shells, hardwoods such as beech, cherry, olive, and poplar woods, orange peels, corn stalks, and hazelnut shells), while interesting quantities (approximately 1−0.4%) of 2(5H)-furanone are observed in all cases. As expected, the highest yields of hydroxyacetaldehyde and levoglucosan (about 8 and 3%) are produced from fir wood. On the other hand, some agro-industrial residues (hazelnut and almond shells and olive husks), apart from acetic acid, also produce high yields of phenolic compounds. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie901731u Exemplaires
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Titre : High-temperature reaction in the freeboard region above a bubbling fluidized bed Type de document : texte imprimé Auteurs : Miloslav Hartman, Auteur ; Otakar Trnka, Auteur ; Michael Pohořelý, Auteur Année de publication : 2010 Article en page(s) : pp.2672–2680 Note générale : Industrial Chemistry Langues : Anglais (eng) Mots-clés : Temperature Freeboard Fluidized Bed Résumé : A plug flow model is presented for the oxidation of hazardous carbon monoxide into inert carbon dioxide taking place in the freeboard region above a freely bubbling fluidized reactor. The extent of the reaction in oxygen- and water vapor-bearing flue gas is described as a function of the fraction of solids ejected into the freeboard from the bed surface, the relative throughput, the gas density, and the global rate of reaction. Experimental measurements were conducted to determine the axial concentration profiles of carbon monoxide and other species throughout the freeboard. Steady-state measurements were carried out in an electrically heated reactor with an inner diameter of 9.36 cm above a gently fluidized bed of heat-resistant ceramsite particles in which a precursive liguid fuel (isopropanol) was burned. The global burnout reaction is assumed to be first order in carbon monoxide and one-half order with respect to oxygen and water vapor. The rate parameters for CO and O2 reacting in the freeboard were determined from the measured concentration profiles. The numeric solutions of the model equations outline the possibilities and limitations for the performance of an afterburner chamber. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie901760f
in Industrial & engineering chemistry research > Vol. 49 N° 6 (Mars 2010) . - pp.2672–2680[article] High-temperature reaction in the freeboard region above a bubbling fluidized bed [texte imprimé] / Miloslav Hartman, Auteur ; Otakar Trnka, Auteur ; Michael Pohořelý, Auteur . - 2010 . - pp.2672–2680.
Industrial Chemistry
Langues : Anglais (eng)
in Industrial & engineering chemistry research > Vol. 49 N° 6 (Mars 2010) . - pp.2672–2680
Mots-clés : Temperature Freeboard Fluidized Bed Résumé : A plug flow model is presented for the oxidation of hazardous carbon monoxide into inert carbon dioxide taking place in the freeboard region above a freely bubbling fluidized reactor. The extent of the reaction in oxygen- and water vapor-bearing flue gas is described as a function of the fraction of solids ejected into the freeboard from the bed surface, the relative throughput, the gas density, and the global rate of reaction. Experimental measurements were conducted to determine the axial concentration profiles of carbon monoxide and other species throughout the freeboard. Steady-state measurements were carried out in an electrically heated reactor with an inner diameter of 9.36 cm above a gently fluidized bed of heat-resistant ceramsite particles in which a precursive liguid fuel (isopropanol) was burned. The global burnout reaction is assumed to be first order in carbon monoxide and one-half order with respect to oxygen and water vapor. The rate parameters for CO and O2 reacting in the freeboard were determined from the measured concentration profiles. The numeric solutions of the model equations outline the possibilities and limitations for the performance of an afterburner chamber. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie901760f Exemplaires
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Titre : Phase-transfer catalysis in segmented flow in a microchannel : fluidic control of selectivity and productivity Type de document : texte imprimé Auteurs : Jovan Jovanović, Auteur ; Evgeny V. Rebrov, Auteur ; T. A. (Xander) Nijhuis, Auteur Année de publication : 2010 Article en page(s) : pp. 2681–2687 Note générale : Industrial Chemistry Langues : Anglais (eng) Mots-clés : Catalysis in Segmented Flow Microchannel Fluidic Selectivity Productivity Résumé : Precise control over the interfacial area of aqueous and organic slugs in segmented flow in a microchannel reactor provides an attractive means to optimize the yield and productivity of a phase-transfer-catalyzed reaction. Herein, we report the selective alkylation of phenylacetonitrile to the monoalkylated product in a microchannel of 250-μm internal diameter operated in a continuous and solvent-free manner in the slug-flow regime. The conversion of phenylacetonitrile increased from 40% to 99% as a result of a 97% larger slug surface-to-volume ratio when the volumetric aqueous-to-organic phase flow ratio was raised from 1.0 to 6.1 at the same residence time. The larger surface-to-volume ratio significantly promoted catalyst phase transfer but decreased selectivity because of the simultaneous increase of the rate of the consecutive reaction to the dialkylated product. There exists an optimum flow ratio with a maximum productivity. Conversion and selectivity in the microchannel reactor were both found to be significantly larger than in a stirred reactor. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie9017918
in Industrial & engineering chemistry research > Vol. 49 N° 6 (Mars 2010) . - pp. 2681–2687[article] Phase-transfer catalysis in segmented flow in a microchannel : fluidic control of selectivity and productivity [texte imprimé] / Jovan Jovanović, Auteur ; Evgeny V. Rebrov, Auteur ; T. A. (Xander) Nijhuis, Auteur . - 2010 . - pp. 2681–2687.
Industrial Chemistry
Langues : Anglais (eng)
in Industrial & engineering chemistry research > Vol. 49 N° 6 (Mars 2010) . - pp. 2681–2687
Mots-clés : Catalysis in Segmented Flow Microchannel Fluidic Selectivity Productivity Résumé : Precise control over the interfacial area of aqueous and organic slugs in segmented flow in a microchannel reactor provides an attractive means to optimize the yield and productivity of a phase-transfer-catalyzed reaction. Herein, we report the selective alkylation of phenylacetonitrile to the monoalkylated product in a microchannel of 250-μm internal diameter operated in a continuous and solvent-free manner in the slug-flow regime. The conversion of phenylacetonitrile increased from 40% to 99% as a result of a 97% larger slug surface-to-volume ratio when the volumetric aqueous-to-organic phase flow ratio was raised from 1.0 to 6.1 at the same residence time. The larger surface-to-volume ratio significantly promoted catalyst phase transfer but decreased selectivity because of the simultaneous increase of the rate of the consecutive reaction to the dialkylated product. There exists an optimum flow ratio with a maximum productivity. Conversion and selectivity in the microchannel reactor were both found to be significantly larger than in a stirred reactor. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie9017918 Exemplaires
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Titre : Kinetics of aldehyde oxidation by chlorous acid Type de document : texte imprimé Auteurs : Tuula Lehtimaa, Auteur ; Susanna Kuitunen, Auteur ; Ville Tarvo, Auteur Année de publication : 2010 Article en page(s) : pp. 2688–2693 Note générale : industrial Chemistry Langues : Anglais (eng) Mots-clés : Kinetics Aldehyde Oxidation Chlorous Acid Résumé : Chlorous acid is known to react with aldehydes. This study investigated the oxidation kinetics of different aldehydes by chlorous acid. Reaction rates with chlorous acid at 25 °C were obtained for formaldehyde (11.0 M−1 s−1), vanillin (0.59 M−1 s−1), veratraldehyde (1.00 M−1 s−1), benzaldehyde (5.6 M−1 s−1), glucose (3.39 × 10−3 M−1 s−1), glycolaldehyde (39.0 M−1 s−1), and 5-formyl-2-furancarboxylic acid (5.2 M−1 s−1). The activation energies varied between 26 and 63 kJ/mol. The rate-determining step was shown to be the addition of chlorous acid to the aldehyde structure. The practical significance of the Cl(III) reaction with aldehyde structures in chlorine dioxide bleaching was discussed. It was concluded that various aldehydes present in cellulosic pulp are at least partly responsible for the consumption of Cl(III) in chlorine dioxide bleaching. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie9018885
in Industrial & engineering chemistry research > Vol. 49 N° 6 (Mars 2010) . - pp. 2688–2693[article] Kinetics of aldehyde oxidation by chlorous acid [texte imprimé] / Tuula Lehtimaa, Auteur ; Susanna Kuitunen, Auteur ; Ville Tarvo, Auteur . - 2010 . - pp. 2688–2693.
industrial Chemistry
Langues : Anglais (eng)
in Industrial & engineering chemistry research > Vol. 49 N° 6 (Mars 2010) . - pp. 2688–2693
Mots-clés : Kinetics Aldehyde Oxidation Chlorous Acid Résumé : Chlorous acid is known to react with aldehydes. This study investigated the oxidation kinetics of different aldehydes by chlorous acid. Reaction rates with chlorous acid at 25 °C were obtained for formaldehyde (11.0 M−1 s−1), vanillin (0.59 M−1 s−1), veratraldehyde (1.00 M−1 s−1), benzaldehyde (5.6 M−1 s−1), glucose (3.39 × 10−3 M−1 s−1), glycolaldehyde (39.0 M−1 s−1), and 5-formyl-2-furancarboxylic acid (5.2 M−1 s−1). The activation energies varied between 26 and 63 kJ/mol. The rate-determining step was shown to be the addition of chlorous acid to the aldehyde structure. The practical significance of the Cl(III) reaction with aldehyde structures in chlorine dioxide bleaching was discussed. It was concluded that various aldehydes present in cellulosic pulp are at least partly responsible for the consumption of Cl(III) in chlorine dioxide bleaching. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie9018885 Exemplaires
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Titre : Effect of metals on supercritical water gasification of cellulose and lignin Type de document : texte imprimé Auteurs : Fernando L. P. Resende, Auteur ; Phillip E. Savage, Auteur Année de publication : 2010 Article en page(s) : pp. 2694–2700 Note générale : Idustrial Chemistry Langues : Anglais (eng) Mots-clés : Metals Supercritical Water Gasification Cellulose Lignin Résumé : We gasified cellulose and lignin in supercritical water, using quartz reactors, and quantified the catalytic effect of metals by adding them to these reactors in different forms. We used nickel, iron, copper, zinc, and zirconium wires, ruthenium powder, and Raney nickel slurry. The presence of metals was more likely to increase gas yields to a measurable extent when the catalyst surface area/biomass weight ratio was at least 15 mm2/mg (5.0 wt % biomass loading in our experiments). Nickel and copper typically provided higher gas yields at 5.0 wt % loading, and nickel provided the highest H2 yields at 1.0 wt % loading. SCWG at 500 °C with nickel at 240 mm2/mg generated 16 mmol/g of H2 from cellulose. CH4 yields were not strongly influenced by the presence of metals. With nickel wires in the reactor, gas with about 40−50% of the energy content in the original biomass was produced from cellulose and lignin. All of the metals tested except copper produced H2 from water when exposed to SCWG conditions with no biomass. It is important that this background H2 formation be accounted for when interpreting results from SCWG experiments in the presence of metals. Exposure of nickel wires to supercritical water did not reduce their activity for H2 production. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie901928f
in Industrial & engineering chemistry research > Vol. 49 N° 6 (Mars 2010) . - pp. 2694–2700[article] Effect of metals on supercritical water gasification of cellulose and lignin [texte imprimé] / Fernando L. P. Resende, Auteur ; Phillip E. Savage, Auteur . - 2010 . - pp. 2694–2700.
Idustrial Chemistry
Langues : Anglais (eng)
in Industrial & engineering chemistry research > Vol. 49 N° 6 (Mars 2010) . - pp. 2694–2700
Mots-clés : Metals Supercritical Water Gasification Cellulose Lignin Résumé : We gasified cellulose and lignin in supercritical water, using quartz reactors, and quantified the catalytic effect of metals by adding them to these reactors in different forms. We used nickel, iron, copper, zinc, and zirconium wires, ruthenium powder, and Raney nickel slurry. The presence of metals was more likely to increase gas yields to a measurable extent when the catalyst surface area/biomass weight ratio was at least 15 mm2/mg (5.0 wt % biomass loading in our experiments). Nickel and copper typically provided higher gas yields at 5.0 wt % loading, and nickel provided the highest H2 yields at 1.0 wt % loading. SCWG at 500 °C with nickel at 240 mm2/mg generated 16 mmol/g of H2 from cellulose. CH4 yields were not strongly influenced by the presence of metals. With nickel wires in the reactor, gas with about 40−50% of the energy content in the original biomass was produced from cellulose and lignin. All of the metals tested except copper produced H2 from water when exposed to SCWG conditions with no biomass. It is important that this background H2 formation be accounted for when interpreting results from SCWG experiments in the presence of metals. Exposure of nickel wires to supercritical water did not reduce their activity for H2 production. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie901928f Exemplaires
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Titre : Behavior of CaTiO3/nano-CaO as a CO2 reactive adsorbent Type de document : texte imprimé Auteurs : S. F. Wu, Auteur ; Y. Q. Zhu, Auteur Année de publication : 2010 Article en page(s) : pp. 2701–2706 Note générale : Industrial Chemistry Langues : Anglais (eng) Mots-clés : Behavior CaTiO3/Nano-CaO CO2 Adsorbent Résumé : his study focuses on the preparation of a CaTiO3-coated nano-CaO-based CO2 adsorbent (CaTiO3/nano-CaO) for the improvement of sorption properties. The CaTiO3-coated nano-CaO adsorbent was prepared by forming Ti(OH)4 from the hydrolysis of titanium alkoxide in a nano-CaCO3 suspended solution. The resulting Ti(OH)4-coated nano-CaCO3 was then heated and calcined. Test results from transmission electron microscopy and scanning electron microscopy with energy dispersive X-ray spectroscopy show that an obvious film of TiO2 was formed on the surface of nano-CaCO3 after heating. X-ray diffraction analysis also showed that the nano-CaTiO3 layer was formed at 750 °C, a calcination temperature that causes the reaction of TiO2 with nano-CaO. The cyclic tests of reactive sorption capacity were conducted in a thermogravimetric analyzer under the following conditions: 0.02 MPa CO2 partial pressure, carbonation temperature of 600 °C, and calcination temperature of 750 °C. Test results showed that CaTiO3 coated onto the nano-CaO caused a significant improvement in the durability of the capacity for reactive sorption. Nano-CaO that had an optimum content of 10 wt % TiO2 showed significantly stable CO2 reactive sorption capacity (5.3 mol/kg) after 40 cyclic carbonation−calcination runs compared to the reactive sorption capacity of CaO without TiO2 coating (3.7 mol/kg). ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie900900r
in Industrial & engineering chemistry research > Vol. 49 N° 6 (Mars 2010) . - pp. 2701–2706[article] Behavior of CaTiO3/nano-CaO as a CO2 reactive adsorbent [texte imprimé] / S. F. Wu, Auteur ; Y. Q. Zhu, Auteur . - 2010 . - pp. 2701–2706.
Industrial Chemistry
Langues : Anglais (eng)
in Industrial & engineering chemistry research > Vol. 49 N° 6 (Mars 2010) . - pp. 2701–2706
Mots-clés : Behavior CaTiO3/Nano-CaO CO2 Adsorbent Résumé : his study focuses on the preparation of a CaTiO3-coated nano-CaO-based CO2 adsorbent (CaTiO3/nano-CaO) for the improvement of sorption properties. The CaTiO3-coated nano-CaO adsorbent was prepared by forming Ti(OH)4 from the hydrolysis of titanium alkoxide in a nano-CaCO3 suspended solution. The resulting Ti(OH)4-coated nano-CaCO3 was then heated and calcined. Test results from transmission electron microscopy and scanning electron microscopy with energy dispersive X-ray spectroscopy show that an obvious film of TiO2 was formed on the surface of nano-CaCO3 after heating. X-ray diffraction analysis also showed that the nano-CaTiO3 layer was formed at 750 °C, a calcination temperature that causes the reaction of TiO2 with nano-CaO. The cyclic tests of reactive sorption capacity were conducted in a thermogravimetric analyzer under the following conditions: 0.02 MPa CO2 partial pressure, carbonation temperature of 600 °C, and calcination temperature of 750 °C. Test results showed that CaTiO3 coated onto the nano-CaO caused a significant improvement in the durability of the capacity for reactive sorption. Nano-CaO that had an optimum content of 10 wt % TiO2 showed significantly stable CO2 reactive sorption capacity (5.3 mol/kg) after 40 cyclic carbonation−calcination runs compared to the reactive sorption capacity of CaO without TiO2 coating (3.7 mol/kg). ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie900900r Exemplaires
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Titre : Synthesis of gold nanoparticles coated with polystyrene-block-poly(n-isopropylacrylamide) and their thermoresponsive ultraviolet−visible absorbance Type de document : texte imprimé Auteurs : Yunxia Liu, Auteur ; Weixia Tu, Auteur ; Dapeng Cao, Auteur Année de publication : 2010 Article en page(s) : pp. 2707–2715 Note générale : Industrial Chemistry Langues : Anglais (eng) Mots-clés : Gold nanoparticles Polystyrene Poly N-isopropylacrylamide Thermoresponsive Ultraviolet Visible Absorbance Résumé : Poly(styrene-b-N-isopropylacrylamide) (PSt-b-PNIPAM) with a narrow molecular weight distribution is prepared by reversible addition−fragmentation transfer radical polymerization. The dithioester group at the chain end of PSt-b-PNIPAM is converted into thiol terminal group by LiB(C2H5)3H. Gold nanoparticles and the PSt-b-PNIPAM interact via the terminal thiol group (-SH). The size of the gold nanoparticles coated with copolymers can be easily manipulated by adjusting the molar ratio of HAuCl4/PSt-b-PNIPAM. Interestingly, the thermosensitive gold nanoparticles exhibit a sharp and reversible transparent−opaque transition between 25 and 40 °C. Moreover, the transition change is sensitive to the size of the gold nanoparticles and the macromolecular weight of the copolymer. The maximum wavelength of the surface plasmon band and the hydrodynamic size of the PSt-b-PNIPAM-Au micelles are sensitive to temperature, pH, and salt concentration. A considerable red shift from 524 to 534 nm in the plasmon band is observed in 0.9% NaCl aqueous solution, but no appreciable change in the band is observed in pure water when the temperature increases from 25 to 40 °C. With a decrease of the pH of the solution, the maximum wavelength of the surface plasmon band exhibits a red shift (from 520 to 534 nm). In addition, dynamic light scatting (DLS) reveals that the hydrodynamic size of coated gold nanoparticles exhibits a small change under alkaline and neutral (pH = 7) conditions, but it gives a pronounced change in the acidic condition (from 350 to 280 nm) when the temperature increases from 25 to 40 °C. Furthermore, the UV−vis absorption spectrum clearly shows that the red shift of the thermosensitive gold nanoparticles is reversible. Note de contenu : Bibiogr. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie901143p
in Industrial & engineering chemistry research > Vol. 49 N° 6 (Mars 2010) . - pp. 2707–2715[article] Synthesis of gold nanoparticles coated with polystyrene-block-poly(n-isopropylacrylamide) and their thermoresponsive ultraviolet−visible absorbance [texte imprimé] / Yunxia Liu, Auteur ; Weixia Tu, Auteur ; Dapeng Cao, Auteur . - 2010 . - pp. 2707–2715.
Industrial Chemistry
Langues : Anglais (eng)
in Industrial & engineering chemistry research > Vol. 49 N° 6 (Mars 2010) . - pp. 2707–2715
Mots-clés : Gold nanoparticles Polystyrene Poly N-isopropylacrylamide Thermoresponsive Ultraviolet Visible Absorbance Résumé : Poly(styrene-b-N-isopropylacrylamide) (PSt-b-PNIPAM) with a narrow molecular weight distribution is prepared by reversible addition−fragmentation transfer radical polymerization. The dithioester group at the chain end of PSt-b-PNIPAM is converted into thiol terminal group by LiB(C2H5)3H. Gold nanoparticles and the PSt-b-PNIPAM interact via the terminal thiol group (-SH). The size of the gold nanoparticles coated with copolymers can be easily manipulated by adjusting the molar ratio of HAuCl4/PSt-b-PNIPAM. Interestingly, the thermosensitive gold nanoparticles exhibit a sharp and reversible transparent−opaque transition between 25 and 40 °C. Moreover, the transition change is sensitive to the size of the gold nanoparticles and the macromolecular weight of the copolymer. The maximum wavelength of the surface plasmon band and the hydrodynamic size of the PSt-b-PNIPAM-Au micelles are sensitive to temperature, pH, and salt concentration. A considerable red shift from 524 to 534 nm in the plasmon band is observed in 0.9% NaCl aqueous solution, but no appreciable change in the band is observed in pure water when the temperature increases from 25 to 40 °C. With a decrease of the pH of the solution, the maximum wavelength of the surface plasmon band exhibits a red shift (from 520 to 534 nm). In addition, dynamic light scatting (DLS) reveals that the hydrodynamic size of coated gold nanoparticles exhibits a small change under alkaline and neutral (pH = 7) conditions, but it gives a pronounced change in the acidic condition (from 350 to 280 nm) when the temperature increases from 25 to 40 °C. Furthermore, the UV−vis absorption spectrum clearly shows that the red shift of the thermosensitive gold nanoparticles is reversible. Note de contenu : Bibiogr. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie901143p Exemplaires
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Titre : Mercury removal from aqueous solution using coke-derived sulfur-impregnated activated carbons Type de document : texte imprimé Auteurs : Jenny H. Cai, Auteur ; Charles Q. Jia, Auteur Année de publication : 2010 Article en page(s) : pp. 2716–2721 Note générale : Industrial Chemistry Langues : Anglais (eng) Mots-clés : Mercury Removal Aqueous Solution Coke-Derived Sulfur Impregnated Activated Carbons Résumé : Sulfur-impregnated activated carbons (SIACs) produced from oil-sands fluid coke by KOH−SO2 activation were applied to remove mercury ions from aqueous solutions. A pseudo-first-order rate expression can describe the Hg2+ adsorption behavior of SIACs produced in this study. The rate constants were found to be 0.01−0.102 min−1. The Hg2+ adsorption capacities of the examined SIACs ranged from 43 to 72 mg/g, which were comparable to those reported in the literature (35−100 mg/g) and that of a commercial SIAC (41 mg/g). The adsorption capacity increased with increasing specific surface area (SBET) of the SIACs, and a positive correlation was found between the SBET-normalized adsorption capacity and the total sulfur content of the SIACs. Elemental sulfur, disulfide, and thiophene seemed particularly effective in Hg2+ adsorption, as SIACs with these sulfur compounds showed higher adsorption capacities in general. Note de contenu : Bibiogr. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie901194r
in Industrial & engineering chemistry research > Vol. 49 N° 6 (Mars 2010) . - pp. 2716–2721[article] Mercury removal from aqueous solution using coke-derived sulfur-impregnated activated carbons [texte imprimé] / Jenny H. Cai, Auteur ; Charles Q. Jia, Auteur . - 2010 . - pp. 2716–2721.
Industrial Chemistry
Langues : Anglais (eng)
in Industrial & engineering chemistry research > Vol. 49 N° 6 (Mars 2010) . - pp. 2716–2721
Mots-clés : Mercury Removal Aqueous Solution Coke-Derived Sulfur Impregnated Activated Carbons Résumé : Sulfur-impregnated activated carbons (SIACs) produced from oil-sands fluid coke by KOH−SO2 activation were applied to remove mercury ions from aqueous solutions. A pseudo-first-order rate expression can describe the Hg2+ adsorption behavior of SIACs produced in this study. The rate constants were found to be 0.01−0.102 min−1. The Hg2+ adsorption capacities of the examined SIACs ranged from 43 to 72 mg/g, which were comparable to those reported in the literature (35−100 mg/g) and that of a commercial SIAC (41 mg/g). The adsorption capacity increased with increasing specific surface area (SBET) of the SIACs, and a positive correlation was found between the SBET-normalized adsorption capacity and the total sulfur content of the SIACs. Elemental sulfur, disulfide, and thiophene seemed particularly effective in Hg2+ adsorption, as SIACs with these sulfur compounds showed higher adsorption capacities in general. Note de contenu : Bibiogr. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie901194r Exemplaires
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Titre : Analysis of carbonaceous solid deposits from thermal oxidative stressing of jet-a fuel on iron- and nickel-based alloy surfaces Type de document : texte imprimé Auteurs : Arun Ram Mohan, Auteur ; Semih Eser, Auteur Année de publication : 2010 Article en page(s) : pp. 2722–2730 Note générale : Industrial Chemistry Langues : Anglais (eng) Mots-clés : Carbonaceous Solid Deposits Thermal Oxidative Jet-A Fuel Nickel Surfaces Based Alloy Résumé : Thermal stressing of Jet-A was conducted in a flow reactor on iron- and nickel-based metal surfaces at a fuel flow rate of 1 mL/min for 5 h at a wall temperature of 350 °C and 3.5 MPa (500 psig) so that both liquid-phase autoxidation and thermal decomposition of autoxidation products contribute to the formation of carbonaceous deposits. The deposits produced were characterized by field emission scanning electron microscopy (FESEM) and temperature programmed oxidation (TPO). The effect of metal surface on deposit formation increases in the following order: AISI316 Note de contenu : Bibiogr. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie901283r
in Industrial & engineering chemistry research > Vol. 49 N° 6 (Mars 2010) . - pp. 2722–2730[article] Analysis of carbonaceous solid deposits from thermal oxidative stressing of jet-a fuel on iron- and nickel-based alloy surfaces [texte imprimé] / Arun Ram Mohan, Auteur ; Semih Eser, Auteur . - 2010 . - pp. 2722–2730.
Industrial Chemistry
Langues : Anglais (eng)
in Industrial & engineering chemistry research > Vol. 49 N° 6 (Mars 2010) . - pp. 2722–2730
Mots-clés : Carbonaceous Solid Deposits Thermal Oxidative Jet-A Fuel Nickel Surfaces Based Alloy Résumé : Thermal stressing of Jet-A was conducted in a flow reactor on iron- and nickel-based metal surfaces at a fuel flow rate of 1 mL/min for 5 h at a wall temperature of 350 °C and 3.5 MPa (500 psig) so that both liquid-phase autoxidation and thermal decomposition of autoxidation products contribute to the formation of carbonaceous deposits. The deposits produced were characterized by field emission scanning electron microscopy (FESEM) and temperature programmed oxidation (TPO). The effect of metal surface on deposit formation increases in the following order: AISI316 Note de contenu : Bibiogr. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie901283r Exemplaires
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Titre : Photoresist derived electrospun carbon nanofibers with tunable morphology and surface properties Type de document : texte imprimé Auteurs : Chandra S. Sharma, Auteur ; Rajesh Vasita, Auteur ; Devendra K. Upadhyay, Auteur Année de publication : 2010 Article en page(s) : pp.2731–2739 Note générale : Industrial Chemistry Langues : Anglais (eng) Mots-clés : Photoresist Derived Electrospun Carbon Nanofibers Tunable Morphology Surface Properties Résumé : A new precursor, SU-8, which is a negative photoresist, was electrospun to produce ultrafine polymeric fibers with a wide range of morphology and wettability characteristics. Electrospun nanofibers of SU-8 were pyrolyzed at 1173 K in an inert atmosphere to give carbon nanofibers. A set of parameters, including electric potential, distance between source and collector, polymer flow rate, and polymer concentration, was optimized for high-viscosity SU-8 photoresist to synthesize long continuous carbon fibers having diameters in the range of 120−600 nm. However, for the same conditions, medium- and lower-viscosity SU-8 yielded beaded fibers and isolated beads, respectively. The wettability of the carbon web was significantly influenced by its surface morphology, as shown by water contact angle measurements. These SU-8-derived carbon nanostructures with tunable surface properties and morphologies could be especially suitable for integration with photoresist-based carbon-MEMS to produce multiscale hierarchal assemblies and could be of potential use in a broad range of applications. Note de contenu : Bibiogr. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie901312j
in Industrial & engineering chemistry research > Vol. 49 N° 6 (Mars 2010) . - pp.2731–2739[article] Photoresist derived electrospun carbon nanofibers with tunable morphology and surface properties [texte imprimé] / Chandra S. Sharma, Auteur ; Rajesh Vasita, Auteur ; Devendra K. Upadhyay, Auteur . - 2010 . - pp.2731–2739.
Industrial Chemistry
Langues : Anglais (eng)
in Industrial & engineering chemistry research > Vol. 49 N° 6 (Mars 2010) . - pp.2731–2739
Mots-clés : Photoresist Derived Electrospun Carbon Nanofibers Tunable Morphology Surface Properties Résumé : A new precursor, SU-8, which is a negative photoresist, was electrospun to produce ultrafine polymeric fibers with a wide range of morphology and wettability characteristics. Electrospun nanofibers of SU-8 were pyrolyzed at 1173 K in an inert atmosphere to give carbon nanofibers. A set of parameters, including electric potential, distance between source and collector, polymer flow rate, and polymer concentration, was optimized for high-viscosity SU-8 photoresist to synthesize long continuous carbon fibers having diameters in the range of 120−600 nm. However, for the same conditions, medium- and lower-viscosity SU-8 yielded beaded fibers and isolated beads, respectively. The wettability of the carbon web was significantly influenced by its surface morphology, as shown by water contact angle measurements. These SU-8-derived carbon nanostructures with tunable surface properties and morphologies could be especially suitable for integration with photoresist-based carbon-MEMS to produce multiscale hierarchal assemblies and could be of potential use in a broad range of applications. Note de contenu : Bibiogr. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie901312j Exemplaires
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Titre : Nanostructured protective coating systems, fireproof and environmentally friendly, suitable for the protection of metallic substrates Type de document : texte imprimé Auteurs : Andrea M. Pereyra, Auteur ; Guadalupe Canosa, Auteur ; Carlos A. Giudice, Auteur Année de publication : 2010 Article en page(s) : pp. 2740–2746 Note générale : Industrial Chemistry Langues : Anglais (eng) Mots-clés : Nanostructured Protective Coating Fireproof Environmentally Friendly Metallic Substrates Résumé : The aim of this study was to formulate, develop, and determine the behavior of nanostructured protective coating systems, fireproof and environmentally friendly, suitable for the protection of metallic substrates. The results allowed concluding that the di- and tripigmented formulations based on laminar zinc, either alone or mixed with nanozinc, showed an excellent corrosion resistance when a nanostructured self-cured inorganic silicate (high silica/alkali ratio) was selected as the film forming material. Coating systems included a sealer of low permeability, which was based on the same film forming material that primers and on laminar pigments. Intumescent coatings were manufactured and then applied on the sealer; in this study, two types of products in an aqueous single package were formulated. The anticorrosive capacity was evaluated in a salt spraying (fog) chamber and in a 100% relative humidity cabinet while the performance against the fire action was determined by estimating the limiting oxygen index in the LOI cabinet, the flame advance in an inclined tunnel, and, finally, the thermal conductivity in a UL 94 flame chamber; in the last test, the degree of intumescence was also assessed. The results showed an excellent ability for corrosion controlling and, in addition, a good performance against the fire action of some of the no pollutant coating systems designed. Note de contenu : Bibiogr. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie901404s
in Industrial & engineering chemistry research > Vol. 49 N° 6 (Mars 2010) . - pp. 2740–2746[article] Nanostructured protective coating systems, fireproof and environmentally friendly, suitable for the protection of metallic substrates [texte imprimé] / Andrea M. Pereyra, Auteur ; Guadalupe Canosa, Auteur ; Carlos A. Giudice, Auteur . - 2010 . - pp. 2740–2746.
Industrial Chemistry
Langues : Anglais (eng)
in Industrial & engineering chemistry research > Vol. 49 N° 6 (Mars 2010) . - pp. 2740–2746
Mots-clés : Nanostructured Protective Coating Fireproof Environmentally Friendly Metallic Substrates Résumé : The aim of this study was to formulate, develop, and determine the behavior of nanostructured protective coating systems, fireproof and environmentally friendly, suitable for the protection of metallic substrates. The results allowed concluding that the di- and tripigmented formulations based on laminar zinc, either alone or mixed with nanozinc, showed an excellent corrosion resistance when a nanostructured self-cured inorganic silicate (high silica/alkali ratio) was selected as the film forming material. Coating systems included a sealer of low permeability, which was based on the same film forming material that primers and on laminar pigments. Intumescent coatings were manufactured and then applied on the sealer; in this study, two types of products in an aqueous single package were formulated. The anticorrosive capacity was evaluated in a salt spraying (fog) chamber and in a 100% relative humidity cabinet while the performance against the fire action was determined by estimating the limiting oxygen index in the LOI cabinet, the flame advance in an inclined tunnel, and, finally, the thermal conductivity in a UL 94 flame chamber; in the last test, the degree of intumescence was also assessed. The results showed an excellent ability for corrosion controlling and, in addition, a good performance against the fire action of some of the no pollutant coating systems designed. Note de contenu : Bibiogr. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie901404s Exemplaires
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Titre : Preparation and characterization of water-soluble single-walled carbon nanotubes by hybridization with hydroxypropyl cellulose derivatives Type de document : texte imprimé Auteurs : Qiang Yang, Auteur ; Xuejun Pan, Auteur Année de publication : 2010 Article en page(s) : pp. 2747–2751 Note générale : Industrial Chemistry Langues : Anglais (eng) Mots-clés : Characterization Water-Soluble Carbon Nanotubes Hybridization Hydroxypropyl Cellulose Résumé : Single-walled carbon nanotube (SWNT) hybrids were prepared through noncovalent functionalization with pyrene-containing hydroxypropyl cellulose derivatives (HPC-Py) that were synthesized by simple condensation and substitution reactions. The obtained SWNT hybrids were structurally characterized with UV−vis, fluorescence, ATR FT-IR, and Raman spectroscopies. The prepared SWNT hybrids were soluble in water with good storage stability, and their statistical average size was approximately 260 nm. The hybridization extent of the SWNTs was dependent on the content of pyrene moieties in HPC-Py. The hydroxypropyl cellulose attached to the surface of the SWNTs was hydrolyzable or removable by cellulases, whereas the SWNTs underwent no structural changes during the enzymatic treatment. Note de contenu : Bibiogr. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie9014149
in Industrial & engineering chemistry research > Vol. 49 N° 6 (Mars 2010) . - pp. 2747–2751[article] Preparation and characterization of water-soluble single-walled carbon nanotubes by hybridization with hydroxypropyl cellulose derivatives [texte imprimé] / Qiang Yang, Auteur ; Xuejun Pan, Auteur . - 2010 . - pp. 2747–2751.
Industrial Chemistry
Langues : Anglais (eng)
in Industrial & engineering chemistry research > Vol. 49 N° 6 (Mars 2010) . - pp. 2747–2751
Mots-clés : Characterization Water-Soluble Carbon Nanotubes Hybridization Hydroxypropyl Cellulose Résumé : Single-walled carbon nanotube (SWNT) hybrids were prepared through noncovalent functionalization with pyrene-containing hydroxypropyl cellulose derivatives (HPC-Py) that were synthesized by simple condensation and substitution reactions. The obtained SWNT hybrids were structurally characterized with UV−vis, fluorescence, ATR FT-IR, and Raman spectroscopies. The prepared SWNT hybrids were soluble in water with good storage stability, and their statistical average size was approximately 260 nm. The hybridization extent of the SWNTs was dependent on the content of pyrene moieties in HPC-Py. The hydroxypropyl cellulose attached to the surface of the SWNTs was hydrolyzable or removable by cellulases, whereas the SWNTs underwent no structural changes during the enzymatic treatment. Note de contenu : Bibiogr. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie9014149 Exemplaires
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Titre : Effective cr(VI) removal from simulated groundwater through the hydrotalcite-derived adsorbent Type de document : texte imprimé Auteurs : Yunfeng Xu, Auteur ; Jia Zhang, Auteur ; Guangren Qian, Auteur Année de publication : 2010 Article en page(s) : pp. 2752–2758 Note générale : Industrial Chemistry Langues : Anglais (eng) Mots-clés : Effective Cr(VI Removal from Groundwater Hydrotalcite Résumé : We investigated the feasibility of using calcined hydrotalcite (CHT) as the adsorbent of chromate to treat Cr(VI)-contaminated water through column tests under varied conditions. The column tests reveal that CHT can take up 34.3−44.7 mg(Cr)/g when the Cr(VI) concentration in the influent varies over a range of 50−200 mg/L (e.g., 0.96−3.85 mM) with pH 6−7 at 298 K. This uptake capacity is only reduced to 29.1 mg(Cr)/g when HCO3− (1.0 mM) and Cl− (1.0 mM) coexist in the influent. We note that the treated water is of high quality and is free of Cr(VI), with Mg and Al concentrations of Note de contenu : Bibiogr. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie901469c
in Industrial & engineering chemistry research > Vol. 49 N° 6 (Mars 2010) . - pp. 2752–2758[article] Effective cr(VI) removal from simulated groundwater through the hydrotalcite-derived adsorbent [texte imprimé] / Yunfeng Xu, Auteur ; Jia Zhang, Auteur ; Guangren Qian, Auteur . - 2010 . - pp. 2752–2758.
Industrial Chemistry
Langues : Anglais (eng)
in Industrial & engineering chemistry research > Vol. 49 N° 6 (Mars 2010) . - pp. 2752–2758
Mots-clés : Effective Cr(VI Removal from Groundwater Hydrotalcite Résumé : We investigated the feasibility of using calcined hydrotalcite (CHT) as the adsorbent of chromate to treat Cr(VI)-contaminated water through column tests under varied conditions. The column tests reveal that CHT can take up 34.3−44.7 mg(Cr)/g when the Cr(VI) concentration in the influent varies over a range of 50−200 mg/L (e.g., 0.96−3.85 mM) with pH 6−7 at 298 K. This uptake capacity is only reduced to 29.1 mg(Cr)/g when HCO3− (1.0 mM) and Cl− (1.0 mM) coexist in the influent. We note that the treated water is of high quality and is free of Cr(VI), with Mg and Al concentrations of Note de contenu : Bibiogr. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie901469c Exemplaires
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Titre : Facile sodium alginate assisted assembly of ni−al layered double hydroxide nanostructures Type de document : texte imprimé Auteurs : Hui Wang, Auteur ; Guoli Fan, Auteur ; Chen Zheng, Auteur Année de publication : 2010 Article en page(s) : pp. 2759–2767 Note générale : Industrial Chemistry Langues : Anglais (eng) Mots-clés : Facile Sodium Alginate Assembly Layered Double Hydroxide Nanostructures Résumé : Self-assembled three-dimensional Ni−Al layered double hydroxide (LDH) nanostructures have been successfully synthesized using a facile biopolymer-assisted approach in the presence of a simple, safe, and inexpensive sodium alginate biopolymer under hydrothermal conditions. The structure and morphology of LDH nanostructures obtained have been investigated by scanning electron microscopy (SEM), powder X-ray diffraction (XRD), high-resolution transmission electron microscopy (HRTEM), Fourier transform infrared spectroscopy (FT-IR), thermogravimetric and differential thermal analysis (TG-DTA), and UV−visible diffuse spectroscopy (UV−vis). Three types of pompon-like, marigold-like, and coral-like LDH nanostructures could be obtained by adjusting the synthesis parameters including hydrothermal aging time, concentration of metal ions, and reaction temperature. A possible formation mechanism for the controlled organization of primary LDH nanosheet building units into special three-dimensional nanostructures is proposed on the basis of the interaction between sodium alginate molecules and LDH crystals. Furthermore, after calcination of LDHs at 500 and 700 °C, the resulting NiO-based mixed metal oxides still maintain the three-dimensional morphology of their LDH precursors to some extent, indicative of the high thermal stability of nanostructures. The findings in this work provide a feasible approach for the morphosynthesis of LDH nanomaterials with special superstructures. Note de contenu : Bibiogr. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie901519h
in Industrial & engineering chemistry research > Vol. 49 N° 6 (Mars 2010) . - pp. 2759–2767[article] Facile sodium alginate assisted assembly of ni−al layered double hydroxide nanostructures [texte imprimé] / Hui Wang, Auteur ; Guoli Fan, Auteur ; Chen Zheng, Auteur . - 2010 . - pp. 2759–2767.
Industrial Chemistry
Langues : Anglais (eng)
in Industrial & engineering chemistry research > Vol. 49 N° 6 (Mars 2010) . - pp. 2759–2767
Mots-clés : Facile Sodium Alginate Assembly Layered Double Hydroxide Nanostructures Résumé : Self-assembled three-dimensional Ni−Al layered double hydroxide (LDH) nanostructures have been successfully synthesized using a facile biopolymer-assisted approach in the presence of a simple, safe, and inexpensive sodium alginate biopolymer under hydrothermal conditions. The structure and morphology of LDH nanostructures obtained have been investigated by scanning electron microscopy (SEM), powder X-ray diffraction (XRD), high-resolution transmission electron microscopy (HRTEM), Fourier transform infrared spectroscopy (FT-IR), thermogravimetric and differential thermal analysis (TG-DTA), and UV−visible diffuse spectroscopy (UV−vis). Three types of pompon-like, marigold-like, and coral-like LDH nanostructures could be obtained by adjusting the synthesis parameters including hydrothermal aging time, concentration of metal ions, and reaction temperature. A possible formation mechanism for the controlled organization of primary LDH nanosheet building units into special three-dimensional nanostructures is proposed on the basis of the interaction between sodium alginate molecules and LDH crystals. Furthermore, after calcination of LDHs at 500 and 700 °C, the resulting NiO-based mixed metal oxides still maintain the three-dimensional morphology of their LDH precursors to some extent, indicative of the high thermal stability of nanostructures. The findings in this work provide a feasible approach for the morphosynthesis of LDH nanomaterials with special superstructures. Note de contenu : Bibiogr. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie901519h Exemplaires
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Titre : Effect of zirconium doping on hydrogen permeation through strontium cerate membranes Type de document : texte imprimé Auteurs : Jay Kniep, Auteur ; Y. S. Lin, Auteur Année de publication : 2010 Article en page(s) : pp. 2768–2774 Note générale : Industrial Chemistry Langues : Anglais (eng) Mots-clés : Zirconium Doping Hydrogen Permeation Strontium Cerate Membranes Résumé : SrCe0.95Tm0.05O3−δ perovskite-type ceramic membranes offer high hydrogen selectivity, thermal stability, mixed protonic−electronic conductivity, and mechanical strength at temperatures above 600 °C. However, in order for the SrCeO3-based membranes to be used in industrial applications, the chemical stability of the membranes in various environments must be improved. The effect of doping zirconium on the chemical stability, lattice structure, protonic and electronic conductivity, and hydrogen permeation properties of SrCe0.95−xZrxTm0.05O3−δ (0 ≤ x ≤ 0.40) was studied. X-ray diffraction analysis verifies that all samples consist of a single perovskite phase. Doping zirconium in SrCe0.95Tm0.05O3−δ results in a decrease in both the protonic and electronic conductivity of the materials under reducing conditions, and a more significant decrease in hydrogen permeability of the membrane in CO2 free gas streams. In a CO2-containing environment SrCe0.75Zr0.20Tm0.05O3−δ membranes have a larger steady-state H2 flux and superior chemical stability over SrCe0.95Tm0.05O3−δ membranes. Note de contenu : Bibiogr. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie9015182
in Industrial & engineering chemistry research > Vol. 49 N° 6 (Mars 2010) . - pp. 2768–2774[article] Effect of zirconium doping on hydrogen permeation through strontium cerate membranes [texte imprimé] / Jay Kniep, Auteur ; Y. S. Lin, Auteur . - 2010 . - pp. 2768–2774.
Industrial Chemistry
Langues : Anglais (eng)
in Industrial & engineering chemistry research > Vol. 49 N° 6 (Mars 2010) . - pp. 2768–2774
Mots-clés : Zirconium Doping Hydrogen Permeation Strontium Cerate Membranes Résumé : SrCe0.95Tm0.05O3−δ perovskite-type ceramic membranes offer high hydrogen selectivity, thermal stability, mixed protonic−electronic conductivity, and mechanical strength at temperatures above 600 °C. However, in order for the SrCeO3-based membranes to be used in industrial applications, the chemical stability of the membranes in various environments must be improved. The effect of doping zirconium on the chemical stability, lattice structure, protonic and electronic conductivity, and hydrogen permeation properties of SrCe0.95−xZrxTm0.05O3−δ (0 ≤ x ≤ 0.40) was studied. X-ray diffraction analysis verifies that all samples consist of a single perovskite phase. Doping zirconium in SrCe0.95Tm0.05O3−δ results in a decrease in both the protonic and electronic conductivity of the materials under reducing conditions, and a more significant decrease in hydrogen permeability of the membrane in CO2 free gas streams. In a CO2-containing environment SrCe0.75Zr0.20Tm0.05O3−δ membranes have a larger steady-state H2 flux and superior chemical stability over SrCe0.95Tm0.05O3−δ membranes. Note de contenu : Bibiogr. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie9015182 Exemplaires
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Titre : Physicomechanical and thermal properties of jute-nanofiber-reinforced biocopolyester composites Type de document : texte imprimé Auteurs : Kunal Das, Auteur ; Dipa Ray, Auteur ; Chitrita Banerjee, Auteur Année de publication : 2010 Article en page(s) : pp. 2775–2782 Note générale : Industrial Chemistry Langues : Anglais (eng) Mots-clés : Physicomechanical Thermal Properties Jute Nanofiber Biocopolyester Composites Résumé : Jute nanofibers (JNFs) were prepared by treating jute fibers with alkali and dimethyl sulfoxide (DMSO) and then applying acid hydrolysis and were characterized by transmission electron microscopy, scanning electron microscopy, atomic force microscopy, and X-ray diffraction. The JNFs exhibited both spherical an elliptical shapes, with diameter in the range of 50−120 nm. Biocopolyester matrix was reinforced with JNFs at three different loadings (5, 10, and 15 wt %), and the JNF-loaded biocomposites were characterized by X-ray diffraction, tensile testing, differential scanning calorimetry, and moisture uptake. The enhancement in properties was highest for 10 wt % JNF-loaded composites, indicating the most uniform dispersion in this material. Note de contenu : Bibiogr. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie9019984
in Industrial & engineering chemistry research > Vol. 49 N° 6 (Mars 2010) . - pp. 2775–2782[article] Physicomechanical and thermal properties of jute-nanofiber-reinforced biocopolyester composites [texte imprimé] / Kunal Das, Auteur ; Dipa Ray, Auteur ; Chitrita Banerjee, Auteur . - 2010 . - pp. 2775–2782.
Industrial Chemistry
Langues : Anglais (eng)
in Industrial & engineering chemistry research > Vol. 49 N° 6 (Mars 2010) . - pp. 2775–2782
Mots-clés : Physicomechanical Thermal Properties Jute Nanofiber Biocopolyester Composites Résumé : Jute nanofibers (JNFs) were prepared by treating jute fibers with alkali and dimethyl sulfoxide (DMSO) and then applying acid hydrolysis and were characterized by transmission electron microscopy, scanning electron microscopy, atomic force microscopy, and X-ray diffraction. The JNFs exhibited both spherical an elliptical shapes, with diameter in the range of 50−120 nm. Biocopolyester matrix was reinforced with JNFs at three different loadings (5, 10, and 15 wt %), and the JNF-loaded biocomposites were characterized by X-ray diffraction, tensile testing, differential scanning calorimetry, and moisture uptake. The enhancement in properties was highest for 10 wt % JNF-loaded composites, indicating the most uniform dispersion in this material. Note de contenu : Bibiogr. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie9019984 Exemplaires
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Titre : Effect of zirconium doping on hydrogen permeation through strontium cerate membranes Type de document : texte imprimé Auteurs : Jay Kniep, Auteur ; Y. S. Lin, Auteur Année de publication : 2010 Article en page(s) : pp. 2768–2774 Note générale : Industrial Chemistry Langues : Anglais (eng) Mots-clés : Zirconium Doping Hydrogen Permeation Strontium Cerate Membranes Résumé : SrCe0.95Tm0.05O3−δ perovskite-type ceramic membranes offer high hydrogen selectivity, thermal stability, mixed protonic−electronic conductivity, and mechanical strength at temperatures above 600 °C. However, in order for the SrCeO3-based membranes to be used in industrial applications, the chemical stability of the membranes in various environments must be improved. The effect of doping zirconium on the chemical stability, lattice structure, protonic and electronic conductivity, and hydrogen permeation properties of SrCe0.95−xZrxTm0.05O3−δ (0 ≤ x ≤ 0.40) was studied. X-ray diffraction analysis verifies that all samples consist of a single perovskite phase. Doping zirconium in SrCe0.95Tm0.05O3−δ results in a decrease in both the protonic and electronic conductivity of the materials under reducing conditions, and a more significant decrease in hydrogen permeability of the membrane in CO2 free gas streams. In a CO2-containing environment SrCe0.75Zr0.20Tm0.05O3−δ membranes have a larger steady-state H2 flux and superior chemical stability over SrCe0.95Tm0.05O3−δ membranes. Note de contenu : Bibiogr. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie9015182
in Industrial & engineering chemistry research > Vol. 49 N° 6 (Mars 2010) . - pp. 2768–2774[article] Effect of zirconium doping on hydrogen permeation through strontium cerate membranes [texte imprimé] / Jay Kniep, Auteur ; Y. S. Lin, Auteur . - 2010 . - pp. 2768–2774.
Industrial Chemistry
Langues : Anglais (eng)
in Industrial & engineering chemistry research > Vol. 49 N° 6 (Mars 2010) . - pp. 2768–2774
Mots-clés : Zirconium Doping Hydrogen Permeation Strontium Cerate Membranes Résumé : SrCe0.95Tm0.05O3−δ perovskite-type ceramic membranes offer high hydrogen selectivity, thermal stability, mixed protonic−electronic conductivity, and mechanical strength at temperatures above 600 °C. However, in order for the SrCeO3-based membranes to be used in industrial applications, the chemical stability of the membranes in various environments must be improved. The effect of doping zirconium on the chemical stability, lattice structure, protonic and electronic conductivity, and hydrogen permeation properties of SrCe0.95−xZrxTm0.05O3−δ (0 ≤ x ≤ 0.40) was studied. X-ray diffraction analysis verifies that all samples consist of a single perovskite phase. Doping zirconium in SrCe0.95Tm0.05O3−δ results in a decrease in both the protonic and electronic conductivity of the materials under reducing conditions, and a more significant decrease in hydrogen permeability of the membrane in CO2 free gas streams. In a CO2-containing environment SrCe0.75Zr0.20Tm0.05O3−δ membranes have a larger steady-state H2 flux and superior chemical stability over SrCe0.95Tm0.05O3−δ membranes. Note de contenu : Bibiogr. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie9015182 Exemplaires
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Titre : Physicomechanical and thermal properties of jute-nanofiber-reinforced biocopolyester composites Type de document : texte imprimé Auteurs : Kunal Das, Auteur ; Dipa Ray, Auteur ; Chitrita Banerjee, Auteur Année de publication : 2010 Article en page(s) : pp. 2775–2782 Note générale : Industrial Chemistry Langues : Anglais (eng) Mots-clés : Physicomechanical Thermal Jute Nanofiber Reinforced Biocopolyester Composites Résumé : Jute nanofibers (JNFs) were prepared by treating jute fibers with alkali and dimethyl sulfoxide (DMSO) and then applying acid hydrolysis and were characterized by transmission electron microscopy, scanning electron microscopy, atomic force microscopy, and X-ray diffraction. The JNFs exhibited both spherical an elliptical shapes, with diameter in the range of 50−120 nm. Biocopolyester matrix was reinforced with JNFs at three different loadings (5, 10, and 15 wt %), and the JNF-loaded biocomposites were characterized by X-ray diffraction, tensile testing, differential scanning calorimetry, and moisture uptake. The enhancement in properties was highest for 10 wt % JNF-loaded composites, indicating the most uniform dispersion in this material. Note de contenu : Bibiogr. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie9019984
in Industrial & engineering chemistry research > Vol. 49 N° 6 (Mars 2010) . - pp. 2775–2782[article] Physicomechanical and thermal properties of jute-nanofiber-reinforced biocopolyester composites [texte imprimé] / Kunal Das, Auteur ; Dipa Ray, Auteur ; Chitrita Banerjee, Auteur . - 2010 . - pp. 2775–2782.
Industrial Chemistry
Langues : Anglais (eng)
in Industrial & engineering chemistry research > Vol. 49 N° 6 (Mars 2010) . - pp. 2775–2782
Mots-clés : Physicomechanical Thermal Jute Nanofiber Reinforced Biocopolyester Composites Résumé : Jute nanofibers (JNFs) were prepared by treating jute fibers with alkali and dimethyl sulfoxide (DMSO) and then applying acid hydrolysis and were characterized by transmission electron microscopy, scanning electron microscopy, atomic force microscopy, and X-ray diffraction. The JNFs exhibited both spherical an elliptical shapes, with diameter in the range of 50−120 nm. Biocopolyester matrix was reinforced with JNFs at three different loadings (5, 10, and 15 wt %), and the JNF-loaded biocomposites were characterized by X-ray diffraction, tensile testing, differential scanning calorimetry, and moisture uptake. The enhancement in properties was highest for 10 wt % JNF-loaded composites, indicating the most uniform dispersion in this material. Note de contenu : Bibiogr. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie9019984 Exemplaires
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Titre : Supercritical phase Inversion to form drug-loaded poly(vinylidene fluoride-co-hexafluoropropylene) membranes Type de document : texte imprimé Auteurs : Stefano Cardea, Auteur ; Margherita Sessa, Auteur ; Ernesto Reverchon, Auteur Année de publication : 2010 Article en page(s) : pp. 2783–2789 Note générale : Inustrial Chemistry Langues : Anglais (eng) Mots-clés : Drug Poly vinylidene fluoride co-hexafluoropropylene Membranes Résumé : Membranes loaded with an active principle are one of the alternatives proposed to obtain controlled release pharmaceutical formulations. Until now, several methods have been proposed for the fabrication of membranes as drug delivery devices, such as phase inversion, gas foaming/particulate leaching, and solvent evaporation. Supercritical CO2 (SC-CO2) phase inversion offers an alternative process to obtain solvent-free membranes with short processing times, avoiding the collapse of the structure. We prepared poly(vinylidene fluoride-co-hexafluoropropylene) (PVDF−HFP) loaded membranes by SC-CO2 phase inversion, performing experiments at pressures ranging between 150 and 250 bar and at temperatures ranging between 35 and 55 °C. We selected as the base case the PVDF−HFP−acetone solution at 15% w/w polymer and modified the drug (amoxicillin) concentration from 20 to 50% w/w with respect to PVDF−HFP. Different membranes morphologies, ranging from nanometric gel-like networks (mean pores diameter of about 150 nm) to micrometric cellular structures (mean cells diameter ranging between 5 and 12 μm), and different drug distributions were obtained, depending on the process conditions. Drug-controlled release experiments were also performed to study the kinetics and duration of the release process. Note de contenu : Bibiogr. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie901616n
in Industrial & engineering chemistry research > Vol. 49 N° 6 (Mars 2010) . - pp. 2783–2789[article] Supercritical phase Inversion to form drug-loaded poly(vinylidene fluoride-co-hexafluoropropylene) membranes [texte imprimé] / Stefano Cardea, Auteur ; Margherita Sessa, Auteur ; Ernesto Reverchon, Auteur . - 2010 . - pp. 2783–2789.
Inustrial Chemistry
Langues : Anglais (eng)
in Industrial & engineering chemistry research > Vol. 49 N° 6 (Mars 2010) . - pp. 2783–2789
Mots-clés : Drug Poly vinylidene fluoride co-hexafluoropropylene Membranes Résumé : Membranes loaded with an active principle are one of the alternatives proposed to obtain controlled release pharmaceutical formulations. Until now, several methods have been proposed for the fabrication of membranes as drug delivery devices, such as phase inversion, gas foaming/particulate leaching, and solvent evaporation. Supercritical CO2 (SC-CO2) phase inversion offers an alternative process to obtain solvent-free membranes with short processing times, avoiding the collapse of the structure. We prepared poly(vinylidene fluoride-co-hexafluoropropylene) (PVDF−HFP) loaded membranes by SC-CO2 phase inversion, performing experiments at pressures ranging between 150 and 250 bar and at temperatures ranging between 35 and 55 °C. We selected as the base case the PVDF−HFP−acetone solution at 15% w/w polymer and modified the drug (amoxicillin) concentration from 20 to 50% w/w with respect to PVDF−HFP. Different membranes morphologies, ranging from nanometric gel-like networks (mean pores diameter of about 150 nm) to micrometric cellular structures (mean cells diameter ranging between 5 and 12 μm), and different drug distributions were obtained, depending on the process conditions. Drug-controlled release experiments were also performed to study the kinetics and duration of the release process. Note de contenu : Bibiogr. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie901616n Exemplaires
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Titre : Systematic multimodeling methodology applied to an activated sludge reactor model Type de document : texte imprimé Auteurs : Anca Maria Nagy, Auteur ; Gilles Mourot, Auteur ; Benoît Marx, Auteur Année de publication : 2010 Article en page(s) : pp. 2790–2799 Note générale : Industrial Chemistry Langues : Anglais (eng) Mots-clés : Activated Sludge Reactor Multimodeling Résumé : In this article, an analytical method is used to obtain multiple model (MM) forms strictly equivalent to a given nonlinear model. The proposed method induces no information loss, contrary to existing order reduction methods. Several MMs formally equivalent to the initial model may be obtained, due to the intermediate quasi-LPV forms. Thus some criteria are given, using the linear matrix inequality (LMI) formulation, in order to chose the most suitable MM for analysis or control purpose. This method is applied to an activated sludge reactor model. Note de contenu : Bibiogr. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie8017687
in Industrial & engineering chemistry research > Vol. 49 N° 6 (Mars 2010) . - pp. 2790–2799[article] Systematic multimodeling methodology applied to an activated sludge reactor model [texte imprimé] / Anca Maria Nagy, Auteur ; Gilles Mourot, Auteur ; Benoît Marx, Auteur . - 2010 . - pp. 2790–2799.
Industrial Chemistry
Langues : Anglais (eng)
in Industrial & engineering chemistry research > Vol. 49 N° 6 (Mars 2010) . - pp. 2790–2799
Mots-clés : Activated Sludge Reactor Multimodeling Résumé : In this article, an analytical method is used to obtain multiple model (MM) forms strictly equivalent to a given nonlinear model. The proposed method induces no information loss, contrary to existing order reduction methods. Several MMs formally equivalent to the initial model may be obtained, due to the intermediate quasi-LPV forms. Thus some criteria are given, using the linear matrix inequality (LMI) formulation, in order to chose the most suitable MM for analysis or control purpose. This method is applied to an activated sludge reactor model. Note de contenu : Bibiogr. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie8017687 Exemplaires
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Titre : Online monitoring of batch processes using IOHMM based MPLS Type de document : texte imprimé Auteurs : Junghui Chen, Auteur ; Che-Ming Song, Auteur ; Tong-Yang Hsu, Auteur Année de publication : 2010 Article en page(s) : pp.2800–2811 Note générale : Industrial Chemistry Langues : Anglais (eng) Mots-clés : Online IOHMM MPLS collinearity dynamic information Résumé : Online monitoring of the batch process is extremely important to the health assessment of the batch operation; it ensures making products of consistent high quality. In this paper, an integrated framework called IOHMM-MPLS is proposed to monitor the performance of a batch process. It consists of the input−output hidden Markov model (IOHMM) and multiway partial least-squares (MPLS) method. The sequence of the process variables and the product quality variables are decomposed into linear outer relations, which can be handled by MPLS, and simple inner dynamic sequence relations, which can be coped with by a set of single-input−single-output IOHMM models. MPLS is used to solve the problem of high dimensionality and collinearity, while IOHMM is used to capture the transition probability of the dynamic information. The combined IOHMM-MPLS method requires a smaller computational load, converges faster, and encounters lesser occurrences of false detection. It utilizes output quality variables and within batch process variables to find the most likely state evolution. After extracting the essential features of the past operating information, subsequently, two simple monitoring charts are presented to track the progress of each batch run and monitor the occurrence of the observable upsets. The proposed model is successfully applied to two simulated problems. Note de contenu : Bibiogr. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie900536z
in Industrial & engineering chemistry research > Vol. 49 N° 6 (Mars 2010) . - pp.2800–2811[article] Online monitoring of batch processes using IOHMM based MPLS [texte imprimé] / Junghui Chen, Auteur ; Che-Ming Song, Auteur ; Tong-Yang Hsu, Auteur . - 2010 . - pp.2800–2811.
Industrial Chemistry
Langues : Anglais (eng)
in Industrial & engineering chemistry research > Vol. 49 N° 6 (Mars 2010) . - pp.2800–2811
Mots-clés : Online IOHMM MPLS collinearity dynamic information Résumé : Online monitoring of the batch process is extremely important to the health assessment of the batch operation; it ensures making products of consistent high quality. In this paper, an integrated framework called IOHMM-MPLS is proposed to monitor the performance of a batch process. It consists of the input−output hidden Markov model (IOHMM) and multiway partial least-squares (MPLS) method. The sequence of the process variables and the product quality variables are decomposed into linear outer relations, which can be handled by MPLS, and simple inner dynamic sequence relations, which can be coped with by a set of single-input−single-output IOHMM models. MPLS is used to solve the problem of high dimensionality and collinearity, while IOHMM is used to capture the transition probability of the dynamic information. The combined IOHMM-MPLS method requires a smaller computational load, converges faster, and encounters lesser occurrences of false detection. It utilizes output quality variables and within batch process variables to find the most likely state evolution. After extracting the essential features of the past operating information, subsequently, two simple monitoring charts are presented to track the progress of each batch run and monitor the occurrence of the observable upsets. The proposed model is successfully applied to two simulated problems. Note de contenu : Bibiogr. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie900536z Exemplaires
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Titre : Strategic capacity allocation under uncertainty by using a two-stage stochastic decomposition algorithm with incumbent solutions Type de document : texte imprimé Auteurs : Sergio Frausto-Hernandez, Auteur ; Vicente Rico-Ramirez, Auteur ; Ignacio E. Grossmann, Auteur Année de publication : 2010 Article en page(s) : pp. 2812–2821 Note générale : Industrial Chemistry Langues : Anglais (eng) Mots-clés : Strategic Capacity under Uncertainty Stochastic Decomposition Algorithm Incumbent Résumé : This paper addresses the optimization of strategic capacity allocation problems under uncertainty. Uncertain parameters include the availabilities and the demands of chemicals. The optimization problem is formulated as a two-stage mixed-integer stochastic program (first-stage integer) that maximizes the expected net present value of the project over the time horizon. The net present value includes the discounted investment costs, operating costs, and revenues from sales in the markets. The decisions about the selection of processes and about the plant capacities are defined as the first stage decision variables; given such first stage decisions, recourse is then provided by calculating the operating costs in the second stage. The paper presents the two-stage model and the solution framework. A stochastic decomposition algorithm (SD) based on incumbent solution is used as the solution algorithm. The use of incumbent solutions as convergence criterion allows us to solve the problem in reasonable computational time. Two capacity allocation problems are used as case studies: the first one is a small size problem and is used to compare the stochastic optimal solution against other solution methods; the second one is a larger problem, with an increased number of variables and stochastic parameters. The results show that the stochastic decomposition algorithm with incumbent solutions is stable and robust and greatly reduces the number of samples required for convergence. Note de contenu : Bibiogr. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie901021b
in Industrial & engineering chemistry research > Vol. 49 N° 6 (Mars 2010) . - pp. 2812–2821[article] Strategic capacity allocation under uncertainty by using a two-stage stochastic decomposition algorithm with incumbent solutions [texte imprimé] / Sergio Frausto-Hernandez, Auteur ; Vicente Rico-Ramirez, Auteur ; Ignacio E. Grossmann, Auteur . - 2010 . - pp. 2812–2821.
Industrial Chemistry
Langues : Anglais (eng)
in Industrial & engineering chemistry research > Vol. 49 N° 6 (Mars 2010) . - pp. 2812–2821
Mots-clés : Strategic Capacity under Uncertainty Stochastic Decomposition Algorithm Incumbent Résumé : This paper addresses the optimization of strategic capacity allocation problems under uncertainty. Uncertain parameters include the availabilities and the demands of chemicals. The optimization problem is formulated as a two-stage mixed-integer stochastic program (first-stage integer) that maximizes the expected net present value of the project over the time horizon. The net present value includes the discounted investment costs, operating costs, and revenues from sales in the markets. The decisions about the selection of processes and about the plant capacities are defined as the first stage decision variables; given such first stage decisions, recourse is then provided by calculating the operating costs in the second stage. The paper presents the two-stage model and the solution framework. A stochastic decomposition algorithm (SD) based on incumbent solution is used as the solution algorithm. The use of incumbent solutions as convergence criterion allows us to solve the problem in reasonable computational time. Two capacity allocation problems are used as case studies: the first one is a small size problem and is used to compare the stochastic optimal solution against other solution methods; the second one is a larger problem, with an increased number of variables and stochastic parameters. The results show that the stochastic decomposition algorithm with incumbent solutions is stable and robust and greatly reduces the number of samples required for convergence. Note de contenu : Bibiogr. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie901021b Exemplaires
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Titre : Simultaneous design and control : a new approach and comparisons with existing methodologies Type de document : texte imprimé Auteurs : Luis A. Ricardez-Sandoval, Auteur ; Hector M. Budman, Auteur ; Peter L. Douglas, Auteur Année de publication : 2010 Article en page(s) : pp. 2822–2833 Note générale : Industrial Chemistry Langues : Anglais (eng) Mots-clés : Simultaneous Design New Approach Comparisons Existing Methodologies Résumé : In this work, a new methodology to conduct simultaneous design and control of large-scale systems is presented. The proposed method uses a structured singular value norm calculation (μ) to estimate the worst-case disturbance profile. This profile is then used to simulate the closed-loop nonlinear dynamic process model for obtaining the worst-case output variability and to test the process feasibility constraints. Thus, the proposed method referred to as the hybrid worst-case approach (HWA) methodology combines the analytical μ calculation of the worst-case disturbance and dynamic simulations using the mechanistic closed-loop process model to calculate variability. To test the proposed HWA method the integration of design and control of the reactor section of the Tennessee Eastman process was analyzed. This case study was also used to compare the proposed HWA method to other previously reported methodologies. Although the results obtained by the present HWA method for the case study are slightly conservative, the computational demand required by the present method is found to be 1 order of magnitude smaller than that required by a dynamic optimization-based methodology. Note de contenu : Bibiogr. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie9010707
in Industrial & engineering chemistry research > Vol. 49 N° 6 (Mars 2010) . - pp. 2822–2833[article] Simultaneous design and control : a new approach and comparisons with existing methodologies [texte imprimé] / Luis A. Ricardez-Sandoval, Auteur ; Hector M. Budman, Auteur ; Peter L. Douglas, Auteur . - 2010 . - pp. 2822–2833.
Industrial Chemistry
Langues : Anglais (eng)
in Industrial & engineering chemistry research > Vol. 49 N° 6 (Mars 2010) . - pp. 2822–2833
Mots-clés : Simultaneous Design New Approach Comparisons Existing Methodologies Résumé : In this work, a new methodology to conduct simultaneous design and control of large-scale systems is presented. The proposed method uses a structured singular value norm calculation (μ) to estimate the worst-case disturbance profile. This profile is then used to simulate the closed-loop nonlinear dynamic process model for obtaining the worst-case output variability and to test the process feasibility constraints. Thus, the proposed method referred to as the hybrid worst-case approach (HWA) methodology combines the analytical μ calculation of the worst-case disturbance and dynamic simulations using the mechanistic closed-loop process model to calculate variability. To test the proposed HWA method the integration of design and control of the reactor section of the Tennessee Eastman process was analyzed. This case study was also used to compare the proposed HWA method to other previously reported methodologies. Although the results obtained by the present HWA method for the case study are slightly conservative, the computational demand required by the present method is found to be 1 order of magnitude smaller than that required by a dynamic optimization-based methodology. Note de contenu : Bibiogr. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie9010707 Exemplaires
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Titre : Continuous-molecular targeting for integrated solvent and process design Type de document : texte imprimé Auteurs : Andre Bardow, Auteur ; Klaas Steur, Auteur ; Joachim Gross, Auteur Année de publication : 2010 Article en page(s) : pp. 2834–2840 Note générale : Idustrial Chemistry Langues : Anglais (eng) Mots-clés : Molecular Solvent topology fluid theory study Résumé : An integrated design of processes and solvents is a prerequisite for achieving truly optimized solvent-based processes. However, solving the full integrated problem in a single optimization is usually not possible even for a predefined process topology due to the required discrete choices between molecular structures. Current approaches therefore mostly decompose the integrated problem into a process design and a molecular-design subproblem. The interaction between these subproblems is usually limited in practice, and a direct link between process performance and molecular characteristics of the solvent is not achieved. In this work, a novel methodology for the integrated process and molecular design problem is suggested where the discrete molecular decisions in the integrated design problem are circumvented by defining a hypothetical molecule. The approach is building upon a molecular-based thermodynamic model, where the parameters representing a molecule are treated as continuous. These parameters are optimized together with other process parameters, leading to an ideal hypothetical target molecule (represented by a set of parameters) and a corresponding optimized process. Only in a subsequent step, the parameters of the thermodynamic model representing the hypothetical molecule are mapped onto an existing optimal solvent. The method is illustrated for the design of solvents for carbon dioxide capture where the benefits of the integrated design approach are demonstrated. The perturbed-chain-polar-statistical-associating-fluid theory (PCP-SAFT) equation of state is used as a thermodynamic model. The framework introduced is generic in nature and thus applicable beyond the study of solvents to the integrated design of materials and processes in general. Note de contenu : Bibiogr. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie901281w
in Industrial & engineering chemistry research > Vol. 49 N° 6 (Mars 2010) . - pp. 2834–2840[article] Continuous-molecular targeting for integrated solvent and process design [texte imprimé] / Andre Bardow, Auteur ; Klaas Steur, Auteur ; Joachim Gross, Auteur . - 2010 . - pp. 2834–2840.
Idustrial Chemistry
Langues : Anglais (eng)
in Industrial & engineering chemistry research > Vol. 49 N° 6 (Mars 2010) . - pp. 2834–2840
Mots-clés : Molecular Solvent topology fluid theory study Résumé : An integrated design of processes and solvents is a prerequisite for achieving truly optimized solvent-based processes. However, solving the full integrated problem in a single optimization is usually not possible even for a predefined process topology due to the required discrete choices between molecular structures. Current approaches therefore mostly decompose the integrated problem into a process design and a molecular-design subproblem. The interaction between these subproblems is usually limited in practice, and a direct link between process performance and molecular characteristics of the solvent is not achieved. In this work, a novel methodology for the integrated process and molecular design problem is suggested where the discrete molecular decisions in the integrated design problem are circumvented by defining a hypothetical molecule. The approach is building upon a molecular-based thermodynamic model, where the parameters representing a molecule are treated as continuous. These parameters are optimized together with other process parameters, leading to an ideal hypothetical target molecule (represented by a set of parameters) and a corresponding optimized process. Only in a subsequent step, the parameters of the thermodynamic model representing the hypothetical molecule are mapped onto an existing optimal solvent. The method is illustrated for the design of solvents for carbon dioxide capture where the benefits of the integrated design approach are demonstrated. The perturbed-chain-polar-statistical-associating-fluid theory (PCP-SAFT) equation of state is used as a thermodynamic model. The framework introduced is generic in nature and thus applicable beyond the study of solvents to the integrated design of materials and processes in general. Note de contenu : Bibiogr. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie901281w Exemplaires
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Titre : Multiobjective design of calorific value adjustment process using process simulators Type de document : texte imprimé Auteurs : Hosoo Kim, Auteur ; Ik Hyun Kim, Auteur ; En Sup Yoon, Auteur Année de publication : 2010 Article en page(s) : pp. 2841–2848 Note générale : Industrial Chemistry Langues : Anglais (eng) Mots-clés : Multiobjective Calorific Value Adjustment Simulators Résumé : In this work, we present a solution procedure for design of a chemical process for effectively adjusting calorific values in an offshore regasification terminal. To tackle the technical and commercial issue in the liquefied natural gas (LNG) industry caused by differences of LNG calorific values between importing countries, many methods and configurations are being studied. This design problem is defined in two parts: a generalized disjunctive programming (GDP) problem with one objective and a multiobjective problem for minimizing the operating costs and the performance of natural gas liquids (NGLs). First, the GDP problem has been mathematically reformulated as a mixed-integer nonlinear programming (MINLP) problems, and the MINLP technique incorporated into the process simulator using its own optimization capabilities has been suggested. For solving the resulting bicriterion problem with the MINLP problem, we have suggested the heuristic procedure that reduces the number of discrete solutions which are necessary for complete Pareto optimal sets. The complete Pareto optimal sets for a new calorific value adjustment process under three feedstock scenarios are generated. Note de contenu : Bibiogr. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie901685m
in Industrial & engineering chemistry research > Vol. 49 N° 6 (Mars 2010) . - pp. 2841–2848[article] Multiobjective design of calorific value adjustment process using process simulators [texte imprimé] / Hosoo Kim, Auteur ; Ik Hyun Kim, Auteur ; En Sup Yoon, Auteur . - 2010 . - pp. 2841–2848.
Industrial Chemistry
Langues : Anglais (eng)
in Industrial & engineering chemistry research > Vol. 49 N° 6 (Mars 2010) . - pp. 2841–2848
Mots-clés : Multiobjective Calorific Value Adjustment Simulators Résumé : In this work, we present a solution procedure for design of a chemical process for effectively adjusting calorific values in an offshore regasification terminal. To tackle the technical and commercial issue in the liquefied natural gas (LNG) industry caused by differences of LNG calorific values between importing countries, many methods and configurations are being studied. This design problem is defined in two parts: a generalized disjunctive programming (GDP) problem with one objective and a multiobjective problem for minimizing the operating costs and the performance of natural gas liquids (NGLs). First, the GDP problem has been mathematically reformulated as a mixed-integer nonlinear programming (MINLP) problems, and the MINLP technique incorporated into the process simulator using its own optimization capabilities has been suggested. For solving the resulting bicriterion problem with the MINLP problem, we have suggested the heuristic procedure that reduces the number of discrete solutions which are necessary for complete Pareto optimal sets. The complete Pareto optimal sets for a new calorific value adjustment process under three feedstock scenarios are generated. Note de contenu : Bibiogr. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie901685m Exemplaires
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Titre : Synthesis of heat exchanger networks with optimal placement of multiple utilities Type de document : texte imprimé Auteurs : José María Ponce-Ortega, Auteur ; Medardo Serna-González, Auteur ; Arturo Jimenez-Gutierrez, Auteur Année de publication : 2010 Article en page(s) : pp. 2849–2856 Note générale : Industrial Chemistry Langues : Anglais (eng) Mots-clés : Heat exchanger Networks Synthesis Utilities Résumé : The synthesis problem of optimal heat exchanger networks using multiple utilities is addressed. A mixed integer nonlinear programming (MINLP) model is developed based on a stagewise superstructure that contains all possible matches between hot and cold streams in every stage. Unlike previous MINLP formulations, exchanges of process streams with utilities are allowed in each stage of the superstructure to determine the optimal location of hot and cold utilities. The optimal choice of different types of available utilities is considered through a disjunctive programming formulation. The model can handle forbidden matches and required and restricted matches as well as isothermal and nonisothermal process streams. The MINLP problem is readily solved using commercial local solvers. Four examples are presented to show the application of the proposed methodology. No computation complications were observed in the examples presented, and they required small CPU times. Note de contenu : Bibogr. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie901750a
in Industrial & engineering chemistry research > Vol. 49 N° 6 (Mars 2010) . - pp. 2849–2856[article] Synthesis of heat exchanger networks with optimal placement of multiple utilities [texte imprimé] / José María Ponce-Ortega, Auteur ; Medardo Serna-González, Auteur ; Arturo Jimenez-Gutierrez, Auteur . - 2010 . - pp. 2849–2856.
Industrial Chemistry
Langues : Anglais (eng)
in Industrial & engineering chemistry research > Vol. 49 N° 6 (Mars 2010) . - pp. 2849–2856
Mots-clés : Heat exchanger Networks Synthesis Utilities Résumé : The synthesis problem of optimal heat exchanger networks using multiple utilities is addressed. A mixed integer nonlinear programming (MINLP) model is developed based on a stagewise superstructure that contains all possible matches between hot and cold streams in every stage. Unlike previous MINLP formulations, exchanges of process streams with utilities are allowed in each stage of the superstructure to determine the optimal location of hot and cold utilities. The optimal choice of different types of available utilities is considered through a disjunctive programming formulation. The model can handle forbidden matches and required and restricted matches as well as isothermal and nonisothermal process streams. The MINLP problem is readily solved using commercial local solvers. Four examples are presented to show the application of the proposed methodology. No computation complications were observed in the examples presented, and they required small CPU times. Note de contenu : Bibogr. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie901750a Exemplaires
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Titre : Comparative mass transfer performance studies of CO2 absorption into aqueous solutions of DEAB and MEA Type de document : texte imprimé Auteurs : Kreangkrai Maneeintr, Auteur ; Raphael O. Idem, Auteur ; Paitoon Tontiwachwuthikul, Auteur Année de publication : 2010 Article en page(s) : pp. 2857–2863 Note générale : Industrial Chemistry Langues : Anglais (eng) Mots-clés : Comparative Performance Absorption Aqueous Solutions CO2 DEAB MEA Résumé : The mass transfer performance of the absorption of CO2 in an aqueous solution of a new amino alcohol, 4-diethylamino-2-butanol (DEAB), which has been developed as an effective postcombustion CO2 capture solvent, was investigated and compared with the performance of CO2 absorption in a conventional amine, MEA. The absorption experiments were conducted in an absorption column containing structured packing, whereas the absorption performance was evaluated in terms of the overall mass transfer coefficient, KGav. In particular, the effects of parameters such as inert gas flow rate, liquid flow rate, and solution concentration were compared for both DEAB and MEA. The results show that KGav increases as both the liquid flow rate and concentration of solution increase whereas inert gas flow rate has little or no effect on KGav. An empirical correlation for the mass transfer coefficient for the CO2-DEAB system has been developed as a function of the process parameters. In terms of comparison, the results show that the mass transfer performance of MEA was greater than that of DEAB. However, with the extremely high solubility and ease of regeneration of DEAB based on our previous study, it may be extremely beneficial to formulate an absorption solvent involving both MEA and DEAB in order to take advantage of the synergy effects of high solubility, ease of regeneration as well as the high mass transfer performance of the mixture. Note de contenu : Bibiogr. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie900540v
in Industrial & engineering chemistry research > Vol. 49 N° 6 (Mars 2010) . - pp. 2857–2863[article] Comparative mass transfer performance studies of CO2 absorption into aqueous solutions of DEAB and MEA [texte imprimé] / Kreangkrai Maneeintr, Auteur ; Raphael O. Idem, Auteur ; Paitoon Tontiwachwuthikul, Auteur . - 2010 . - pp. 2857–2863.
Industrial Chemistry
Langues : Anglais (eng)
in Industrial & engineering chemistry research > Vol. 49 N° 6 (Mars 2010) . - pp. 2857–2863
Mots-clés : Comparative Performance Absorption Aqueous Solutions CO2 DEAB MEA Résumé : The mass transfer performance of the absorption of CO2 in an aqueous solution of a new amino alcohol, 4-diethylamino-2-butanol (DEAB), which has been developed as an effective postcombustion CO2 capture solvent, was investigated and compared with the performance of CO2 absorption in a conventional amine, MEA. The absorption experiments were conducted in an absorption column containing structured packing, whereas the absorption performance was evaluated in terms of the overall mass transfer coefficient, KGav. In particular, the effects of parameters such as inert gas flow rate, liquid flow rate, and solution concentration were compared for both DEAB and MEA. The results show that KGav increases as both the liquid flow rate and concentration of solution increase whereas inert gas flow rate has little or no effect on KGav. An empirical correlation for the mass transfer coefficient for the CO2-DEAB system has been developed as a function of the process parameters. In terms of comparison, the results show that the mass transfer performance of MEA was greater than that of DEAB. However, with the extremely high solubility and ease of regeneration of DEAB based on our previous study, it may be extremely beneficial to formulate an absorption solvent involving both MEA and DEAB in order to take advantage of the synergy effects of high solubility, ease of regeneration as well as the high mass transfer performance of the mixture. Note de contenu : Bibiogr. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie900540v Exemplaires
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Titre : Quantitative simulation of the granulation process of activated sludge for wastewater treatment Type de document : texte imprimé Auteurs : Bing-Jie Ni, Auteur ; Guo-Ping Sheng, Auteur ; Xiao-Yan Li, Auteur Année de publication : 2010 Article en page(s) : pp. 2864–2873 Note générale : Industrial Chemistry Langues : Anglais (eng) Mots-clés : Quantitative--Simulation--Granulation--Activated Sludge-- Wastewater--Treatment Résumé : The granulation process of activated sludge, taking the sludge in two sequencing batch reactors (SBRs) respectively fed with soybean-processing and fatty-acids-rich wastewaters as an example, is quantitatively simulated in this work. On the basis of a mixed-culture biofilm model and a simultaneous storage and growth model, a new model incorporating microbial growth, oxygen transfer, substrate diffusion, increased granule size, and biomass detachment is formulated to describe the granulation process of activated sludge. Parameter estimation results of no evident cross-correlation and low 95% confidence intervals indicate a good identification of the obtained parameter values. The model evaluation results of three different case studies demonstrate that the developed model is applicable to describing the aerobic sludge granulation process appropriately. With this model, the aerobic granulation process in terms of mean radius profiles could be quantitatively characterized. Note de contenu : Bbibiogr. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie901252k
in Industrial & engineering chemistry research > Vol. 49 N° 6 (Mars 2010) . - pp. 2864–2873[article] Quantitative simulation of the granulation process of activated sludge for wastewater treatment [texte imprimé] / Bing-Jie Ni, Auteur ; Guo-Ping Sheng, Auteur ; Xiao-Yan Li, Auteur . - 2010 . - pp. 2864–2873.
Industrial Chemistry
Langues : Anglais (eng)
in Industrial & engineering chemistry research > Vol. 49 N° 6 (Mars 2010) . - pp. 2864–2873
Mots-clés : Quantitative--Simulation--Granulation--Activated Sludge-- Wastewater--Treatment Résumé : The granulation process of activated sludge, taking the sludge in two sequencing batch reactors (SBRs) respectively fed with soybean-processing and fatty-acids-rich wastewaters as an example, is quantitatively simulated in this work. On the basis of a mixed-culture biofilm model and a simultaneous storage and growth model, a new model incorporating microbial growth, oxygen transfer, substrate diffusion, increased granule size, and biomass detachment is formulated to describe the granulation process of activated sludge. Parameter estimation results of no evident cross-correlation and low 95% confidence intervals indicate a good identification of the obtained parameter values. The model evaluation results of three different case studies demonstrate that the developed model is applicable to describing the aerobic sludge granulation process appropriately. With this model, the aerobic granulation process in terms of mean radius profiles could be quantitatively characterized. Note de contenu : Bbibiogr. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie901252k Exemplaires
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Titre : Process development, simulation, and industrial implementation of a new coal-gasification wastewater treatment installation for phenol and ammonia removal Type de document : texte imprimé Auteurs : Zhenjiang Yu, Auteur ; Yun Chen, Auteur ; Dachun Feng, Auteur Année de publication : 2010 Article en page(s) : pp. 2874–2881 Note générale : Industrial Chemistry Langues : Anglais (eng) Mots-clés : Simulation-- Industrial--Coal-Gasification--Wastewater--Treatment--Installation--Phenol--Ammonia Résumé : Coal-gasification wastewater poses serious problems in the Lurgi process. It cannot be easily purified, as the high pH value of the wastewater limits the dephenolization efficiency of extraction. This work proposes a new process to remove ammonia and sour gas in order to reduce the pH value of the wastewater from 9 to below 7, and next to remove phenol with solvent extraction under acidic conditions. This new process consists of a wastewater stripper with side-draw to remove ammonia and sour gas, an extractor to remove phenol, and two distillation columns to recover extractant. Process simulation was conducted to study the performance of the new process and to perform a detailed design. The complex multicomponent system NH3−CO2−H2S−NaOH−phenol−H2O was analyzed when simulating the wastewater stripping. The new process has been successfully implemented in an industrial installation for coal-gasification wastewater treatment with a capacity of 2000 tons/day. Satisfactory agreement was obtained between the simulation results and the industrial implementation of the new process. The new process, when compared with the old one, recovers phenols more efficiently and produces a wastewater stream acceptable for later biological treatment. Note de contenu : Bibiogr. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie901958j
in Industrial & engineering chemistry research > Vol. 49 N° 6 (Mars 2010) . - pp. 2874–2881[article] Process development, simulation, and industrial implementation of a new coal-gasification wastewater treatment installation for phenol and ammonia removal [texte imprimé] / Zhenjiang Yu, Auteur ; Yun Chen, Auteur ; Dachun Feng, Auteur . - 2010 . - pp. 2874–2881.
Industrial Chemistry
Langues : Anglais (eng)
in Industrial & engineering chemistry research > Vol. 49 N° 6 (Mars 2010) . - pp. 2874–2881
Mots-clés : Simulation-- Industrial--Coal-Gasification--Wastewater--Treatment--Installation--Phenol--Ammonia Résumé : Coal-gasification wastewater poses serious problems in the Lurgi process. It cannot be easily purified, as the high pH value of the wastewater limits the dephenolization efficiency of extraction. This work proposes a new process to remove ammonia and sour gas in order to reduce the pH value of the wastewater from 9 to below 7, and next to remove phenol with solvent extraction under acidic conditions. This new process consists of a wastewater stripper with side-draw to remove ammonia and sour gas, an extractor to remove phenol, and two distillation columns to recover extractant. Process simulation was conducted to study the performance of the new process and to perform a detailed design. The complex multicomponent system NH3−CO2−H2S−NaOH−phenol−H2O was analyzed when simulating the wastewater stripping. The new process has been successfully implemented in an industrial installation for coal-gasification wastewater treatment with a capacity of 2000 tons/day. Satisfactory agreement was obtained between the simulation results and the industrial implementation of the new process. The new process, when compared with the old one, recovers phenols more efficiently and produces a wastewater stream acceptable for later biological treatment. Note de contenu : Bibiogr. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie901958j Exemplaires
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Titre : Prediction of equillibrium sorption isotherm : comparison of linear and nonlinear methods Type de document : texte imprimé Auteurs : Siddharth Parimal, Auteur ; Murari Prasad, Auteur ; Ujjwal Bhaskar, Auteur Année de publication : 2010 Article en page(s) : pp. 2882–2888 Note générale : Industrial hemistry Langues : Anglais (eng) Mots-clés : Prediction--Equillibrium--Sorption Isotherm--Linear--Nonlinea Résumé : Sorption of three divalent toxic metal ions, viz. copper, lead, and zinc, onto a low-cost aluminosilicate mineral, pyrophyllite, was studied in a single component system at four different temperatures. Four isotherms—Freundlich, Langmuir, Redlich−Peterson, and Temkin—were examined in order to test their suitability for the given sets of experimental data. A comparison of the linear least-squares method and a trial-and-error nonlinear method of the four isotherms was done. The Langmuir isotherm had four different linear forms, and all of them were individually studied and compared with the others. The parameters of all the four forms of the Langmuir isotherm obtained by the linear method were different. Langmuir-I is the most popular form of the Langmuir isotherm having the highest coefficient of determination values (0.996886) compared with other linear forms of the Langmuir isotherm. The Redlich−Peterson isotherm produced a higher coefficient of determination values (0.999234) in comparison to all the isotherms studied. Note de contenu : Bibiogr. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie9013343
in Industrial & engineering chemistry research > Vol. 49 N° 6 (Mars 2010) . - pp. 2882–2888[article] Prediction of equillibrium sorption isotherm : comparison of linear and nonlinear methods [texte imprimé] / Siddharth Parimal, Auteur ; Murari Prasad, Auteur ; Ujjwal Bhaskar, Auteur . - 2010 . - pp. 2882–2888.
Industrial hemistry
Langues : Anglais (eng)
in Industrial & engineering chemistry research > Vol. 49 N° 6 (Mars 2010) . - pp. 2882–2888
Mots-clés : Prediction--Equillibrium--Sorption Isotherm--Linear--Nonlinea Résumé : Sorption of three divalent toxic metal ions, viz. copper, lead, and zinc, onto a low-cost aluminosilicate mineral, pyrophyllite, was studied in a single component system at four different temperatures. Four isotherms—Freundlich, Langmuir, Redlich−Peterson, and Temkin—were examined in order to test their suitability for the given sets of experimental data. A comparison of the linear least-squares method and a trial-and-error nonlinear method of the four isotherms was done. The Langmuir isotherm had four different linear forms, and all of them were individually studied and compared with the others. The parameters of all the four forms of the Langmuir isotherm obtained by the linear method were different. Langmuir-I is the most popular form of the Langmuir isotherm having the highest coefficient of determination values (0.996886) compared with other linear forms of the Langmuir isotherm. The Redlich−Peterson isotherm produced a higher coefficient of determination values (0.999234) in comparison to all the isotherms studied. Note de contenu : Bibiogr. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie9013343 Exemplaires
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Titre : Separation of hg(II) from Its aqueous solution using bulk liquid membrane Type de document : texte imprimé Auteurs : Ameer Basha Shaik, Auteur ; Kabita Chakrabarty, Auteur ; Prabirkumar Saha, Auteur Année de publication : 2010 Article en page(s) : pp. 2889–2894 Note générale : Industrial Chemistry Langues : Anglais (eng) Résumé : The focus of this paper is the separation of Hg(II) ions in anionic form from its aqueous solution through bulk liquid membrane (BLM). The efficiency of transport and extraction of Hg (II) through BLM was probed under various experimental criteria such as choice of solvent, operating conditions, and configuration of the system that would render optimal functioning of the BLM. The solvent−carrier combination, dichloroethane−trioctylamine (TOA), shows promising result in the extraction of Hg(II). Investigation was carried out at various process conditions, such as different combinations of pH, initial feed and strip phase concentrations and carrier concentration, and their effects on the equilibrium distribution as well as on the transport of Hg(II) were studied. It was observed that mercury transport phenomenon highly dependent on feed phase pH. Increase of carrier concentration and strip phase concentration increases the transport of mercury up to a certain limit. Initial feed concentration has no significant effect on the extraction of mercury up to 1 mg L−1. Note de contenu : Biboigr. ISSN : 0888-5885
in Industrial & engineering chemistry research > Vol. 49 N° 6 (Mars 2010) . - pp. 2889–2894[article] Separation of hg(II) from Its aqueous solution using bulk liquid membrane [texte imprimé] / Ameer Basha Shaik, Auteur ; Kabita Chakrabarty, Auteur ; Prabirkumar Saha, Auteur . - 2010 . - pp. 2889–2894.
Industrial Chemistry
Langues : Anglais (eng)
in Industrial & engineering chemistry research > Vol. 49 N° 6 (Mars 2010) . - pp. 2889–2894
Résumé : The focus of this paper is the separation of Hg(II) ions in anionic form from its aqueous solution through bulk liquid membrane (BLM). The efficiency of transport and extraction of Hg (II) through BLM was probed under various experimental criteria such as choice of solvent, operating conditions, and configuration of the system that would render optimal functioning of the BLM. The solvent−carrier combination, dichloroethane−trioctylamine (TOA), shows promising result in the extraction of Hg(II). Investigation was carried out at various process conditions, such as different combinations of pH, initial feed and strip phase concentrations and carrier concentration, and their effects on the equilibrium distribution as well as on the transport of Hg(II) were studied. It was observed that mercury transport phenomenon highly dependent on feed phase pH. Increase of carrier concentration and strip phase concentration increases the transport of mercury up to a certain limit. Initial feed concentration has no significant effect on the extraction of mercury up to 1 mg L−1. Note de contenu : Biboigr. ISSN : 0888-5885 Exemplaires
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Titre : Effects of sintering on the properties of La0.6Sr0.4Co0.2Fe0.8O3−δ perovskite hollow fiber membranes Type de document : texte imprimé Auteurs : Xiaoyao Tan, Auteur ; Zhigang Wang, Auteur ; Kang Li, Auteur Année de publication : 2010 Article en page(s) : pp. 2895–2901 Note générale : Industrial Chemistrey Langues : Anglais (eng) Mots-clés : Separation--Hg(II)--Aqueous Solution--Bulk--Liquid--Membrane Résumé : La0.6Sr0.4Co0.2Fe0.8O3−δ (LSCF) hollow fiber membrane precursors were prepared by spinning a starting suspension containing 68.75 wt % LSCF powders, 6.25 wt % polyethersulfone (PESf), and 25.0 wt % N-methyl-2-pyrrolidinone (NMP) at room temperature using deionized water and tape water as the internal and external coagulants, respectively. High temperature sintering was carried out in a range of 1200−1500 °C to study the influences of the sintering process on the properties of the LSCF hollow fiber membranes including the microstructure, crystalline phase, mechanical strength, as well as the oxygen permeability. Mechanical strength of the LSCF hollow fibers increased with increasing sintering temperature and reached a maximum of 115 MPa at 1500 °C sintering temperature. To obtain gastight LSCF hollow fiber membranes, the sintering temperature must be higher than 1250 °C, and the sintering time must be longer than 2 h. However, higher than 1350 °C sintering temperature would facilitate the formation of sulfate impurity phases, resulting in noticeable reduction of oxygen permeation flux. The optimum sintering temperature should be around 1300 °C, and the sintering time should be within the range of 2−4 h to obtain the gastight and high flux LSCF hollow fiber membranes. Note de contenu : Bibiogr. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie901403u
in Industrial & engineering chemistry research > Vol. 49 N° 6 (Mars 2010) . - pp. 2895–2901[article] Effects of sintering on the properties of La0.6Sr0.4Co0.2Fe0.8O3−δ perovskite hollow fiber membranes [texte imprimé] / Xiaoyao Tan, Auteur ; Zhigang Wang, Auteur ; Kang Li, Auteur . - 2010 . - pp. 2895–2901.
Industrial Chemistrey
Langues : Anglais (eng)
in Industrial & engineering chemistry research > Vol. 49 N° 6 (Mars 2010) . - pp. 2895–2901
Mots-clés : Separation--Hg(II)--Aqueous Solution--Bulk--Liquid--Membrane Résumé : La0.6Sr0.4Co0.2Fe0.8O3−δ (LSCF) hollow fiber membrane precursors were prepared by spinning a starting suspension containing 68.75 wt % LSCF powders, 6.25 wt % polyethersulfone (PESf), and 25.0 wt % N-methyl-2-pyrrolidinone (NMP) at room temperature using deionized water and tape water as the internal and external coagulants, respectively. High temperature sintering was carried out in a range of 1200−1500 °C to study the influences of the sintering process on the properties of the LSCF hollow fiber membranes including the microstructure, crystalline phase, mechanical strength, as well as the oxygen permeability. Mechanical strength of the LSCF hollow fibers increased with increasing sintering temperature and reached a maximum of 115 MPa at 1500 °C sintering temperature. To obtain gastight LSCF hollow fiber membranes, the sintering temperature must be higher than 1250 °C, and the sintering time must be longer than 2 h. However, higher than 1350 °C sintering temperature would facilitate the formation of sulfate impurity phases, resulting in noticeable reduction of oxygen permeation flux. The optimum sintering temperature should be around 1300 °C, and the sintering time should be within the range of 2−4 h to obtain the gastight and high flux LSCF hollow fiber membranes. Note de contenu : Bibiogr. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie901403u Exemplaires
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Titre : Comparative study of separation performance of COFs and MOFs for CH4/CO2/H2 mixtures Type de document : texte imprimé Auteurs : Yunhua Liu, Auteur ; Dahuan Liu, Auteur ; Qingyuan Yang, Auteur Année de publication : 2010 Article en page(s) : pp. 2902–2906 Note générale : Industrial Chemistry Langues : Anglais (eng) Mots-clés : COFs--MOFs--CH4/CO2/H2--Comparative-- Mixtures Résumé : In this work, grand canonical Monte Carlo (GCMC) simulations were performed to evaluate the separation performance of covalent organic frameworks (COFs) compared with that of metal−organic frameworks (MOFs) for CH4/CO2/H2 mixtures. The simulation results show that the adsorption selectivities of COFs and MOFs are similar. The electrostatic contribution of framework charges in COFs should be taken into account, although it is smaller than that in MOFs. In addition, the present work shows that the ideal adsorbed solution theory (IAST) is applicable to most COFs. Note de contenu : Bibiogr. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie901488f
in Industrial & engineering chemistry research > Vol. 49 N° 6 (Mars 2010) . - pp. 2902–2906[article] Comparative study of separation performance of COFs and MOFs for CH4/CO2/H2 mixtures [texte imprimé] / Yunhua Liu, Auteur ; Dahuan Liu, Auteur ; Qingyuan Yang, Auteur . - 2010 . - pp. 2902–2906.
Industrial Chemistry
Langues : Anglais (eng)
in Industrial & engineering chemistry research > Vol. 49 N° 6 (Mars 2010) . - pp. 2902–2906
Mots-clés : COFs--MOFs--CH4/CO2/H2--Comparative-- Mixtures Résumé : In this work, grand canonical Monte Carlo (GCMC) simulations were performed to evaluate the separation performance of covalent organic frameworks (COFs) compared with that of metal−organic frameworks (MOFs) for CH4/CO2/H2 mixtures. The simulation results show that the adsorption selectivities of COFs and MOFs are similar. The electrostatic contribution of framework charges in COFs should be taken into account, although it is smaller than that in MOFs. In addition, the present work shows that the ideal adsorbed solution theory (IAST) is applicable to most COFs. Note de contenu : Bibiogr. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie901488f Exemplaires
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Titre : Chromatographic recovery of monosaccharides for the production of bioethanol from wood Type de document : texte imprimé Auteurs : Jari Heinonen, Auteur ; Tuomo Sainio, Auteur Année de publication : 2010 Article en page(s) : pp. 2907–2915 Note générale : Industrial Chemistry Langues : Anglais (eng) Mots-clés : Chromatographic--Recovery--Monosaccharides-- Bioethanol--Wood Résumé : Chromatographic recovery of monosaccharides from concentrated-acid hydrolysates of spruce and birch was investigated for the production of bioethanol from lignocellulose. The effects of resin cross-linkage, column loading, and hydrolysate composition on the yield of monosaccharides and the productivity of the process were of particular interest. Three strong acid cation-exchange resins (gel type) were used. Chromatographic separation experiments were done in a batch column. Monosaccharides were recovered as a “center cut” between sulfuric acid and acetic acid. Hydroxymethyl furfural and furfural, which inhibit the fermentation of monosaccharides, were completely separated from the other components. The highest H2SO4−monosaccharide separation efficiency was obtained with a 6 wt % cross-linked resin. The monosaccharide−acetic acid separation efficiency was found to improve with increasing resin cross-linkage. In the case of high amounts of acetic acid in the hydrolysate, a resin with a high cross-link density is needed for a good yield of monosaccharides. With hydrolysates containing small amounts of acetic acid, a 6 wt % cross-linked resin was found to give the highest yield. The productivity of the process was found to increase with the resin cross-linkage (up to 8 wt %). The optimum column loading depends on whether a high monosaccharide yield or high productivity is desired. The highest yield is obtained with a low loading. As to the productivity, the optimum loading was found to be approximately 10 vol % of the bed volume. Note de contenu : Bibiogr. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie901598z
in Industrial & engineering chemistry research > Vol. 49 N° 6 (Mars 2010) . - pp. 2907–2915[article] Chromatographic recovery of monosaccharides for the production of bioethanol from wood [texte imprimé] / Jari Heinonen, Auteur ; Tuomo Sainio, Auteur . - 2010 . - pp. 2907–2915.
Industrial Chemistry
Langues : Anglais (eng)
in Industrial & engineering chemistry research > Vol. 49 N° 6 (Mars 2010) . - pp. 2907–2915
Mots-clés : Chromatographic--Recovery--Monosaccharides-- Bioethanol--Wood Résumé : Chromatographic recovery of monosaccharides from concentrated-acid hydrolysates of spruce and birch was investigated for the production of bioethanol from lignocellulose. The effects of resin cross-linkage, column loading, and hydrolysate composition on the yield of monosaccharides and the productivity of the process were of particular interest. Three strong acid cation-exchange resins (gel type) were used. Chromatographic separation experiments were done in a batch column. Monosaccharides were recovered as a “center cut” between sulfuric acid and acetic acid. Hydroxymethyl furfural and furfural, which inhibit the fermentation of monosaccharides, were completely separated from the other components. The highest H2SO4−monosaccharide separation efficiency was obtained with a 6 wt % cross-linked resin. The monosaccharide−acetic acid separation efficiency was found to improve with increasing resin cross-linkage. In the case of high amounts of acetic acid in the hydrolysate, a resin with a high cross-link density is needed for a good yield of monosaccharides. With hydrolysates containing small amounts of acetic acid, a 6 wt % cross-linked resin was found to give the highest yield. The productivity of the process was found to increase with the resin cross-linkage (up to 8 wt %). The optimum column loading depends on whether a high monosaccharide yield or high productivity is desired. The highest yield is obtained with a low loading. As to the productivity, the optimum loading was found to be approximately 10 vol % of the bed volume. Note de contenu : Bibiogr. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie901598z Exemplaires
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Titre : Quantum chemical based screening of ionic liquids for the extraction of phenol from aqueous solution Type de document : texte imprimé Auteurs : Sidhartha Mohanty, Auteur ; Tamal Banerjee, Auteur ; Kaustubha Mohanty, Auteur Année de publication : 2010 Article en page(s) : pp. 2916–2925 Note générale : Industrial Chemistry Langues : Anglais (eng) Mots-clés : Screening--Chemical--Quantum--Liquids--Ionic--Phenol--Aqueous Solution Résumé : Room-temperature ionic liquids (ILs), because of their various advantages, are superior extractants than the traditional volatile organic solvents (VOCs) used for liquid−liquid extraction. This work reports the judicious screening of various ILs for the extraction of phenol from aqueous solutions. A quantum chemical based “conductor-like screening model for real solvents” (COSMO-RS) is used for the prediction of selectivity of phenol in aqueous medium at infinite dilution. A combination of 16 cations and 26 anions, which resulted in 416 possible ILs, is used to determine the best extractant for the removal of phenol from aqueous solutions. During the screening process, [TBTDP] and [OMIM] gave the highest selectivity among the phosphonium and imidazolium based cations, respectively. Similarly, the favorable anions are those where no sterical shielding effect around their charge centers exists, such as [CH3SO3], [OAc], [Cl], and [Br]. The best IL screened is [OMIM][Dec], which gave the highest selectivity of 111. Note de contenu : Bibiogr. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie901684q
in Industrial & engineering chemistry research > Vol. 49 N° 6 (Mars 2010) . - pp. 2916–2925[article] Quantum chemical based screening of ionic liquids for the extraction of phenol from aqueous solution [texte imprimé] / Sidhartha Mohanty, Auteur ; Tamal Banerjee, Auteur ; Kaustubha Mohanty, Auteur . - 2010 . - pp. 2916–2925.
Industrial Chemistry
Langues : Anglais (eng)
in Industrial & engineering chemistry research > Vol. 49 N° 6 (Mars 2010) . - pp. 2916–2925
Mots-clés : Screening--Chemical--Quantum--Liquids--Ionic--Phenol--Aqueous Solution Résumé : Room-temperature ionic liquids (ILs), because of their various advantages, are superior extractants than the traditional volatile organic solvents (VOCs) used for liquid−liquid extraction. This work reports the judicious screening of various ILs for the extraction of phenol from aqueous solutions. A quantum chemical based “conductor-like screening model for real solvents” (COSMO-RS) is used for the prediction of selectivity of phenol in aqueous medium at infinite dilution. A combination of 16 cations and 26 anions, which resulted in 416 possible ILs, is used to determine the best extractant for the removal of phenol from aqueous solutions. During the screening process, [TBTDP] and [OMIM] gave the highest selectivity among the phosphonium and imidazolium based cations, respectively. Similarly, the favorable anions are those where no sterical shielding effect around their charge centers exists, such as [CH3SO3], [OAc], [Cl], and [Br]. The best IL screened is [OMIM][Dec], which gave the highest selectivity of 111. Note de contenu : Bibiogr. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie901684q Exemplaires
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Titre : Measurement and analysis of gas bubble evolution from an anode in electrolytic cells Type de document : texte imprimé Auteurs : Supathorn Phongikaroon, Auteur ; Robert O. Hoover, Auteur ; Emily C. Barker, Auteur Année de publication : 2010 Article en page(s) : pp. 2926–2931 Note générale : Industriel Chemistry Langues : Anglais (eng) Mots-clés : Measurement--Analysis--Gas--Bubble--Evolution--Anode--Electrolytic--Cells Résumé : Measurement and analysis of oxygen gas bubbles generated from an anode in different aqueous electrolytic solutions have been studied at different applied currents (I). Bubble size distribution (BSD) was measured by using a high-speed digital camera, while corresponding voltage and current were recorded by an electrophoresis power supply. At low aqueous kinematic viscosity (νc Note de contenu : Bibiogr. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie900908c
in Industrial & engineering chemistry research > Vol. 49 N° 6 (Mars 2010) . - pp. 2926–2931[article] Measurement and analysis of gas bubble evolution from an anode in electrolytic cells [texte imprimé] / Supathorn Phongikaroon, Auteur ; Robert O. Hoover, Auteur ; Emily C. Barker, Auteur . - 2010 . - pp. 2926–2931.
Industriel Chemistry
Langues : Anglais (eng)
in Industrial & engineering chemistry research > Vol. 49 N° 6 (Mars 2010) . - pp. 2926–2931
Mots-clés : Measurement--Analysis--Gas--Bubble--Evolution--Anode--Electrolytic--Cells Résumé : Measurement and analysis of oxygen gas bubbles generated from an anode in different aqueous electrolytic solutions have been studied at different applied currents (I). Bubble size distribution (BSD) was measured by using a high-speed digital camera, while corresponding voltage and current were recorded by an electrophoresis power supply. At low aqueous kinematic viscosity (νc Note de contenu : Bibiogr. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie900908c Exemplaires
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Titre : Statistical robustness study for kinetic models Type de document : texte imprimé Auteurs : Roelof L. J. Coetzer, Auteur ; J. Pirow Engelbrecht, Auteur ; Christo Crause, Auteur Année de publication : 2010 Article en page(s) : pp. 2932–2942 Note générale : Industrial Chemistry Langues : Anglais (eng) Mots-clés : Robustness--Statistica--Kinetic--Models Résumé : Kinetic models are nonlinear systems that depict the dependence between process variables and components or products where the process variables are usually assumed to be fixed. This is under the assumption that the process variables that govern the outputs are fully controllable. However, process variables are not always fully controllable and are more often hard-to-control during normal operation on a full-scale chemical production plant. This Article outlines the methodology of statistical robustness studies for kinetic models. Such an application is apparently new in engineering design and analysis. We illustrate the use of computer experiments and evaluate different response models and designs for determining optimum conditions, which are robust against the variability in the hard-to-control variables. The methodology is demonstrated with two examples, the main one being the ethoxylation of ethylene glycol in an inter cooled pipe reactor. The practical value of statistical robustness studies is that it quantifies the convoluted effect of model uncertainty and model input deviation. Note de contenu : Bibiogr. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie900924g
in Industrial & engineering chemistry research > Vol. 49 N° 6 (Mars 2010) . - pp. 2932–2942[article] Statistical robustness study for kinetic models [texte imprimé] / Roelof L. J. Coetzer, Auteur ; J. Pirow Engelbrecht, Auteur ; Christo Crause, Auteur . - 2010 . - pp. 2932–2942.
Industrial Chemistry
Langues : Anglais (eng)
in Industrial & engineering chemistry research > Vol. 49 N° 6 (Mars 2010) . - pp. 2932–2942
Mots-clés : Robustness--Statistica--Kinetic--Models Résumé : Kinetic models are nonlinear systems that depict the dependence between process variables and components or products where the process variables are usually assumed to be fixed. This is under the assumption that the process variables that govern the outputs are fully controllable. However, process variables are not always fully controllable and are more often hard-to-control during normal operation on a full-scale chemical production plant. This Article outlines the methodology of statistical robustness studies for kinetic models. Such an application is apparently new in engineering design and analysis. We illustrate the use of computer experiments and evaluate different response models and designs for determining optimum conditions, which are robust against the variability in the hard-to-control variables. The methodology is demonstrated with two examples, the main one being the ethoxylation of ethylene glycol in an inter cooled pipe reactor. The practical value of statistical robustness studies is that it quantifies the convoluted effect of model uncertainty and model input deviation. Note de contenu : Bibiogr. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie900924g Exemplaires
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Titre : Phase behavior of linear mixtures in the context of equation of state models Type de document : texte imprimé Auteurs : J. M. Milanesio, Auteur ; M. Cismondi, Auteur ; L. Cardozo-Filho, Auteur Année de publication : 2010 Article en page(s) : pp. 2943–2956 Note générale : Industrial Chemistry Langues : Anglais (eng) Mots-clés : Behavior Linear--Mixtures--Equation--State Models Résumé : Models of the equation of state (EOS) type, based on the van der Waals (vdW) EOS, are able to deal with phase equilibrium properties of asymmetric systems over wide ranges of pressure, composition, and temperature. EOS type models are of great practical interest. In general, EOSs always give a nonideal behavior for mixtures, regardless the form of the set mixing rules. In other words, EOSs have no access to the “ideal solution” state. However, EOS type models do have access to the “linear system” (LS) state. A LS is a mixture whose EOS parameters depend linearly on composition. In a LS, the partial molar parameter of a given component within a multicomponent system equals the pure compound parameter. This could be seen as an alternative form of “ideality”. In this work, we study the phase equilibria of linear systems. We evaluate the phase behavior of binary linear (and also nonlinear) systems by generating different types of charts including pressure−temperature projections of phase equilibrium univariant lines (PTUL), which are defined by vapor−liquid and liquid−liquid (LL) critical lines, by liquid−liquid−vapor (LLV) lines, and by pure compound vapor−liquid saturation lines. The results of this work are useful to improve our understanding of models of the EOS type. Note de contenu : Bibiogr. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie900927f
in Industrial & engineering chemistry research > Vol. 49 N° 6 (Mars 2010) . - pp. 2943–2956[article] Phase behavior of linear mixtures in the context of equation of state models [texte imprimé] / J. M. Milanesio, Auteur ; M. Cismondi, Auteur ; L. Cardozo-Filho, Auteur . - 2010 . - pp. 2943–2956.
Industrial Chemistry
Langues : Anglais (eng)
in Industrial & engineering chemistry research > Vol. 49 N° 6 (Mars 2010) . - pp. 2943–2956
Mots-clés : Behavior Linear--Mixtures--Equation--State Models Résumé : Models of the equation of state (EOS) type, based on the van der Waals (vdW) EOS, are able to deal with phase equilibrium properties of asymmetric systems over wide ranges of pressure, composition, and temperature. EOS type models are of great practical interest. In general, EOSs always give a nonideal behavior for mixtures, regardless the form of the set mixing rules. In other words, EOSs have no access to the “ideal solution” state. However, EOS type models do have access to the “linear system” (LS) state. A LS is a mixture whose EOS parameters depend linearly on composition. In a LS, the partial molar parameter of a given component within a multicomponent system equals the pure compound parameter. This could be seen as an alternative form of “ideality”. In this work, we study the phase equilibria of linear systems. We evaluate the phase behavior of binary linear (and also nonlinear) systems by generating different types of charts including pressure−temperature projections of phase equilibrium univariant lines (PTUL), which are defined by vapor−liquid and liquid−liquid (LL) critical lines, by liquid−liquid−vapor (LLV) lines, and by pure compound vapor−liquid saturation lines. The results of this work are useful to improve our understanding of models of the EOS type. Note de contenu : Bibiogr. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie900927f Exemplaires
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Titre : Artificial vision system for the automatic measurement of interfiber pore characteristics and fiber diameter distribution in nanofiber assemblies Type de document : texte imprimé Auteurs : Emanuele Tomba, Auteur ; Pierantonio Facco, Auteur ; Martina Roso, Auteur Année de publication : 2010 Article en page(s) : pp. 2957–2968 Note générale : Industrial Chemestry Langues : Anglais (eng) Mots-clés : Artificial--Vision--System--Automatic--Measurement--Interfiber--PoreFiber--Diameter--Fiberribution--Nanofiber Résumé : Nanofiber structures are used in several technologies such as membranes, reinforced materials, textiles, catalysts, sensors, and biomedical materials. For all these applications, it is important to know the morphology of the assemblies, in particular their pore and fiber dimension distributions. However, the current methods used to measure pore sizes are all experimental and indirect; furthermore, the fiber diameter distribution is usually determined manually using a digital image of the nanofiber web. In this paper an artificial vision system is proposed to characterize the nanofiber web by automatically measuring several properties related to the interfiber pore distribution and to the nanofiber diameter distribution. The artificial vision system is characterized by a two-section structure: an image processing section and a property measurement section. The image processing section is centered on a multivariate image analysis procedure for the extraction of morphological features from the image. The property measurement section comprises an algorithm for interfiber pore area and pore morphology evaluation and one for fiber diameter distribution measurement that also accounts for the effect of perspective on the lower-level fiber diameters. Because the proposed artificial vision system is completely automatic, measurements can be taken without the need of any experimental setup and with no human intervention. Therefore, besides being fast and accurate, measurements do not suffer from repeatability issues. The ability of the proposed automatic system in characterizing the morphology of a thin nonwoven nanofiber fabric is demonstrated by application to polymer nanofiber membranes obtained by electrospinning. Note de contenu : Bbibiogr. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie901179m
in Industrial & engineering chemistry research > Vol. 49 N° 6 (Mars 2010) . - pp. 2957–2968[article] Artificial vision system for the automatic measurement of interfiber pore characteristics and fiber diameter distribution in nanofiber assemblies [texte imprimé] / Emanuele Tomba, Auteur ; Pierantonio Facco, Auteur ; Martina Roso, Auteur . - 2010 . - pp. 2957–2968.
Industrial Chemestry
Langues : Anglais (eng)
in Industrial & engineering chemistry research > Vol. 49 N° 6 (Mars 2010) . - pp. 2957–2968
Mots-clés : Artificial--Vision--System--Automatic--Measurement--Interfiber--PoreFiber--Diameter--Fiberribution--Nanofiber Résumé : Nanofiber structures are used in several technologies such as membranes, reinforced materials, textiles, catalysts, sensors, and biomedical materials. For all these applications, it is important to know the morphology of the assemblies, in particular their pore and fiber dimension distributions. However, the current methods used to measure pore sizes are all experimental and indirect; furthermore, the fiber diameter distribution is usually determined manually using a digital image of the nanofiber web. In this paper an artificial vision system is proposed to characterize the nanofiber web by automatically measuring several properties related to the interfiber pore distribution and to the nanofiber diameter distribution. The artificial vision system is characterized by a two-section structure: an image processing section and a property measurement section. The image processing section is centered on a multivariate image analysis procedure for the extraction of morphological features from the image. The property measurement section comprises an algorithm for interfiber pore area and pore morphology evaluation and one for fiber diameter distribution measurement that also accounts for the effect of perspective on the lower-level fiber diameters. Because the proposed artificial vision system is completely automatic, measurements can be taken without the need of any experimental setup and with no human intervention. Therefore, besides being fast and accurate, measurements do not suffer from repeatability issues. The ability of the proposed automatic system in characterizing the morphology of a thin nonwoven nanofiber fabric is demonstrated by application to polymer nanofiber membranes obtained by electrospinning. Note de contenu : Bbibiogr. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie901179m Exemplaires
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Titre : Physiologically based pharmacokinetics : a simple, all purpose model Type de document : texte imprimé Auteurs : Michela Di Muria, Auteur ; Gaetano Lamberti, Auteur ; Giuseppe Titomanlio, Auteur Année de publication : 2010 Article en page(s) : pp. 2969–2978 Note générale : Industrial Chemistry Langues : Anglais (eng) Mots-clés : Physiologically--Pharmacokinetics--All Purpose Résumé : To predict the drug hemeatic levels after administration is a goal of great interest in the design of novel pharmaceutical systems and in therapies management. The most reliable approach in pharmacokinetic modeling consists in analyzing the physiology of the living beings and in describing tissues and organs as different biochemical reactors. These models have been identified as physiologically based pharmacokinetic models (PBPK). They can be very detailed in the description, but, in this case, they also claim for the knowledge of an high number of parameters which are difficult to be determined by experiments. In this work, a review of the most complete PBPK models proposed in literature was performed, and a novel PBPK model was developed and validated by comparison with in vivo data available in the literature. The appeals of the novel model are its simplicity and the limited number of parameters required. Last but not least, it was proved able to predict the hemeatic drug levels after different kinds of administrations (intravenous injection, oral assumption of delayed release tablets). Note de contenu : Bibiogr. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie9015717
in Industrial & engineering chemistry research > Vol. 49 N° 6 (Mars 2010) . - pp. 2969–2978[article] Physiologically based pharmacokinetics : a simple, all purpose model [texte imprimé] / Michela Di Muria, Auteur ; Gaetano Lamberti, Auteur ; Giuseppe Titomanlio, Auteur . - 2010 . - pp. 2969–2978.
Industrial Chemistry
Langues : Anglais (eng)
in Industrial & engineering chemistry research > Vol. 49 N° 6 (Mars 2010) . - pp. 2969–2978
Mots-clés : Physiologically--Pharmacokinetics--All Purpose Résumé : To predict the drug hemeatic levels after administration is a goal of great interest in the design of novel pharmaceutical systems and in therapies management. The most reliable approach in pharmacokinetic modeling consists in analyzing the physiology of the living beings and in describing tissues and organs as different biochemical reactors. These models have been identified as physiologically based pharmacokinetic models (PBPK). They can be very detailed in the description, but, in this case, they also claim for the knowledge of an high number of parameters which are difficult to be determined by experiments. In this work, a review of the most complete PBPK models proposed in literature was performed, and a novel PBPK model was developed and validated by comparison with in vivo data available in the literature. The appeals of the novel model are its simplicity and the limited number of parameters required. Last but not least, it was proved able to predict the hemeatic drug levels after different kinds of administrations (intravenous injection, oral assumption of delayed release tablets). Note de contenu : Bibiogr. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie9015717 Exemplaires
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Titre : Mechanistic assessment of microalgal lipid extraction Type de document : texte imprimé Auteurs : Amrita Ranjan, Auteur ; Chetna Patil, Auteur ; Vijayanand S. Moholkar, Auteur Année de publication : 2010 Article en page(s) : pp. 2979–2985 Note générale : Industrial Chemistry Langues : Anglais (eng) Mots-clés : Mechanistic--Microalgal--Lipid--Extraction Résumé : In this paper, we have attempted to make a comparative assessment of the three techniques for extraction of lipids from microalgal biomass, viz. Soxhlet extraction, the Bligh and Dyer method, and sonication. The approach is mechanistic in the sense that we have tried to determine the physical mechanism of extraction of lipids (cell disruption or diffusion across a cell wall) from microalgae using microscopic analysis of extracted biomass. We have also assessed the relative influence of the solvent (or extractant) selectivity and the intensity of convection in the medium on the overall lipid yield. None of the techniques used produced complete disruption of the cells, not even sonication. Thus, the prominent mechanism of lipid extraction was diffusion across a cell wall. Moreover, the selectivity of the solvent was found to be the most dominating factor in overall lipid extraction by diffusion than the intensity of bulk convection in the medium. Note de contenu : Bibiogr. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie9016557
in Industrial & engineering chemistry research > Vol. 49 N° 6 (Mars 2010) . - pp. 2979–2985[article] Mechanistic assessment of microalgal lipid extraction [texte imprimé] / Amrita Ranjan, Auteur ; Chetna Patil, Auteur ; Vijayanand S. Moholkar, Auteur . - 2010 . - pp. 2979–2985.
Industrial Chemistry
Langues : Anglais (eng)
in Industrial & engineering chemistry research > Vol. 49 N° 6 (Mars 2010) . - pp. 2979–2985
Mots-clés : Mechanistic--Microalgal--Lipid--Extraction Résumé : In this paper, we have attempted to make a comparative assessment of the three techniques for extraction of lipids from microalgal biomass, viz. Soxhlet extraction, the Bligh and Dyer method, and sonication. The approach is mechanistic in the sense that we have tried to determine the physical mechanism of extraction of lipids (cell disruption or diffusion across a cell wall) from microalgae using microscopic analysis of extracted biomass. We have also assessed the relative influence of the solvent (or extractant) selectivity and the intensity of convection in the medium on the overall lipid yield. None of the techniques used produced complete disruption of the cells, not even sonication. Thus, the prominent mechanism of lipid extraction was diffusion across a cell wall. Moreover, the selectivity of the solvent was found to be the most dominating factor in overall lipid extraction by diffusion than the intensity of bulk convection in the medium. Note de contenu : Bibiogr. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie9016557 Exemplaires
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Titre : Study of the CO2/sorbent interaction in sorbents prepared with mesoporous supports and calcium compounds Type de document : texte imprimé Auteurs : Josefa Fernandez, Auteur ; Fernando González, Auteur ; Carmen Pesquera, Auteur Année de publication : 2010 Article en page(s) : pp. 2986–2991 Note générale : Industrial Chemistry Langues : Anglais (eng) Mots-clés : Interaction--CO2/Sorbent--Sorbents--Mesoporous--Calcium Compounds Résumé : CO2 chemisorption experiments were used to study the behavior of sorbents prepared from MCM-41 and SBA-15 mesoporous supports and Ca(OH)2 at different ratios in two main aspects: to determine the capacity of the sorbents to capture CO2 and to identify the products synthesized in the process. Two different ways of preparation of the sorbents were used: Type I sorbents were prepared by mixing CaO, water, and the support at room temperature, and Type II were prepared by impregnation of the support with calcium nitrate followed by calcination and hydration to form Ca(OH)2. Static chemisorption experiments at low temperature (323 K) and low CO2 pressure showed that Type I yielded higher values of CO2 retention than Type II. MCM-41 support, with a higher specific surface area than SBA-15, achieved the more effective sorbent, 10% Ca(OH)2/MCM-41. The moles of CO2 per mole of calcium retained by this sorbent was approximately five times that obtained with unsupported commercial Ca(OH)2. To determine the form in which CO2 was retained at this low temperature dynamic chemisorption experiments with CO2 were performed with commercial Ca(OH)2 and with 10% Ca(OH)2/MCM-41 sorbent. The results showed that CO2 was chemisorbed on both solids as a complex CaO·CO2, which was reversibly desorbed at 473 K, and as CaCO3. The 10% Ca(OH)2/MCM-41 sorbent can be used as a regenerable sorbent at temperatures up to 823 K. At those conditions, only the CO2 retained as CaO·CO2 is desorbed, with no relevant loss of capture in the five cycles tested. Experiments varying the adsorption time proved that, in a first step, the CO2 retention is fast and probably kinetically controlled, making the further uptake much slower in a process controlled by diffusion; the maximum amount of CO2 retained (56.6% mol CO2/mol Ca) was obtained at 18 h of exposure with the sorbent prepared at the lowest Ca(OH)2/MCM-41 ratio tested (2.5%), showing that the reaction at low temperature is favored with a good calcium distribution. Note de contenu : Bibiogr. ISSN : 0885-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie901815u
in Industrial & engineering chemistry research > Vol. 49 N° 6 (Mars 2010) . - pp. 2986–2991[article] Study of the CO2/sorbent interaction in sorbents prepared with mesoporous supports and calcium compounds [texte imprimé] / Josefa Fernandez, Auteur ; Fernando González, Auteur ; Carmen Pesquera, Auteur . - 2010 . - pp. 2986–2991.
Industrial Chemistry
Langues : Anglais (eng)
in Industrial & engineering chemistry research > Vol. 49 N° 6 (Mars 2010) . - pp. 2986–2991
Mots-clés : Interaction--CO2/Sorbent--Sorbents--Mesoporous--Calcium Compounds Résumé : CO2 chemisorption experiments were used to study the behavior of sorbents prepared from MCM-41 and SBA-15 mesoporous supports and Ca(OH)2 at different ratios in two main aspects: to determine the capacity of the sorbents to capture CO2 and to identify the products synthesized in the process. Two different ways of preparation of the sorbents were used: Type I sorbents were prepared by mixing CaO, water, and the support at room temperature, and Type II were prepared by impregnation of the support with calcium nitrate followed by calcination and hydration to form Ca(OH)2. Static chemisorption experiments at low temperature (323 K) and low CO2 pressure showed that Type I yielded higher values of CO2 retention than Type II. MCM-41 support, with a higher specific surface area than SBA-15, achieved the more effective sorbent, 10% Ca(OH)2/MCM-41. The moles of CO2 per mole of calcium retained by this sorbent was approximately five times that obtained with unsupported commercial Ca(OH)2. To determine the form in which CO2 was retained at this low temperature dynamic chemisorption experiments with CO2 were performed with commercial Ca(OH)2 and with 10% Ca(OH)2/MCM-41 sorbent. The results showed that CO2 was chemisorbed on both solids as a complex CaO·CO2, which was reversibly desorbed at 473 K, and as CaCO3. The 10% Ca(OH)2/MCM-41 sorbent can be used as a regenerable sorbent at temperatures up to 823 K. At those conditions, only the CO2 retained as CaO·CO2 is desorbed, with no relevant loss of capture in the five cycles tested. Experiments varying the adsorption time proved that, in a first step, the CO2 retention is fast and probably kinetically controlled, making the further uptake much slower in a process controlled by diffusion; the maximum amount of CO2 retained (56.6% mol CO2/mol Ca) was obtained at 18 h of exposure with the sorbent prepared at the lowest Ca(OH)2/MCM-41 ratio tested (2.5%), showing that the reaction at low temperature is favored with a good calcium distribution. Note de contenu : Bibiogr. ISSN : 0885-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie901815u Exemplaires
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Titre : Experimental measurements and thermodynamic modeling of CO2 solubility at high pressure in model apple juices Type de document : texte imprimé Auteurs : Giovanna Ferrentino, Auteur ; Diego Barletta, Auteur ; Francesco Donsì, Auteur Année de publication : 2010 Article en page(s) : pp. 2992–3000 Note générale : Industrial Chemistry Langues : Anglais (eng) Mots-clés : Experimental--Measurements--Thermodynamic--Modeling--CO2--Solubility--Apple Juices--High--Pressure Résumé : High pressure carbon dioxide (HPCD) treatment can be used for the pasteurization of liquid foods. Solubility of CO2 in the liquid affects microbial inactivation. Measurement and prediction of CO2 solubility in a real or model system are of industrial relevance since the knowledge of the solubility limits will avoid the use of excess CO2. An experimental apparatus was set up to measure CO2 solubility in ternary mixtures of water−CO2−glucose and water−CO2−malic acid and in a quaternary mixture of water−CO2−malic acid−glucose at different concentrations of malic acid (0.01 and 2.68 g in 100 g of solution, corresponding to 7.5 × 10−5 and 0.02 mols in 100 mols of solution) and of glucose (4 and 12 g in 100 g of solution, corresponding to 0.02 and 0.07 mols in 100 mols of solution). CO2 solubility was also measured in a more complex solution of water−malic acid−ascorbic acid−pectin−glucose−sucrose, based on apple juice composition and in a commercial apple juice. The range of pressure tested was between 7.5 and 15.0 MPa while the temperature was between 308 and 333 K. CO2 solubility was inversely proportional to the glucose and sucrose concentration. Malic and citric acids only slightly affected CO2 solubility. Slight differences in the value of CO2 solubility were detected between the model solution and the real juice. The experimental results were compared with the equilibrium conditions evaluated using the process simulation software Aspen Plus. The vapor−liquid equilibrium was solved with the Peng−Robinson EOS, where the parameters were evaluated using Wong and Sandler mixing rules (PRWS), and the activity coefficients were defined using the functional groups with the modified UNIFAC method. The CO2 solubility values predicted by the model agreed well with the experimental data in the pressure and temperature range tested. Note de contenu : Bibiogr. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie9009974
in Industrial & engineering chemistry research > Vol. 49 N° 6 (Mars 2010) . - pp. 2992–3000[article] Experimental measurements and thermodynamic modeling of CO2 solubility at high pressure in model apple juices [texte imprimé] / Giovanna Ferrentino, Auteur ; Diego Barletta, Auteur ; Francesco Donsì, Auteur . - 2010 . - pp. 2992–3000.
Industrial Chemistry
Langues : Anglais (eng)
in Industrial & engineering chemistry research > Vol. 49 N° 6 (Mars 2010) . - pp. 2992–3000
Mots-clés : Experimental--Measurements--Thermodynamic--Modeling--CO2--Solubility--Apple Juices--High--Pressure Résumé : High pressure carbon dioxide (HPCD) treatment can be used for the pasteurization of liquid foods. Solubility of CO2 in the liquid affects microbial inactivation. Measurement and prediction of CO2 solubility in a real or model system are of industrial relevance since the knowledge of the solubility limits will avoid the use of excess CO2. An experimental apparatus was set up to measure CO2 solubility in ternary mixtures of water−CO2−glucose and water−CO2−malic acid and in a quaternary mixture of water−CO2−malic acid−glucose at different concentrations of malic acid (0.01 and 2.68 g in 100 g of solution, corresponding to 7.5 × 10−5 and 0.02 mols in 100 mols of solution) and of glucose (4 and 12 g in 100 g of solution, corresponding to 0.02 and 0.07 mols in 100 mols of solution). CO2 solubility was also measured in a more complex solution of water−malic acid−ascorbic acid−pectin−glucose−sucrose, based on apple juice composition and in a commercial apple juice. The range of pressure tested was between 7.5 and 15.0 MPa while the temperature was between 308 and 333 K. CO2 solubility was inversely proportional to the glucose and sucrose concentration. Malic and citric acids only slightly affected CO2 solubility. Slight differences in the value of CO2 solubility were detected between the model solution and the real juice. The experimental results were compared with the equilibrium conditions evaluated using the process simulation software Aspen Plus. The vapor−liquid equilibrium was solved with the Peng−Robinson EOS, where the parameters were evaluated using Wong and Sandler mixing rules (PRWS), and the activity coefficients were defined using the functional groups with the modified UNIFAC method. The CO2 solubility values predicted by the model agreed well with the experimental data in the pressure and temperature range tested. Note de contenu : Bibiogr. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie9009974 Exemplaires
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Titre : Development of soft sensor to identify flow regimes in horizontal pipe using digital signal processing technique Type de document : texte imprimé Auteurs : Kishore Muvvala, Auteur ; V. Kumar, Auteur ; B. C. Meikap, Auteur Année de publication : 2010 Article en page(s) : pp. 3001–3010 Note générale : Industrial Chemistry Langues : Anglais (eng) Mots-clés : Development--Sensor--Identify--Flow--Regimes--Horizontal--Pipe--Digital--Signal--Processing--Technique Résumé : The work described in this article is a new analytical and experimental study of two-phase gas−liquid horizontal flow in a conduit for flow pattern identification by a digital signal processing technique. The data are acquired online using a pressure transducer and a National Instruments data acquisition card. The true signal voltage changes rather smoothly as a function of the number of samples, whereas many kinds of noise are added; as a result, rapid, random changes in amplitude from point to point within the signal are observed. To reduce the noise, a smoothing technique is employed. In the smoothing, the data points of a signal are modified so that the individual points that are higher than the immediately adjacent points are reduced and points that are lower than the adjacent points are increased. This naturally leads to a smoother signal. For this purpose, the simplest smoothing algorithm, namely, a simple moving average, is employed and is able to successfully eliminate the noise. After eliminating the noise, the slope of the curve is continuously tracked to determine sudden or abrupt changes. It is interesting to note that, from the signal obtained, the slope is always decreasing in nature and the magnitude is on the order of 5 × 10−3. According to the data and the slope, different flow regimes can be identified by using cross-correlation method. Note de contenu : Bibiogr. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie9019215
in Industrial & engineering chemistry research > Vol. 49 N° 6 (Mars 2010) . - pp. 3001–3010[article] Development of soft sensor to identify flow regimes in horizontal pipe using digital signal processing technique [texte imprimé] / Kishore Muvvala, Auteur ; V. Kumar, Auteur ; B. C. Meikap, Auteur . - 2010 . - pp. 3001–3010.
Industrial Chemistry
Langues : Anglais (eng)
in Industrial & engineering chemistry research > Vol. 49 N° 6 (Mars 2010) . - pp. 3001–3010
Mots-clés : Development--Sensor--Identify--Flow--Regimes--Horizontal--Pipe--Digital--Signal--Processing--Technique Résumé : The work described in this article is a new analytical and experimental study of two-phase gas−liquid horizontal flow in a conduit for flow pattern identification by a digital signal processing technique. The data are acquired online using a pressure transducer and a National Instruments data acquisition card. The true signal voltage changes rather smoothly as a function of the number of samples, whereas many kinds of noise are added; as a result, rapid, random changes in amplitude from point to point within the signal are observed. To reduce the noise, a smoothing technique is employed. In the smoothing, the data points of a signal are modified so that the individual points that are higher than the immediately adjacent points are reduced and points that are lower than the adjacent points are increased. This naturally leads to a smoother signal. For this purpose, the simplest smoothing algorithm, namely, a simple moving average, is employed and is able to successfully eliminate the noise. After eliminating the noise, the slope of the curve is continuously tracked to determine sudden or abrupt changes. It is interesting to note that, from the signal obtained, the slope is always decreasing in nature and the magnitude is on the order of 5 × 10−3. According to the data and the slope, different flow regimes can be identified by using cross-correlation method. Note de contenu : Bibiogr. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie9019215 Exemplaires
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Titre : Temperature dependence of the dielectric properties of 2,2′-azobis(2-methyl-butyronitrile) (AMBN) Type de document : texte imprimé Auteurs : Smith, Alastair D., Auteur ; Edward H. Lester, Auteur ; Thurecht, Kristofer J., Auteur Année de publication : 2010 Article en page(s) : pp. 3011–3014 Note générale : Industrial Chermistry Langues : Anglais (eng) Mots-clés : Temperature--Dependence--Dielectric--Azobis--methyl--butyronitrile--AMBN Résumé : For the first time, the response of 2,2′-azobis(2-methyl-butyronitrile) (AMBN) to microwave heating at 2.45 GHz was studied by measuring its dielectric properties as a function of temperature with the observed variations being attributed to the physical form of the initiator, the 1 h decomposition half-life temperature, and the relaxation frequency. Note de contenu : Bibiogr. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie901389a
in Industrial & engineering chemistry research > Vol. 49 N° 6 (Mars 2010) . - pp. 3011–3014[article] Temperature dependence of the dielectric properties of 2,2′-azobis(2-methyl-butyronitrile) (AMBN) [texte imprimé] / Smith, Alastair D., Auteur ; Edward H. Lester, Auteur ; Thurecht, Kristofer J., Auteur . - 2010 . - pp. 3011–3014.
Industrial Chermistry
Langues : Anglais (eng)
in Industrial & engineering chemistry research > Vol. 49 N° 6 (Mars 2010) . - pp. 3011–3014
Mots-clés : Temperature--Dependence--Dielectric--Azobis--methyl--butyronitrile--AMBN Résumé : For the first time, the response of 2,2′-azobis(2-methyl-butyronitrile) (AMBN) to microwave heating at 2.45 GHz was studied by measuring its dielectric properties as a function of temperature with the observed variations being attributed to the physical form of the initiator, the 1 h decomposition half-life temperature, and the relaxation frequency. Note de contenu : Bibiogr. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie901389a Exemplaires
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Titre : Enhancement of rheological behavior of indian high ash coal−water suspension by using microwave pretreatment Type de document : texte imprimé Auteurs : B. K. Sahoo, Auteur ; S. De, Auteur ; M. Carsky, Auteur Année de publication : 2010 Article en page(s) : pp. 3015–3021 Note générale : Industrial Chemistry Langues : Anglais (eng) Mots-clés : Enhancement--Rheological--Behavior--High--Coal− Water--Suspension--Indian--Microwave Résumé : In this paper, rheological characteristics of coal−water slurries (CWS) by using microwave pretreatment have been presented. Detailed experimental investigations were carried out for two high ash Indian coals with 38 and 32% ash content. Experiments were conducted at the 900 W power level and various exposure times of 30, 60, 90, and 120 s. Before and after treatment, the samples were ground for rheological characteristic of CWS in an online Bohlin viscometer. All slurries were found to exhibit pseudoplastic characteristics and results indicate that the rheological properties of microwave-treated coal are better than untreated coal. The density of microwave-treated coal is less than that of untreated coal after grinding. A factorial plan was used, and empirical equations were obtained and found to be encouraging and highly significant. Note de contenu : Bibiogr. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie901770d
in Industrial & engineering chemistry research > Vol. 49 N° 6 (Mars 2010) . - pp. 3015–3021[article] Enhancement of rheological behavior of indian high ash coal−water suspension by using microwave pretreatment [texte imprimé] / B. K. Sahoo, Auteur ; S. De, Auteur ; M. Carsky, Auteur . - 2010 . - pp. 3015–3021.
Industrial Chemistry
Langues : Anglais (eng)
in Industrial & engineering chemistry research > Vol. 49 N° 6 (Mars 2010) . - pp. 3015–3021
Mots-clés : Enhancement--Rheological--Behavior--High--Coal− Water--Suspension--Indian--Microwave Résumé : In this paper, rheological characteristics of coal−water slurries (CWS) by using microwave pretreatment have been presented. Detailed experimental investigations were carried out for two high ash Indian coals with 38 and 32% ash content. Experiments were conducted at the 900 W power level and various exposure times of 30, 60, 90, and 120 s. Before and after treatment, the samples were ground for rheological characteristic of CWS in an online Bohlin viscometer. All slurries were found to exhibit pseudoplastic characteristics and results indicate that the rheological properties of microwave-treated coal are better than untreated coal. The density of microwave-treated coal is less than that of untreated coal after grinding. A factorial plan was used, and empirical equations were obtained and found to be encouraging and highly significant. Note de contenu : Bibiogr. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie901770d Exemplaires
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Titre : Fragment-based approach for estimating thermophysical properties of fats and vegetable oils for modeling biodiesel production processes Type de document : texte imprimé Auteurs : Li Zong, Auteur ; Ramanathan, Sundaram, Auteur ; Chau-Chyun Chen, Auteur Année de publication : 2010 Article en page(s) : pp. 3022–3023 Note générale : Industrial Chemistry Langues : Anglais (eng) Mots-clés : Fragment--Based--Approach--Estimating--Thermophysical-- Fats--Vegetable--Oils--Modeling--Biodiesel--Production--Processes ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie100160v
in Industrial & engineering chemistry research > Vol. 49 N° 6 (Mars 2010) . - pp. 3022–3023[article] Fragment-based approach for estimating thermophysical properties of fats and vegetable oils for modeling biodiesel production processes [texte imprimé] / Li Zong, Auteur ; Ramanathan, Sundaram, Auteur ; Chau-Chyun Chen, Auteur . - 2010 . - pp. 3022–3023.
Industrial Chemistry
Langues : Anglais (eng)
in Industrial & engineering chemistry research > Vol. 49 N° 6 (Mars 2010) . - pp. 3022–3023Exemplaires
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