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Design and economic analysis of the process for biodiesel fuel production from transesterificated rapeseed oil using supercritical methanol / Youngsub Lim in Industrial & engineering chemistry research, Vol. 48 N° 11 (Juin 2009) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 48 N° 11 (Juin 2009) . - pp. 5370–5378 Titre : Design and economic analysis of the process for biodiesel fuel production from transesterificated rapeseed oil using supercritical methanol Type de document : texte imprimé Auteurs : Youngsub Lim, Auteur ; Hong-shik Lee, Auteur ; Youn Woo Lee, Auteur Année de publication : 2009 Article en page(s) : pp. 5370–5378 Note générale : Chemical engineering Langues : Anglais (eng) Mots-clés : Biodiesel  fuel  production  Alkali-catalyzed  process  Supercritical  biodiesel  process Résumé : A supercritical process for biodiesel fuel production is generally known to be less profitable than the alkali-catalyzed process due to high temperature and pressure requirements for the supercritical reaction. Only a few approaches have been proposed using experimental results to design a supercritical biodiesel process and to assess its profitability compared to the alkali-catalyzed process. In this study, a design for a supercritical biodiesel process was suggested and its economic performance with three different reaction conditions was simulated in the comparison with the conventional alkali-catalyzed process. It was found that the total capital cost was higher in all three cases of the supercritical process than in the alkali-catalyzed process due to the high cost of pumps, heaters, and heat exchangers. However, the total manufacturing cost of the supercritical process was lower than that of the alkali-catalyzed process due to the higher glycerol credit and the lack of a requirement for catalyst or solvent. The supercritical process can produce high-purity glycerol more easily that does not contain any water, which is unavoidable in the washing step of the alkali-catalyzed process. The higher steam cost in the supercritical process was compensated for by catalyst and solvent costs in the alkali-catalyzed process. Overall, one of the supercritical processes resulted in shorter payout time than the alkali-catalyzed process even when virgin oil was used as one of the raw materials, because the lower total manufacturing cost made up for the increased total capital cost. En ligne : http://pubs.acs.org/doi/abs/10.1021/ie8005287 [article] Design and economic analysis of the process for biodiesel fuel production from transesterificated rapeseed oil using supercritical methanol [texte imprimé] / Youngsub Lim, Auteur ; Hong-shik Lee, Auteur ; Youn Woo Lee, Auteur . - 2009 . - pp. 5370–5378. Chemical engineering Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 48 N° 11 (Juin 2009) . - pp. 5370–5378 Mots-clés : Biodiesel  fuel  production  Alkali-catalyzed  process  Supercritical  biodiesel  process Résumé : A supercritical process for biodiesel fuel production is generally known to be less profitable than the alkali-catalyzed process due to high temperature and pressure requirements for the supercritical reaction. Only a few approaches have been proposed using experimental results to design a supercritical biodiesel process and to assess its profitability compared to the alkali-catalyzed process. In this study, a design for a supercritical biodiesel process was suggested and its economic performance with three different reaction conditions was simulated in the comparison with the conventional alkali-catalyzed process. It was found that the total capital cost was higher in all three cases of the supercritical process than in the alkali-catalyzed process due to the high cost of pumps, heaters, and heat exchangers. However, the total manufacturing cost of the supercritical process was lower than that of the alkali-catalyzed process due to the higher glycerol credit and the lack of a requirement for catalyst or solvent. The supercritical process can produce high-purity glycerol more easily that does not contain any water, which is unavoidable in the washing step of the alkali-catalyzed process. The higher steam cost in the supercritical process was compensated for by catalyst and solvent costs in the alkali-catalyzed process. Overall, one of the supercritical processes resulted in shorter payout time than the alkali-catalyzed process even when virgin oil was used as one of the raw materials, because the lower total manufacturing cost made up for the increased total capital cost. En ligne : http://pubs.acs.org/doi/abs/10.1021/ie8005287

Solid-state polymerization of semiaromatic copolyamides of nylon-4,T and Nylon-4,6 / Young Jun Kim in Industrial & engineering chemistry research, Vol. 51 N° 49 (Décembre 2012) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 51 N° 49 (Décembre 2012) . - pp. 15801–15810 Titre : Solid-state polymerization of semiaromatic copolyamides of nylon-4,T and Nylon-4,6 : Composition ratio effect and thermal properties Type de document : texte imprimé Auteurs : Young Jun Kim, Auteur ; Kurnia Endah Yohana, Auteur ; Hong-shik Lee, Auteur Année de publication : 2013 Article en page(s) : pp. 15801–15810 Note générale : Industrial chemistry Langues : Anglais (eng) Mots-clés : Thermal  properties  Polymerization Résumé : Solid-state polymerization (SSP) of semiaromatic copolyamides composed of nylon-4,T and nylon-4,6 in different molar ratios were investigated using a mixture of nitrogen and steam as the sweep fluid at reaction temperatures in the range of 220–260 °C. Prepolymers having different nylon-4,T contents (28.2, 37.9, and 47.8 mol %) were synthesized by melt polyamidation with stoichiometric ratios of diamine and diacid. The SSP conditions were carefully chosen to eliminate the influences of both internal and external diffusion of the reaction byproducts. Under these conditions, a high-molecular-weight semiaromatic copolyamide with an intrinsic viscosity of 2.469 dL/g was obtained upon SSP at 260 °C for 48 h. As the nylon-4,T content increased, the SSP rate decreased owing to the inherently low reactivity of the aromatic diacid and inhibition of chain-end mobility. The glass transition, melting, and decomposition temperatures of the polymers synthesized from the higher-nylon-4,T-content prepolymer were always higher than those of the polymers synthesized from the lower-nylon-4,T-content prepolymer. ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=26732105 [article] Solid-state polymerization of semiaromatic copolyamides of nylon-4,T and Nylon-4,6 : Composition ratio effect and thermal properties [texte imprimé] / Young Jun Kim, Auteur ; Kurnia Endah Yohana, Auteur ; Hong-shik Lee, Auteur . - 2013 . - pp. 15801–15810. Industrial chemistry Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 51 N° 49 (Décembre 2012) . - pp. 15801–15810 Mots-clés : Thermal  properties  Polymerization Résumé : Solid-state polymerization (SSP) of semiaromatic copolyamides composed of nylon-4,T and nylon-4,6 in different molar ratios were investigated using a mixture of nitrogen and steam as the sweep fluid at reaction temperatures in the range of 220–260 °C. Prepolymers having different nylon-4,T contents (28.2, 37.9, and 47.8 mol %) were synthesized by melt polyamidation with stoichiometric ratios of diamine and diacid. The SSP conditions were carefully chosen to eliminate the influences of both internal and external diffusion of the reaction byproducts. Under these conditions, a high-molecular-weight semiaromatic copolyamide with an intrinsic viscosity of 2.469 dL/g was obtained upon SSP at 260 °C for 48 h. As the nylon-4,T content increased, the SSP rate decreased owing to the inherently low reactivity of the aromatic diacid and inhibition of chain-end mobility. The glass transition, melting, and decomposition temperatures of the polymers synthesized from the higher-nylon-4,T-content prepolymer were always higher than those of the polymers synthesized from the lower-nylon-4,T-content prepolymer. ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=26732105