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Rate expression for water–gas shift over a gold/ferrochrome catalyst / Gaurav N. Vajani in Industrial & engineering chemistry research, Vol. 50 N° 18 (Septembre 2011) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 50 N° 18 (Septembre 2011) . - pp. 10493-10499 Titre : Rate expression for water–gas shift over a gold/ferrochrome catalyst Type de document : texte imprimé Auteurs : Gaurav N. Vajani, Auteur ; Shea Lerk Ng, Auteur ; Carl R. F. Lund, Auteur Année de publication : 2011 Article en page(s) : pp. 10493-10499 Note générale : Chimie industrielle Langues : Anglais (eng) Mots-clés : Catalyst  Water  gas Résumé : The kinetics of low-temperature water―gas shift over gold/ferrochrome catalysts were studied at atmospheric pressure and temperatures between 160 and 180 °C. During two extended kinetic experiments lasting 903 and 1313 h, the activity of the catalyst decreased by 52% and 78%, respectively. The corresponding changes in the Brunauer-Emmett-Teller surface areas were 16% and 12%, respectively, suggesting that changes in the support surface area are not the primary cause for deactivation. The use of a bracketing technique, wherein the system was regularly returned to a standard set of reaction conditions, allowed the rate expression to be written as the product of an activity factor, which accounted for catalyst deactivation, and a power-law rate expression, which accounted for the dependence of the reaction rate upon temperature and composition. The power-law kinetic expression, including a term to account for the approach to equilibrium, was found to describe the kinetics of the reaction reasonably welL The resulting reaction orders were 0.39 for CO, 0.99 for H2O, -0.28 for CO2, and ―0.25 for H2, and the apparent activation energy was equal to 88.2 kJ/mol. DEWEY : 660 ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=24523871 [article] Rate expression for water–gas shift over a gold/ferrochrome catalyst [texte imprimé] / Gaurav N. Vajani, Auteur ; Shea Lerk Ng, Auteur ; Carl R. F. Lund, Auteur . - 2011 . - pp. 10493-10499. Chimie industrielle Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 50 N° 18 (Septembre 2011) . - pp. 10493-10499 Mots-clés : Catalyst  Water  gas Résumé : The kinetics of low-temperature water―gas shift over gold/ferrochrome catalysts were studied at atmospheric pressure and temperatures between 160 and 180 °C. During two extended kinetic experiments lasting 903 and 1313 h, the activity of the catalyst decreased by 52% and 78%, respectively. The corresponding changes in the Brunauer-Emmett-Teller surface areas were 16% and 12%, respectively, suggesting that changes in the support surface area are not the primary cause for deactivation. The use of a bracketing technique, wherein the system was regularly returned to a standard set of reaction conditions, allowed the rate expression to be written as the product of an activity factor, which accounted for catalyst deactivation, and a power-law rate expression, which accounted for the dependence of the reaction rate upon temperature and composition. The power-law kinetic expression, including a term to account for the approach to equilibrium, was found to describe the kinetics of the reaction reasonably welL The resulting reaction orders were 0.39 for CO, 0.99 for H2O, -0.28 for CO2, and ―0.25 for H2, and the apparent activation energy was equal to 88.2 kJ/mol. DEWEY : 660 ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=24523871