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Ethylbenzene transformation over a ZSM-5-based catalyst in a riser simulator / Al-Khattaf, S. in Industrial & engineering chemistry research, Vol. 48 N° 6 (Mars 2009) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 48 N° 6 (Mars 2009) . - pp. 2836–2843 Titre : Ethylbenzene transformation over a ZSM-5-based catalyst in a riser simulator Type de document : texte imprimé Auteurs : Al-Khattaf, S., Auteur ; N. M. Tukur, Auteur ; S. Rabiu, Auteur Année de publication : 2009 Article en page(s) : pp. 2836–2843 Note générale : Chemical engineering Langues : Anglais (eng) Mots-clés : Ethylbenzene  transformation  ZSM-5-type  catalyst  Fluidized-bed  reactor  Cracking Résumé : The transformation of ethylbenzene has been studied over a ZSM-5-type catalyst in a riser simulator that mimics the operation of a fluidized-bed reactor. The study was conducted at 350, 375, 400, 450, and 500 °C for reaction times of 3, 5, 7, 10, 13, and 15 s. The effect of reaction conditions on the ratio of cracking to disproportionation products (C/D), the distribution of diethylbenzene (DEB) isomers (m-DEB and p-DEB), and the ratio of benzene/diethylbenzenes (B/DEB) are reported. The experimental results were modeled using quasi-steady-state approximation. Disproportionation was determined to dominate at low temperatures (350−400 °C), while cracking reaction becomes significant as higher temperatures (>400 °C). Thus, two mechanisms were postulated to represent the disappearance of ethylbenzene during the transformation reaction (one mechanism for low temperature, and another for the complete temperature range considered). Kinetic parameters that were used for the disappearance of ethylbenzene during the transformation reaction, and in its conversion into cracking and disproportionation products, were calculated using the catalyst activity decay function, based on the time-on-stream (TOS). The apparent activation energies were determined to decrease: Ecracking > Edisproportionation. En ligne : http://pubs.acs.org/doi/abs/10.1021/ie801609x [article] Ethylbenzene transformation over a ZSM-5-based catalyst in a riser simulator [texte imprimé] / Al-Khattaf, S., Auteur ; N. M. Tukur, Auteur ; S. Rabiu, Auteur . - 2009 . - pp. 2836–2843. Chemical engineering Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 48 N° 6 (Mars 2009) . - pp. 2836–2843 Mots-clés : Ethylbenzene  transformation  ZSM-5-type  catalyst  Fluidized-bed  reactor  Cracking Résumé : The transformation of ethylbenzene has been studied over a ZSM-5-type catalyst in a riser simulator that mimics the operation of a fluidized-bed reactor. The study was conducted at 350, 375, 400, 450, and 500 °C for reaction times of 3, 5, 7, 10, 13, and 15 s. The effect of reaction conditions on the ratio of cracking to disproportionation products (C/D), the distribution of diethylbenzene (DEB) isomers (m-DEB and p-DEB), and the ratio of benzene/diethylbenzenes (B/DEB) are reported. The experimental results were modeled using quasi-steady-state approximation. Disproportionation was determined to dominate at low temperatures (350−400 °C), while cracking reaction becomes significant as higher temperatures (>400 °C). Thus, two mechanisms were postulated to represent the disappearance of ethylbenzene during the transformation reaction (one mechanism for low temperature, and another for the complete temperature range considered). Kinetic parameters that were used for the disappearance of ethylbenzene during the transformation reaction, and in its conversion into cracking and disproportionation products, were calculated using the catalyst activity decay function, based on the time-on-stream (TOS). The apparent activation energies were determined to decrease: Ecracking > Edisproportionation. En ligne : http://pubs.acs.org/doi/abs/10.1021/ie801609x