Kinetic study of propane dehydrogenation and catalyst deactivation over Pt-Sn/Al_2O_3catalyst

• 作 者: Farnaz Tahriri Zangeneh Abbas Taeb Khodayar Gholivand Saeed Sahebdelfar
• 机 构: Department of Chemistry, Science and Research Branch, Islamic Azad University,Catalyst Research Grou
• 出 处: Journal of Energy Chemistry
• 发表日期: 2013年05期
• 关键词: propane kinetics insensitive fluctuation selectivity fitted otherwise propylene

The kinetics of propane dehydrogenation and catalyst deactivation over Pt-Sn/Al2O3 catalyst were studied.Performance test runs were carried out in a fixed-bed integral reactor.Using a power-law rate expression for the surface reaction kinetics and independent law for deactivation kinetics,the experimental data were analyzed both by integral and a novel differential method of analysis and the results were compared.To avoid fluctuation of time-derivatives of conversion required for differential analysis,the conversion-time data were first fitted with appropriate functions.While the time-zero and rate constant of reaction were largely insensitive to the function employed,the rate constant of deactivation was much more sensitive to the function form.The advantage of the proposed differential method,however,is that the integration of the rate expression is not necessary which otherwise could be complicated or impossible.It was also found that the reaction is not limited by external and internal mass transfer limitations,implying that the employed kinetics could be considered as intrinsic ones.

The kinetics of propane dehydrogenation and catalyst deactivation over Pt-Sn / Al2O3 catalyst were studied. Performance test were performed out in a fixed-bed integral reactor. Using a power-law rate expression for the surface reaction kinetics and independent law for deactivation kinetics , the experimental data were extracted both by integral and a novel differential method of analysis and the results were compared. To avoid fluctuation of time-derivatives of conversion required for differential analysis, the conversion-time data were first fitted with appropriate functions. Whilst the time-zero and rate constant of reaction were substantially insensitive to the function employed, the rate constant of deactivation was much more sensitive to the function form. advantage; the proposed differential method, however, is that the integration of the rate expression is not necessary which otherwise could be complicated or impossible. It was also found that the reaction is not limited by external and inte rnal mass transfer limitations, implying that the employed kinetics could be considered as intrinsic ones.