Kinetic and Effectiveness Factor for Methanol Steam Reforming over CuO-ZnO-Al2O3 Catalysts

CuO-ZnO-Al2O3 촉매에서의 메탄올 수증기 개질반응에 대한 반응속도와 유효성인자

  • Published : 2002.09.15

Abstract

Kinetic and effectiveness factors for methanol steam reforming using commercial copper-containing catalysts in a plug flow reactor were investigated over the temperature ranges of $180-250^{\circ}C$ at atmospheric pressure. The selectivity of $CO_2$/$H_2$ was almost 100%, and CO products were not observed under reaction conditions employed in this work. It was indicated that $CO_2$ was directly produced and CO was formed via the reverse water gas shift reaction after methanol steam reforming. The intrinsic kinetics for such reactions were well described by the Langmuir-Hinshelwood model based on the dual-site mechanism. The six parameters in this model, including the activation energy of 103kJ/mol, were estimated from diffusion-free data. The significant effect of internal diffusion was observed for temperature higher than $230^{\circ}C$ or particle sizes larger than 0.36mm. In the diflusion-limited case, this model combined with internal effectiveness factors was also found to be good agreement with experimental data.

Keywords

Kinetic;Effectiveness factor;Diffusion limitation;Langmuir-Hinshelwood model;Methanol steam reforming;Copper-based catalyst

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