Kinetic Modeling Of Oxidative Steam Reforming Of Methanol Over Cu/ZnO/CeO2/AL2O3 Catalyst

Abstract

A kinetic model for oxidative steam reforming ofmethanol (OSRM) has been developed using Langmuir– Hinshelwood (LH) approach over Cu/ZnO/CeO2/Al2O3 catalyst. The kineticmodel incorporates the partial oxidation of methanol, steam reforming of methanol and reverse water–gas shift reactions for the OSRM process. Kinetics study was performed over a wide range of reaction temperatures and contact-times in an integral reactor under the chemical reaction-controlled regime. Three intrinsic Langmuir– Hinshelwood kinetic models were developed based on the two proposed reaction mechanisms. The appropriate kinetic model for OSRM has been obtained after rigorous parameter estimation and model discrimination among all the three kinetic models. Parameters were estimated by non-linear least square regression. The correlations among them were minimized by temperature centering of Arrhenius and van’t Hoff equations. A good agreement was obtained between experimental and model predicted results for the LH kinetic model based on formation of formate from oxymethylene, dissociation of formic acid, and formation of adsorbed CO and surface hydroxyls from formate species as the ratedetermining steps for methanol partial oxidation, methanol steam reforming and reverse water–gas shift reactions respectively.