NO reduction by CO over CoOx/CeO2 catalysts: Effect of support calcination temperature on activity

Abstract

CeO2 supported CoOx catalysts showed promising results in many NO reduction processes including NO reduction by CO. In this work, a series of CeO2 supports with different calcination temperatures (as received-800 °C calcination) were prepared, followed by the synthesis of a series of CoOx/CeO2 catalysts with a surface density of 2.5 Co/nm2 using the incipient wetness impregnation method. To understand the physicochemical properties of catalysts, various characterizations techniques, including BET, Raman spectroscopy, XRD, and H2-TPR, were performed. The results showed that as calcination temperature increased, physical properties of supporting materials were changed. Surface CoOx improved the reducibility of CeO2, but it was not affected by the support calcination temperatures confirmed by H2-TPR. The presence of CoOx was crucial to enhance the catalytic activity during the NO reduction by CO reaction, rather than physical properties (surface area, pore size, particle size) of the catalyst.