Promoting effect of ZrO2 carrier on activity and thermal stability of CeO2-based oxides catalysts for toluene combustion

ZrO2 was used as a support for the preparation of Cu-Mn-Ce mixed oxides catalysts (CMC) by impregnation method and calcination at different temperatures. A model reaction, toluene combustion was conducted to evaluate the performance of CMC/ZrO2 catalysts. High thermal stability and activity was obtained on these catalysts. The effects of CMC loading and calcination temperature on the structure and redox properties of catalysts were also investigated by XRD, H-2-TPR, TEM and XPS. Results show that calcination leads to the interaction of ZrO2 and CMC via the formation of a new phase of Zr0.88Ce0.12O2 in the interface, which is more likely to be formed in the catalysts with low CMC loading levels. Zr0.88Ce0.12O2 seems to function as the actual carrier of active phase of CMC, which cannot only stabilize the surface active structure of CMC but also enhance the mobility of active oxygen and improve the catalytic performance of total oxidation as well. (C) 2013 Elsevier B.V. All rights reserved.