High thermal stability of ceria-based mixed oxidecatalysts supported on ZrO2 for toluene combustion

Abstract

Cu–Mn–Ce mixed oxide catalysts (CMCs) supported on ZrO₂ were prepared by an impregnation method. Their catalytic activity was evaluated by a model reaction, that of toluene combustion. 5% CMC/ZrO₂ catalysts show a very high activity and thermal stability, and 90% of toluene conversion could be obtained at temperatures below 260 °C, even with the catalyst being annealed at 900 °C. A new phase of Zr_0.88Ce_0.12O₂ in the interface was formed by the interaction between ZrO₂ and CMC on the catalyst with low loading. Zr_0.88Ce_0.12O₂ serves as the actual carrier of the active phase, and can significantly improve the thermal stability of the catalyst.