Catalytic oxidation of soot particulates over MnO_x-CeO_2 oxides prepared by complexation-combustion method  

作　　者：Wenjuan Shan, Na Ma, Jiali Yang, Xiaowei Dong, Chang Liu, Lingling Wei Institute of Chemistry for Functionalized Materials, College of Chemistry and Chemical Engineering, Liaoning Normal University, Dalian 116029, Liaoning, China 

出　　处：《Journal of Natural Gas Chemistry》2010年第1期86-90,共5页天然气化学杂志（英文版）

基　　金：supported by the Key Project of National Natural Science Foundation of China (No. 20603016);Liaoning Provincial Science &Technology Project of China (No. 20071074) for financial support of this research

摘　　要：MnOx-CeO2 oxides prepared by complexation-combustion method were used for soot oxidation. The highest conversion rate of soot was obtained on a MnOx-CeO2 oxide prepared under mild acid condition of pH = 4, where the oxidation temperature corresponding to maximum activity was decreased more than 150 ℃ compared with that of un-catalytic soot oxidation. The structure and property of the catalysts were investigated by X-ray powder diffraction （XRD） and temperature programmed reduction （TPR）. The results indicated that there were at least two kinds of Mn species present in MnOx-CeO2 catalysts, i.e. Mn ions within CeO2 lattice and high dispersion MnOx on the surface of CeO2. The presence of Mn ions in the CeO2 lattice improved the oxygen vacancy due to the charge difference, and the CeO2 considerably decreased the reduction temperature of MnOx. The capability to activate oxygen through the oxygen exchange between O2 in gas phase and lattice oxygen species in MnOx-CeO2 oxide contributed to the high catalytic activity for the reaction.MnOx-CeO2 oxides prepared by complexation-combustion method were used for soot oxidation. The highest conversion rate of soot was obtained on a MnOx-CeO2 oxide prepared under mild acid condition of pH = 4, where the oxidation temperature corresponding to maximum activity was decreased more than 150 ℃ compared with that of un-catalytic soot oxidation. The structure and property of the catalysts were investigated by X-ray powder diffraction （XRD） and temperature programmed reduction （TPR）. The results indicated that there were at least two kinds of Mn species present in MnOx-CeO2 catalysts, i.e. Mn ions within CeO2 lattice and high dispersion MnOx on the surface of CeO2. The presence of Mn ions in the CeO2 lattice improved the oxygen vacancy due to the charge difference, and the CeO2 considerably decreased the reduction temperature of MnOx. The capability to activate oxygen through the oxygen exchange between O2 in gas phase and lattice oxygen species in MnOx-CeO2 oxide contributed to the high catalytic activity for the reaction.

关 键 词：soot oxidation MnOx-CeO2 oxides active oxygen 

分 类 号：O643.32[理学—物理化学]