Study on supported LaCoO3 catalysts for diesel soot combustion
WANG Yan, ZHAO Wen- yi, ZHANG Cheng, WANG Yu,ZHANG Xu- xia, LI Zhao- qiang
1. Baotou Research Institute of Rare Earths, Baotou 014030, Nei Mongol, China 2. National Engineering Research of Rare Earth Metallurgy and Functional Materials, Baotou 014030, Nei Mongol,China 3. State Key Laboratory of Baiyunobo Rare Earth Resource Researches and Comprehensive Utilization, Baotou 014030, Nei Mongol, China
Abstract：A series of LaCoO3 catalysts supported on different carriers including Al2O3, TiO2, ZrO2, CeO2, Ce0. 9Zr0. 1Ox and Ce0. 9RE0. 1Ox (RE=La, Pr, Nd, Sm and Y) was prepared by the method of coprecipitation- impregnation method. The structures and properties of the samples were characterized by the techniques of XRD and BET. The catalytic performance of the prepared supports and catalysts for soot combustion emitted from diesel engines was investigated. The results show that the supported LaCoO3 catalysts posse much higher activity than relevant supports. The catalytic performance follows the order of LaCoO3/CeSmOx>LaCoO3/CeYOx=LaCoO3/CeNdOx>LaCoO3/CeLaOx>LaCoO3/CeO2>LaCoO3/CePrOx>LaCoO3/CeZrOx>LaCoO3/TiO2>LaCoO3/Al2O3. The peak combustion temperature of soot particles over LaCoO3/CeSmOx catalyst is 341℃, which exhibits best soot oxidation ability among the supported catalysts when the contact between catalysts and soot are loose.
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2017, Vol. 24 
