铈钛氧化物载体对La0.8Ce0.2MnO3催化燃烧甲苯性能的影响

以复合氧化物CeO2 TiO2为载体、La08Ce02MnO3为活性组分,采用等体积浸渍法制备了氧化物负载型催化剂La08Ce02MnO3/CeO2 TiO2(记为La/CexTi)。以甲苯为模型污染物,考察了载体的制备方法、nCe/nTi、焙烧温度、钙钛矿负载量对催化剂活性的影响。并采用XRD对催化剂进行了表征分析。结果表明,以共沉淀法制备的CeO2 TiO2作为载体负载钙钛矿活性组分制备的La/CexTi催化剂表现出较高的催化活性;当采用载体中nCe/nTi为05、活性组分负载质量分数为20%、焙烧温度为600℃时制备的La/CexTi催化剂,甲苯完全转化温度为240℃。CeO2 TiO2复合氧化物载体以非晶态CexTi1 xO2固溶体形式存在,钙钛矿均匀分散在载体的表面,载体对于催化剂活性的提高起到协同效应。

Effect of Cerium-Titanium Oxide Support on Catalytic Combustion of Toluene Performance of La0.8Ce0.2MnO3

Supported perovskite catalysts La08Ce02MnO3/CeO2 TiO2 named La/CexTi were prepared by incipient wetness impregnation by using CeO2 TiO2 mixed oxide and La08Ce02MnO3 as the support and active phase, respectively. The effects of support preparation method, nCe/nTi, calcination temperature and the perovskite loading on the catalytic performance of La/CexTi  in catalytic combustion of toluene were investigated. The catalysts were characterized by XRD. The results showed that the support prepared by coprecipitation was a suitable carrier for La/CexTi catalyst, which possessed the better catalytic activity in toluene combustion. By using the La/CexTi, prepared with the nCe/nTi of 05, loading capacity of 20%,and the calcination temperature of 600℃, as catalyst, the complete combustion temperature of toluene was only 240℃. In La/CexTi catalyst CeO2 TiO2 existed in the form of amorphous solid solution and the perovskite uniformly dispersed in the surface of CeO2 TiO2. The synergistic interaction between the active phase and the carrier played an important role in the catalyst activity enhancement.