Catalytic Properties Of Perovskite Rare Earth Composite Oxide Prepared On New Carrier For CO+NO

In order to research activity of perovskite rare earth composite oxide on the macroporous SiO₂ carrier, La_0.8Sr_0.2CoO₃ was prepared by impregnation method and sol-gel method. At the same time, Ce, Mn, Cu, Fe, etc elements were replaced and doped in A, B bits, and synthesis conditions were optimized through the single factor analysis method. Through XRD, SEM, BET, XPS and catalytic properties test for CO+NO, preparation and structure of these oxides were discussed and researched in this article.Experimental results show that only La_0.8Sr_0.2CoO₃ formed perovskite type structure in the La_0.8Sr_0.2CoO₃/SiO₂ system of different load rate and the La_0.8Sr_0.2MO₃/SiO₂(M= Cu, Fe, Mn, Co) system, which prepared by impregnation method. Catalyst in each sample appears on the carrier surface in the form of coating, specific surface area of sample reduce when the load rate of sample increase. The sample with 50.47% load rate has the best catalytic activity for CO+NO in the La_0.8Sr_0.2CoO₃/SiO₂ system of different load rate, the sample La_0.8Sr_0.2CoO₃ has the best catalytic activity for CO+NO in the La_0.8Sr_0.2MO₃/SiO₂(M= Cu, Fe, Mn, Co) system.Experimental results show that all samples formed perovskite type structure in the La_0.8Sr_0.2CoO₃/SiO₂ system of different load rate and the La_0.8Sr_0.2-xCe_xCo_1-yFe_yO₃/SiO₂(x=0-0.2,y=0.2-0.8) system, which prepared by sol-gel method. CeO₂ crystalling phase was formed in the samples contained Ce. Catalyst in each sample appears on the carrier surface in the form of particles, specific surface area of sample reduce when the load rate of sample increase. The sample with 72.77% load rate has the best catalytic activity for CO+NO in the La_0.8Sr_0.2CoO₃/SiO₂ system of different load rate, the sample La_0.8Ce_0.2Co_0.6Fe_0.4O₃ has the best catalytic activity for CO+NO in the La_0.8Sr_0.2-xCe_xCo_1-yFe_yO₃/SiO₂(x=0-0.2,y=0.2-0.8) system.