Preparation And Investigation On Three Way Catalytic Properties Of Copper Base Composite Oxide Of Ba

Recently, the automobile industry in the world is developing fast, but the pollution from exhaust gas is more and more serious. Automobile sales of China, has exceeds that of Japan in 2005 to be the second automobile country, and exceeds that of America in the first quarter of 2009 to be the largest automobile country. However, automobile exhaust gas standards started late in China, and fall behind Europe, America and some other countries, such as exhaust gas cleaning technology. Therefore, it is extremely needed to research own technology on automobile exhaust gas cleaning catalyst for China. Nowadays, almost catalysts used in foreign countries take precious metal Pt, Pd and Rh as active components, which are rare in China. Rare earth is rich in China, therefore, it is important to research rare earth or transition metal for us.In this paper, we used Cu as the active component and added BaO into Ceria-Zirconia Solid Solution using co-precipitation method. It can be formed into Ceria-Zirconia-Barium solid solution. We studied Cu-based catalyst on this solid solution.We prepared catalysts using two different ways of co-precipitation and impregnation. It's proved that the impregnation is better for preparing Cu-Ce-Zr-Ba-O mixed oxides. We used NH4HCO3 as the precipitator. The Cu-Ce-Zr-Ba-O catalyst with Ce:Zr molar ratio of 0.2:0.8,the content of Ba of 4%(weight) and the content of Cu of 5%(weight) showed the best three-way catalytic performance. When the air/fuel ratio was 1.40, under the condition of excess oxygen, the light-off temperature for C3H6, CO and NO were 250℃,153℃and 312℃respectively. After aging at 900℃, the catalysts still hold good catalytic activity. The results of XRD,DTA and SEM characterization showed some Cu and Ba entered the Ce-Zr solid solution to form a Cu-Ce-Zr-Ba solid solution, it help to increase the catalytic activity and thermal stability of the Cu/Ce0.2Zr0.8Bao.o4O2-λcatalyst.