A series of ZrxTi1-xO2 (x = 0, 0.1, 0.5, 0.9, 1.0) mixed oxides were prepared by the co-precipitation method and were used as supports to prepare Pt/ZrxTi1-xO2 catalysts by impregnation with H2PtCl6 solution. The catalysts were characterized by N2 adsorption, X-ray diffiaction-desorption, X-ray photoelectron spectroscopy, H2 temperature-programmed reduction, and NH3 temperature-programmed desorp-tion. The results indicated that the dominative crystalline phase of ZrxTi1-xO2 is anatase and it has higher specific surface area (94 m2/g) and larger pore volume (0.33 cmVg). Compared with the Pt/ZrxTi1-xO2 = 0, 0.5, 0.9, 1.0) catalysts, Pt/ZrxTi1-xO2 shows excellent catalytic activity (750 of HC and CO are 185 and 174 ℃, respectively, and T90 of HC and CO are 197 and 201 ℃, respectively) and low-level oxidation activity of SO2 (the SO2 conversion at 350 ℃ is only 25.5%).%采用共沉淀法制备了一系列ZrxTi1-xO2(x=0.0,0.1,0.5,0.9,1.0)复合氧化物,并以此为载体,用等孔体积浸渍H2PtCl6制得Pt/ZrxTi1-xO2柴油车氧化催化剂.运用N2吸附-脱附,X射线多晶粉末衍射,X射线光电子能谱,H2程序升温还原和NH3程序升温脱附等手段对催化剂进行了表征.结果表明,在系列催化剂样品中,Zr0.1Ti0.9O2复合氧化物主要以锐钛矿形式存在,具有较好的织构性能,样品的比表面积达94 m2/g,孔体积为0.33 cm3/g.相应地,Pt/Zr0.1 Ti0.9O2催化剂表现出优异的催化氧化性能,HC和CO的起燃温度(T50)分别为185和174 ℃,完全转化温度(T90)分别为197和201℃；且具有较低的SO2氧化活性,350℃时SO2仅转化25.5％.
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