铈锆复合氧化物制备及甲烷燃烧催化活性表征  

Cerium zirconium mixed oxides preparation and its methane catalytic combustion

作　　者：龙志奇[1] 崔梅生[1] 彭新林[1] 张顺利[1] 黄小卫[1] 

机构地区：[1]北京有色金属研究总院有研稀土新材料股份有限公司,北京100088

出　　处：《中国有色金属学报》2006年第6期1076-1080,共5页The Chinese Journal of Nonferrous Metals

摘　　要：采用共沉淀水热联合法制备了大比表面铈锆复合氧化物材料,在较低焙烧温度400℃下形成了稳定的晶相结构,500℃焙烧新鲜比表面达135.44 m2/g,900℃、6 h老化后比表面仍维持44.07 m2/g。采用沉淀陈化工艺,并掺杂改性,得到的铈锆复合氧化物,稳定性更高,经950℃、2 h老化后,最高比表面可达59.62 m2/g。活性氧化铝与铈锆复合氧化物有协同作用,二者复合得到了更高性能的氧化物材料,新鲜比表面为188.92 m2/g,经950℃、4 h老化后,比表面为71.64 m2/g,经1 050℃、4 h老化后,比表面为58.10 m2/g。对所得铈锆材料进行了X射线衍射、吸脱附表征,并负载钯贵金属制得催化材料,以甲烷完全催化燃烧为探针反应,研究了铈锆复合氧化物材料的甲烷燃烧催化性质。结果表明,铈锆复合氧化物材料是很好的燃烧催化剂二载材料,负载钯催化剂具有较高催化活性,起燃温度降低至352℃。The cerium zirconium mixed oxides with high performance such as high surface area, good thermal stability were prepared by the method of co-precipitation and hydrothermal treatment. The stable crystal phase was formed under low temperature of 400℃, the surface area of fresh sample calcined at 500℃ is up to 135.44 m^2/g, and the surface area of aged sample calcined at 900℃ for 6 h is 44.07 m^2/g. The more thermal stable cerium zirconium mixed oxide powders were obtained by the process of co-deposition and hot aging, and by the technology of AP＋ doping modification, whose highest surface area of aged samples at 950℃for 2 h is up to 59.62 m^2/g. The superior mixed oxide is formed with the active alumina introduction into cerium zirconium mixed oxides, whose fresh surface area is 188.92 m^2/g, aged sample at 950℃ for 4 h is 71.64 m^2/g, and aged sample at 1 050℃ for 4 h is 58.10 m^2/ g. The mixed oxides was characterized by means of X-ray diffraction, adsorption and de-sorption. The cerium zirconium catalyst was obtained by palladium metal impregnation techniques. With methane catalytic combustion as probe reaction, the catalytic activity of cerium zirconium mixed oxides was studied, and the results show that cerium zirco- nium mixed oxides is a good carrier of support for combustion catalysts. The catalytic activity of palladium suppor- ted cerium zirconium catalyst is high, whose light-off temperature is as low as 352℃.

关 键 词：铈锆复合氧化物 高比表面 高温稳定性 甲烷催化燃烧 

分 类 号：O643[理学—物理化学]