摘要
用浸渍法制备了不同比例的CeO2 ZrO2 复合氧化物 ,并用XRD ,H2 TPR和BET等研究了复合氧化物的晶相、还原性能及热稳定性 .结果表明 ,所制备的CeO2 ZrO2 复合氧化物形成了固溶体 ,Ce0 6Zr0 4O2 比Ce0 90 Zr0 10 O2 更容易被H2 还原 ;110 0℃老化后 ,晶胞参数无明显变化 ,比表面积仍有 11 8m2 /g .模拟二冲程摩托车尾气组成 ,对用贵金属Pt,Pd ,Rh与CeO2及CeO2 ZrO2 固溶体所制备的催化剂进行了活性评价 .结果显示 ,110 0℃老化后 ,催化剂仍具有很高的氧化活性 .在贫氧区 ,Pt Pd Rh/Ce0 6Zr0 4O2 Al2 O3 对碳氢化合物氧化的催化活性则有一定的优势 ,是一种具有较高热稳定性的催化剂 .
In this paper, the CeO2-ZrO2 composite oxide with different composition was prepared by dip-coating method. Meanwhile, the crystalline phase structure, reduction performance, surface area and thermostability of the oxide were characterized by using XRD, H-2-TPR and BET. The results showed that the solid solution was formed in the CeO2-ZrO2 composite oxide, and Ce0.6MZr0.4O2 was more easily to be reduced by H-2, compared with Ce0.90Zr0.10O2, the parameters of its crystal cells were not obviously changed, and the surface area was still as high as 11.8 m(2)/g when calcined at 1100 degreesC for 4 h. The catalytic activity of Pt-Pd-Rh/CeO2-Al2O3 and Pt-Pd-Rh/CeO2-ZrO2-Al2O3 was investigated by using simulating emission gas of 2-stroke motorcycle, and the results revealed that the calcined catalysts still have high activity. In the lean oxygen area, the Pt-Pd-Rh/Ce0.6Zr0.4O2-Al2O3 catalyst, which has superiority of activity for hydrocarbon oxidation, over other two catalysts, is a good catalyst with high thermostability.
出处
《催化学报》
SCIE
CAS
CSCD
北大核心
2002年第4期341-344,共4页
基金
国家自然科学基金资助项目 ( 2 0 176 0 5 7)