铈锆固溶物载Pd催化剂的构造特征及其活性

以共沉淀法和滤纸作为模板剂的模板法制备铈锆固溶物(Ce／Zr=1)负载Pd催化剂，用XRD对其进行晶相分析，两种方法均形成立方萤石结构．TPR实验揭示了滤纸模板法制备的铈锆固溶物高温老化催化剂更易被还原．催化剂表面Pd的分散度和活性评价实验表明，催化剂表面贵金属的分散度在一定程度上决定催化剂的活性，载体物性影响Pd的分散度，滤纸模板法制备的铈锆固溶物负载Pd催化剂有较高的Pd分散度，表现出比共沉淀法制备的铈锆固溶物负载Pd催化剂好的三效活性．

COMPARISON OF Pd CATALYSTS SUPPORTED OVER CeO2-ZrO2 SOLID SOLUTION PREPARED:DIFFERENCES IN TEXTURAL CHARACTERIZATION AND ACTIVITY

CeO 2-ZrO 2 solid solutions(Ce/Zr=1)prepared by co-precipitation and templating approach(filter paper is used as templating material),were used as supports for Pd catalysts.Catalyst structures have been characterized by means of X-ray diffraction(XRD),CeO 2-ZrO 2 solid solution prepared by two methods are proved to be a cubic fluorite-type phase.Temperature programmed reduction(TPR)experiments have found CeO 2-ZrO 2 solid solution prepared by templating approach much easier to be reduced.Pd dispersion on the surface of catalysts and activity tests indicated that catalytic performance was determined by Pd dispersion to a certain extent,while Pd dispersion is affected by characterization of the support,Pd catalyst supported on CeO 2-ZrO 2 solid solution prepared by templating approach had larger dispersion of Pd,which represented much better performance than the other one.