Pd/Ce_(0.5)Zr_(0.5)O_2三效催化剂负载方法  

Preparation Method of Pd/Ce_(0.5)Zr_(0.5)O_2 Three-Way Catalysts

作　　者：朱保伟[1] 陈宏德[1] 田群[1] 房师平[1] 

机构地区：[1]中国科学院生态环境研究中心,北京100085

出　　处：《环境科学》2004年第6期21-25,共5页Environmental Science

基　　金：国家高技术研究发展计划 ( 863计划 )项目( 2 0 0 1AA64 3 0 40 0 2 )

摘　　要：分别采用沉积沉淀、直接混合和传统的浸渍法制备 1%Pd/Ce0 5Zr0 5O2 催化剂 ,研究了Pd负载方法对催化剂活性影响 .运用H2 TPR和原位漫反射红外 (DRIFTS)研究了Pd 铈锆载体间的相互作用及Pd/Ce0 5Zr0 5O2 催化剂上的三效反应机理 .结果表明沉积沉淀法制备的Pd/Ce0 5Zr0 5O2 催化剂 (Pd DP)表现出最强的Pd 载体作用及最优活性 ,原位红外实验发现Pd DP上存在与传统的浸渍法制备的Pd IMP催化剂不同的NO催化还原途径 ,推测Pd 载体间相互作用引起NO还原机理差异 。Pd/Ce 0.5Zr 0.5O 2 (CZ) catalysts were prepared by deposition-precipitation (DP), mixing (MIX) and conventional impregnation (IMP) methods, and the effects of the preparation methods on the three-way catalytic behaviors were investigated. Hydrogen temperature-programmed reduction (H 2-TPR) and in situ diffuse reflectance infrared fourier transform spectroscopy (DRIFTS) were performed to understand the Pd-support interaction and the three-way catalytic reaction mechanisms. The experiments results reveal that the catalyst prepared by deposition-precipitation (DP) method shows the strongest Pd-support interaction and the best light-off performance. In situ DRIFTS results suggest that there exists alternative route of NO x reduction over Pd-DP catalyst. And it is supposed that Pd-support interaction leads to the difference of reaction mechanism and then the diversity of light-off performances.

关 键 词：三效催化剂 沉积沉淀法 Pd-载体 NOx吸附 负载方法 

分 类 号：X511[环境科学与工程—环境工程] X703.5