用柠檬酸溶胶-凝胶法制备三效催化剂  

Preparation and character of three-way catalyst by citric acid sol-gel method

作　　者：杨振明[1] 张劲松[1] 曹小明[1] 李峰[1] 徐志军[1] 

机构地区：[1]中国科学院金属研究所

出　　处：《材料研究学报》2003年第4期370-374,共5页Chinese Journal of Materials Research

基　　金：国家九五科技攻关项目

摘　　要：采用柠檬酸溶胶-凝胶法和浸渍法制备出两种具有相同组成的Pt-Rh三效催化剂。在900℃和1200℃的模拟尾气中烧结处理后,溶胶-凝胶法催化剂的50％转化率温度(T_(50))比浸清法催化剂的低30℃左右。对两种催化剂的比较表明,溶胶-凝胶法催化剂具有特殊的网孔状显微结构,能降低贵金属的烧结速度并提高氧化铈的分散度,因而提高了催化剂的抗烧结能力。用柠檬酸溶胶-凝胶法可改善催化剂的热稳定性。Both sintering and catalytic behavior of noble Pt-Rh catalysts, which were prepared by impregnation and sol-gel techniques and aged in a simulated exhaust gas, were investigated. After ageing at 900 ℃and 1200℃, the temperature at which 50% pollutions can be converted (T50) to SG catalyst is 30 ℃ lower than that of IM catalyst. By the comparisons of the specific surface area, XRD and TEM results between the two kinds of three-way catalysts, the sol-gel catalyst shows specific netty microstructure. The netty microstructure of the sol-gel catalyst can increase the disperse state of ceria and decrease the sintering velocity. The thermal stability of the catalyst can be improved by the Sol-gel techniques.

关 键 词：无机非金属材料 三效催化剂 溶胶-凝胶法 柠檬酸 尾气 

分 类 号：TB321[一般工业技术—材料科学与工程]