三效催化剂中促进剂氧化铈的作用研究进展

Review of Ceria as Promoters in Three-way Catalysis

综述了CeO_2在三效催化剂中的应用研究现状。包括在贫燃和富燃条件下起储存和释放氧的作用;促进贵金属的分散和增加Al_2O_3载体的稳定性;促进水煤气转化和水蒸气重整反应;在金属载体界面上增加催化反应活性位并促使CO在晶格氧上有效氧化以及催化去除SO_x气体。

This paper reviews and discusses the multiple roles of CeO_2 in threeway catalysis.The major role of ceria as promoters would be that of improved activity and selectivity,and ~increased thermal stability of catalytic materials.Ceria performs the following functions in ~three way catalysts:store and release oxygen under respective,lean and rich conditions;promote ~noble metal dispersion and increase the thermal stability of Al_2O_3;promote the water gas shift and steam reforming reactions;favour catalytic activity at interfacial metalsupport sites and ~promote CO removal through oxidation at lattice oxygen;and catalyze SO_x removal.