三效催化剂用储氧材料铈锆氧化物固溶体的制备

Preparation of Ceria-Zirconia Solid Solution in Three-way Catalysts

铈锆氧化物固溶体由于具有优良的储氧、释放氧的功能而在汽车尾气三效催化剂中得到广泛应用。制备铈锆氧化物固溶体的方法主要有共沉淀法、反相微乳法和溶胶-凝胶法(sol-gel)。共沉淀法工艺简单,易操作,便于大规模实施;反相微乳法以微乳液作为反应介质,可以很好的控制粒子的半径,制备纳米固溶体;采用溶胶-凝胶法能制备出高纯度的固溶体。另外,还有一些其他制备方法。不同方法各有优缺点,对所得固溶体的纯度、比表面积、晶粒度、氧化还原能力都有影响。

Due to the excellent ability of ceria-zirconia solid solution to act as an oxygen store by storing/releasing O2,it＇s been used widely in three-way catalyst.The main methods of preparing the solid solution are co-precipitation,reversed microemulsion method and sol-gel.The co-precipitation method is easy to carry out,so it＇s suitable to be applied in the industry.While the reversed micro-emulsion method is used,reversed micelles are created as reactors to obtain ultrafine and monodispersed nanoparticles.The ceria-zirconia solid solution of high purity can be obtained through sol-gel method.Besides,there＇re other ways to prepare the solid solution.However,each method has its own advantages and disadvantages,and the properties of the ceria-zirconia solid solution,such as chemical,physical characteristics and catalytic performance,etc.are determined by the preparation methods.