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在共沉淀法的基础上辅助以超声制备了铈锆铝复合氧化物(CZA),采用比表面分析仪、X射线衍射、程序升温还原、储氧量和X射线光电子能谱对材料进行了表征.结果表明,超声振荡有助于小而均匀的孔生成,有利于Pd物种的分散;超声振荡还能提高CZA的储氧量,使材料的表面组成与体相组成趋于一致.催化活性测试表明,材料经过超声处理的Pd-CZA净化乙醇汽油车尾气时,可以将氧气的完全利用窗口从0~0.64%拓宽至0~1.16%;并且使乙醇、C3H8和CO起燃温度分别下降了30,28和24℃.此外,Pd物种与CZA-U的相互作用有利于NO与C3H8和C2H5OH的反应.
Based on the coprecipitation method, cerium-zirconium-aluminum composite oxide (CZA) was prepared by ultrasonic method. The surface area of the composite was characterized by means of surface area analyzer, X-ray diffraction, temperature programmed reduction, oxygen storage capacity and X-ray photoelectron spectroscopy The results show that the ultrasonic oscillation can help to generate small and uniform pores, which is conducive to the dispersion of Pd species. Ultrasonic oscillation can also increase the oxygen storage capacity of CZA and make the surface composition and bulk composition of the material consistent. The results show that when the material is sonicated Pd-CZA to purify the ethanol gasoline vehicle exhaust, the window of full utilization of oxygen can be widened from 0% to 0.64% to 0% to 1.16%, and the light-off temperatures of ethanol, C3H8 and CO decrease by 30% , 28 and 24 ° C. In addition, the interaction of Pd species with CZA-U favors the reaction of NO with C3H8 and C2H5OH.