Acta Phys. -Chim. Sin. ›› 2016, Vol. 32 ›› Issue (7): 1734-1746.doi: 10.3866/PKU.WHXB201603235

• ARTICLE • Previous Articles     Next Articles

Preparation of CeO2-ZrO2-Al2O3 with a Composite Precipitant and Its Supported Pd-Only Three-Way Catalyst

Hong-Mei LI1,2,3,Li LAN1,2,*(),Shan-Hu CHEN4,Da-Yu LIU1,Wei WANG1,Mao-Chu GONG2,Yao-Qiang CHEN2,*()   

  1. 1 Faculty of Pharmacy and Bioengineering, Chengdu University, Chengdu 610106, P. R. China
    2 Key Laboratory of Green Chemistry & Technology, Ministry of Education, College of Chemistry, Sichuan University, Chengdu 610064, P. R. China
    3 Key Laboratory of Green Chemistry, Sichuan University of Science and Engineering, Zigong 643000, Sichuan Province, P. R. China
    4 4Sinocat Environmental Protection Co., Ltd., Chengdu 611731, P. R. China
  • Received:2016-01-18 Published:2016-07-08
  • Contact: Li LAN,Yao-Qiang CHEN E-mail:wskadlb@163.com;chenyaoqiang@scu.edu.cn
  • Supported by:
    the National Natural Science Foundation of China(21173153);National Hi-tech Research and Development Program of China (863)(2015AA034603);Opening Project of Key Laboratory of Green Chemistry of Sichuan Institutes of Higher Education, China(LYJ1407)

Abstract:

Acomposite precipitant composed of ammonia and ammoniumcarbonate was used to prepare CeO2-ZrO2-Al2O3 (CZA). For comparison, two other CZA samples were prepared using ammonia and ammonium carbonate as the precipitants, respectively. Differences in the textural, structural and redox properties, together with the evolution upon thermal aging treatment and the catalytic performance of the corresponding Pd-only three-way catalysts, were investigated systematically. The choice of precipitant was found to affect the interactions between CeO2-ZrO2 (CZ) and Al2O3. When ammonia was used as the precipitant, the resulting CZ and Al2O3 seemed insusceptible to each other, thus the obtained CZA composite displayed inferior thermal stability due to the weakest interaction between CZ and Al2O3. In the case of ammonium carbonate, stronger interaction between CZ and Al2O3 enhanced the thermal stability of CZA, but in the meantime, the homogeneity of the CZ solid solution was severely impaired by Al2O3, leading to undesirable redox performance. Fortunately, the use of the composite precipitant brought about favorable interaction between CZ and Al2O3, leading to excellent textural and structural properties along with the highest thermal stability of the CZA compound. Consequently, the corresponding Pd-based catalyst displayed prominent reducibility and oxygen storage capacity (OSC) performance, as well as superior three-way catalytic performance.

Key words: CeO2-ZrO2-Al2O3 compound, Composite precipitant, Pd-only three-way catalyst, Interaction, Thermal stability

MSC2000: 

  • O643