物理化学学报 >> 2007, Vol. 23 >> Issue (01): 73-78.doi: 10.1016/S1872-1508(07)60007-2

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Ce0.35Zr0.55La0.10O1.95对低贵金属Pt-Rh型三效催化剂性能的影响

郭家秀;袁书华;龚茂初;张磊;吴冬冬;赵明;陈耀强   

  1. 四川大学化学学院, 成都 610064
  • 收稿日期:2006-07-18 修回日期:2006-09-05 发布日期:2007-01-08
  • 通讯作者: 陈耀强 E-mail:yqchen@email.scu.edu.cn

Influence of Ce0.35Zr0.55La0.10O1.95 Solid Solution on the Performance of Pt-Rh Three-way Catalysts

GUO Jia-Xiu;YUAN Shu-Hua;GONG Mao-Chu;ZHANG Lei;WU Dong-Dong;ZHAO Ming;CHEN Yao-Qiang   

  1. College of Chemistry, Sichuan University, Chengdu 610064, P. R. China
  • Received:2006-07-18 Revised:2006-09-05 Published:2007-01-08
  • Contact: CHEN Yao-Qiang E-mail:yqchen@email.scu.edu.cn

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摘要： 采用共沉淀技术制备了Ce0.35Zr0.55La0.10O1.95固溶体, 其织构和结构性能以及氧化还原性能分别采用BET、XRD和程序升温(TP)技术进行了表征. 制备了低贵金属Pt-Rh型三效催化剂, 考察了Ce0.35Zr0.55La0.10O1.95对催化剂性能的影响. XRD和BET的结果表明, 经600 ℃焙烧5 h后, Ce0.35Zr0.55La0.10O1.95具有与Ce0.50Zr0.50O2相似的立方结构和高的比表面积；经1000 ℃焙烧5 h后, 仍能保持稳定的立方结构和47.25 m2•g−1的比表面积, 表现出优越的织构性能和高的热稳定性. H2-TPR和O2-TPO的结果表明, Ce0.35Zr0.55La0.10O1.95具有比Ce0.50Zr0.50O2更好的氧化还原性能. 和含Ce0.50Zr0.50O2的催化剂相比, 含Ce0.35Zr0.55La0.10O1.95的催化剂具有较宽的工作窗口, 优越的低温起燃性能, 较强的水气变换能力；催化剂经1000 ℃高温水热老化5 h后, 仍具有良好的催化活性, 表现出了优异的抗老化性能.

关键词: 低贵金属, 三效催化剂, 程序升温, 氧化还原

Abstract: Ce0.35Zr0.55La0.10O1.95 solid solution was prepared by coprecipitation technique and characterized by specific surface area measurements (BET), X-ray diffraction (XRD), and temperature-programmed (TP) technique. Ce0.35Zr0.55La0.10O1.95 was used to prepare low Pt-Rh three-way catalyst (TWC) and its influence on the performance of TWC was investigated. The results showed that Ce0.35Zr0.55La0.10O1.95 had a cubic structure similar to Ce0.50Zr0.50O2 and high specific area after calcined at 600 ℃ for 5 h. Furthermore, after being aged at 1000 ℃ for 5 h, Ce0.35Zr0.55La0.10O1.95 still maintained a stable cubic structure and a specific surface area of 47.25 m2•g−1. The results of H2-TPR and O2-TPO indicated that Ce0.35Zr0.55La0.10O1.95 had good redox properties. The catalyst containing Ce0.35Zr0.55La0.10O1.95 possessed fairly wide range of three-way working-windows, good low temperature light-off properties, and better ability of water-gas shift. Being hydrothermal aged at 1000 ℃, the catalyst containing Ce0.35Zr0.55La0.10O1.95 still showed good catalytic activity in comparison with Ce0.50Zr0.50O2 TWC, which indicated that Ce0.35Zr0.55La0.10O1.95 improved the anti-aging properties of the catalyst.

Key words: Low precious metal, Three-way catalyst, Temperature-programmed technique, Redoxidation