高等学校化学学报

高等学校化学学报 ›› 2001, Vol. 22 ›› Issue (11): 1873.

• 研究论文 • 上一篇    下一篇

沉淀剂对Au/ZnO催化剂上CO氧化性能及催化剂结构的影响

王桂英, 廉红蕾, 徐跃, 张文祥, 蒋大振, 吴通好   

  1. 吉林大学化学系, 长春 130023
  • 收稿日期:2000-10-08 出版日期:2001-11-24 发布日期:2001-11-24
  • 通讯作者: 封继康(1939年出生),男,教授,博士生导师,从事量子化学研究.E-mail:fenjikan@public.cc.j.lcn E-mail:fenjikan@public.cc.jl.cn
  • 基金资助:

    太原煤转化国家重点实验室;吉林大学创新基金;国家自然科学基金(批准号:20073167)资助

Effect of Precipitant on the Performances and Structures of Au/ZnO Catalysts for CO Oxidation

WANG Gui-Ying, LIAN Hong-Lei, XU Yue, ZHANG Wen-Xiang, JIANG Da-Zhen, WU Tong-Hao   

  1. Department of Chemistry, Jilin University, Changchun130023, China
  • Received:2000-10-08 Online:2001-11-24 Published:2001-11-24

PDF (PC)

被引次数

31

摘要： 在25℃和进料中含水条件下,考察了由Na2CO3,(NH4)2CO3,NaOH和NH4OH等4种沉淀剂制备的Au/ZnO催化剂上CO氧化活性和稳定性.结果表明,沉淀剂影响Au/ZnO催化剂的前体组成、金粒子和ZnO粒子大小、比表面积及CO氧化性能.由NH4OH制备的Au/ZnO催化剂活性和稳定性较差,CO转化率只有15%;由其它3种沉淀剂制备的Au/ZnO催化剂的CO氧化活性和稳定性明显改善,可至少连续反应1100h,且保持CO完全氧化,其中Na2CO3是最佳沉淀剂.在反应过程中反应气氛可引起金粒子的聚集及在催化剂表面生成新的碱式碳酸锌物相.催化剂的稳定性与金粒子长大速度和碳酸根累积量有关.

关键词: Au/ZnO, 沉淀剂, CO氧化, 活性, 稳定性

Abstract: Various Au/ZnOcatalysts were prepared by a coprecipitation method with four kinds of precipitants, Na2CO3, (NH4)2CO3, NaOHand NH4OH, and the catalytic performance of COoxidation at an ambient temperature and humidity were studied. It was found that the precipitants play an important role for the Au/ZnOcatalyst structure, such as the precursors, the particle size of ZnOand metallic gold and the BETsurface area of Au/Zn Ocatalysts. The sample prepared by using NH4OHas precipitant exhibited a lower activity and poorer stability, while the Au/ZnOcatalysts prepared by other three precipitants can maintain COcompletely oxidized to CO2 for at least1100 h. The feed gas mixture can result in sintering of metallic gold and accumulation of carbonate like species on the surface of Au/ZnOcatalysts during the CO-oxidation process. The stability is related to the rate of gold sintering and the amount of hydrozincite formed on the catalyst surface.

Key words: Au/ZnO, Precipitant, CO oxidation, Activity, Stability

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