催化学报

催化学报 ›› 2007, Vol. 28 ›› Issue (5): 463-468.

• 研究论文 • 上一篇    下一篇

掺Ag对氧化锰八面体分子筛催化CO氧化性能的影响

胡蓉蓉1,程易1,谢兰英2,王德峥1   

  1. 1 清华大学化学工程系北京市绿色反应工程与工艺重点实验室, 北京 100084; 2 湖南中烟工业公司技术中心, 湖南长沙 410001
  • 收稿日期:2007-05-25 出版日期:2007-05-25 发布日期:2011-04-28

Effect of Doped Ag on Performance of Manganese Oxide Octahedral Molecular Sieve for CO Oxidation

HU Rongrong1, CHENG Yi1, XIE Lanying2, WANG Dezheng1*   

  1. 1 Department of Chemical Engineering, Beijing Key Laboratory of Green Chemical Reaction Engineering and Technology, Tsinghua University, Beijing 100084, China; 2 Technology Center of China Tobacco Hunan Industrial Corporation, Changsha 410001, Hunan, China
  • Received:2007-05-25 Online:2007-05-25 Published:2011-04-28

PDF

1094

被引次数

74

摘要： 采用回流法在酸性介质中合成了掺杂贵金属Ag的氧化锰八面体分子筛(OMS-2). 利用X射线衍射、低温N2吸附、透射电子显微镜及程序升温脱附(TPD)等技术对固体材料的结构进行了表征,考察了材料对CO氧化反应的催化性能,以及Ag的掺杂对该反应的影响. 结果表明,合成的OMS-2材料属于cryptomelane一维隧道结构,适量Ag的掺杂使分子筛的有序性得到改善,孔径更均一. Ag的加入还能明显提高催化剂的反应活性. O2-TPD和CO-TPD实验表明, Ag的引入使材料对CO的吸附性能及晶格氧的扩散能力得到显著增强,这是提高催化剂对CO氧化催化能力的主要原因.

关键词: 氧化锰, 八面体分子筛, 银, 一氧化碳, 氧化

Abstract: A series of Ag-doped manganese oxide octahedral molecular sieves (OMS-2) were synthesized by the reflux method in an acid medium. The structure of the catalysts was characterized by X-ray diffraction, N2 adsorption, transmission electron microscopy, and temperature-programmed desorption (TPD). The effect of the promoter Ag was deduced. The results showed that the catalysts have the typical cryptomelane structure with a one-dimensional channel. The doping with Ag resulted in Ag/OMS-2 catalysts with a higher specific surface area and narrower pore size distribution than OMS-2. The catalysts showed excellent catalytic activity for CO oxidation and the catalytic activity was increased after Ag introduction. O2-TPD and CO-TPD results showed that this was because the doping with Ag increased the rate of CO adsorption and the diffusion of lattice oxygen ions.

Key words: manganese oxide, octahedral molecular sieve, silver, carbon monoxide, oxidation