高等学校化学学报 ›› 2014, Vol. 35 ›› Issue (1): 92.doi: 10.7503/cjcu20130808

• 物理化学 • 上一篇    下一篇

铌改性的Pd/Al2O3催化剂催化苯燃烧反应

贺站锋1,2, 王丹1,2, 刘涛1,2, 王奂祎1,2, 蒋毅1()   

  1. 1. 中国科学院成都有机化学研究所, 成都 610041
    2. 中国科学院大学, 北京 100049
  • 收稿日期:2013-08-20 出版日期:2014-01-10 发布日期:2013-12-04
  • 作者简介:联系人简介: 蒋 毅, 男, 博士, 研究员, 博士生导师, 主要从事催化化学及催化新工艺的研究. E-mail:yjiang@cioc.ac.cn
  • 基金资助:
    国家自然科学基金(批准号: 21172024)资助

Nb-modified Pd/Al2O3 Catalysts for Benzene Catalytic Combustion

HE Zhanfeng1,2, WANG Dan1,2, LIU Tao1,2, WANG Huanyi1,2, JIANG Yi1,*()   

  1. 1. Chengdu Institute of Organic Chemistry, Chinese Academy of Sciences, Chengdu 610041, China
    2. University of Chinese Academy of Sciences, Beijing 100049, China
  • Received:2013-08-20 Online:2014-01-10 Published:2013-12-04
  • Contact: JIANG Yi E-mail:yjiang@cioc.ac.cn
  • Supported by:
    † Supported by the National Natural Science Foundation of China(No.21172024)

摘要:

采用浸渍法制备了Nb改性的Pd/Al2O3催化剂, 考察了该催化剂催化苯燃烧反应性能, 并研究了催化剂的稳定性. 结果表明, Nb的添加明显提高了Pd/Al2O3催化剂性能, 在195 ℃时苯转化率达到90%, 苯的完全燃烧温度降低了40 ℃. 采用X射线衍射(XRD)、 X射线光电子能谱(XPS)、 透射电子显微镜(TEM)、 H2 程序升温还原(H2-TPR)、 NH3程序升温脱附(NH3-TPD)和氮气吸附等手段对催化剂进行了表征, 结果表明, Nb的加入不仅提高了Pd物种的分散度, 同时改变了部分Pd的价态, 形成适宜反应的PdO-Pd物种, 并促进了催化剂表面氧浓度的增加, 使氧物种氧化能力增强, 从而提高了催化性能. 1%Pd-5%Nb/Al2O3催化剂的催化活性高于2.0%Pd/Al2O3催化剂.

关键词: 钯铌催化剂, 氧化铌, 苯, 催化燃烧

Abstract:

Pd/Al2O3 catalyst modified by Nb promoter was prepared and tested for benzene catalytic combustion. The catalysts were characterized by X-ray diffraction, X-ray photoelectron spectroscopy, temperature-programmed desorption of NH3, H2 temperature-programmed reduction, and N2 adsorption. The results showed that the addition of Nb effectively improved the activity and stability of Pd/Al2O3 catalyst by increasing the dispersion of Pd active components, changing the oxidation state of partial palladium and increasing oxygen species concentration on the surface of catalyst. In case of Pd-Nb/Al2O3 catalyst, the benzene conversion of 90%was obtained at temperature as low as 195 ℃. Moreover, the 1%Pd-5%Nb/Al2O3 catalyst was more active than the 2%Pd/Al2O3 catalyst. It is concluded that Pd and Nb have a synergistic effect in benzene catalytic combustion.

Key words: Palladium niobium catalyst, Niobium oxide, Benzene, Catalytic combustion

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