物理化学学报 >> 2013, Vol. 29 >> Issue (02): 385-390.doi: 10.3866/PKU.WHXB201212031

催化和表面科学 上一篇    下一篇

TiO2负载Mn-Co复合氧化物催化剂上NO催化氧化性能

徐文青1, 赵俊1, 王海蕊1,2, 朱廷钰1, 李鹏1, 荆鹏飞1   

  1. 1 中国科学院过程工程研究所, 湿法冶金清洁生产技术国家工程实验室, 北京 100190;
    2 中国科学院大学, 北京 100049
  • 收稿日期:2012-09-21 修回日期:2012-11-28 发布日期:2013-01-14
  • 通讯作者: 朱廷钰 E-mail:tyzhu@home.ipe.ac.cn
  • 基金资助:

    国家高技术研究发展计划项目(863) (2011AA060802, 2012AA062501, 2012AA062803)资助

Catalytic Oxidation Activity of NO on TiO2-Supported Mn-Co Composite Oxide Catalysts

XU Wen-Qing1, ZHAO Jun1, WANG Hai-Rui1,2, ZHU Ting-Yu1, LI Peng1, JING Peng-Fei1   

  1. 1 National Engineering Laboratory for Hydrometallurgical Cleaner Production Technology, Institute of Process Engineering, Chinese Academy of Sciences, Beijing 100190, P. R. China;
    2 University of Chinese Academy of Sciences, Beijing 100049, P. R. China
  • Received:2012-09-21 Revised:2012-11-28 Published:2013-01-14
  • Supported by:

    The project was supported by the National High Technology Research and Development Program of China (863) (2011AA060802, 2012AA062501, 2012AA062803).

摘要:

氮氧化物(NOx)是大气主要污染物之一, 主要来源于化石燃料的燃烧, 其中NO不溶于水难以去除, 催化氧化技术可以将NO氧化为易溶于水可被脱硫装置去除的NO2, 具有十分重要的实际意义. 本文采用浸渍法制备了不同Mn掺杂量的Mn-Co/TiO2复合金属氧化物催化剂, 考察了其催化NO氧化的活性. 结果表明, Mn的掺杂对Co/TiO2催化剂催化NO氧化的活性有明显促进作用, 掺杂量为6%时, Mn(0.3)-Co(0.7)/TiO2催化剂NO的转化效率最高, 300℃达到88%. 采用X射线衍射(XRD)、N2吸附/脱附、H2程序升温还原(H2-TPR)、O2程序升温脱附(O2-TPD)和原位漫反射傅里叶变换红外(in-situ DRFTIR)光谱等技术对催化剂的物理化学特征进行了表征. 结果发现, 当掺杂量为6%时, Mn一方面促进了催化剂表面活性组分的分散, 增加了催化剂的比表面积和孔径; 另一方面提高了催化剂的还原性能, 促进氧的低温脱附, 此外还促进了反应中间产物桥式NO-3向NO2的反应, 从而提高了Co/TiO2催化剂的NO氧化活性.

关键词: 一氧化氮, 催化氧化, 锰, 钴, 二氧化氮

Abstract:

Globally, NOx is one of the most widespread pollutants. It is generated mainly from the burning of fossil fuels, and NO is very difficult to remove because of its capacity to be dissolved in water. The catalytic oxidation method can be used to convert NO to NO2, which is soluble in water and can be removed using desulfurization devices. Here, a series of TiO2-supported Mn-Co composite oxide catalysts were prepared using the impregnation method. The results of catalytic activity tests showed that the addition of Mn enhanced the efficiency of NO oxidation. Significantly, with 6% doping amounts, Mn (0.3)-Co(0.7)/TiO2 showed the best activity of 88% NO conversion at 300 ° C. X-ray diffraction (XRD), N2 adsorption/desorption, hydrogen temperature-programmed reduction (H2-TPR), oxygen temperatureprogrammed desorption (O2-TPD), and in-situ diffuse reflectance Fourier transform infrared (in-situ DRFTIR) spectroscopy were used to characterize the catalysts. The results indicated that when the doping amount was 6%, the Mn enhanced the specific surface areas and pore volumes, which improved the dispersion of the active component over the TiO2 support. The co-doping of manganese into the Co/TiO2 also enhanced the oxygen desorption capabilities of the catalysts, which improved their reduction abilities. In addition, bridge NO3-, the key intermediate, was converted into NO2; this conversion was also enhanced by the presence of Mn on the Co/TiO2 catalyst. All of the above reasons account for the high NO catalytic oxidation activity of the supported Mn-Co composite oxide catalysts.

Key words: Nitric oxide, Catalytic oxidation, Manganese, Cobalt, Nitrogen dioxide

MSC2000: 

  • O643