物理化学学报 >> 2013, Vol. 29 >> Issue (01): 176-182.doi: 10.3866/PKU.WHXB201210094

催化和表面科学 上一篇    下一篇

MnOx/Al-SBA-15的结构性质及低温NH3选择性催化还原NOx

黄萍1, 盘思伟2, 黄碧纯1,3, 程华1, 叶代启1,3, 吴军良1,3, 付名利1,3, 卢圣良4   

  1. 1 华南理工大学环境科学与工程学院, 广州 510006;
    2 广东电网公司电力科学研究院, 广州 510080;
    3 广东省大气环境与污染控制重点实验室, 广州 510006;
    4 广州环保投资有限公司, 广州 510700
  • 收稿日期:2012-08-13 修回日期:2012-10-08 发布日期:2012-12-14
  • 通讯作者: 黄碧纯 E-mail:cebhuang@scut.edu.cn
  • 基金资助:

    广州市重大科技专项计划(X2DLB2080501)资助项目

Structural Properties of MnOx/Al-SBA-15 in Low-Temperature Selective Catalytic Reduction of NOx with NH3

HUANG Ping1, PAN Si-Wei2, HUANG Bi-Chun1,3, CHENG Hua1, YE Dai-Qi1,3, WU Jun-Liang1,3, FU Ming-Li1,3, LU Sheng-Liang4   

  1. 1 College of Environmental Science & Engineering, South China University of Technology, Guangzhou 510006, P. R. China;
    2 Electric Power Research Institute of Guangdong Power Grid Corporation, P. R. China;
    3 Guangdong Provincial Key Laboratory of Atmospheric Environment and Pollution Control, Guangzhou 510006, P. R. China;
    4 Guangzhou Environment Protection Investment Co. Ltd., Guangzhou 510700, P. R. China
  • Received:2012-08-13 Revised:2012-10-08 Published:2012-12-14
  • Supported by:

    The project was supported by the Significant Technology Special Plan Project of Guangzhou, China (X2DLB2080501).

摘要:

采用后合成法制备MnOx/Al-SBA-15催化剂, 考察了催化剂的低温NH3选择性催化还原(SCR)NOx的性能. 利用傅里叶透射红外变换(FTIR)光谱、N2吸附-脱附、X射线衍射(XRD)、扫描电镜(SEM)、拉曼光谱(Raman)、X射线光电子能谱(XPS)及NH3程序升温脱附(NH3-TPD)的表征手段, 对催化剂的结构性质和SCR性能进行了系统分析. 结果表明, 适量Al的掺杂能提高MnOx/SBA-15催化剂的SCR活性, 当硅铝摩尔比为50时, 催化剂活性最佳. 表征结果显示, Al掺杂后, 催化剂仍保持良好的骨架结构, 较大比表面、孔容和孔径, 并且Mn在催化剂表面富集, 由低价态转化为高价态, MnO2为催化剂的主要活性相. 此外, Al的掺杂使MnOx在催化剂表面高度分散, 表面酸性增强, 从而提高了催化剂的SCR活性.

关键词: 乙酰丙酮锰, 铝, SBA-15, 高分散性, 表面酸性, 选择性催化还原

Abstract:

A series of MnOx/Al-SBA-15 catalysts were prepared by post synthesis methods for lowtemperature selective catalytic reduction (SCR) of NOx with NH3. Structural properties and catalytic performance were comprehensively characterized by Fourier transform infrared (FTIR) spectroscopy, N2 adsorption-desorption, X-ray powder diffraction (XRD), scanning electron microscopy (SEM), Raman spectroscopy, X-ray photoelectron spectroscopy (XPS), and temperature programmed desorption of NH3 (NH3-TPD). The results showed that moderate addition of Al improved the SCR activity of the MnOx/SBA-15 catalyst, and the MnOx/Al-SBA-15 catalyst with nSi/nAl=50 had the highest activity. Characterization results revealed that the doped material MnOx/Al-SBA-15 catalysts maintained high specific surface area, large pore volume, and uniform pore size. Al doping improved the concentration and valence state of Mn, where MnO2 was determined to be the main active phase. Owing to a high dispersion of MnOx and a stronger surface acidity, the MnOx/Al(50)-SBA-15 catalyst exhibited higher SCR activity.

Key words: Acetyl acetone manganese, Aluminum, SBA-15, High dispersion, Surface acidity, Selective catalytic reduction

MSC2000: 

  • O643