Acta Phys. -Chim. Sin. ›› 2010, Vol. 26 ›› Issue (11): 3009-3016.doi: 10.3866/PKU.WHXB20101120

• CATALYSIS AND SURFACE STRUCTURE • Previous Articles     Next Articles

Deactivation of MnOx-CeOx/ACF Catalysts for Low-Temperature NH3-SCR in the Presence of SO2

SHEN Bo-Xiong, LIU Ting   

  1. College of Environmental Science and Engineering, Nankai University, Tianjin 300071, P. R. China
  • Received:2010-04-12 Revised:2010-08-02 Published:2010-10-29
  • Contact: SHEN Bo-Xiong E-mail:shenbx@nankai.edu.cn
  • Supported by:

    The project was supported by the National Natural Science Foundation of China (0976050), Programfor NewCentury Excellent Talents in University, China (07-0457) and National Key Technology Research and Development Programof Tianjin, China (09ZCKFSH01900).

Abstract:

The low-temperature selective catalytic reduction of NO with NH3 (NH3-SCR) over MnOx-CeOx/ACF (activated carbon fiber) modified by Fe, Cu, or V was investigated in the presence of SO2. The results revealed that the SO2 tolerance of MnOx-CeOx/ACF was not enhanced after Cu and V modification. The addition of Fe to MnOx-CeOx/ ACF enhanced its resistance to SO2 poisoning over the first 6 h in the presence of SO2, but then deactivated quickly. The samples were analyzed by N2 adsorption, X-ray photoelectron spectroscopy (XPS), Fourier transform infrared (FT- IR) spectroscopy, and thermogravimetric analysis (TGA).We found that catalyst surface coverage by ammoniumsalts as well asmetallic sulfates and sulfites formed by the reaction between SO2 and metal oxides in the catalysts was responsible for catalyst deactivation in the presence of SO2. Sulfur on the surface of the deactivated catalysts was mainly in the form of metallic sulfates and sulfites with 70.4%, 68.9%, 86.3%, and 71.4%(w) on deactivated MnOx-CeOx/ACF, Fe- MnOx-CeOx/ACF, Cu-MnOx-CeOx/ACF, and V-MnOx-CeOx/ACF, respectively. A valuable contribution towards understanding the deactivation of catalysts based on MnOx-CeOx/ACF for the SCR in the presence of SO2 was made.

 

Key words: Low-temperature selective catalytic reduction, MnOx-CeOx/ACF, NO, SO2

MSC2000: 

  • O643