The Surface Adsorption and Selective Catalytic Reaction of NO on Cu-ZSM-5 Using In situ DRIFTS
ZHANG Ping1,WANG Le-fu2,CHEN Yong-heng1
1. Department of Environmental Science, Guangzhou University, Guangzhou 510006, China 2. Department of Chemical Engineering, South China University of Technology, Guangzhou 510640, China
Abstract：The prepared Cu-ZSM-5 catalyst presents higher activity at low temperature during the selective catalytic reduction (SCR) of NO, and the conversion from NO to N2 is 70.6% at 613 K. The in situ diffuse reflectance FTIR spectroscopy (in situ DRIFTS) is an important method for studying surface adsorption of catalyst and mechanism of catalytic reaction, and was used to study the surface adsorbed species and the selective catalytic reduction reaction of NO on Cu-ZSM-5 catalyst in the presence of propene as reductant, with excess O2 and at 298-773 K. Based on the in-situ DRIFTS, a reaction mechanism is proposed that on Cu-ZSM-5, NO is first transformed to a series of NOx surface adsorbates, then these species react with the activating species of propene (CxHy or CxHyOz) to form organo-intermediates, including a process from organo-NH to organo-CN again to organo-NOx (organo-nitro or organo-nitrito), and finally these key intermediates react to form nitrogen. The role of Cu is to promote NOx content. Propene is easily activated on Cu-ZSM-5 with oxygen, and furthermore, the presence of oxygen is necessary to form organo-NOx intermediates.
张平1,王乐夫2,陈永亨1. In situ DRIFTS研究NO在Cu-ZSM-5上的表面吸附及选择性催化还原[J]. 光谱学与光谱分析, 2007, 27(06): 1102-1105.
ZHANG Ping1,WANG Le-fu2,CHEN Yong-heng1. The Surface Adsorption and Selective Catalytic Reaction of NO on Cu-ZSM-5 Using In situ DRIFTS. SPECTROSCOPY AND SPECTRAL ANALYSIS, 2007, 27(06): 1102-1105.
