Pt/MOx (M = Al, Ce, Fe, Cr-Fe, Co-Fe)催化剂上丙烷催化燃烧反应中水汽的作用机制研究

催化燃烧是消除挥发性有机物的一种重要技术，而实际反应体系中存在的高浓度水汽在大部分情况下抑制了催化剂活性。由于对水汽在反应体系中的作用机制还缺乏完整认识，导致催化剂抗水能力难以提高。申请人前期工作发现水汽在某些Pt催化剂上丙烷催化燃烧中表现出明显差异的活性促进或抑制作用，且与Pt分散度和载体性质等因素密切相关。因此本项目以Pt/MOx (M = Al, Ce, Fe, Cr-Fe, Co-Fe)催化剂上丙烷催化燃烧为模型体系，考察反应气氛中水汽对催化剂结构特性和反应性能的影响。重点研究Pt物种分散度、载体性质及金属-载体相互作用、实验条件（反应温度和水汽浓度等）对水汽在催化剂上吸附活化行为的影响，探索反应条件下水汽在不同催化剂上的反应参与情况；结合反应中间体和反应历程等问题的研究，认识水汽在不同催化剂上的作用机制和影响反应行为的关键因素，为提高催化剂反应活性和抗水性能提供实验和理论支撑。

Catalytic combustion of volatile organic compounds (VOCs) over noble metal catalysts is a promising technology for the abatement of VOCs. Water vapor with high concentration is often presented in the reaction feedstock under practical reaction conditions, which usually results in suppression of the catalytic performance. Due to the lack of a thorough understanding of the roles of water vapor in the reaction, the development of efficient catalysts with good tolerance of water is challenging. In our previous research, it was found that water vapor could promote or suppress the activities of some Pt catalysts for propane combustion, which was closely related to facts such as Pt dispersion and properties of the supports. Therefore, in this project, propane combustion over Pt/MOx (M= Al, Ce, Fe, Cr-Fe, Co-Fe) catalysts will be taken as a model reaction system, to clarify the effects of water vapor on the catalyst structures and catalytic behaviors. The main goals of this project are to investigate the effects of dispersion of Pt species, nature of support and metal - support interaction and experimental conditions (reaction temperature and concentration of water vapor) on the adsorption/activation of water on the catalyst surface and the involvement of water in the reaction under different reaction conditions, as well as the reaction intermediates and reaction mechanisms. Therefore, this research may provide useful information on the key factors in the design of highly active Pt catalysts with good water tolerance.