Highly efficient Ag/Ce-Zr catalyst for catalytic oxidation of NVOCs:balance of redox ability and acidity  

作　　者：Xiao-Han Guo Si-Yuan Sun Mei-Xing-Zi Gao Qi-Guang Dai Wang-Cheng Zhan Li Wang Yun Guo Ai-Yong Wang Yang-Long Guo 

机构地区：[1]State Key Laboratory of Green Chemical Engineering and Industrial Catalysis,School of Chemistry and Molecular Engineering,Research Institute of Industrial Catalysis,East China University of Science and Technology,Shanghai,200237,Republic of China

出　　处：《Rare Metals》2024年第12期6473-6485,共13页稀有金属(英文版)

基　　金：financially supported by the Fundamental Research Funds for the Central Universities;National Key Research and Development Program of China (Nos.2023YFA1508500,2023YFC3707500 and 2022YFB3504200);the National Natural Science Foundation of China (Nos.22106101 and U21A20326)。

摘　　要：Due to the presence of nitrogen,nitrogen-containing volatile organic compounds(NVOCs) are more difficult to remove than conventional volatile organic compounds(VOCs).Both catalytic activity and N_(2)selectivity should be considered in the design of suitable catalysts.A series of Ag/Ce-Zr solid solution(Ag/CZ)catalysts were prepared and applied to the catalytic oxidation of N,N-dimethylformamide(DMF).Redox ability and acidity were regulated by modifying the Zr content.The introduction of Zr promoted the formation of active oxygen species until the molar ratio of Zr reached 0.5,after which the formation decreased.Moreover,adding Zr increased the number of weak and medium acidic sites,which significantly improved DMF adsorption.The improved DMF adsorption hindered the combination of nitrogen and active oxygen,thus reducing the generation of NO_(x)effectively.Therefore,the Ag/CZ(5:5) catalyst,with suitable redox ability and acidity,exhibited the highest activity(T_(90)=176℃),the lowest elimination temperature of organic compounds(T=255℃),satisfactory N_(2)yield(95%-75% in the range of 240-400℃),and outstanding stability under both common and humid conditions(at least50 h).The reaction mechanism was investigated based on the in situ diffuse reflectance infrared Fourier transform spectroscopy(DRIFTS) results.During the catalytic oxidation of DMF,the surface lattice oxygen directly participated in the dehydrogenation and dissociation of the C(O)-N bonds.The generated dimethylamine(DMA) was then oxidized by active oxygen species to form the final product.

关 键 词：Catalytic oxidation VOCs NVOCs Ce-Zr solid solution Redox ability ACIDITY 

分 类 号：O64[理学—物理化学]