YUAN Weijie , LU Hanfeng , ZHANG Bo, CHEN Yinfei

(College of Chemical Engineering and Material Science, Zhejiang University of Technology, Hangzhou 310014 , Zhejiang , China)

Abstract: In order to improve activity and selectivity of gas phase catalytic oxidation of 3-picoline to nicotinic acid on V₂O₅/TiO₂, a series of V₂O₅/TiO₂ catalysts doped with different Cr content were prepared by impregnation method, and characterized by XRD, BET, H₂-TPR, NH₃-TPD. The results showed that a new crystalline phase CrVO₄ appeared on the Cr-doped catalysts, which reduced V₂O₅ and TiO₂ grain size, and increased the acidity of catalysts. A small amount of Cr doping would promote the activity of the lattice oxygen of V₂O₅, and improved the yield and selectivity for nicotinic acid. But excessive Cr doping would increase the number of surface oxygen, and lead to a decline in selectivity of nicotinic acid.Yield ofNicotinic acid can reached 77% on V₂O₅/TiO₂ with 2wt% Cr at 260℃.

Key words: 3-picoline; gas-phase oxidation; nicotinic acid; V₂O₅/TiO₂; chromium doping

E-mail: yfchen@zjut.edu.cn

Journal of Molecular Catalysis, Vol. 25, Issue 4, 2011, 322~327