Relationship between the molecular structure of V₂O₅/TiO₂ catalysts and the reactivity of SO₂ oxidation

Abstract

The relationship between the molecular structure of V 2 O 5 /TiO 2 catalysts and the reactivity of SO 2 oxidation was investigated. The dispersion state and surface properties of supported vanadia over V 2 O 5 /TiO 2 catalysts were studied with various experimental techniques. Isolated vanadia species were dispersed on the TiO 2 surface as Ti-O-V bonds at VO x coverage far below the monolayer. Polymeric vanadia species were then formed through the V-O-V bonds as the VO x coverage increased. SO 2 temperatureprogrammed desorption and in situ diffuse reflectance infrared Fourier transform spectroscopy were conducted to study the interaction between SO 2 and V 2 O 5 /TiO 2 . On the V 2 O 5 /TiO 2 catalysts, the turnover frequency of SO 2 oxidation was almost constant with increased VO x coverage under the condition of constant temperature. VO was demonstrated to play a critical role in the SO 2 adsorption and oxidation. A possible reaction mechanism was established in this study.Catal. Sci. Technol. This journal is

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