Mechanism of sulphur dioxide oxidation over supported vanadium catalysts

Abstract

The mechanism of SO₂ oxidation to SO₃ over industrial vanadium catalysts has been elucidated on a molecular level using ⁵¹V, ¹⁷O and ²³Na n.m.r., i.r. and relaxation kinetic methods. The following reaction scheme has been shown to describe quantitatively the whole set of experimental data: [graphic omitted] According to this scheme three types of binuclear vanadium(v) complexes are involved in the catalytic cycle: the oxocomplex, sulphite complex and peroxocomplex. The rate constants for all the steps of the catalytic cycle have been determined. The data obtained provide guidelines for further improvement of vanadium catalysts as applied to particular conditions of their operation.