Characterization of vanadia catalysts on structured micro-fibrous glass supports for selective oxidation of hydrogen sulfide

Abstract

Abstract This work is focused on the characterization of a novel vanadium pentoxide catalysts on a glass-fiber support. The catalyst support consists of a non-porous glass-fiber fabric covered with an additional external surface layer of porous secondary support of SiO2. The vanadia active component is synthesized from vanadyl oxalate precursor by means of an impulse surface thermo-synthesis method. Such catalysts demonstrate high activity and appropriate selectivity in the reaction of H2S oxidation by oxygen into sulfur in the practically important temperature range below 200°C. According to the characterization data, the freshly prepared vanadia catalyst partially consists of mostly the amorphous and badly ordered vanadia with some part of the wellcrystallized V2O5 phase. Under the reaction conditions the main part of vanadia in the catalyst remains in the amorphous V2O5 form, while the less part becomes reduces into of VO2 and other vanadium oxides (such as VO, V2O3 V3O7 and V4O9). Most probably, the crystallized V2O5 in course of reaction is responsible for the deep oxidation of hydrogen sulphide into SO2, while the lower vanadium oxides promote the selective H2S oxidation into elemental sulfur.