Selective Oxidation of Hydrogen Sulfide to Sulfur on Vanadium-Based Catalysts Containing Tin and Antimony

Abstract

Oxidation of hydrogen sulfide to sulfur was investigated over a series of mixed-metal oxide catalysts containing vanadium, tin, and antimony. These catalysts were prepared by a coprecipitation method. V/Sn/Sb ternary oxides exhibited 100% sulfur yield over a wide range of temperature (180−240 °C when weight hourly space velocity was 0.0245 mol of H2S/g of catalyst per h), which was superior to the binary oxides of V/Sn, V/Sb, and Sn/Sb. In addition, V/Sn binary oxides had a better sulfur yield than the corresponding single oxides. For V/Sn and V/Sn/Sb catalysts, Brunauer−Emmett−Teller measurements indicated that catalyst surface areas increased linearly with the Sn/V atomic ratio and temperature-programmed reduction studies showed that the reducibility of VOx species increased with the tin content. These two factors should contribute to the better catalytic behaviors of the V/Sn and V/Sn/Sb catalysts in H2S oxidation. The presence of 30 vol % water vapor decreased the catalyst activity but had little effect on the maximum sulfur yield. Results of X-ray diffraction and scanning electron microscopy suggested that the ternary oxide catalysts were stable during the reaction.