Effect of VOx surface density and structure on VOx/TiO2 catalysts for H2S selective oxidation reaction

Abstract

The correlation between the physico-chemical properties of VOx/TiO2 catalysts and the selective catalytic oxidation of H2S was investigated. Among the types of commercial TiO2 tested, the best catalytic activity was exhibited by TiO2 (B), and the optimal vanadium content was 10wt%. The VOx surface density range where maximum oxidation efficiency was achieved was about 2.69–18.09 VOx‧nm−2, where monomeric VOx and crystalline V2O5 were appropriately present in the VOx/TiO2 vanadium structure. This indicates that at maximum oxidation efficiency the VOx/TiO2 catalyst and the VOx surface density can be used to control the VOx structure on the catalyst surface. However, as the conversion of H2S into selective elemental sulfur causes sulfur to be deposited onto the VOx/TiO2 catalyst surface, the high initial reactivity and durability did not converge.