Vanadium-Based Mixed-Oxide Catalysts for Selective Oxidation of Hydrogen Sulfide to Sulfur

The selective oxidation of hydrogen sulfide to sulfur was studied over three vanadium-based mixed-oxide catalysts, including the binary oxides of vanadium−molybdenum, vanadium−bismuth, and vanadium−magnesium. The catalytic reaction was carried out in a fixed-bed reactor in the temperature range 200−300 °C. Strong synergistic phenomena in catalytic activity and selectivity were observed for the binary oxides. Under identical reaction conditions, the performances of the binary oxide catalysts within certain composition ranges were superior to those of the corresponding single-oxide catalysts. These synergistic phenomena suggest that the new compounds Mo 6 V 9 O 40, BiVO 4 /Bi 4 V 6 O 21, and MgV 2 O formed in the binary oxides are much better than the corresponding single-oxide catalysts for the selective oxidation of hydrogen sulfide. The maximum sulfur yield obtained with the vanadium-based binary mixed-oxide catalysts was 97%, which was much higher than that obtained with pure vanadium oxide (78%).