H₂S Oxidative Decomposition for the Simultaneous Production of Sulphur and Hydrogen

Abstract

The reaction parameters of H2S conversion, H2 yield and SO2 selectivity obtained by thermal decomposition of H2S in presence of oxygen have been investigated at different operating conditions such as O2/H2S molar feed ratio, residence time and reaction temperature. Experimental tests allowed to find the best values of operating parameters able to assure a high H2S conversion and a good hydrogen yield, minimizing the SO2 selectivity. The increase of the O2 concentration has determined an increase of the H2S conversion and the SO2 selectivity and a slight decrease of H2 yield. The increase of the temperature in the range 700 - 1,100 °C has improved the H2S conversion and H2 yield, with a reduction of SO2 selectivity from about 30 % to 2 %. At temperature of 1,100 °C and O2/H2S = 0.2 good performances were observed in terms of the H2S conversion (58 %), H2 yield (24 %) with a lower SO2 selectivity (~2 %).