H2S selective oxidation to elemental sulfur over a cobalt oxide/TiO2 catalyst: Experimental and kinetic study

فاقد چكيده فارسي

Selective oxidation of H2S to elemental sulfur was studied over a cobalt oxide/TiO2 catalyst with the goal of understanding the reaction kinetics as a complementary gas sweetening process.Experimental studies were performed in the temperature range of15-290°C. In order to evaluate the catalyst performance at temperaures higher than the sulfur dew point (i.e. 180°C), the catalyst activity and selectivity toward sulfur werestudiedin the high temperature range (200-290°C). High temperature reactor tests indicated that cobalt oxide/TiO2 could be a promising candidate for H2S selective catalytic oxidation.Activity tests were also run in the low temperature range (15-140°C) and kinetic analysis of the reaction was performed using low conversion data (i.e. differential reactor regime). The kinetic study shows that the reaction order with respect to H2S and O2 are 0.8 and 0.2, respectively, and the activation energy is 25.4 kJ/mol. Activation energy on bare TiO2 was also measured and indicated the important role of support on the catalyst performance. A steady state kinetic model was developed to predict H2S concentration and surface coverages on the catalyst surface under different operating conditions.