Thermodynamic Reaction Study of Conversion of H₂S and CO₂ and the Promoting Effect of Light on the Reaction

Abstract

H2S and CO2 are common coexisted gases widely existing in natural gas resources, and they need to be treated harmlessly. The traditional Claus treatment process only focuses on H2S treatment but ignores CO2. This article systematically conducted theoretical thermodynamic research on the thermocatalytic conversion of H2S and CO2. It was found that increasing the reaction temperature and H2S ratio would have a positive impact on the reaction, while increasing the pressure would lead to a decrease in the conversion rate of reactants and product yield, and introducing COS into the feed gas could have a promoting effect on the reaction. Furthermore, 5%Mo/Al2O3 catalyst was used to preliminarily explore the thermal and photothermal catalysis for H2S and CO2 conversion. The results showed that the photothermal catalysis significantly promoted the production of syngas (H2 and CO), and suppressed COS production in contrast to thermal catalysis. This indicates that the introduction of light could effectively convert H2S and CO2 into high‐value product syngas, providing important reference value for further research on the conversion of H2S and CO2.