A Green Route for Wasted Sulfur Consumption: Kinetic Modelling of Methyl Mercaptan Synthesis from Refinery H2S Streams over the K2Wo4/Al2O3 Catalyst

The kinetics of methyl mercaptan production from a reaction between methanol and hydrogen sulfide in the presence of a K2Wo4/Al2O3 catalyst was experimentally studied. Waste streams containing sulfur due to sour gas sweetening in the Nori refinery complex were used instead of pure H2S. This reaction can eliminate the emission of sulfur-containing compounds into the environment and convert them into useful products. The experiments were performed over a fixed-bed reactor at various temperatures and a pressure of 8-10 bars. The values of kinetic parameters estimated by the regression between the kinetic models and the experiments within the ranges have been reported in the literature. The activation energies for methyl mercaptan and dimethyl sulfide were 53.11 and 129.55 (kJ/mol), respectively. ASPEN simulation showed that the molar flow rates of H2S and methanol (reactants) decreased at the length of the reactor, while this trend for the products (methyl mercaptan, DMS, and H2O) was reversed. The correlation coefficients indicated that the parameters and the model were significant and reasonable for reactor design. The results showed that sulfur-containing waste streams could be used instead of pure H2S streams. This substitution not only provides a supply for replacing pure H2S streams but also contains the emission of poisonous sulfur compounds into the environment.