Direct synthesis of methanethiol from H2S-rich syngas over sulfided Mo-based catalysts

The direct synthesis of methanethiol from H2S-rich syngas was investigated over sulfided Mo-based catalysts supported on SiO2. K-promoted Mo/SiO2 catalysts exhibited a high activity for the synthesis of CH3SH. The incorporation of cobalt into the K–Mo/SiO2 catalyst increased the catalytic activity, but slightly decreased the selectivity to methanethiol. The selected catalysts were characterized by using X-ray diffraction (XRD), CO temperature-programmed desorption (CO-TPD), electron spin resonance (ESR), and X-ray photoelectron spectroscopy (XPS) techniques. The results showed that the potassium interacts with Mo component and increases the active sites for the CH3SH synthesis by changing the concentration of Mo5+ species after sulfidation. A mechanism for the synthesis of CH3SH was proposed.

Graphical abstractOne-step synthesis of CH3SH from the reaction of H2S-rich syngas (H2S/CO/H2 mixtures) was investigated over the sulfided supported K–Mo catalysts. Compared to the CH3OH–H2S route for the synthesis of methanethiol, this method skips the step of the synthesis of CH3OH from syngas.Figure optionsDownload full-size imageDownload as PowerPoint slide