Novel application of MgH2/MoS2 hydrogen storage materials to thiophene hydrodesulfurization: A combined experimental and theoretical case study

Highlights: • Solid-state hydrogen storage materials are employed for catalytic transfer hydrogenation. • Coupling effect occurs between MgH₂ decomposition and thiophene hydrogenation. • Energy barriers in the minimum energy path for thiophene hydrodesulfurization are • Thiophene desulfurization with MgH₂ is both thermodynamically allowed and kinetically favored. In addition to serving as an important energy carrier, hydrogen storage material also has the potential to be used as an effective solid reducing agent. This paper is concerned with the application of MgH₂/MoS₂ hydrogen storage materials to thiophene desulfurization through catalytic transfer hydrogenation. The hydrogen content of the as-prepared MgH₂/MoS₂ composites is determined to be 6.15 wt% with a dehydrogenation peak temperature of 402 °C. Taking MgH₂ as hydrogen donor, thiophene hydrodesulfurization has taken place at atmospheric pressure and at the temperature lower than the onset desorption temperature, indicating that a coupling effect occurs between MgH₂ decomposition and thiophene hydrogenation. It is further revealed that sulfur removal in thiophene under the studied condition preferentially proceeds via direct desulfurization (DDS) route. Our density functional theory (DFT) calculations manifest that energy barriers of the minimum energy path for thiophene hydrodesulfurization are all <1.35 eV. This exploratory case study demonstrates the feasibility of catalytic transfer hydrogenation using solid-state hydrogen storage materials.