Petroleum is one of the most important natural resources for human beings, while the contained sulfur heteroatoms lead to a series of problems1. Therefore, a desulfurization process to reduce sulfur content is mandatory for clean petroleum utilization. Hydrodesulfurization is currently mature in industry, while this process is costly, energy intensive and environmentally unfriendly due to CO2 emission and H2S production2,3. Alternative cost-effective desulfurization process with environmentally

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... benign sulfur-containing products remains unreported. Here we demonstrate that the desulfurization of a heavy oil model compound dibenzothiophene can be successfully achieved under methane environment over creatively designed dual catalyst system, generating a new sulfur-containing product CS2. Control experiments indicate that the presence of methane as well as catalyst components for direct desulfurization and methane activation are all required. The reaction process is better understood by extensive evidences from isotope labeling experiments, catalyst and product characterizations, density functional theory calculations and verification experiments, based on which a reasonable catalytic mechanism is proposed. It is found that methane-assisted desulfurization requires more stringent conditions, where sulfur vacancy abundance, methane activation capability and surface sulfur transfer are all indispensable. This study pioneers a transformational desulfurization route, which is more economically and environmentally attractive for petroleum processing industry.