High-Valent Nickel-Induced Oxidative Coupling of Hydrogen Sulfide-Containing Methane to Acetic Acid

The methane oxidative coupling activity of non-noble metals is highly susceptible to trace amounts of H2S in the feedstock. Developing H2S-resistant oxidative coupling catalysts with high activity and selectivity is crucial for enabling the use of inexpensive crude natural gas without costly H2S separation. In this study, we introduce a stable atomically dispersed nickel-based catalyst protected by strong oxygen ligands, which not only facilitates the conversion of H2S into chemical products but also promotes the oxidative coupling of methane with CO to CH3COOH in the presence of H2O2 or O2. By controlling the oxidation depth of H2S, the CH3COOH yield was improved from 7.9 to 12.9 mmol gcat -1 h-1, challenging the conventional belief that sulfur always poisons catalysts. Mechanistic studies reveal that the atomically dispersed Ni can in situ form high-valent Ni sites that preferentially oxidize H2S and activate the C-H bond of methane. Notably, the acidic environment generated by H2S oxidation enhanced the coupling reaction without metal leaching. This method is applicable to other atomically dispersed metal sites, effectively preventing H2S interaction with metal sites, which remain visually unchanged. By providing a robust solution to H2S resistance, this work provides a solid foundation for sulfur-containing feedstock upgrades.