Efficient electro-catalytic desulfurization by in-situ oxidant generation

In this study, we present an extraction-coupled electro-catalytic oxidative desulfurization (EC-EODS) system that achieves efficient sulfur removal from fuel oils without external oxidants. The system utilizes an electrolyte composed of ionic liquids (ILs), NaCl, and H 2 SO 4 , integrating extraction and electrochemical oxidation to effectively remove different aromatic sulfur compounds with sulfur removals of 100%. Additionally, H 2 is co-produced at the cathode, supporting refinery processes and reducing H 2 storage and transportation costs, thereby improving economic viability. Detailed mechanism analysis shows that IL selectively extracts and concentrates sulfur compounds, while NaCl and H 2 SO 4 facilitate ClO - generation, serving as the in-situ oxidant. The EC-EODS system operates without external catalysts, relying on graphite electrodes that generate superoxide radicals from ClO - . Moreover, a strategy for the separation of desulfurization products as well as the electrolyte is proposed as well. The EC-EODS system offers a sustainable, high-efficiency strategy for desulfurization, with economic benefits through sulfur oxidation and H 2 co-generation. A novel extraction-coupled electrocatalytic oxidative desulfurization (EC-EODS) system achieves rapid, energy-efficient sulfur removal from fuel oils under mild conditions, with integrated product separation and electrolyte regeneration, offering a sustainable approach for cleaner fuel production • Novel EC-EODS system integrates extraction and electrochemical oxidation. • The EC-EODS system generate ClO - in situ for electrochemical oxidation. • 100% sulfur removal achieved within 20 minutes without external oxidants. • The system operates without external oxidants or catalysts, lowering costs. • Hydrogen co-production was gained in the EC-EODS system.