Aerobic oxidative desulfurization coupling of Co polyanion catalysts and p-TsOH-based deep eutectic solvents through a biomimetic approach

A unique coupled redox biomimetic catalytic system using the Anderson-type polyoxometallate (POM) (NH4) 3Co(OH) 6Mo6O18 and p-toluenesulfonic acid (p-TsOH)-based deep eutectic solvents (DESs) as cocatalysts, which served as electron donors and electron-transfer mediators (ETMs), can selectively oxidize the sulfides in diesel into their corresponding sulfones. The use of coupled redox systems with ETMs facilitates the reaction process by transporting electrons from Co-POM to the oxidant along a lowenergy pathway, making DBT prone to oxidize to DBTO2. The biomimetic system demonstrates outstanding desulfurization performance with oxygen as an oxidant in the absence of sacrificial agents and under mild conditions.