Review of oxidative desulfurization techniques for fuels – a future perspective

This review explores the critical role of oxidative desulfurization (ODS) in enhancing fuel quality by effectively removing sulfur compounds from liquid fuels. It highlights the environmental and health impacts of sulfur in fuels, emphasizing the necessity for advanced desulfurization techniques. The ODS techniques are cost-effective and promising for the removal of aromatic sulfur compounds in liquid fuels. Typically, they are conducted under relatively mild reaction conditions. The paper discusses traditional methods and their limitations, focusing on innovative ODS strategies, including catalytic processes utilizing metal oxides and metal–organic frameworks (MOFs). Emerging techniques such as ultrasound-assisted and photocatalytic ODS are presented as promising solutions for efficient sulfur removal, paving the way for cleaner fuel production. Combining these methods to create sono-photocatalytic desulfurization is projected to motivate the desulfurization of Dibenzothiophene (DBT) and its derivatives in liquid fuels. In the future, the ODS techniques such as ultrasound-assisted ODS (UAOD) or sono-photocatalytic desulfurization can be employed after hydro-desulfurization (HDS) to oxidize residual sulfur compounds into polar sulfoxides or sulfones, which are easily removed through extraction or filtration and the removal efficiency increases.