Recent Advances on Catalysts and Systems for the Oxidation of Thiophene Derivatives in Fuel Oil with Molecular Oxygen

The oxidation of thiophene (TH) and its derivatives is vital in the oxidative desulfurization (ODS). As a safer and greener oxidant with lower cost, molecular oxygen has been employed in the ODS process as a substitution of H2O2 or other organic hydroperoxide in many research works in recent years. However, the activation of dioxygen under mild conditions is still not an easy problem to solve. In this contribution, we reviewed reports on novel catalysts or systems for aerobic oxidation of TH and related sulfur compounds developed in recent years. The catalysts and systems are classified to five types and the component, catalytic activity and reaction mechanism are illustrated briefly in each part. Keywords: Oxidation, thiophene derivatives, molecular oxygen, aldehyde, photocatalyst, polyoxometalates, metal-free catalyst.