LAUSR

Abstract Catalytic oxidation of aromatic sulfur compounds for separation from fuel oils has turned to be an important theme in environmental protection. However, most current reports focused on metal-based catalysts, resulting in high costs and potential secondary pollution to fuel oils. In this work, three metal-free bronsted acid ionic liquids were prepared and anchored onto graphene-like hexagonal boron nitride (G-h-BN) to gain metal-free, heterogeneous catalysts. The heterogenization process not only provided convenience to recycling of the catalysts, but also supplied a sharply decreased ILs dosage. Notably, the prepared catalyst [Bmim]H 2 PO 4 /G-h-BN held the best catalytic activity, a ∼100% of catalytic activity can be gained in catalytic oxidation of 4,6-dimethyldibenzothiophene (4,6-DMDBT), which has been regarded as the most stubborn sulfide in industrial hydrodesulfurization (HDS). It was also found that distractors in fuels showed almost no influence on catalytic oxidation of 4,6-DMDBT. Besides, the catalytic oxidation product was also investigated to propose a possible reaction mechanism. The heterogeneous metal-free catalyst were recycled for 5 times without significant decrease in catalytic performance.