The fabrication of IMo6@iPAF-1 as an enzyme mimic in heterogeneous catalysis for oxidative desulfurization under O2 or air

Abstract

Na₅[IMo₆O₂₄]·3H₂O and a porous aromatic framework (iPAF-1) were used to build an off-the-shelf building material (IMo₆@iPAF-1) to realize the highly efficient oxidation of organic sulfurs like oxygenase. The synergy between IMo₆ and iPAF-1 resulted in a higher BET surface area, hydrophobic microenvironment, and redox sites to show higher activity in aerobic oxidative desulfurization with almost 100% removal of model organic sulfurs under atmospheric pressure with almost 246 times higher TOFs compared to IMo₆. It also showed efficiency in the desulfurization of gasoline and diesel to give very low S contents of 7.1 and 7.6 ppm with 99.3% and 99.4% removal, respectively, at 100 °C for 6 h. More importantly, IMo₆@iPAF-1 could also catalyze desulfurization using concentrated O₂ mixed with N₂ or air instead of pure O₂ with better safety and economics, while as low as 4.9 and 6.9 ppm S contents were achieved for gasoline and diesel, respectively. The special surroundings of IMo₆@iPAF-1 repelled the sulfone product and allowed it to perform with the same efficiency when recycled without any treatment of the used catalyst.