Commercially available molybdic compound-catalyzed ultra-deep desulfurization of fuels in ionic liquids

摘要

A simple liquid-liquid extraction and catalytic oxidative desulfurization(ECODS)system composed of molybdic compound,30% H2O2 and l-butyl-3-methylimidazolium tetrafluoroborate([bmim]BF4)has been found suitable for the ultra-deep remo-al of dibenzothiophene(DBT)in model oil.The precatalyst of molybdic compound was oxidized with H2O2 to form peroxomolybdic compound,which was soluble in ionic liquid and dissol-ed in oil.The sulfur-containing compounds,such as benzothiophene(BT),DBT and 4,6-dimethyldibenzothiophene(4,6-DMDBT),in model oil were extracted into ionic liquid phase and oxidized to their corresponding sulfones by peroxomolybdic compound.In the case of the system containing model oil(DBT),H2O2,Na2MoO4·2H2O and[bmim]BF4,extraction and catalytic oxidation increased the sulfur remo-al to 99.0%,which was remarkably superior to mere solvent extraction with IL(13.6%)or catalytic oxidation without IL(4.1%).The desulfurization system could be recycled five times with very little decrease in activity.