Without any organic solvents and halide,the oxidation of thiophenic sulfur into sulfone which would be extracted by the ionic liquid catalyzed by Na2WO4·2H2O with mass fraction of 30% hydrogen peroxide in acidic ionic liquid [(CH2)4SO3HMIm]TSO was investigated.Effects of temperature,reaction time and amount of catalyst on the reaction of oxidative desulfurization were also investigated.The optimal reaction conditions are as follows: 3 mL oil sample(500 μg/g sulfur content),the ratio of 40∶1 for n(IL)/n(Na2W...