Copper tungstate was prepared by direct precipitation method at room temperature. The sample was treated with high temperature calcination and activation with hydrogen peroxide in order to improve the oxidative desulfurization activity. Then the oxidative desulfurization of dibenzothiophene (DBT) from model oil was carried out using the activated CuWO4 as catalyst, hydrogen peroxide as the oxidant, and imidazolium fluoroborate ionic liquid as extracting agent．The reaction conditions，including temperature, amount of catalyst and oxidant, types of extractant and sulfides were also studied．The results indicate the optimized desulfurization conditions of 0.4 mL of hydrogen peroxide, 0.02 g of catalyst, imidazole tetrafluoroborate as the extractant at 70 ℃ for 60 min, and the desulfurization rate can reach 93%. In addition, the desulfurization rate remains above 82% when the catalyst was reused for five times.

The pretreatment of spent lubricating oil to remove part of the water and impurities was carried out firstly, then the flash device are used for further removal of water, followed by the distillation in atmospheric and vacuum distillation unit. A lowfreezingpoint, high stable light diesel were produced in the atmospheric distillation zone; different kinds of lubricating base oils which are all available resources were produced by vacuum distillation segment combined with complex agent refiningalkaline cleaningclay refining process. Additives were added finally to improve the oil quality. The additional purification process conditions were identified: the mass fraction of acid solvent 4.5% which contains the mass fraction complexing agent 1.5% for pickling; 1% NaOH aqueous solution with its mass fraction of 40% were added for alkaline cleaning at 40 ℃, then 3% clay was added and stirred for 25～30 min at the temperature less than 120 ℃. This processing technology not only reduces the pollution effectively, but also greatly improves the reutilization of waste oil.