Recovery pretreatment method of waste lubricating oil

The invention relates to a recovery pretreatment method of waste lubricating oil and belongs to the technical field of lubricating oil recovery. The pretreatment method of the waste lubricating oil comprises the following steps: a, mixing silica gel with the waste lubricating oil to obtain a mixture; and b, allowing the mixture obtained in step a to stand, and performing solid-liquid separation toobtain liquid and solids, wherein the liquid is used for refined recovery of lubricating oil. Preferably, the silica gel is regenerated silica gel; and more preferably, the silica gel is coarse-poresilica gel. By utilizing the silica gel for performing pretreatment on the waste lubricating oil, moisture, mechanical impurities, ash, colloids and asphaltene impurities can be effectively removed, the impurity removal effect is obvious, and the risk of coking and pipeline blockage in the distillation process of the waste lubricating oil can be reduced. 本发明涉及种废润滑油的回收预处理方法，属于润滑油回收技术领域。本发明的废润滑油预处理方法包括如下步骤：a.将硅胶与废润滑油混合得到混合物；