Solvent dewaxing refers to the process of diluting and cooling the base oil or other raw materials that require dewaxing through a special solvent, causing the wax to crystallize and precipitate, thereby reducing the freezing point of lubricating oil. Previously, people wanted to separate oil and wax through distillation, but due to the similar electricity consumption of wax and the fraction of lubricating oil, distillation could not achieve the desired effect. The solidification point of wax is higher than that of lubricating oil. This law can be used to gradually reduce the temperature of the base oil to allow wax to crystallize and precipitate from the lubricating oil. However, a challenge with this method is that the viscosity of the lubricating oil is high, while the precipitated wax crystals are small. It is not very easy to separate wax from the oil. At this point, we can use a special solvent to separate the two, which must have the characteristics of being able to dissolve and dilute lubricating oil well, while being insoluble in wax or vice versa. For example, benzene based chemical solvents can effectively dissolve lubricating oil but have little solubility in wax, while ketone based chemical solvents are the opposite. Benzene based solvents are commonly used in industrial production.
