Traditional production processes of Chinese automotive lubricant manufacturers

In the 1930s, the production of lubricating oil base oil was mainly carried out using physical methods, namely the "old three sets" traditional process consisting of solvent refining, solvent dewaxing, and clay supplementary refining to produce lubricating oil base oil.

(1) Solvent refining. Solvent refining is an important step in the production process of lubricating oil, which mainly removes polycyclic aromatic hydrocarbons, resins, asphaltenes, etc. from the oil, improving the viscosity temperature properties, antioxidant stability, residual carbon value, color and other properties of lubricating oil. This process is relatively mature, and commonly used solvents include furfural, phenol, and N-methylpyrrolidone (NMP).

(2) Solvent dewaxing. The solvent dewaxing process mainly includes four parts: crystallization, filtration, solvent recovery, and freezing. Its purpose is to remove paraffin from the oil and reduce the pour point of lubricating oil base oil. This process has technical advantages in processing lighter raw materials, with high yield of dewaxed oil and high viscosity index. In order to reduce energy consumption, save operating costs, and reduce investment, domestic and foreign lubricant base oil production enterprises have adopted a combined process of solvent dewaxing and wax deoiling. In recent years, there have been significant improvements in technology such as energy conservation and improving oil and wax yields.

(3) White clay is refined and supplemented. Baitu supplementary refining is the process of fully mixing oil and Baitu at a certain temperature, utilizing the adsorption performance of the active Baitu surface, and removing nitrides, resins, asphaltenes, naphthenic acid soaps, unsaturated hydrocarbons, selective solvents, water, mechanical impurities, etc. from lubricating oil through heating, evaporation, filtration and other processes. This improves the color of the oil, reduces residual carbon, and enhances the antioxidant stability and anti emulsification degree of the oil.