Project description: Deodorized distillate (DOD) is a by-product of the oil refining process. It is rich in fatty acids (50 - 70%), glycerides (10-25%), natural tocopherols (5-10%), sterols (5- 12%) and other impurities. Our country is a major oil producer, with an annual refining capacity of nearly 10 million tons and producing 600,000 tons of DOD. On the one hand, this technology uses the grease waste to produce biodiesel and high value-added tocopherols and sterols. On the other hand, environmental pollution caused by emissions can be effectively reduced; at the same time, the entire process meets modern chemical requirements that are green and pollution-free. Innovative: Supercritical fluid is a special state of matter between gas and liquid. Its density is similar to that of liquid and has a strong interaction with solute molecules; its viscosity is close to that of gas, and its mass transfer rate is very high, making Reaction, extraction and other processes are completed efficiently and quickly. Compared with traditional solvent extraction methods, supercritical CO2 extraction has no solvent residue; the extraction temperature is close to room temperature, which does not affect the activity of organisms; and CO2 is recycled, saving a lot of solvent expenses. Biodiesel (fatty acid methyl ester) is prepared by methylesterification and alcoholysis of fatty acids and glycerides with methanol respectively, which can partially replace fossil fuels. The technology utilizes the grease waste to produce biodiesel and tocopherol and sterol with high added value. Tocopherol, also known as vitamin E, is an oil-soluble natural antioxidant that can maintain normal reproductive organ function; sterols have immunomodulatory, anti-tumor, free radical scavenging effects.