Project Introduction: Deodorized distillate (DOD) is a byproduct of the oil refining process, rich in fatty acids (50 - 70%), glycerides (10-25%), natural tocopherols (5-10%), and sterols (5-12%) as well as other impurities. China is a major producer of fats and oils, with an annual refining capacity of nearly ten million tons, generating 600,000 tons of DOD. This technology, on one hand, utilizes this waste oil to produce biodiesel and high-value tocopherols and sterols. On the other hand, environmental pollution caused by emissions can be effectively reduced; at the same time, the entire process complies with the requirements of green and pollution-free modern chemical industry. Innovation: Supercritical fluid is a special state of matter between gas and liquid, with a density similar to that of the liquid phase and strong interaction with solute molecules; its viscosity is close to that of a gas, resulting in a very high mass transfer rate, which can efficiently and quickly complete processes such as reactions and extractions. Compared to traditional solvent extraction methods, supercritical CO2 extraction does not leave any residual solvents; the extraction temperature is close to room temperature, which does not affect the activity of organisms; CO2 is recycled, saving a significant amount of solvent expenses. Biodiesel (methyl esters of fatty acids) is produced by the transesterification and saponification reactions of fatty acids with methanol and glycerides, respectively, and can partially replace fossil fuels. This technology utilizes this waste oil to produce biodiesel as well as high-value tocopherols and sterols. Tocopherols, also known as vitamin E or gamma-tocopherol, are oil-soluble natural antioxidants that can maintain the normal function of reproductive organs; sterols have immune-regulating, anti-tumor, and free radical scavenging effects.