
In addition, the following chemical industries have also begun to use supercritical carbon dioxide extraction technology to reduce the generation of pollutants in the production process: 1. Denitrification of petroleum residual oil, 2. Recovery of crude oil, regeneration of lubricating oil, 3. Separation of hydrocarbons, extraction of coal liquefaction oil, 4. Treatment of waste liquid containing difficult-to-decompose substances.
1. Application in the food field:
In the food field, supercritical carbon dioxide extraction is mainly used for the extraction of vegetable oils (soybean oil, castor oil, palm oil, cocoa butter, corn oil, rice bran oil, wheat germ oil, etc.); extraction of animal oils (fish oil, liver oil, various aquatic oils); degreasing of food raw materials (rice, noodles, poultry eggs); separation and refining of lipid mixtures (glycerides, fatty acids, lecithin, etc.); decolorization and deodorization of oils; exchange with the help of enzymes under supercritical conditions; extraction of plant pigments and natural flavor components; decaffeination of coffee and black tea; extraction of hops; manufacture of soft drinks; concentration of fermented alcohol, etc.
The extraction of soybean oil by supercritical carbon dioxide extraction has been successful, and the product quality has been greatly improved without pollution problems. Supercritical carbon dioxide can be used to extract oils from sunflower seeds, safflower seeds, peanuts, wheat germ, palm, and cocoa beans, and the extracted oils contain neutral lipids, low phosphorus content, low coloring, and no odor. This method has a higher recovery rate than the traditional pressing method, and there is no solvent separation problem of the solvent method.
2. Application in the field of medicine:
Supercritical carbon dioxide extraction technology extracts natural medicines: Using supercritical carbon dioxide, a special alcohol substance is used as an entrainer to extract ginkgo flavonoids and ginkgo lactones. The extraction rate of this method is 3.4%, which is twice as high as the 1% of the solvent method; the process is short, and the extraction batch operation time is shortened by 11 times compared with the solvent method, which improves work efficiency; the quality of the effective ingredients of ginkgo leaves (gingko flavonoids content is 28%, ginkgo lactone content is 7.2%), are higher than the currently recognized quality standards, and there is no organic solvent residue and heavy metal residue.
3. Application in the extraction of bioactive substances:
Using supercritical carbon dioxide extraction technology to extract and concentrate EPA and DHA in sardine oil can increase EPA and DHA from the original 17% and 12% to 58% and 67% respectively. Extract egg yolk phospholipids from dry egg yolks. Under certain conditions, 67 grams of egg yolk phospholipids can be extracted from 100 grams of sample. Compared with the traditional solvent method, the purity and extraction rate are improved, and the product color is good.
β-carotene is extracted from tomato rot waste, with 5% ethanol as the entrainer, and the extraction rate is 50% under certain conditions. The results show that supercritical carbon dioxide extraction technology has the advantages of high efficiency, fast speed, simple process, and pure product color and taste.
4. Application in other aspects:
In addition to the several application fields introduced above, carbon dioxide supercritical extraction technology is also applied to many other fields. Such as the cosmetics industry, preparation of fine particle materials, pesticide residue analysis, and precision instrument cleaning. More promising applications are being developed. With the continuous deepening of people's research on supercritical extraction technology and the continuous improvement of technology, supercritical extraction technology will be more widely used in the future.