Supercritical carbon dioxide is currently the most widely used supercritical fluid, and it is also a green solvent. Compared with traditional extraction technology, supercritical carbon dioxide extraction technology has the following advantages: the critical temperature and critical pressure of carbon dioxide are low, the operating conditions are mild, and there is less damage to the active ingredients; There is no need for repeated extraction operations, and the process is simple; supercritical carbon dioxide has the advantages of stability, non-toxicity, safety, and pollution-free, and overcomes the problems of poor purity, odor, and solvent residue in traditional solvent extraction.
Five advantages of supercritical carbon dioxide extraction
Supercritical carbon dioxide extraction technology has the following advantages:
- Environmental protection: supercritical carbon dioxide is a non-toxic, non-residual, renewable solvent, so the extraction process will not pollute the environment.
- Efficient: supercritical carbon dioxide has a high solvency power, so it can quickly and effectively extract valuable components.
- Economical: The cost of supercritical carbon dioxide extraction technology is low, and the equipment cost is not high, so it is an economically feasible extraction technology.
- Controllability: The supercritical carbon dioxide extraction process can control the extraction effect by adjusting the temperature and pressure, so as to obtain high-quality products.
- Flexibility: Supercritical carbon dioxide extraction technology can be used to extract a variety of valuable substances, including oils, fats, spices, and plant extracts.
Applications of supercritical carbon dioxide extraction
Supercritical carbon dioxide extraction technology is a technology that uses supercritical fluid (usually carbon dioxide) as a solvent to extract valuable components from substances.
The technology has wide-ranging applications in many fields, including:
- Medicine and biotechnology: In the field of pharmacy and biotechnology, supercritical carbon dioxide extraction technology is used to extract pharmaceutical raw materials and biologically active substances.
- Food and Beverage: In the field of food and beverage, this technology is used to extract edible oil, spices, and other food additives.
- Agriculture: In the field of agriculture, supercritical carbon dioxide extraction technology is used to extract valuable vegetable oils and essential oils.
- Cosmetics and personal care: In cosmetics and personal care, technology is used to extract active ingredients in skin and hair care products.
- Environment: In the environmental field, supercritical carbon dioxide extraction technology is used to purify and treat wastewater and waste gas.
Top 5 applications of supercritical carbon dioxide extraction technology
At present, supercritical carbon dioxide extraction technology has been applied in the pharmaceutical industry (such as the separation of active ingredients from medicinal plants, and the refinement of pharmaceutical active ingredients), food industry (such as decaffeination, hop extraction, edible oil extraction, pigment extraction), spices Industry (such as the refining of natural and synthetic fragrances), chemical industry (such as the separation of mixtures) and other fields.
Herbs
The active ingredients in herbal medicine mainly include alkaloids, brass, coumarin and lignans, and volatile oils. Compared with the traditional solvent extraction method and steam distillation method, the supercomputer fluid extraction method has the advantages of low operating temperature, not easy to destroy the active ingredients, no residue after the separation of the solvent and the product, short time consumption, high yield, and no pollution. , therefore, has a broad application prospect in the field of herbal medicine.
CO2 extraction experiments were carried out on herbal medicines in some laboratories in China, and the results showed that: the supercritical CO2 fluid extract has a fast onset of action and a short duration of action, and the supercritical CO2 fluid ethanol extract has a slow onset and peak time And the duration of action is longer, this phenomenon may be related to the fact that the supercritical CO2 fluid extract contains a lot of fat-soluble components, which is easy to absorb and can quickly pass through the blood-brain barrier.
The traditional Chinese medicine preparations extracted by supercritical CO2 have no obvious toxicity, and the clinical application of supercritical extracted traditional Chinese medicine formula granules is safe. Supercritical CO2 extraction technology is of great significance in promoting the development of traditional Chinese medicine formula granules.
Food industry
The food industry is the first field of supercritical fluid extraction technology to achieve industrial application. Natural food is getting more and more attention. The carbon dioxide used as a supercritical extraction agent has a series of advantages such as being non-toxic, having no solvent residue, and can be operated at room temperature. , especially suitable for the separation and refinement of natural substances in the food industry.
Spice industry
The traditional extraction methods of natural spices include steam distillation, solvent extraction, pressing and grinding, adsorption, and so on. The operating temperature of the steam distillation method is high, which easily decomposes the heat-sensitive substances in the natural fragrance, and at the same time, it is easy to lose the top fragrance components with a low boiling point and change the natural fragrance of the fragrance. The solvent extraction method has the problem of solvent residue.
The above-mentioned problems can be effectively avoided by adopting a supercritical carbon dioxide extraction method that can be carried out at room temperature, is non-toxic, has no solvent residue, and has strong selectivity and solvency.
Environmental friendly
Supercritical carbon dioxide fluid extraction technology has been widely used in environmental protection technology due to its low energy consumption, high efficiency, and good selectivity. The US EPA has gradually adopted SFE technology as a standard method to replace solvent extraction.
Other
Supercritical carbon dioxide extraction technology can be used to separate ethanol aqueous solution and acetic acid aqueous solution; treat benzene-containing wastewater, phenol-containing wastewater, and chlorine-containing wastewater to remove organic pollutants and meet emission requirements; the combination of supercritical carbon dioxide extraction and organic solvent complexation, It can be used for the removal of harmful heavy metal ions in some raw materials, soil, and radioactive wastewater. In addition, supercritical carbon dioxide extraction technology is also used in propane deasphalting, residual oil extraction, and refining in the petroleum industry.
Final words
Supercritical carbon dioxide extraction technology is an efficient, environmentally friendly, and economical extraction technology with high application value