Supercritical CO2 fluid extraction technology is a new separation technology in modern chemical separation. It has the characteristics of fast mass transfer rate, strong penetration ability, high extraction efficiency and low operating temperature. This technology has been widely used in medicine, food, chemical industry and other industries.
Supercritical CO2 fluid extraction device is equipment used for supercritical fluid extraction. Its main extraction process consists of extraction and separation. In the extraction equipment, at a specific temperature and pressure, the raw materials are brought into contact with the supercritical fluid. When the dynamic balance of the material components between gas and liquid is reached, the temperature and pressure are adjusted to separate the extraction product from the supercritical fluid to complete the supercritical process. The entire process of extraction.
Types of supercritical fluids
As a supercritical fluid of extracting solvents and reactive fluids, it must be selected according to the characteristics and adaptability of the fluid. There are many types of substances that can be used as supercritical fluids. For some reasons, a series of factors such as solubility, selectivity, critical point data and chemical reactions are needed. Although there are many fluids that can be used as supercritical extraction solvents, there are only a dozen types of actual use. , H₂O, propane, etc.
The seven conditions of the supercritical fluid used for extracting agent should be available
- The chemical properties are stable and have no corrosiveness to the equipment and do not respond to the extract;
- The critical temperature is close to normal temperature or operating temperature, and it should not be too high or too low;
- The operating temperature should be lower than the decomposition temperature of the extraction solution;
- Low critical pressure to save power costs;
- High selectivity, the ability to selectively extract targets;
- The solubility of the extraction solution is strong, and the quality is good;
- The critical point of the solvent is lower than the critical point of the extract, and it is easy to separate;
Commonly used supercritical fluid CO₂ has the following characteristics:
The critical temperature of CO₂ is 31.06 ° C, which can achieve supercritical fluid technology operations near room temperature to save energy consumption, so the requirements for equipment are relatively low;
The density of the supercritical CO₂ fluid has a strong density, has strong dissolution capacity for most solutes, has a high quality transmission rate, but the solubility of water in the CO₂ phase is small, which is conducive to the use of near -critical or supercritical CO₂ to extract extraction Separate organic water solution;
CO₂ also has the characteristics of non -flammable, cheap, non -toxic, good chemical stability, and is easily separated from the extraction product. Because of the above characteristics, supercritical fluid CO₂ is currently the most widely used supercritical fluid for extracting agents.
conclusion
Ultra -critical CO2 fluid extraction technology is a new type of separation technology in modern chemical separation. It has the characteristics of fast quality rate, strong penetration ability, high extraction efficiency, and low operating temperature. Waiting for industries.