1) supercritical fluid CO2 extraction and chemical extraction
(1) can be close to room temperature (35-40 ℃) and CO2 gas cloud is extracted, effectively prevent the oxidation and the dissipation of thermal sensitive material. Therefore, all components of medicinal plants are kept in the extract, and the substances with high boiling point, low volatility and easy pyrolysis can be extracted below the boiling point temperature.
(2) SFE is the cleanest extraction method. Because the whole process does not use organic solvent, the extraction material is free of residual solvent. Meanwhile, it also prevents the extraction process from poisoning human body and pollution to the environment.
(3) extraction and separation are combined into one. When CO2-SCF full of dissolved substances flows through the separator, CO2 and the extract rapidly become two phases (gas-liquid separation) due to the pressure drop, and immediately separate.
(4)CO2 is an inert gas, which does not undergo chemical reactions during extraction and is a non-combustible gas. It is tasteless, odorless, non-toxic and has good safety.
(5)CO2 is cheap, highly pure, easy to obtain, and recycled in the production process, thus reducing costs;
(6) pressure and temperature can be used as parameters to regulate the extraction process. The extraction is achieved by changing the temperature or pressure. The pressure is fixed and the material can be separated by changing the temperature. On the contrary, temperature is fixed and pressure is reduced to separate the extract. Therefore, the process is simple and easy to master, and the extraction speed is fast.
2) characteristics of supercritical fluid
(1) high extraction speed and liquid extraction, especially suitable for the separation and extraction of solid materials;
(2) operating at close to room temperature, the energy consumption is lower than that of general rectification, which is suitable for the separation of thermally sensitive substances and easy oxides;
(3) fast heat transfer rate and easy temperature control;
(4) the article suitable for the separation of volatile substances comes from the network
Carbon dioxide extraction