Features of supercritical CO2 extraction
In the near room temperature (35-40 DEG C) and CO2 gas shadow extraction, can effectively prevent the oxidation and dissipation of heat sensitive material;
SFE is the cleanest way of extraction. Because no organic solvent is used in the whole process, there is no residual solvent in the extract. At the same time, it also prevents the toxicity and environmental pollution caused by the extraction process. It is 100% pure natural;
Extraction and separation combine into one. When the CO2-SCF of the dissolved substance flows through the separator, the CO2 and the extract rapidly become two-phase (gas liquid separation) due to pressure drop, and it is immediately separated. It not only has high extraction efficiency and less energy consumption, but also saves costs;
CO2 is a kind of inactive gas. The extraction process does not have chemical reaction, and it belongs to uncombustible gas. It is tasteless, odourless and non-toxic, so it is safe and good;
CO2 is cheap, high purity, easy to get, and circulate in the process of production, thus reducing the cost;
Fast extraction speed
Both pressure and temperature can be used to adjust the parameters of the extraction process. The purpose of extraction is achieved by changing the temperature or pressure. The pressure is fixed, changing the temperature can separate the material. Otherwise, the temperature is fixed, the pressure is reduced, the extract is separated, so the process is simple and easy to grasp, and the extraction speed is fast.
As the most widely used fluid in today’s extraction technology, supercritical CO2 extraction is not only safe, non-toxic, and cheap, but also has the following obvious advantages compared with conventional extraction methods:
- The room temperature reaches 34 ~ 39 degrees Celsius. During our extraction process, it is wrapped by CO2 extraction gas, so that the heat-sensitive substances will not be oxidized and degraded. It can completely retain biological activity and extract substances with high boiling point, low volatility and easy pyrolysis at a temperature far below its boiling point;
- The extraction method is environmentally friendly and green, no organic solvents are used, there will be no solvent residues, and the process will not cause harm to the human body and cause pollution to the environment, and it is safe and reliable.
- Extraction and separation are combined into one. When the CO2 fluid full of dissolved substances enters the separator, the CO2 and the extract quickly become two-phase (gas-liquid separation). By adjusting the pressure or temperature, they are separated immediately, which not only has high extraction efficiency, but also consumes less energy and improves production efficiency. Reduced costs.
- CO2 extraction is an inert gas, there is no chemical reaction in the extraction process, it is a non-flammable gas, odorless, odorless, non-toxic, and very safe;
- Strong function, high efficiency, fast time and short production cycle.
- The process is simple, easy to master, and the extraction speed is fast. As long as the temperature and pressure are changed, the separation can be achieved.
- The anti-oxidation and sterilization functions of supercritical CO2 extraction are still very good, which can ensure and improve product quality;
The law of the solubility of supercritical CO2 to different substances
Of course, supercritical CO2 extraction technology is not a general extraction technology, it has its scope of application like any other technology. We need to determine whether it is suitable for use according to its solubility in different substances.
It is worth reminding everyone that the solubility of supercritical CO2 to different substances is as follows:
- Lipophilic and low boiling point components can be performed below 10 MPa, just like the aroma components in natural plants and fruits.
- Among benzene derivatives, phenols with three hydroxy groups and compounds with one carboxyl group and two hydroxy groups are extractable, but not if it is a compound with one carbonyl group and more than three hydroxy groups.
- Substances with strong polarity, like sugars, are difficult to extract below 40 MPa. The higher the relative molecular weight of the compound, the more difficult it is.