Supercritical CO₂ extraction
Steps and principles of operation
Supercritical CO₂ extraction is a modern and high-tech method to extract useful components from various organic raw materials, such as plants, to obtain food ingredients and even pharmaceutical components. The process is based on the use of carbon dioxide (CO₂) in a supercritical state as a solvent when its properties are between gaseous and liquid states.
Preparation
The solid feedstock is finely ground to increase the interaction surface with CO₂.
Read More Extractor Filling
The crushed solid is placed in an extractor, which is then filled with carbon dioxide until the desired pressure and temperature are reached.
Read More Extraction
When the extractor reaches the desired pressure and temperature, the carbon dioxide goes into a supercritical state and begins to act as a solvent, extracting the target substances from the material.
Read More Separation
The extracted substances are separated from the carbon dioxide by reducing the pressure, resulting in two phases: a gas phase and a liquid phase. The substances are separated in the liquid phase and the carbon dioxide is recirculated back to the extractor.
Read More Condensation and Recuperation
The supercritical CO₂ is condensed and recovered for reuse. This reduces the environmental load and improves process efficiency.
Read More Cleaning
If required, the resulting solution can be further purified, for example by distillation or extraction with other solvents.
Read More Supercritical CO₂ extraction is an efficient and environmentally friendly method of extracting useful components from raw materials. It produces high-quality products with minimal environmental impact and without the use of chemical solvents. Thanks to the ability to control the process conditions, the method also offers a high degree of flexibility and can be adapted to different raw materials and applications.
1. Raw Material Preparation
The first step in supercritical CO2 extraction is raw material preparation. The raw material must be thoroughly cleaned of impurities and pre-crushed to a certain particle size. This increases the contact surface with CO2, which increases the efficiency of extraction. It is also important to choose the right conditions for the raw material, such as temperature and pressure, to ensure the best results.
2. Extractor Filling
The next step is filling the extractor, where the raw material and supercritical CO2 are mixed. Different types of extractors have different designs and volumes, but all are designed to create optimal extraction conditions. During this step, it is important to control pressure and temperature to ensure that the supercritical CO2 is correct.
3. Extraction
When certain pressure and temperature parameters are reached, the supercritical CO2 penetrates the raw material and dissolves the target components. The duration of the extraction process can vary from a few minutes to several hours, depending on the properties of the raw material and the concentration of the desired components. During this time, CO2 is continuously circulated through the extractor to ensure maximum extraction of useful substances.
4. Separation
After completion of the extraction process, the mixture of CO2 and extract is redirected to the separator. Here the supercritical CO2 is separated from the target components. This is achieved by reducing the pressure and/or temperature, which leads to a separation of the extract from the CO2. The result is a high-quality concentrate of useful substances, which can then be used for various purposes.
5. Condensation and Recuperation
After separation, the CO2 is condensed and recovered for reuse in the extractor. This reduces the cost of the process and makes it more environmentally friendly, since carbon dioxide is a safe and recoverable resource. CO2 recovery also reduces the amount of waste and the environmental impact.
6. Cleaning
The resulting extract after separation can be further purified to remove unwanted substances or to improve the quality of the final product. Purification methods may include filtration, distillation, chromatography and other techniques, depending on the requirements for the final product.