What's Supercritical CO2 Fluid Extraction?


Principle of Supercritical CO2 Fluid Extraction

Supercritical CO2 fluid extraction is the process of separating one form of a substance from another using CO2 as a solvent. This process establishes phase changes in CO2 by regulating pressure and temperature to derive a range of end products. The resultant phase changes set up an environment that separates varying weights of components in the raw material.

This supercritical CO2 fluid extraction process entirely employs the use of CO2, which is sometimes modified by co-solvents, like methanol or ethanol, as a major supercritical fluid. The conditions required for extraction involves critical pressure above 74 bars and critical temperature above 31 ˚C. As the superficial solvent, CO2 is used in a fluid form to permit selective extraction of different components by varying temperature and pressure. For instance, the extraction of volatile oils from a plant can be achieved by using a low pressure of about 100 bars whereas phospholipids can be extracted by adding ethanol to the solvent.
flow chart of supercritical CO2 extraction process

The extraction methodology of using supercritical CO2 fluid allows for separation and collection of a different range of constituents components during a single extraction. It ensures that assembly of light essential oils is separated from other important heavier lipids and its constituents. This process guarantees the extraction of an unaltered, consistent, clean and flexible product.

Features of Supercritical CO2 Fluid Extraction

Supercritical CO2 fluid extraction, as a new process for extraction technology, has many advanced features, meanwhile, has some disadvantages as well.

Advantages of supercritical CO2 fluid extraction

Use of CO2 as the preferred solvent is because of its ability to create a quality, clean and pure oil that is safe for consumption with limited post processing. The use of other toxic solvents may require additional hours to remove the trapped solvents in the oil after extraction. Besides, most industries understand that the use of CO2 guarantees highly efficient commercial processing.

The extraction is based on diffusion, a process where fluid CO2 is required to diffuse into the matrix to dissolve the extracted material and in turn cause a flow out of the matrix into the solvent. The extracted material is dissolved and released much faster in supercritical fluids than it does in liquids. Supercritical fluids have negligible viscosities and minimal surface tension compared to that exhibited in liquids. These properties enable the supercritical solvent to penetrate more into the matrix that is usually inaccessible to liquids.

Therefore, the use of superficial fluid ensures the extraction occurs much faster. Use of the supercritical CO2 solvent is suitable to use in the regular separation systems that separate individual constituents during the extraction process for its tenability, efficiency, and affordability. Also, the use of CO2 supercritical fluid does not only separate constituent components, but it also prolongs its shelf life. The Sub-critical Biological Extraction Technology also has the ability to extract contituent component from the raw materials and prolong its shelf life.

Disadvantage of supercritical CO2 fluid extraction

As supercritical CO fluid extraction process needs high pressure for optimal efficiency, which inevitably cause strict requirements for the extraction equipment. So, it’s really hard to choose the best extraction equipment for supercritical CO2 fluid extraction, and the cost and quality for extraction equipment is also high. Besides, supercritical CO2 fluid extraction is not suitable for large scale production as present. For most oil manufacturers, supercritical CO2 fluid extraction needs adequate financial support when investing on it.

What's the Best Extraction Method?

Choosing the seed oil extraction methods not only rely on one factor, but should take the comprehensive factors into considerations, such as the raw material properties, the investment capitals, the production capacity and more. If you desire for an optimal plan for your extraction needs, please contact us, we will never let you down, just tell us your needs!

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