Extraction and fractionation is the broadest application of liquid or supercritical CO2 and many commercial processes already exist at large scale. The equipment at Suprex allows trials to be carried out on as little as 5g of material through to intermediate laboratory and pilot scale. Extraction can be carried out using CO2 in a liquid or supercritical state and the choice largely depends on the solubility of the molecules to be extracted.



Liquid CO2 is significantly less polar than supercritical CO2 and is more applicable to small, non-polar molecules. In the supercritical state, CO2 is a highly tuneable solvent and the manipulation of temperature and pressure allows selective extraction of a wide range of molecules.

Suprex has expertise across a wide range of applications of the use of CO2 as a solvent including:

• Flavour and fragrance ingredients
• Waxes for cosmetic and personal care products
• Plant derived pharmaceutical and nutraceutical molecules
• Pigments from plants and algae
• Biosurfactants from fermentation processes

Supercritical CO2 has low surface tension and viscosity and therefore high mass transfer rates can be achieved, providing ideal conditions for extracting compounds with a high degree of recovery in a short period of time and with easy separation of products.

At Suprex extraction and fractionation is most commonly carried out with solid materials but Suprex has developed a number of novel methods to fractionate complex liquid mixtures that are completely scalable to multi-ton quantities.



Extraction and fractionation is normally carried out in a “closed loop” in which the CO2 is continuously recycled and the extracts collected by pressure reduction in a series of separators. This is the arrangement of the Suprex pilot plant.