Supercritical Fluid CO2 Extraction (SFE-CO2) is a process in which the objective compound is extracted and separated from its material using supercritical carbon dioxide as solvent. The supercritical state of a matter means that both its temperature and pressure are higher than the critical temperature and the critical pressure respectively. SFE-CO2 is based on the large difference in dissolubility of carbon dioxide at different temperature and/or pressure. As a result, we can control conveniently the selectivity and completeness of extraction by changing the temperature and pressure of carbon dioxide.
The unique properties of SFE were observed more than a century ago, but only in the last three decades has SFE evolved as a novel separation technique。 Honea’s research of Supercritical fluid CO2 extraction can be dated back to 1980’s; we have more than three decade experience of Supercritical fluid CO2 extraction。 We are the first company to realize industrial mass production of Supercritical Fluid CO2 extraction in <st1:country-region w:st="on">China, we have established long term partnership with institutes and company around the world。
SFE is used in a variety of products including natural foods and flavours, pharmaceuticals nutraceuticals, polymers, chemicals, and equipmentcleaning6。 The most common use today is the decaffeination of extraction of essential oils, oleoresins, flavours and aromas from spices and botanicals。 SFE can also remove residual organic solvents or impurities like pesticides from final active compounds or food ingredients。
A supercritical fluid (SCF) is made from a gas or a liquid, nota solid。 When a gas or liquid is compressed (under pressure) and heated past its critical point, it enters a phase called the “supercritical phase” and is referred to as a “supercritical fluid” (SCF)。 The critical temperature (Tc) and pressure (Pc) at which this happens are unique to each pure substance。 In the supercritical state, the "fluid" takes the properties of both gas and liquid。
The whole SFE-CO2 process combines extraction, separation and concentration, the extraction period is short, the process of extract and separation are taken place at the same time, which ensure the bio-availability and the quality of the active compounds, there is no solvent and pesticide residue, heavy metal level is low, the Supercritical fluid CO2 extraction is environmental friendly。
Up to now, Supercritical fluid CO2 extraction achieve success in the following areas:
cosmetics function ingredient
food additive and dietary supplement
Flavours, fragrances, aromas and perfumes
Food colours from botanicals
Antioxidants from plant materials
eliminate solvent and pesticide residue
Antibacterial agent from Magnolia Bark
decolorized and deodorized product
Special separation, purification and refining.
Extraction of a specific group of compounds is the most common use for supercritical fluids。 The major process parameters are temperature, pressure and flow rate。 The three primary steps are extraction, separation, and CO2 recovery。 The plant, usually fine powder, is charged into the extractor, along with the CO2 which is fed into the extractor through a high-pressure pump(>74bar) and CO2 heater(>31℃)。 The extract laden CO2 is sent to a separator(s) via a pressure reduction valve。 At reduced temperature and pressure, the extract precipitates in the separator while the CO2, free of extract, is recycled to the CO2 main tank。