Carbon Dioxide Extraction or CO2 extraction is a very safe and common extraction method that is used to make various foods, products and is quickly becoming a preferred extraction method amongst large commercial operations in the recreational and medical cannabis industries as well as the hemp industry for the quality extraction of cannabis oil and quality CBD extracts. CO2 Extraction is an environmentally friendly, safer and cleaner extraction method than that of extractions using harsh chemical solvents such as butane and hexane. CO2 extraction provides a more consistent product that is clean and much more flavorful than other forms of solvent based extraction as well.
CO2 is a gas at standard temperatures and pressures but when it's heated to 87.98 degrees (critical temperature) with 1,071 PSI (critical pressure) or higher, CO2 then has the properties of both a gas and a liquid, which is known as a supercritical liquid. Supercritical carbon dioxide extraction happens when supercritical liquids pass through porous solids and dissolve various materials, this is why CO2 is considered an ideal solvent. Supercritical CO2 can be dialed in accordingly to provide the maximum output of cannabidiol dependent on the cannabis material used while keeping undesirable compounds, fats and lipids out of the final extraction product assuming that they are applying a fractionation process, otherwise the end product will need to be winterized to remove fats, oils and waxes to deliver a clean and safe extract.
Subcritical CO2 extraction is essentially the same process, but supercritical extraction happens at higher temperatures and pressures which means that during subcritical CO2 extraction, the carbon dioxide stays in a liquid state providing the extractor with a completely different cannabis extract than that of a supercritical CO2 extraction. However, because subcritical CO2 extraction happens at lower temperatures, things such as bacteria, mold and contaminants that could be problematic for consumers with compromised immune systems are not killed off like they would be in a supercritical CO2 extraction.
Supercritical CO2 extraction can produce around a 10% cannabis oil return based on trim weight, but if other resins and waxes are added in depending on the applications, yields can grow to around 17 to 25 percent. Supercritical carbon dioxide extraction systems are extremely beneficial because they can be used for both supercritical and subcritical extraction processes, whereas it doesn't work the other way around. This then allows you to perform various extraction processes on the same amount of material with less additional processing measures, providing you with the most flexibility when it comes to performing CO2 extraction.