The term supercritical refers to using gases that have been compressed past their “critical point”. CO2 oil is often used in cannabis extraction because the critical point is at 90°F. Some believe that this temperature preserves the delicate cannabinoids and terpenes from the plant. That’s why this is one of the more commonly used supercritical extraction methods. CO2 is also nonpolar which makes it more similar to commonly used hydrocarbon extraction solutions butane and hexane.
A supercritical fluid can diffuse through solids and dissolved compounds. It behaves both like a gas and a liquid. When the pressure changes, the dissolution patterns of the supercritical CO2 change. The plant matter is run through a varying number of columns. There are generally three separate pressure phases used when extracting terpenes and cannabinoids using supercritical CO2.
The first phase that the plant matter and CO2 move through is the extraction process. Then they will move through a column to separate them. The last phase allows the chemist to remove the CO2 extraction. Each of these phases requires their own specific temperatures and pressures. Some studies have shown that this process preserves a more stable extraction than extracts made using hydrocarbons like butane.
Many extraction experts have been keeping their methods to themselves. In the current state of cannabis many growers, breeders, and extractors view their methods as proprietary. There is a mixed bag of professionals out there. Some are looking to share their methods with the world so that patients can have a safe product. Others are looking at the budding industry as more of a Silicon Valley which is bringing an air of cloak and dagger to the party.
Luckily Terpenes and Testing is an advocate for everyone receiving and educational breakdown of cannabis science. We will be hosting a FREE live webinar on April 27 from 9 AM to 1 PM. We’re already halfway to sold out, to secure your spot follow the link below.