In this method, plant material like flowers and trim are put into a container. Liquid solvent (usually butane, isopropyl alcohol, hexane, or ethanol) is run through the plant matter to strip it of cannabinoids and flavours and transfer them into the liquid. Then, the liquid is evaporated away from this mixture to leave only concentrated chemicals and flavours in the form of an oil. CBD extraction benefits of this method are many— it is the most simple, equipment-free, and inexpensive way to extract CBD, but not without some downsides. One concern is that solvents can leave traces of impurities in the finished CBD oil (meticulous processing methods and the right solvent can minimise this). Also, some liquid solvents remove chlorophyll from the plant along with cannabinoids and flavours, giving the finished oil a greener colour and more bitter taste.
Also, some liquid solvents remove chlorophyll from the plant along with cannabinoids and flavours, giving the finished oil a greener colour and more bitter taste.However, because these negative effects can usually be countered by adjusting specifics in the process, this remains the most common method for CBD extraction.
Carbon Dioxide (C02) is a unique molecule that can function as any state of matter— solid, liquid, or gas— depending on the pressure and temperature it is kept under. Because variables like pressure and temperature have to be kept very specific in a C02 extraction, this extraction method is usually done with a piece of equipment called a ‘closed-loop extractor’.
This machine has three chambers: the first chamber holds solid, pressurized C02 (commonly known as ‘dry ice’), the second chamber contains dry plant material and the third chamber separates the finished product.
When performing the extraction, the solid C02 from the first chamber is pumped into the second with the plant material. This second chamber is kept at a specific pressure and temperature which causes the C02 to behave more like a liquid (although it’s actually somewhere between a liquid and gas in this state, referred to as supercritical C02) so that it runs through the plant material and extracts chemicals and flavours, much like in the liquid solvent process. Then, the C02-cannabinoid mixture is pumped into a third chamber where it is kept at an even lower pressure and higher temperature so that the C02 gas rises to the top of the chamber while the oils containing chemicals and flavours from the plant material fall to the bottom to be collected for consumption. Ther