There are many ways to extract cannabinoids, terpenes, and other desirable compounds from cannabis. Today’s most commonly used methods of extraction involve passing a solvent, such as supercritical CO2, butane, or ethanol, over or through cannabis, separating beneficial oils from plant matter.
Used as afluid solvent in the extraction of compounds from cannabis, supercritical CO2 produces a purer and cleaner end product than most other solvents. The purer form of extract produced is due to CO2 rendering no residual solvent material left behind in the extract, thus requiring no purge of solvent contaminate after the extraction process has completed.
The production of cannabis extracts using supercritical CO2 is considered the safest way to produce extract. Unlike combustible solvents, such as butane and ethanol, the CO2 extraction process poses no threat from fire or explosion. Also, since the solvent properties of the medium depends on the temperature and pressure of the system, sCO2 can be tuned to favor the extraction of certain cannabinoids and terpenes, which is another main attraction
Although butane has garnered a bad rap in recent years, due in large part to being highly flammable, its use as a solvent to extract cannabis compounds is considered by many to be the best. Experienced producers of cannabis extracts tout the benefits of using butane because of its ability to solubilize cannabinoids, as well as a wide spectrum of lighter, more volatile terpene compounds into the concentrate.
Due to butane’s low boiling point, purging the concentrate of any residual solvent is relatively easy. When properly used and purged of any remaining butane, these extracts can bepotent and reminiscent of the scent and physiological effects attributed to the cannabis cultivar. Butane has the ability to extract highly desirable compounds from cannabis without co-extracting undesirable molecules such as chlorophyll and plant metabolites.
The abundant and readily available nature of butane makes this solvent a wallet-friendly option when considering cannabis extraction.
Alcohol extraction of beneficial plant compounds has been used for centuries in the form of tinctures. Prior to prohibition, ethanol tinctures of various plant extracts, including cannabis, were widely used for many different ailments and included in the Pharmacopeia.
When used at freezing temperatures, ethanol can provide some selectivity for extracting specific terpenes and cannabinoids from cannabis, while leaving other undesirable molecules like waxes and lipids behind.
With today’s many choices for cannabis compound extractions, these three solvents all have the ability to produce high quality concentrates with many beneficial properties.