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How It Works: CBD Extraction via Supercritical CO2

How do we get CBD from hemp?

The raw materials and chemical precursors which comprise many pharmaceutical drugs originally come from plants. Bioactive compounds originating from plants are called alkaloids.  Once they are extracted, chemists develop processes that transform these plant-derived substances into biologically active drugs, fine-tuned for a specific purpose.  It can be difficult or impossible to ensure that a drug will have only one effect on the body however, and that fact is what makes many health-conscious individuals look outside of the traditional pharmaceutical industry for remedies that are more natural.

Enter cannabis; it is the true “traditional” medicine, as it was used for thousands of years before the word pharmacy was even invented. Nonetheless, even some cannabis-based medicines, like CBD oil or CBD-infused edibles, still must undergo an extraction process to be fully absorbed by the body.

There are several different methods of extraction including butane and ethanol based processes, but the best method, by every metric except for cost, is the use of pressurized carbon dioxide: supercritical CO2.

What is supercritical CO2 extraction?

Carbon dioxide extraction of essential compounds and oils is a very flexible process that involves the use of expensive equipment to extract specific compounds from raw plant material with absolutely no solvent leftover.

First, plant material is compressed at a low temperature.

Second, pressurized supercritical CO2 is forced through the plant mixture.

The variability of CO2 temperature and pressure is what makes this method so much more effective than other forms of extraction, because just a subtle change in temperature or pressure results in a drastic change in its density. During this step, the single desired compound is drawn out of the plant by the CO2 and collected in a reservoir.

Third, the CO2 evaporates back into a gas as the mixture is brought to room temperature, leaving behind only the desired compound and no solvents or residues of any kind.

At this point, the desired compound, in our case CBD, is extremely concentrated because it’s the only compound that was drawn out of the plant. In this state, it’s an oily crystal that is sometimes referred to as shatter because of its brittle nature. This can be dabbed as is, or formulated into any of the other common CBD products that many are familiar with, such as topicals or sublingual oils, and even edibles.

Every cannabinoid in cannabis has therapeutic value, including and especially CBD and THC. However, THC produces the high synonymous with marijuana, and therefore a strong stigma taints the medical value of cannabis because THC is the most abundant compound in the plant.

For this reason, many companies have begun to use supercritical CO2 extraction to produce THC-free CBD oil that is rich in CBD and other cannabinoids and terpenes without a single molecule of THC present in the final product.  This not only makes it legal in all 50 states, but it also removes any possible psychoactivity (the feeling of being high) and both permits and establishes extremely high standards for the quality of any cannabis-based extract, free of contaminants, toxins, or any other foreign substance that detracts from the potency of your medicine.