CO2-Based CBD Extraction Explained

CBD and the other cannabinoids and cannabis plants are key ingredients in everything from medicines to health and beauty products. But to get at those cannabinoids, they have to be extracted from plant material. How they are extracted depends on the processor’s preferred method. CO2-based extraction is one option.

CO2-based CBD extraction is solvent-based extraction. But rather than using a liquid solvent, like ethanol, CO2 is tapped instead. Subjecting plant material to CO2 forces all the cannabinoids, terpenes, and other compounds out of the leaves, stems, and flowers. But the process does not stop there. The resulting ‘crude oil’, as it is known in the industry, has to be further processed.

  1. Extracting CBD with CO2

CO2 extraction is a little bit different because it is based on heat and pressure rather than a chemical reaction. This is one of the reasons that CO2 extraction is considered cleaner and more pure. According to CedarStoneIndustry, a Houston company that manufactures CBD extraction equipment, this particular method of extraction is gaining popularity among cannabis processors.

Extraction begins by placing plant material in a specialized tank. The sealed tank is then heated and pressurized. Over the course of the extraction process, gradually building heat and pressure force cannabinoids, terpenes, lipids, and waxes out of the plant material. The plant material and crude oil are separated once extraction is complete.

CBD crude oil is not very usable as-is. In order to make it so, it has to be put through a process known as winterization. Finally, distillation allows processors to isolate certain cannabinoids and terpenes they might be interested in for a particular product formula.

  1. Crude Oil Winterization

The winterization process takes its name from the cold temperatures it involves. To winterize crude oil, the oil is first mixed with alcohol. After being thoroughly stirred to ensure proper blending, the mixture is placed in a freezer for 8 to 10 hours. This causes unwanted compounds, like lipids and waxes, to congeal. Those lipids and waxes can then be filtered out.

What remains is a mixture of alcohol and the desired cannabinoids and terpenes. To remove the alcohol, heat is applied. Because alcohol has a lower boiling point than both cannabinoids and terpenes, it can be removed through evaporation without harming the good stuff.

  1. CBD Distillation

The last step in the process is distillation. However, some processors prefer to decarboxylate their CBD oil prior to distillation. At any rate, distillation is accomplished through application of more heat. Once again, the goal is to evaporate and condense. Different cannabinoids and terpenes evaporate at different temperatures, so the application of heat at control temperatures allows for easy separation.

Bear in mind that there are more than a hundred cannabinoids in cannabis plants. There are also dozens of terpenes. CBD and THC are the most commonly utilized cannabinoids for medicinal and health and beauty needs. As for the terpenes, they are the oily compounds that give plants their unique odors.

The main goal of CO2-based extraction is to gain access to as many cannabinoids and terpenes as possible, and in the purest possible form. Other types of solvents are sometimes used instead. They include substances such as ethanol and olive oil. Though using CO2 involves a more expensive and time-consuming process, it is said to yield a better crude oil in the end.

Extracting cannabinoids and terpenes is big business. Between CBD, medical cannabis, and recreational marijuana consumption, processors are making good money extracting crude oil which can then go into manufacturing all sorts of products ranging from CBD oil to soaps and lotions.