Cannabidiol (CBD) is a kind of natural compound peculiar to hemp or cannabis plant. Unlike delta-9-tetrahydrocannabinol (THC) that is the major active ingredient in hemp, CBD is not psychoactive. As scientific studies have confirmed that CBD may be helpful to relieve pain, anxiety and other symptoms, it has become more well-received in the health field. It is better to first extract CBD from raw plant material in order to obtain its full benefits.
What is CBD Extraction?
CBD extraction refers to the process of extracting CBD from hemp or cannabis plant and separating it from other components. There are various methods for extracting CBD from hemp or cannabis plant. It is necessary to learn the difference of these extraction methods due to they greatly influence the quality and purity of final products and even other components. There are primarily four methods for extracting cannabidiol.
1. Olive oil extraction
2. Butane and propane extraction
3. Ethanol (alcohol) extraction
4. Supercritical CO2 extraction
Olive Oil Extraction
Olive oil is used in this method. Firstly, the plant material should be decarboxylated for activating the chemicals inside it, which can be done by heating. After decarboxylation, mix the plant material with olive oil and heat them for several hours. Then CBD, terpenes and other components will get out of the plant and come into the olive oil. It is a simple extraction method that can be performed at home. But it is unsuitable for commercial use with weak CBD content.
Butane and Propane Extraction
Butane or propane is used as the solvent in this method. CBD can be dissolved and isolated by submerging the plant material in the solvent. Then the solvent with a low boiling point can be evaporated to leave behind crude CBD oil. It is generally regarded as the easiest and cheapest method of extraction, but it may destroy certain plant waxes and leave behind some harmful residues.
Ethanol (Alcohol) Extraction
In this method, the plant material mixes with the ethanol, which are capable of stripping the cannabinoids from the hemp plant. Then ethanol can be boiled away. It can be said that ethanol is the most commonly used solvent for extracting CBD because of its effectiveness. It can produce more cannabinoids as well as preserve more terpenes. Some people even consider that ethanol extraction is the best method for extracting CBD from hemp. But it can pull more chlorophyll from the plant. It is also a long purification process.
Supercritical CO2 Extraction
Supercritical CO2 extraction is known for producing a high quality product. It is regarded as a green extraction method compared to traditional organic solvents. This extraction method possesses a great number of benefits. For example, CO2 is non-toxic, non-inflammable and inert. Unlike other organic solvents, CO2 extraction contains less chemical residues. With the development of solvent recovery technology, it is recyclable and economical as well. It is also considered as an ideal solvent for temperature-sensitive materials. But this method is highly expensive as an industrial process and it requires expertise to perform correctly.