CBD Extraction Methods
Cannabidiol (CBD) has been found to provide an array of therapeutic benefits and researchers have discovered safe and effective ways to extract CBD from hemp. The method used to extract CBD has a large impact on the quality of the final product; therefore, it is important to learn the different methods of CBD extraction.
The purpose of CBD extraction is to collect the compound in a highly concentrated form and make it suitable for human consumption. Extracting CBD begins with a CBD-rich plant, such as hemp. Hemp has a natural abundance of the CBD compound and contains low levels of the intoxicating THC compound. For this reason, hemp is considered an ideal plant for CBD extraction. Hemp-derived CBD is legal in all fifty states and you do not need a medical card to purchase hemp-derived CBD products.
There are numerous ways to extract CBD from hemp; here we outline the most popular (and safe) methods.
CO2 Extraction
CO2 extraction is the safest and cleanest method of CBD extraction and is therefore considered by most to be the standard method.
CO2 is a safe food additive and is used to carbonate soft drinks and remove caffeine from coffee beans to make decaffeinated coffee. CO2 is also used as an extraction solvent when producing essential oils.
CO2 extraction can be supercritical, subcritical, or mid-critical. These terms refer to what condition the CO2 is placed under during extraction. Supercritical CO2 extraction tends to be the more popular method as it results in a pure product.
Supercritical CO2 Extraction
At standard pressure and temperature, CO2 typically behaves like a gas. CO2 gas can be converted into a liquid by introducing it to a temperature below -69 degrees Fahrenheit and a pressure over 75 pounds per square inch (psi). This liquid stage is the starting point for CO2 extraction.
During supercritical CO2 extraction, the temperature and pressure of the liquid CO2 are increased until the liquid becomes supercritical. In this state, the CO2 has the properties of both a gas and a liquid. Supercritical CO2 can fill a container like gas and maintain density like a liquid. In a supercritical state, CO2 is ideal for chemical extraction because it won’t denature or damage the product.
To extract CBD from the hemp plant, the supercritical CO2 is passed through hemp in an extractor. The CO2 pulls essential trichome and terpene oils from the plant. Remember, trichomes secrete a sticky resin that contains essential cannabinoids.
The solution then gets passed through a separator and is broken down into individual parts. The trichome and terpene oils are sent to a collection container and the supercritical CO2 goes through a condenser to be turned back into a liquid.
Supercritical CO2 extraction is the most commonly used method by reputable manufacturers. While expensive, this method results in a safe and pure CBD extraction.
Solvent Extraction
CBD can also be extracted by using a solvent. Ethanol, low-grade alcohol, and butane are among the most common substances used in solvent extraction.
During this method, the liquid is added to the plant material to strip away the cannabinoids from the plant material. Once there are enough cannabinoids in liquid form, the liquid is heated to evaporate the material to a base oil.
Although a straightforward process, solvent extraction can be dangerous and potentially harmful. Depending on the solvent used, this form of extraction may produce an oil that contains chlorophyll or other harmful contaminants including residual chemicals. Certain solvents also destroy plant waxes that are considered to provide additional benefit.
It is not recommended to try this method at home, as solvents such as butane and ethanol are highly flammable.
Olive Oil Extraction
Olive oil extraction is another possible method of extraction; however, it is not a viable option for larger companies as it is labor intensive and only produces a small yield of product.
During this method, the decarboxylated plant material is added to olive oil and heated for several hours. This process should result in the extraction of cannabinoids. CBD infused olive oil is perishable and should be stored in a cool, dark place.
CBD Extraction Methods
Knowing how CBD is extracted from the hemp plant is just as important as knowing where the hemp plant came from. Both factors determine the quality of the final CBD product. Learn more about sourcing from a reputable manufacturer in the Ultimate Guide.
As a reminder, a CBD manufacturer should always provide the method of CBD extraction, if not in the content than upon inquiry.