There are 3 different types of CBD extraction methods the CO2 extraction method, steam distillation and solvent extraction. There are pros and cons for both and below we will go into more detail about each method.
Carbon Dioxide (CO2) Extraction
Using supercritical carbon dioxide to separate the CBD oil from the plant material, is how CO2 extraction except it has a lot more steps than that. “supercritical” also sometimes referred to as Supercritical Fluid Extraction is where CO2 containing properties of both a liquid and a gas state. During CO2 extraction, a series of pressurized chambers and pumps are used to expose CO2 to high pressure and very low temperatures, resulting in an extracted oil containing high amount of CBD.
- One chamber holds pressurized CO2, whilst the second chamber will be pressurized whilst holding the hemp plant, this is the start of the extraction.
- The CO2 is then pumped from the first to the second chamber. The oil will separate from the plant material as the presence of the supercritical CO2 will break down the hemp in the chamber.
- The CO2 and oil will be pumped into a third chamber, to which then the gas will evaporate, which will leave an extract of pure CBD oil behind.
CO2 extraction is the safest and the most efficient way to extract CBD as it can extract as much as 92% of CBD however the specialized machinery is very expensive, but it is the most preferred way of extracting CBD. Another reason to why this is the most preferred way is that manufacturers can simply adjust the ratio of solvent and pressure to achieve the desired concentration of CBD.
In this method, steam causes the CBD oil to separate from the hemp plant. With an inlet and an outlet, the hemp plant is contained in a glass flask. The outlet connects to a condenser tube whilst the inlet connects to another glass container, beneath the plant flask, and contains water that is set to boil.
- The steam travels upwards into the plant flask, as the water heats up, separating the oil vapours that contain CBD.
- In a tube the vapours are captured which condenses them into oil and water.
- The oil and water mixture are distilled to extract the CBD oil from the water, once collected.
The steam distillation method has been used to extract essential oils for centuries, and has truly been tried and is true however its less preferred than CO2 extraction due to its inefficiency. Also, this method uses significantly larger amounts of hemp plant, and its more difficult to extract exact amounts of CBD concentration. Also is the steam gets too hot, it can damage the extract and alter the chemical properties of the cannabinoids it contains.
This CBD extraction method is similar to steam distillation however instead of using water it uses solvents instead to separate the CBD oil from the plant material. This creates a mixture of CBD oil with solvents. The solvent then evaporates, leaving pure CBD oil. Hydrocarbons or natural solvents are what this method normally uses. Solvent extraction is more efficient and cheaper than steam distillation however, the solvents used in hydrocarbon extraction, such as butane, propane and petroleum create a great concern. As the solvent residue if not fully eliminated in the evaporation step can increase one’s risk of cancer.
However, to avoid the risk of toxic residue, natural solvents such as olive oil or ethanol can be used for the extraction. These solvents are just as effective but remove the risk of toxin residue. However, chlorophyll may also be extracted when using natural solvents which can result in an unpleasant taste. The main problem with natural solvents is that they don’t evaporate very well, which means the CBD extract contains lower concentration of CBD than any other method.
So, what is the best extraction method for CBD oil?
So now you’ve read about the different CBD extraction methods, which do you think is best? We personally at CBD Pharm recommend CO2 extraction, as it is the safest, most efficient and gives the highest concentration of CBD, resulting the best quality product. Also we at CBD Pharm personally use CO2 extraction meaning our customers get the safest and best quality product. CBD extraction methods are not recommended to be used at home.