In the hemp and cannabis oil industry, there are three main ways to extract oil: ethanol extraction, hydrocarbon (butane) extraction, and CO2 extraction. This blog contains highlights from the methods used for all.
Ethanol extraction in the cannabis and hemp industry
Ethanol is a main ingredient in items such as liquor, fuel, and is considered to be a “universal solvent”. Within the cannabis and hemp oil extraction industry, ethanol is seen as the more efficient way to extract oil from your cannabis plants for products.
The process starts with soaking the plant in pre-chilled ethanol, which results in a solution that has separated the oil from the biomass. After, the solution is then filtered, and the ethanol is purged from the extract. You then get into winterization, which is the process of removing the impurities like plant lipids, chlorophyll, waxes, and fats from the oil. Having the oil chilled allows these impurities to be removed as they will be frozen, which creates crystals which will be caught in filtration.
With room temperature ethanol extraction, it tends to extract more plant lipids, chlorophyll, waxes, and fats than the cryogenic techniques, which further requires additional post-processing to remove.
Both room temperature, or cryogenic ethanol extraction methods, are commonly used as they allow for the retention of cannabinoid acid forms that can be leveraged to manufacture shatters, THCA crystals, or THCA-rich oral formulations.
Do you want to learn more about the equipment required for ethanol extraction? You can read more here.
Hydrocarbon butane extraction in the cannabis and hemp industry
Hydrocarbon extraction, involving Butane extraction, is another way to remove any undesirable matter from the oil extraction process. Butane is a non-polar liquified gas that has a low boiling point. It is effective in extracting because it is a low-pressure system.
The cold Butane is released, then slowly washes over the plant, dissolving the cannabinoids and terpenes from the cannabis. Once it is washed, you can collect the solution either directly, or have the solution go through a dewaxing process before retrieving the final product.
Although Butane is an effective way to extract the oil, it is not necessarily considered the safest way. It is a flammable solvent; so you need to take extra precautions when using this process. This extraction method requires you to ensure the machine that is being used is approved by safety standards for use at your location, and for it to pass any safety and hazard inspections.
You need to take into consideration the volume of product, the size of the location where the process is taking place, and the country’s safety standards in which you are located. In recent years, as demands increased, so has the number of explosions and fires. The butane residue can be toxic for consumption if not fully evaporated from the oil before consumption.
CO2 extraction in the cannabis and hemp industry
CO2 Extraction is the third process that can be used for cannabis oil extraction. This process requires pressurized force of carbon dioxide gas at an optimum temperature in the extractor chamber.
The CO2 interacts with the cannabis, and then dissolves the cannabinoid matter that it contains. It then carries the oil particles to a separator, where the pressure is then lowered and the CO2 and cannabis oil separate. The CO2 rises and the oil, and waxes are then collected in another container.
With CO2 extraction, a winterization process should follow where the extracted crude oil is mixed with ethanol and brought to -20C or lower temperatures to crystalize the undesirable material such as fats, lipids, waxes etc. Those solids can then be captured by a filter to produce a ‘winterized oil’. Although it is a time-consuming process, it is necessary to get the pure forms of the oil.
What does all of this mean for you?
With the three different processes, and most companies choosing their preferred method for different reasons, ethanol extraction is typically the most chosen method because it is a safe and efficient way of extracting hemp and cannabis oil on a large, industrial scale.
It is a polar solvent that binds to the cannabinoids, terpenes, but also water-soluble compounds that are undesirable, and chlorophylls. The chilled ethanol can largely overcome the polarity issue and bypass the chlorophyll, lipid, and other unwanted material. It is cost-effective at a higher volume.
There are multiple ways to extract cannabis and hemp oil in safe and efficient ways, but ethanol extraction is usually the best way for large scale extraction that is both safe and efficient. It allows the extraction with a low toxicity.
Do you have any questions about cannabis and hemp oil extraction methods? Maratek is a market leader in professionally-engineered extraction technologies. Contact us today. Our team of cannabis and hemp extraction experts would love to answer your questions.