Your Guide to Ethanol Extraction
Posted on August 20, 2020 by Paige Pesko
Because of the controversial nature of cannabis-based products, CBD has developed an air of mystery. People often imagine back-alley operations or giant vats of steaming materials stirred by strangers in hazmat suits, when in actuality the process of making CBD is a matter of simple science. It’s time we removed the mystery of CBD by breaking down the process by which it’s made. This is your guide to ethanol extraction.
What Is Extraction With Ethanol?
Extraction is one of the most important stages of processing hemp into CBD oil. In it, the cannabinoids are “extracted” from the hemp plant and filtered for the oil. There are multiple solvents used in extracting cannabinoids, including CO2, olive oil, butane, and propane, but as we mentioned in a previous blog, ethanol is usually the preferred solvent.
Ethanol, also known as ethyl alcohol, is a natural compound (chemical formula C2H5OH) that is produced from plant fermentation. It is used for a wide variety of commercial and scientific uses from hair care and beauty products to fuel, but it is probably most known as the substance that gives beer, wine, and spirits their intoxicating effect.
When hemp is soaked in ethanol, the ethanol effectively extracts not only the cannabinoids but also other oil-soluble compounds from the hemp. It is the solution most effective for creating full-spectrum CBD products. This process isn’t as simple as boiling the hemp in the ethanol like you would boil a bag of tea, though. It requires preparation, precise temperature adjustments, and proper filtration.
The Extraction Process
In scientific terms, decarboxylation is the process of removing a carboxylic acid from a substance. In the world of cannabis-based products, many people think of this product in terms of THC, the substance in cannabis plants that produces a “high.” For cannabis products containing THC, decarboxylation is necessary for the THC to have its effect. While CBD oils as a rule don’t contain THC, the oils also have to go through decarboxylation before they go through the extraction process. Simply put, decarboxylation involves heating up the plants to convert the cannabidiolic acid into cannabidiol, or CBD. This will allow the body to experience the benefits of CBD when a person takes it by means of a method other than inhalation.
After the plant material is decarboxylated, it is ready to be soaked in the ethanol solution. As with other extraction methods, solvents must be cooled to specific temperatures to achieve maximum and consistent product quality. Refrigeration units are often attached to systems to assure that the same temperature is reached and maintained every time. This will separate the cannabinoids and other plant substances and fats.
Even after the cannabinoids are extracted, you have to further separate the substances. This is when a process called winterization comes in. Winterization involves heating and then freezing the substance to separate lipids and waxes from the cannabinoids and plant compounds. Winterization removes these things in a way that minimizes CBD loss. It also ensures that any remaining THC is completely removed. This is especially important for CBD oils since THC content is a factor that determines whether or not a product is legal.
Although waxes and lipids have been removed, at this point in the process, there is still plant matter such as chlorophyll to contend with. Chlorophyll, a natural pigment existing in plant cells, will not make your product less effective or cause it to become toxic. However, it will make your CBD oils taste bitter and grassy, so most people choose to remove it.
Once the oil is filtered, it has to undergo a final separation from the ethanol and removed plant matter. This process is called short-path distillation. It involves taking the crude oil and putting it in a vacuum called an evaporation chamber. After the material is distilled, it is separated into distillate which contains the CBD and residue which contains any plant products or alcohol. After the CBD oil is collected, the residue is sent through a process in which the ethanol is removed, heated, and cooled to be reused in future processes.
This step is optional, but it helps achieve much higher qualities of CBD oil. After you have reached the point of having a completely clear distillate, you will mix the CBD with pentane or heptane. They will be chilled, agitated, then heated again to close to boiling. In time, the distillate will be dissolved, and after cooling the mixture again, CBD crystals will begin to grow. These crystals can be removed and rinsed again in cold pentane, then dried. These crystals can be consumed very similarly to CBD oil when dissolved and have a 98 percent purity rate.
Although ethanol is safer than other solvents like butane and propane, it’s still a flammable substance. Pentane is also highly flammable if you are opting to put your products through crystallization. For that reason, fire safety is extremely important when performing ethanol extraction. Be sure your employees are trained in how to prevent a fire and how to respond to one. Ethanol fires, like gasoline fires, cannot be put out with water, so be sure there are enough fire extinguishers available.
Wherever you’re working in the cannabis industry, you have to be wary of dust and other pesticides from cannabis plants. In some places, an increased rate of respiratory conditions has been reported among workers in cannabis production facilities. Ethanol fumes can also potentially be dangerous when inhaled, as can pentane. Consider having employees wear facial protection, at least while handling extracted plant matter or during the crystallization phase. Facilities should also be well ventilated to improve air quality.
It’s our sincerest hope that our guide to ethanol extraction has removed some of the mystery from the entire CBD production. And while we’re at it, let us take some of the mystery out of the process of choosing equipment for ethanol extraction. Our cannabis extraction equipment will get the job done, and with its stainless steel exterior, you can be sure it will last a long time.