The cannabis industry keeps on expanding and extracts of cannabidiol (CBD) and tetrahydrocannabinol (THC) conquer the medical and recreational markets. The usage of the extraction is important, yet the way they proceeded is more vital. The form and further application of the extractions are highly dependent on the extraction method and equipment.
The entire process usually follows these basic steps:
Extraction – When people talk about how CBD products are made, they’re mainly talking about the specific extraction method. The most common methods to extract CBD oil use carbon dioxide, steam distillation, or hydrocarbon or natural solvents. There are pros and cons to each extraction method. While supercritical co2 extraction and ethanol extraction are the most popular extraction methods in the industry.
Winterization – The extract from the first step then needs to go through a process of purification to get rid of unwanted byproducts and contaminates. Winterization is the act of removing any unwanted fatty acids, plant materials, chlorophyll, cannabinoids, and terpenoids contained in your CBD extract. This is the process in which non-polar substances (such as hash oil) are dissolved into a polar substance (most commonly ethanol) at sub-zero temperatures. This forces waxes and lipids (fatty acids) from the crude extract to the top of the mixture – where they can be easily removed through the filtration process.
Solvent Recovery –As the extraction industry grows, so does the necessity of large-scale, efficient machinery. As the extraction industry has significantly scaled up over the years, the speed of solvent recovery has become one of the biggest bottlenecks in the process. The evaporation and condensation of solvents, such as ethanol, require a balanced amount of heat and cooling to make the recovery efficient and effective.The hemp and cannabis industry quickly turned to rotary evaporators, also known as a RotoVap. Basically, a RotoVap has a spinning flask that is in contact with heated water. As the ethanol evaporates it is passed through a condensing column and is recovered while your “crude” material remains in the flask.
Decarboxylation – At this point, we have a concentrated oil, but without the signature psychoactive effects. This is because a cannabinoid called THCA (tetrahydrocannabinolic acid) is still present in the mixture. THCA loses its acidic form and turns into THC, the beloved intoxicating compound, after the application of heat in a process called decarboxylation. Temperature and time are the causative factors in this process as THCA begins its transformation at 104 C / 220 F. The process itself entails the removal of carboxylic acid from the cannabinoid by using heat. With the carboxylic acid attached, the cannabinoid will be processed as any other greens. Freeing up the cannabinoid from the attached carboxylic acid allows it to freely interact with the nervous system and bind to cannabinoid receptors (CB1 and CB2) as a psychoactive compound with both medicinal and recreational properties.
Distillation – Finally, distillation! This is what we’ve been waiting for. This purification process utilizes heat, steam, and vacuum pressure to separate the chemical compounds within the concentrate so far to get to a concentrated cannabinoid distillate. At this stage, terpenes and flavonoids are extracted from the mixture, leaving behind the precious cannabinoids. This process requires careful monitoring of heat to reach the compounds’ specific boiling points. Being in a vacuum helps with controlling the temperature of the reaction, therefore minimizing the need for high heat to meet boiling points and potentially reducing the potency of the cannabis distillate. Slowly, the compounds are separated, and unwanted ones are discarded, leaving a refined collection of potent cannabinoids. Some processes require the mixture to undergo several rounds of distillation to reach optimal potency.
Crystallization –It is generally accepted that the purity of CBD distillate must be at least 80% in order to crystallize by itself. In fact, if this is something which you have noted happening to your CBD distillate of its own accord, chances are that the level of purity is above 85%. This is certainly not a bad thing! Below this level of concentration it is possible to crystalize your CBD distillate, but only through a thorough crystallization process utilizing the correct technology to regulate the temperature and ensuring the correct use of solvents. Crystallization (or recrystallization) is the most important method for purification of organic compounds. The process of removing impurities by crystallization involves dissolving a compound in an appropriate hot solvent, allowing the solution to cool and become saturated with the compound being purified, allowing it to crystallize out of the solution, isolating it by filtration, washing its surface with cold solvent to remove residual impurities, and drying. This is best done in a controlled chemistry laboratory, in a well-ventilated area. Note that this procedure has wide applications, including large scale commercial purification of sugar by crystallization of the raw sugar product which leaves impurities behind.
THC Remediation–THC remediation is the process of removing THC from a cannabis distillate. Obviously, if you’re extracting cannabis oil and making its concentration greater, then the relative volume of THC will increase. This can happen with both crude or distillate, Where CBD is legal, THC levels typically need to be less than 0.3%. In order to find a way to remediate THC, we have experimented with various methods and have found a way to help achieve the hemp and cannabis processor’s THC reduction goals. Although there are numerous techniques available, using some form of chromatography is the most common.