In an industry described as being akin to the ‘Wild West’ due to the lack of regulation, it pays to learn and understand as much as you can about marijuana. One of the most important considerations one must make when searching for a cannabis brand is the method of extraction it uses.
Companies of a dubious reputation potentially cut corners and utilize chemical solvents such as lighter fluid (butane) and hexane. Aside from cheating customers out of valuable terpenes, chemical solvent extraction results in a product with possibly harmful residues. Do you feel comfortable ingesting yet more chemicals?
If the answer is “no,” you need to purchase CBD and THC from brands that use CO2 extraction only! This process kills harmful bacteria and ensures more terpenes and cannabinoids end up in the CBD product.
The process is becoming a popular one, and science backs it. A study by Jin et al., published in the March 2010 edition of Natural Product Communications, looked at supercritical CO2 extraction of a type of Japanese Cypress. The research team was able to determine the essential oil composition of the leaves and trunks of the tree.
What Is CO2 Extraction?
CO2 extraction uses pressurized carbon dioxide to take as many desirable cannabinoids from a marijuana or hemp plant as possible. It involves taking out the plant’s essential waxes, cannabinoids, and terpenes. In the end, CO2 oil is a healthy-looking amber-colored oil which you can use as a tincture or vaporize.
Manufacturers use carbon dioxide because it is a versatile, ‘tunable’ solvent. It acts as a solvent at a specific temperature and pressure range. However, it doesn’t have the dangers associated with solvents. As a result, consumers benefit from a premium-quality, clean oil with no toxic by-products.
Did you know that CO2 extraction is a standard extraction method in the herbal supplement and food industries? If you drink decaffeinated coffee, for example, you are already using a product that relies on carbon dioxide extraction to remove caffeine from coffee beans. Also, the gas is an extraction solvent in essential oil production.
These companies realized that conventional processes for extracting different components from food products had limitations regarding wastefulness, flammability, and solvent toxicity. Before the use of supercritical CO2 extraction, brands relied on solvents such as ethyl acetate, methylene chloride, and trichloroethane for decaffeination!
What Is CO2 Supercritical Extraction?
Although there are other methods, supercritical CO2 extraction is widely regarded as the industry’s gold standard. Carbon dioxide has the most reliable link with the process which is known as supercritical fluid extraction. It is the process of using supercritical fluids to separate one component from another. CO2 is the most commonly used fluid in this process, although it is occasionally modified by a co-solvent such as methanol or ethanol.
Scientists among you know that carbon dioxide presents as a gas at standard pressure and temperature. Supercritical CO2, on the other hand, is the fluid state of the gas, which takes place above its critical pressure and temperature.
CO2’s Supercritical Region
Here is a quick step-by-step guide to supercritical CO2 extraction:
- The extractor takes CO2 in its gaseous form and runs it through a chamber. At this stage, it is subjected to heightened pressure and temperature as low as -70 degrees Fahrenheit.
- The gas changes into a fluid.
- It is in this state that CO2 showcases its unique properties once reheated and pressurized. A supercritical fluid has properties between a gas and a liquid. For example, it maintains the density of a liquid while filling space like a gas.
- The special fluid passes through a chamber that contains the raw hemp or marijuana material.
- The fluid passes through the raw material and dissolves the trichomes’ membranes. As a result, the process captures a significant proportion of the active compounds.
According to the February 2010 edition of Chemical Engineering, CO2 has a critical temperature of approximately 89.78 degrees Fahrenheit. Its critical pressure is 73.8 bars, the equivalent of 7.38 million Pascals, or 1,070 pounds per square inch.
A study by Peach and Eastoe, published in the Beilstein Journal of Organic Chemistry in August 2014, discussed supercritical CO2, describing it as “a solvent like no other.” The study looked at how supercritical CO2 could become a major aspect of a movement towards green chemistry.
In case you were wondering, there is also subcritical CO2 extraction. It isn’t as common a method as its supercritical cousin, mainly because it takes more time and produces less material. Subcritical is a similar process to supercritical, except it requires lower pressure and a lower temperature.
While it is a longer and less efficient process, it provides a high-quality product because it retains terpenes, cannabinoids, and essential oils.
A supercritical system produces a thicker substance with a consistency akin to that of peanut butter. This is because the higher pressures and temperatures extract larger molecules, including waxes, chlorophyll, and omega-3 and 6 lipids. Then, the ‘winterization’ process removes these substances, which leaves behind the cannabinoid oil only.
In contrast, subcritical extraction produces a material with a consistency similar to molasses.
Benefits of CO2 Extraction
One of the primary benefits of using a cannabis extract from CO2 extraction is its status as a ‘green solvent.’ Whether it is CBD extraction or THC extraction, the use of carbon dioxide provides a cleaner and healthier product. We produce CO2 naturally as part of the breathing process when we exhale.
Unlike solvents such as butane, CO2 extraction contains no nasty chemical residues. It is also recyclable and cost-effective.
Supercritical CO2 extraction has unique properties.
- It is non-flammable, inert, and non-toxic.
- The process has moderate critical constants.
- You can fine-tune the solvation strength by adjusting the liquid’s density.
- As carbon dioxide leaves a low level of residue compared to other solvents, you should find large quantities in pure form.
- The critical temperature of CO2 is near-ambient, which means it is an ideal solvent for temperature-sensitive materials.
The Entourage Effect
While a clean product is essential, perhaps the biggest benefit of CO2 extraction is its capacity to extract dozens of cannabinoids and terpenes. The marijuana plant has over 110 identified cannabinoids and hundreds of terpenes and flavonoids. Even though THC and CBD both have an array of purported benefits, an increasing number of experts now believe that weed and hemp’s real ‘magic’ involves a combination of its terpenes and cannabinoids.
Cannabinoids such as cannabinol (CBN) and cannabigerol (CBG) are not as abundant as CBD and THC, but potentially have health benefits of their own. For example, CBG could have neuroprotective properties. Meanwhile, CBN has a link with a significant decrease in pain levels.
Then there is the small matter of terpenes. For example, alpha-pinene could counteract memory loss associated with THC. Myrcene may reduce resistance in the blood-brain barrier and lead to a more comfortable passage of helpful chemicals in the body.
The list goes on and on. The entourage effect suggests that cannabinoids and terpenes work better together than in isolation. While a high-quality THC or CBD isolate has its uses, a full-spectrum product is potentially a better bet.
Although ‘CO2 oil’ is the best around, don’t be shocked to learn that low-cost cannabis you desire does not involve CO2 extraction.
CO2 Extraction Equipment
There is no getting around the fact that supercritical CO2 extraction is expensive. Therefore, companies that invest in it usually provide the best quality hemp and marijuana oils.
We have found a CO2 extraction machine that costs $445,000, and there are certainly more expensive models. The equipment in question is the Apeks Supercritical CO2 system. It processes up to 200 pounds of dried material each day – an incredible amount. The system will tackle the biggest workloads in the industry, and is perfect for gigantic manufacturers. Its features include:
- The ability to perform supercritical and subcritical extractions.
- Full automation.
- An equipped carbon dioxide storage tank.
The Hi-Flo FX2 20L 5K machine is another behemoth and costs approximately $175,000. It can process up to 107-pounds of biomass each day and offers a maximum of 5,000 psi, not to mention rapid change-over. While the capacity isn’t the biggest in the industry, it is undoubtedly not suitable unless your operation is massive.
The brand also has a 3x2000L model with a load capacity of 3,000 pounds! This particular machine has an extraction run time of between 4.5 and 6 hours, and like the smaller model, offers an average of 15% yield.
If you are on a tight budget, the Super C Extractor is available for ‘just’ $4,000. It looks like a doll-house compared to the giants of the market, but it is perfect for small-scale businesses. It can process an ounce of material at a time with a maximum pressure of 4,500 psi
Final Thoughts on CO2 Extraction
Ultimately, when you are purchasing hemp oil and cannabis oil, it is best to save your money and wait for products where supercritical CO2 extraction is involved. First and foremost, it increases the likelihood of getting a ‘clean’ and healthy product due to the lack of harmful chemical residue.
Secondly, such products typically contain a full-spectrum of cannabinoids and terpenes. An increasing number of experts in the field recommend such products and believe they are superior to isolates. Finally, supercritical CO2 extraction equipment is expensive, so you know companies that use it are serious about providing the best products around.
While CO2 extracted marijuana, oil is ultimately more expensive, you unquestionably get what you pay for.