Cannabidiol (CBD) can be extracted several ways, one of the most notable is CO2 Extraction. We break down the Pros and Cons of using CO2 over other methods. A cannabis concentrate made through CO2 extraction, which uses CO2 as a solvent to strip the cannabis plant of cannabinoids and terpenes into a concentrate. Learn more about CO2 oil from Leafly. CO2 extraction is by far the best method to produce full-spectrum CBD oils and leverage the entourage effect. How does it work and what are the benefits of using CO2 for extraction? Read on to find out!
CO2 Extraction of Cannabidiol (CBD) – Process and Why it’s Important
CBD products are becoming increasingly popular, leaving many consumers wondering where to start. While it’s true there are almost more options than you can count in the world of CBD today, there’s one important factor everyone should consider before buying and consuming a hemp product: How it’s made.
In terms of CBD products, how the hemp oil is extracted drastically impacts the final result. Although all methods are attempting to do the same thing – create a highly concentrated version of cannabinoid for human use, there are definitely right ways and wrong ways to extract the oil. And, of course, even when you’ve narrowed it down to the right ways to perform the extraction (keeping in mind the purity and potency, among other things), there are still several different “right” ways being put into practice. All of this makes it extremely difficult for consumers to know which method really is best – and where they should be spending their money.
What’s most important to remember is that, even when dealing with the exact same hemp strain, the extraction method utilized to create the oil can produce very distinct results. Even at a chemical level, you can tell which method has been used to create a specific CBD product – and that can make the difference between you getting the results you want and feeling like you’ve wasted your money.
Understanding How the CO2 Cannabis Extraction Method Works
One of the most trusted ways to extract CBD from cannabis or hemp, the CO2 extraction method is categorized into three different types: supercritical, subcritical and mid-critical. Most professional and reputable companies use the CO2 extraction method simply because it’s the safest way to create the purest product.
Far from inexpensive, the equipment needed to extract CBD with CO2 is highly technical machinery that often is separated into three distinct chambers. As expected, each chamber has its own specialized task:
- First Chamber: Pressurizes and cools the CO2 to a supercritical cold liquid state
- Second Chamber: Holds the organic plant material
- Third Chamber: That captures the final product, including the used CO2 so that it can be used again
Clean and efficient, CO2 extraction is only used by professionals, as the technical knowledge needed to operate the equipment (not to mention the expense of getting your hands on it) keeps amateurs and hobbyists away.
CO2 cannabis extraction works so well because of its ability to use pressurized carbon dioxide (that’s the CO2 part in case you missed chemistry class) to extract CBD from plants. Although other extraction methods can get the job done, CO2 works better because it becomes a solvent when frozen below -69 degrees Fahrenheit, turning it from gas form to its liquid state, and without presenting any of the risks that other solvents carry.
When using the supercritical CO2 extraction method, the liquid CO2 is pushed to the point of becoming a property that is halfway between a gas and a liquid. Known as a “supercritical” state, the CO2 now functions as both a gas and a liquid, making it ideal for chemical extraction because it doesn’t denature or damage the substance. For CBD products, which are either consumed by ingestion or absorption, making sure that the hemp oil is as safe and pure as possible, without losing any of the critical components that make it effective, is key. When done properly, CO2 extraction pulls out all of the essential trichomes and terpene oils, ensuring that the products you buy really deliver the benefits you’re looking for.
The Pros and Cons of the CO2 Extraction Method
Like anything, CO2 extraction isn’t perfect. While a popular and safe choice, there are some downsides to the process that should be considered, whether you’re a consumer or a CBD business owner. First, however, let’s focus on why CO2 really is one of the best extraction methods being used today, especially for CBD products.
Pros of CO2 Extraction
- Incredibly safe, CO2 itself is used in a variety of popular foods and beverages as an additive. Carbonated soft drinks, for example, are made possible because of CO2.
- The CO2 extraction method has also been used by many trusted food companies for years because it is so effective. In addition to creating essential oils, coffee companies use CO2 as a solvent to remove caffeine from coffee.
- The process of CO2 extraction ensures purity, which is why it’s so important for CBD products. Specifically, the cannabinoids produced by this method retain their potency without being contaminated by chlorophyll and other toxic substances. For people wanting to buy the most pure CBD products as possible, CO2 extraction is the way to go. (It’s only a few steps away from being a complete isolate, which means all other compounds are completely eliminated.)
There are, of course, a few reasons why CO2 extraction isn’t the right method for everyone. Below are a few of the cons to consider…
Cons of CO2 Extraction
- The equipment needed to perform CO2 extraction is costly, with even starter kits running close to $40,000 each. Because of the cost, CO2 extraction is impossible for many companies and individuals looking to extract their own hemp oil.
- Even if you get your hands on the equipment necessary for CO2 extraction, it takes a lot of specific knowledge to make sure it’s operated properly and safely. Even an amateur chemist shouldn’t attempt to use CO2 equipment without professional training.
- Because CO2 extraction equipment is expensive and because the knowledge needed to operate it creates a barrier to entry, CBD products created with the method tend to be more expensive than those created using a different technique. (Of course, as the saying goes, you typically get what you pay for.)
Deciding if CBD Products Created by CO2 Extraction are Right for You
Like anything you choose to consume, you have a choice in what you buy. While some consumers will decide that they’re fine using CBD products created using a different method, especially if it means they save money, a lot of people choose to exclusively use CO2 extracted CBD simply because it’s the safest most effective way to ensure they’re getting the benefits they want. At the end of the day, remember that how your CBD products are made will ultimately affect the end product, as well as your overall health.
A cannabis concentrate made through CO2 extraction, which uses CO2 as a solvent to strip the cannabis plant of cannabinoids and terpenes into a concentrate. CO2 oil can be high in THC, CBD, or another cannabinoid or specific terpene, and be of varying consistencies—the “CO2” in its name merely defines the process used to make it.
What is CO2 oil?
CO2 oil is a term used to describe any cannabis concentrate created by CO2 extraction. CO2 extraction relies on a closed-loop system and the chemical is purged from the final product.
CO2 oils can be of varying consistencies, such as shatter, crumble, honey, oil, etc. They can also be high in THC, CBD, or another cannabinoids or specific terpene.
How to use CO2 oil
CO2 oil is vaporized. It can come in vape cartridges and consumed through a vape pen, or as a concentrate, or dab, in the form of a shatter or wax. If in one of these forms, CO2 oil needs to be flash vaporized and consumed through a dab rig.
How to Extract CBD Oil from Hemp & Cannabis Using CO2 Extraction
The CBD industry has coined a reputation of the Wild West due to the lack of regulation around the labeling and manufacturing standards. Research is one of the paramount considerations one should take when looking for CBD oils.
The source of hemp is very important, but the extraction method can make or break the quality of the end product.
Fly-by-night companies cut costs by utilizing chemicals such as butane and hexane. Aside from lying to customers and destroying volatile terpenes, chemical solvent extraction may leave a toxic residue if not purged properly.
Let’s make it clear, we don’t want to ingest toxic chemicals in a product that is supposed to be healthy.
That’s why you should purchase from brands that use CO2 extraction technology. This method ensures that the end product contains more terpenes and cannabinoids because it doesn’t use additional heat or solvents.
There is a reason why CO2 extraction is becoming popular. A study by Jin et al., published in the journal Natural Product Communications, examined the effects of supercritical CO2 extraction on a type of Japanese Cypress. The researchers were able to determine the essential oil makeup of the trunks and leaves of the tree.
Let’s take a closer look at CO2 extraction and its benefits for CBD users.
What is CBD CO2 Extraction
CO2 extraction involves the use of pressurized carbon dioxide to pull as many desirable compounds from the cannabis plant as possible — including cannabinoids, terpenes, and the plant’s essential waxes. What you get is a healthy-looking, gold, and viscous extract that you can later suspend in a carrier oil or use with thinners to make it vapable.
For CO2 extraction, versatility is the name of the game. When put under a specific temperature and pressure range, it can act as a solvent, but without the dangers associated with toxic solvents like butane or hexane. In its supercritical state, CO2 yields premium-quality extracts with consistent potency levels and exceptionally high purity.
A funny thing is that CO2 extraction isn’t reserved exclusively for CBD oils. In fact, this is a standard method in the herbal and food industries. If you have decaf coffee in your kitchen, then you have a product that relies on CO2 extraction to pull caffeine from coffee beans. Also, the majority of essential oil production relies on this technology.
Forward-thinking companies realized that traditional extraction methods carried certain risks, such as flammability, solvent toxicity, and wastefulness. Before supercritical CO2 was introduced, brands had relied on solvents such as methylene chloride, trichloroethane, or ethyl acetate — all of which are far from safe.
What Does “Supercritical CO2 Extraction” Mean?
There are a few ways to make CBD oils using CO2 extraction, but supercritical CO2 extraction is widely believed to be the industry’s golden standard. This technology relies on a process known as supercritical fluid extraction. The process involves using supercritical fluids to pull one component from another. CO2 is the most commonly used ingredient in this process, although some manufacturers modify it with a co-solvent such as alcohol.
At standard pressure and temperature, CO2 acts like a gas. When it comes to supercritical CO2, it remains in the fluid state of the gas, which can only happen when the producer applies pressure and temperature that are above their critical levels.
Here’s how supercritical CO2 extraction works in a nutshell:
- The extractor uses the CO2 gas and runs it through a chamber. At this point, the temperature is kept as low as -70 degrees Fahrenheit but the pressure is being gradually increased.
- The gas turns into a fluid.
- In this state, CO2 possesses both gas and liquid properties. In other words, it fills space like a gas, while maintaining the density of a liquid.
- The supercritical CO2 passes through a chamber that is filled with the raw cannabis material.
- The fluid passes through the plant material, dissolving the trichomes’ membranes. This allows the CO2 to capture a significant amount of the active compounds.
The critical temperature of CO2 has been recorded at 89.78 degrees Fahrenheit and the pressure is 73.8 bars, which translates to 7.38 million Pascals, or 1,070 pounds per square inch. This is the data from the February 2010 edition of Chemical Engineering.
In a 2014 study published by Peach and Eastoe in the Beilstein Journal of Organic Chemistry, the authors described supercritical CO2 as “a solvent like no other.” The study focused on how supercritical CO2 could contribute to the development of green chemistry.
What is Subcritical CO2 Extraction?
While subcritical CO2 extraction isn’t as common as the supercritical one, it has its place in the CBD industry. The reason why only a few manufacturers use this variation is a smaller yield and time consumption.
Basically speaking, subcritical CO2 extraction is a similar process to supercritical, but it operates on lower temperatures and lower pressure.
Although it takes more time and is less efficient, it retains more cannabinoids, terpenes, and essential oils, reflecting the original phytochemical profile of cannabis.
Unlike subcritical CO2 extraction, the supercritical method produces a thicker oil that has a consistency similar to peanut butter. That’s because the higher temperatures and pressure can extract larger compounds, such as chlorophyll, waxes, and omega-3 and 6 fatty acids. Then, the product goes through the winterization process, which removes these substances, leaving behind the filtered CBD oil.
Subcritical CO2, on the other hand, yields extracts that look and feel like molasses.
Benefits of CO2 Extraction
The major benefit of using a CO2-extracted cannabis extract is the lack of additional solvents or too high temperatures. CO2 is considered a ‘green solvent.’ The use of carbon dioxide yields cleaner and healthier products. CO2 is a natural ingredient that appears as part of the breathing process upon exhaling.
Unlike solvents such as butane, supercritical CO2 doesn’t leave behind any toxic chemical residues. It is also recyclable, which makes it cost-effective.
The benefits of CO2 extraction include:
- It is inert, non-flammable, and non-toxic.
- CO2 has moderate critical points
- The solvation potency can be fine-tuned by adjusting the compound’s density.
- It yields large quantities of pure extracts.
- CO2 enters its supercritical state in near-ambient temperatures, so it’s a perfect solvent for extracting volatile compounds.
CO2 Extraction and CBD Entourage Effect
Aside from providing a clean product, the biggest advantage of using CO2 extraction is its ability to extract larger quantities of cannabinoids and terpenes than other methods. The cannabis plant contains over 115 identified cannabinoids on top of hundreds of terpenes and flavonoids. Even though CBD and THC share many similar benefits, an increasing number of researchers now believe that the real magic happens when you can get all the naturally occurring compounds together in one product.
Although not as abundant as CBD and THC, cannabinoids such as cannabigerol (CBG) and cannabinol (CBN) have potential health benefits as well. For instance, CBN has a link with a significant decrease in physical discomfort levels, while CBG has neuroprotective effects.
Then there are terpenes, which also modulate the effects of cannabinoids. For example, limonene can increase the absorption of cannabinoids and enhance other terpenes, while alpha-pinene could counteract short-term memory problems associated with THC. Myrcene may reduce resistance in the blood-brain barrier, resulting in a more effective passage of beneficial chemicals in the body.
The above effects are described as the entourage effect. This phenomenon refers to the synergy between all cannabinoids, terpenes, and other cannabis compounds; the synergistic effects amplify the benefits of the CBD extract while modulating potential side effects. While high-quality CBD isolate has its applications, full-spectrum products are potentially a better option if the user is looking to maximize the efficacy of their CBD oil.
CO2 Extraction Equipment: Why Are Some CBD Oils More Expensive Than Others?
We’re not going to deny that supercritical CO2 extraction is expensive, which carries over to the final price of CBD oils that are extracted with this method. Companies invest heavy financial resources in equipment and the team of qualified scientists who will operate the machines. Only then can we talk about high-quality products.
An average cost of a CO2 extraction machine is around $450,000 — and there are certainly more expensive units out there. Within this price range, you can buy a machine that will process up to 200 pounds of dried plant material each day. That’s why it’s possible to produce premium CBD extracts on a broad scale. The CO2 extraction system has the biggest workloads in the industry.
The features of CO2 extraction machines include:
- High capacity
- Full automation
- The ability to mix supercritical and subcritical extractions
- A built-in CO2 storage tank.
Of course, you can find some budget-friendly powerhouses — around $175,000 — but they will be able to process less material than those from the top shelf. Such models usually process up to 107 pounds of biomass each day, which is still enough to run massive operations.
Small-scale businesses that want to employ CO2 extraction in their production practices can purchase extractors for “as little as” $4,000, although they look like dollhouses compared to the large-scale machines.
Nevertheless, one shouldn’t expect CO2-extracted CBD oils to be “cheap,” as this is a wrong oxymoron.
A Final Word on CO2 Extraction
When buying full-spectrum CBD oil, it’s wise to invest more money in a high-quality product that will not only be potent but also pure and safe for consumption. Most reputable manufacturers use supercritical CO2 extraction to make CBD extracts. Pressurized carbon dioxide yields clean and healthy products due to the lack of toxic solvent residue.
Another major benefit of CO2 extraction is the ability of CO2 to pull as many desired compounds from the plant as possible. This makes CO2-extracted CBD oil a more ‘complete’ product,’ as it squeezes the most out of the original phytochemical content of cannabis. A growing number of researchers and experts recommend such products and believe they provide better and more consistent results than isolates.
While CO2 extraction makes CBD oils more expensive than other methods, keep in mind that the investment is on both sides. The manufacturer invests a lot of money in high-tech equipment and knowledgeable staff, so the price is actually the reflection of that investment. No company will be charitable enough to sell their products at a loss.