CO2 Extraction: A Closer Look

CO2 Extraction: A Closer Look

  • Kirsten Thornhill - 29.09.2020

CO2 extraction? What is that for? Is it necessary? Should I know more about it? 

I’m sure these are common questions ruminating in your head. So, let’s first start with what it is. CO2 extraction is a process using pressurized carbon dioxide to pull out the desired phytochemicals from a cannabis plant. In other words, this process pulls out all of the essential cannabinoids, terpenes, flavonoids, and waxes out of the plant material. This extraction process created a brown-colored oil, CO2 oil. 



What is CO2?

Back to chemistry class in high school. CO2 is considered to be a tunable solvent, making it extremely versatile. CO2, carbon dioxide, is effective in creating multiple products, by controlling pressure and temperature. 

Why CO2?

At certain pressures and temperatures, CO2 acts like a solvent. CO2 doesn’t bring forth the same dangers as other solvents. Making it a commonly used way for creating a pure and clean quality oil which involves almost no post-processing procedures. This makes CO2 stand out from the other toxic products out there. 

What is Supercritical CO2?

Another way of talking about CO2 extraction? Supercritical CO2. It’s not the only form of extraction, but when talking about the most commonly used extraction, supercritical CO2 extraction is the go-to. Carbon dioxide (CO2) is a gas at standard pressure and temperature. But, supercritical CO2 refers to it in a fluid state. This takes place above its critical pressure and temperature. 

CO2 extraction is a conventional extraction method commonly seen in the food and supplement industries. Many individuals may not realize that carbon dioxide extraction is used for caffeine removal from coffee beans, to make decaffeinated coffee. Also, CO2 extraction is often used in the production of essential oils too. 

CO2 extraction is now an important part of the cannabis industry too. 



Here’s how it works (in layman’s terms):

Gaseous CO2 to Fluid CO2

The extractor takes CO2 in its gaseous form and runs it through a chamber where it will ensure extremely low temperatures with increased levels of pressure. This causes the gas to change into a fluid form. In this fluid state, CO2 demonstrates special properties, so when reheated and repressurized, it can become supercritical. Boom, science!

Supercritical CO2 to Cannabis

The great thing about supercritical fluid is that it has properties between gases and liquids. For example, it can fill a space like a gas would, but can still maintain a liquid-like density. Cool. 

Anyways, the supercritical fluid next passes through a chamber that contains raw cannabis. The supercritical CO2 passed through the cannabis, whilst gently dissolving the trichome membranes. Thus, the CO2 fluid captures the many active compounds of cannabis. 


Subcritical CO2

Subcritical CO2 extraction requires low temperatures and low pressures. These aren’t as common as the supercritical CO2 because they take more time and produce significantly less product. Fun fact, subcritical CO2 extractions retain the terpenes, essential oils, and other sensitive chemicals within the cannabis plant.

Why Supercritical CO2?

Regardless of whether or not you completely understand the extraction process, here’s the bulk of what you need to know.

Supercritical CO2 extraction allows the “extractors” to capture and isolate the cannabinoids, leading way for more scientific research and understanding to be conducted about cannabis. 



Studies are becoming increasingly specific about what is known and what isn’t about tetrahydrocannabinol (THC) and cannabidiol (CBD). Though THC and CBD are the most common cannabinoids, there are over one hundred other cannabinoids that are unstudied, relatively. 

Food for Thought

What if…..CBD had not been researched yet? What if we were still unaware of the medical benefits of CBD? 

Just think about it, for a second. What if it wasn’t studied? Think about the 100+ other phytocannabinoids that exist in the cannabis plant. Whoa.



CO2 extraction is key in being able to unlock the understanding of the beneficial cannabis plant. Once experts and scientists begin to understand just how the cannabinoids work independently, they can begin to understand how well they work together. 

We can only begin to start to understand the beneficial effects of cannabinoids after we understand cannabinoids independently. This is why CO2 extraction is so important (+ cool). 

What are the Benefits of CO2 Extraction?

Just one of the many great benefits of CO2 extraction is that it is customizable. 

Extraction can run supercritical liquid CO2 through the marijuana plant or hemp plant, killing any microbial bacteria, mold, mildew, or mites that are possibly on the plant. Thus, CO2 extraction can help you guarantee that your concentrates are clean and healthy for consumption. 



Due to the lack of preservation and chemicals of terpene aromas, CO2 extracted oil has a much better taste, making them ideal for cannabis concentrates for users. 

Are There Other Forms of Supercritical Extraction?

Supercritical extraction isn’t necessarily a new method of extraction and separation. More so, supercritical extraction has been around for over 20 years, first making its appearance in the 1980’s. From the extraction of essential oils for women’s perfume to extracting coffee from coffee beans to create decaffeinated coffee, supercritical CO2 has been a crucial player in numerous industries, including the cannabis industry. 

The Extraction Equipment

We understand that more than likely the majority of you won’t be purchasing a CO2 extractor, but we do want to share with you the cool equipment and process.

CO2 extraction machines are capable of producing large quantities of products that can cost A TON of money. Only lab technicians should be purchasing and using these machines, of course. 

But, something cool to note, people like you and I, can still make non-toxic, high quality cannabis concentrations at home, CO2-extracted too. All it takes is some basic materials, dry ice, and natural cannabis. 

CO2 Extraction: Cannabis vs Hemp vs Marijuana Oils

With the growing popularity of cannabis, there’s also growing popular misconceptions. As a quick gloss over, we want to share some important features of the cannabis plant. 

You can think of the cannabis plant as the sky. In the sky are both hemp plants and marijuana plants (let’s call them clouds). While these two plants share many commonalities, they are also different from one another. Let’s assume the marijuana plant is a grey cloud and the hemp plant is a white cloud. 



The marijuana grey cloud has psychoactive effects, meaning you’ll feel “a high”. On the other hand, the hemp white cloud won’t get you “high”, it only has 0.3% THC or less. 

Thus, we are using products derived from the hemp plant for human and animal consumption. 

This may sound reiterated or you may be thinking “well duh”, but we just wanted to touch on the differences quickly to make sure our readers understand the differences of the cannabis plant sky. 

Think about how many people could benefit from this remarkable herb, but don’t know much about it or only know about the misconceptions. 

CO2 Extraction: Final Thoughts

The take home message for this article is that the method of CO2 extraction matters. Supercritical CO2 extraction produces cannabis concentrates that are not only more appealing, but are much safer than other CO2 extraction methods. 

The method of extraction, using supercritical CO2, produces concentrate that are clean and of higher quality, with significantly less toxicity. 



When purchasing a cannabis product, we encourage our readers to do as much research on the methods of extractions as possible. Here, at Petly CBD, we use CO2 extraction for all of our products, ensuring the safety and quality of our products is perfect every time. Knowing what you’re giving your feline or canine is so important!

When buying cannabis products for medicinal purposes, whether it be for yourself or your four-legged friend, it’s essential to ensure that you are reaping the benefits that the cannabinoid product has to offer. 

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