CBD Extraction Methods: CO2, Ethanol, and More Explained

CBD extraction might sound overly scientific but it’s really not that complex. The goal of any extraction method is to pull CBD and other beneficial compounds (cannabinoids, terpenes, flavonoids) out of the hemp plant material.

The resulting extract can then be used to make CBD oils, capsules, topicals, edibles, vapes, and more. Although most CBD companies will claim that their extraction process is the best, the truth is that each CBD extraction method has its advantages and disadvantages. 

In this article, we’ll explore the most common CBD extraction methods — CO2, ethanol, and lipid infusion — to help you understand how they work and their pros and cons.

Carbon Dioxide (CO2) Extraction

Carbon dioxide (CO2) extraction uses carbon dioxide, the same chemical that we breathe on a daily basis. It’s the most popular method for extracting CBD. CO2 extraction is not a new process; it’s been widely used to decaffeinate coffee beans, extract spices, and remove nicotine from tobacco. 

The main advantage of CO2 extraction is that it’s highly tunable, which means you can choose what to extract by changing the temperature and pressure (1). But CO2 extraction equipment is costly and requires expertise. 

There are two CO2 extraction methods: supercritical and subcritical. Both rely on the use of pressurized carbon dioxide to act as a solvent, pulling CBD and other beneficial ingredients out of hemp plant material, after which the CO2 is depressurized and returns back into its gas form.

CO2 extraction is considered a sustainable and eco-friendly option. The CO2 used during the extraction process can be recaptured each time for later use, doesn’t leave behind any harmful residue, and is completely non-toxic and renewable. 

Supercritical CO2 Extraction

Supercritical CO2 extraction uses high pressures and temperatures to make carbon dioxide behave as both a gas and liquid at the same time: what’s called a supercritical fluid. This makes it a very efficient solvent and is the most common way of doing CO2 extraction.

Subcritical CO2 Extraction 

With subcritical CBD extraction, a lower temperature and lower pressure are used for the extraction process, which means the CO2 remains in its liquid state. This makes the extraction slower and less efficient but helps retain delicate compounds that are sensitive to high temperatures, such as terpenes.

Ethanol Extraction 

Ethanol has been used for botanical extraction for thousands of years, especially for making herbal tinctures. Ethanol extraction can be done at cold or warm temperatures.

Cold Ethanol Extraction

The cold method involves soaking hemp in pre-chilled ethanol to effectively separate the plant’s cannabinoid and terpene-containing trichomes. 

Warm Ethanol Extraction

Meanwhile, the warm method is more efficient (produces higher yields) but has the downside of pulling out undesirable compounds like fats and waxes, which require additional processing to remove. That’s why cold ethanol extraction is more popular.

Following the extraction process, the ethanol is evaporated to leave behind a crude extract. 

Ethanol extraction is relatively simple, inexpensive, and suitable for both large and small-scale cannabis processors. It also does a great job of dissolving all of hemp’s compounds, including elusive flavonoids (2).

The main downside of ethanol extraction is the high boiling point. That means when ethanol is evaporated from the solution, many of the fragile terpenes are lost as well. That’s why companies that use ethanol extraction often separately add terpenes to their products.

Isopropyl Alcohol Extraction

Isopropyl alcohol (IPA) is a different type of alcohol that’s sometimes used for cannabis and CBD extraction.

This extraction method is similar to ethanol extraction and uses the same general idea: soak the hemp flowers in alcohol to extract the desirable compounds and then purge the alcohol out of the resulting extract.

Charlotte’s Web is one of the only CBD companies that continue to use this method but only for one product because it’s considered labor-intensive.

Lipid Infusion/Olive Oil Extraction

The last major CBD extraction method to mention is lipid extraction. 

Despite the name, the process is quite simple: the hemp is soaked in olive oil, coconut oil, or another type of fat, and heat/pressure is applied. That way, the oil is infused with cannabinoids, terpenes, and other compounds. 

This extraction method is the mildest and least intrusive. It does a great job of preserving all of the plant’s ingredients, especially terpenes (2). If you’re looking for products that are as close to natural as possible, lipid infusion is a good choice.

But the downside is that it’s not very efficient and works best in small batches, which is why few CBD companies use it.

Which CBD Extraction Method is Best?

There are many ways to extract CBD and other beneficial compounds out of hemp. Each has its advantages and disadvantages and there isn’t a single “best” method. 

The bottom line is that all three extraction methods we covered can be used to make effective, high-quality, full-spectrum, broad-spectrum, and isolate CBD products. 

That’s why it’s more important to choose brands that tell you which extraction process they use rather than favoring one over the other. If a brand does not disclose such information, then you would be wise to avoid its products because transparency is important for a poorly regulated industry like CBD.

Still, if you have certain preferences then a specific extraction method might be more suitable. For example, if you want a minimally processed product, lipid infusion is arguably the best choice.