Companies that create botanical extracts, such as essential oils or CBD, are always seeking to improve their means of production. That means determining the best extraction method. For many companies, that decision boils down to choosing between ethanol and supercritical CO2 extraction. Understanding how ethanol extraction differs from CO2 extraction is the best way to make that choice.
Although both methods involve immersing a plant in another substance, the main difference between CO2 and ethanol extraction is the substance used. CO2 is a gas that naturally occurs in the atmosphere, but under the right conditions, it can be put into a semi-liquid state. In this state, called a “supercritical” state, it can be used as an extraction solvent. After the plant matter passes through the CO2, the plant and oil separate from each other, since the two materials have different densities.
Benefits and Drawbacks
The main drawbacks to CO2 extraction are its complexity and cost. Putting CO2 into a supercritical state requires specialized machinery and training. Along with this, the process is not nearly as efficient, requiring far more setup and more time to complete. However, there are safety benefits in that CO2 isn’t flammable like ethanol, and it’s also environmentally friendly.
Which method you use depends on your goals and capabilities. If you have the capability for the highly complex processes of CO2 extraction, this is an option.
When some people imagine trying to extract oils from a plant, they often imagine a process similar to that of squeezing wine out of grapes. However, in order to separate the oils or essence from a plant, a solvent is needed. During ethanol extraction, that solvent is ethyl alcohol.
To perform ethanol extraction, one starts by soaking the botanical in 95% food-grade ethanol. Different botanicals will require different lengths of time for the soaking process. After this wash, the plant material is filtered out, leaving a liquid wash that contains both ethanol and oil. From here, the ethanol is processed out to be reused, leaving behind a high-quality oil.
Benefits and Drawbacks
The main issue some people have with ethanol extraction is the fact that ethanol is a flammable substance. However, it’s far less flammable than other solvents used for extraction, such as propane or butane. Ethanol extraction’s main benefit is its ease of use. The solvent itself isn’t costly or difficult to come by, and it can be reused multiple times. Along with that, the machinery required for ethanol extraction is far less complex and expensive than the machinery needed for the CO2 method.