The CO2 Extraction Process: What You Need To Know

When you think of carbon dioxide, you probably define it as the gas that we, humans, exhale. Environmentalists know it as a primary greenhouse gas that is harmful to the atmosphere. But did you know that CO2 is widely used in many different industries such as food and beverage, cosmetics, and pharmaceuticals? With the aid of a supercritical CO2 extraction machine, CO2 gas is used to extract natural oils and nutrient rich substances from a naturally occurring bioproduct. 

What Is Supercritical CO2

When CO2 is heated and pressurized above 1071 psi and 31.1°C, it reaches its so-called supercritical state. In this state, elements will both have liquid and gas properties. Supercritical elements are versatile tools for processing various extracted products. 

What makes supercritical CO2 advantageous in many applications is that it has high density and low viscosity. They can easily effuse with solids and reach small spaces and pores like gas and act as a liquid solvent to dissolve materials well. On top of this, most extractions leave no residual solvents, are non-toxic, and are more economical than other supercritical gases to maintain. 

A cleverly designed and engineered supercritical CO2 extraction machine will also help you manipulate bioproduct extractions, allowing these elements to bond with other components within your recipe. 

The CO2 Extraction Process

A powerful solvent, CO2 can extract compounds from a raw material (like plant and food) without damaging the compounds’ characteristics and essence. 

More often than not, a pressure vessel manufacturer would need to fabricate the machine since gases under pressure will be part of the extraction process. 

The CO2 extraction process entails the following: 

• Feeding of CO2 into the extraction machine

• Heating and pressurization of CO2 to reach its supercritical state

• Penetration of the supercritical CO2 into the surface of a raw material

• Extraction of desired substances from the raw material

• Heating of the supercritical CO2, turning back into a gas

• Evaporation of the CO2

• Obtaining the extracted substance from the raw reservoir designed to capture material

As stated, CO2 leaves no residual solvent and is non-toxic. So, you can guarantee that the extracted substance is clean and safe. Because CO2 gas is also inert, the extract's properties won't be altered. 

Uses and Applications

Players in various industries can tap a reputable pressure vessel manufacturer to source supercritical CO2 extraction machines and use them for various applications. 

Today, CO2 extraction is commonly used to extract pure cannabidiol or CBD from the cannabis plant, essential oils for the fragrance industry and ethanol for the energy industry. The growing hemp industry uses this process to harness the true and natural potency of CBD to treat a wide array of conditions such as anxiety, depression, insomnia, Alzheimer's, Parkinson’s, and other cancer-related pains and symptoms. 

It also has pharmaceutical and cosmetic applications. CO2 extractions can be used to extract vegetable oils from raw plants and use them as essential ingredients in many medicinal and aesthetic products. 

This extraction technique is also used in beer brewing. Because of the easy manipulation of CO2, beer manufacturers can perform selective extraction of alpha and beta acids, which can then influence a beer’s flavor and aroma. A closed loop CO2 extractor is also employed to extract caffeine from coffee beans and produce the popular decaffeinated coffee. 

Besides the food and medicine industries, experts also use supercritical CO2 and the CO2 extraction process for research and academic purposes.