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CO2 Oil

As cannabis connoisseurs seek ever purer and better products, there is an increase in popularity of extraction methods enabling us to obtain different and better-quality extracts. One of these methods is the supercritical fluid extraction, which is used to produce the so-called “CO2 oil”.

Cannabis users are becoming more and more interested in terpenes. Therefore, extraction experts begin to focus on methods which take preferably higher content of terpenes into consideration. For this process of production cannabis extracts, the supercritical fluid extraction is an ideal method.


Critical limit

Supercritical fluid extraction (SFE) uses special properties of gases that are compressed over their critical limit. Carbon dioxide (CO2) is the most widely used gas, as it reaches its critical point at a temperature of 32 °C, which is low enough not to destroy or transform delicate plant terpenes and cannabinoids to different substances. Furthermore, the shape of the CO2 molecule enables it to work as a non-polar solvent, just like butane or hexane.

A supercritical liquid behaves like a liquid and gas at the same time. It permeates through solid matter like gas, while also dissolving compounds like a liquid. Liquids have almost zero surface voltage – that is why they easily penetrate the cuticle of cannabis trichomes, dissolving all oils in its path. Thanks to the fact that the supercritical fluid extraction extracts more terpenes, the extracts tend to be less sticky and more fluid than in the case of butane extraction, making them perfectly suitable for the ever more popular “vape pens”.

Aside from the benefits the supercritical fluid extractions offer when it comes to selectivity (the ability to select extracts of different composition from the same source material), CO2 is also a relatively eco-friendly and safe solvent – unlike petroleum derivates of butane and hexane or others.

CO2 olej