Gases for Life
USING GASES
Supercritical for super oil
By Editorial Team
Photo: Cibdol AG
Cannabidiol is a legal and drug-free hemp product with interesting properties. The best way to obtain this fine oil is through supercritical extraction with carbon dioxide.
Gases for Life
USING GASES
Supercritical for super oil
By Editorial Team
Photo: Cibdol AG
Cannabidiol is a legal and drug-free hemp product with interesting properties. The best way to obtain this fine oil is through supercritical extraction with carbon dioxide.
Cannabidiol (CBD), one of the cannabinoids, is an active substance that is obtained as CBD oil from the leaves and flowers of the hemp plant. Unlike other products derived from this raw material, it is not psychoactive. But people do attribute some very positive properties to it, claiming that it has a “relaxing, anti-inflammatory, anxiety-reducing and nausea-inhibiting” effect. As a potential natural remedy and food supplement, it is subject to approval restrictions that are not applied uniformly within Europe.
Positive experience with CBD
However, there are no restrictions on its use for cosmetic purposes. Swiss company Cibdol mixes it into skin creams, which it promotes as having particularly nourishing and protective properties. “There has been a veritable CBD craze for about five years, evidently because more and more people are very satisfied with the oil,” operations manager Liebe Griebenauw explains. “Last year saw an increase in demand for synthetic CBD, particularly in cosmetcis.”
Cibdol extracts it from the hemp plant, with the dried leaves and flowers of authorised industrial hemp varieties of the species Cannabis sativa serving as the raw material. These plants are grown in Swiss fields. In contrast to the marijuana species Cannabis indica, these hemp varieties contain only minimal traces of the psychoactive substance THC, which acts as a drug.
Gentle separation
The resin of the legal hemp plant only contains relatively small amounts of CBD, which is extracted with the hemp oil. A common extraction method involves the use of special solvents. However, an even more effective way of extracting it is to use supercritical carbon dioxide. Messer supplies the gas for this process to Arbolea, a company for research and development in the fields of natural sciences, engineering sciences, agricultural sciences and medicine. In its supercritical state, CO₂ is highly compressed and possesses enormous dissolving capacity for organic substances.
Supercritical fluids have the density of a liquid and the flow properties of a gas. Their dissolving capacity increases rapidly in the transition to this state. The gas reaches its critical point at just 31 degrees Celsius and a pressure of 74 bar. The ground hemp flowers therefore have to be heated to just above room temperature in a pressure vessel in order to extract the flower oil. Supercritical fluid extraction (SFE) facilitates precise and gentle separation of substances.
Finest quality
This ensures that the quality of the fine oil remains unimpaired. Moreover, carbon dioxide is inert and completely non-toxic. It simply vaporises after the extraction process and can then be reused as a solvent in a closed circuit.
A small proportion of THC in the unprocessed oil cannot be avoided even when using industrial hemp. However, Arbolea and Cibdol claim to remove it so thoroughly themselves that it can no longer be detected afterwards. This is done using a chromatographic method which the Swiss companies keep a closely guarded secret. “The end product is a golden oil with a CBD content of around 70 per cent,” Sean Wassermann, who is in charge of extraction and refining at the Swiss company Arbolea, explains. “The rest consists of desired substances such as fatty acids, carotenoids and terpenes. Supercritical extraction is a key factor in ensuring high product quality.”