Process Highlight: Supercritical Fluid extraction by Carbon Dioxide (CO₂)

How we extract our oils in a clean and environmentally friendly way

At Nala, we’re not just concerned about delivering a high quality, chemical-free final product, but we want to make sure the whole process from start to finish follows those values as well. 

So how exactly do we create a deodorant without chemicals? In order to keep the entire creation process one that is clean and environmentally friendly, we use ingredients derived by green technologies, such as Supercritical Fluid extraction by carbon dioxide (CO₂).


What is Supercritical Fluid Extraction?

Supercritical fluid extraction is the process of separating one component from another using supercritical fluids as the extracting solvent (3). 

A supercritical fluid is any substance with a temperature and pressure above its critical point, a thermodynamics term referring to the point where boundaries blur between states, such as that between liquids and gases. 

What does CO₂ extraction mean?

Carbon dioxide reaches a supercritical state at 1071 psi and 31.1°C. When a molecule is in a supercritical state, it has properties of both liquid and gas (1). CO₂ can reach into small spaces like gas but can also dissolve and act as a liquid solvent. The physical properties of supercritical CO₂ are also easily manipulated, which allows it to bond to any molecule (2). The gas is used to separate substances such as antioxidants, essential oils and special oils from plant material, rather than through the use of solvents. 

Processes that use toxic solvents can require hours of purging to remove the solvents that are trapped within the oil (1). CO₂ extraction, however, is a safe, clean, and highly-versatile way of extracting plant botanicals. It extracts the most potent part of a plant, creating a quality oil without having to use any toxic solvents in the process. 

Did you know decaf coffee is derived from CO₂ extraction? Brew yourself a cup while you read the rest of this article. 


What are the benefits of this process?

CO₂ extraction results in plant extracts that are clean from any organic solvents and chemicals and highly concentrated and efficacious in small concentrations. Some plant CO₂ extracts, such as Sage and Rosemary Antioxidants, are used in our deodorant as multifunction ingredients that not only enhance our product with its antiaging, regenerating, photo-protective and other properties; but also preserve it with its anti-oxidative and antimicrobial activity in cosmetics formulations.

The benefits just continue: 

  • CO₂ can be recycled, making it environmentally friendly
  • It acts as a cleaning agent, so any molds or mildews are killed during the process 
  • There is no residual solvent on the product, making the extract much purer and more concentrated 
  • The plant isn’t exposed to extreme temperatures, so it’s not degraded as it is during other extraction methods (2)
  • The extract is more stable since and has a longer shelf life

The takeaway? CO₂ extracted actives and botanicals have proven to be the cleanest, most effective way to preserve deodorants naturally. 


REFERENCES:
    1. Mark G. | Lead Toll Processor. “CO2 Extraction Process - CO2 for Botanical Extraction.” Eden Labs, www.edenlabs.com/co2-extraction/co2-extraction-process/.
    2. Steinert, Michael. “Understanding Supercritical Carbon Dioxide (CO2) Extraction.” Cole, Cole-Parmer, 1 Nov. 2019, www.coleparmer.ca/tech-article/supercritical-co2-extraction-method.
    3. Padrela, L.; Rodrigues, M.A.; Velaga, S.P.; Matos, H.A.; Azevedo, E.G. (2009). "Formation of indomethacin–saccharin cocrystals using supercritical fluid technology". European Journal of Pharmaceutical Sciences. 38 (1): 9–17. doi:10.1016/j.ejps.2009.05.010. PMID 19477273.
Photo by Kelly Sikkema