What is a Supercritical Fluid?

A supercritical fluid (SCF) is any substance above its critical temperature and pressure; the fluid has the properties of both gas and liquid while not exhibiting a distinct liquid or gaseous phase. Thus, an SCF is,

• Dense like a liquid to dissolve materials

• Has low viscosity, high diffusivity, no surface tension like a gas

Carbon dioxide is the most commonly used supercritical fluid and becomes supercritical at 31^oC and 74 BAR. There are many applications for scCO₂, including decaffeination of coffee, extraction of natural products, and waterless textile dyeing.

Carbon dioxide is environmentally friendly, non-toxic and in our case most of the CO₂ is internally recycled with very little vented to the atmosphere. scCO₂ based operations represent a very “green” technology.

Visit our site for more information.

Natural Products Extracts Without Hexane

Hexane is a commonly used solvent in natural products and essential oil extractions, but hexane has been categorized as a hazardous air pollutant by the US EPA, and is included on their list of toxic chemicals.

Despite best efforts, facilities using hexane may leak up to 6,000 pounds of hexane a day into the atmosphere. In addition, extracts will contain undesirable hexane residue. The solution: Supercritical Fluid extractions.

• No hazardous waste
• No chemical residue
• No health hazard
• Environmentally friendly

View the Applied Separations website for information about natural products extractions and supercritical fluids.

Environmentally Friendly Essential Oil Extractions

The use of essential oils has become "essential" for modern living. Essential oils can be primary ingredients in perfumes for cosmetics or soaps and detergents. They form the basis of the spices in our foods. Essential oils are the base for aromatherapy.

What if there was a way to extract essential oils quickly and efficiently, without compromising the quality of the extract? There is. Supercritical carbon dioxide.

With supercritical fluids:

• No Solvent residue. No health hazard. Maintains a "natural" state. 
• Mild Extraction Conditions – 31°C temperature 
• Fractionation - easy using only CO₂ - CO₂ is a "tunable solvent" – easily change your temperature/pressure to suit your material 

Supercritical CO₂ can also be used in conjunction with more traditional methods such as soaking perfume feedstocks in an organic solvent for a period of time. The organic solvents containing the extracted the perfumes (essential oils) and accompanying waxes is then decanted and evaporated, leaving a concrete. The essential oils can easily be separated from the wax with supercritical CO₂. Because of the low temperature, the process gives high recoveries.

Click here to see an example of a supercritical system for the extraction of essential oils.

Visit Applied Separations for more information.

Replace Hexane in Your Essential Oil Extractions

Hexane is a commonly used solvent in natural products and essential oil extractions. But Hexane has been categorized as a hazardous air pollutant by the US EPA, and is included on their list of toxic chemicals. Despite best efforts, facilities using hexane may leak up to 6,000 pounds of hexane a day into the atmosphere. In addition, extracts will contain undesirable hexane residue.

The solution: Supercritical Fluid extractions.

• No hazardous waste
• No chemical residue
• No health hazard
• Environmentally friendly

Click here for information about supercritical fluids.

Click here for information about extracting essential oils with supercritical fluids.

What is a Supercritical Fluid, Anyway?

We learned in elementary school about water, gas, liquid, and plasma states, but there is another – Supercritical!

Carbon dioxide is in its supercritical fluid state when both the temperature and pressure equal or exceed the critical point of 31°C and 73 atm (see diagram). In its supercritical state, CO₂ has both gas-like and liquid-like qualities, and it is this dual characteristic of supercritical fluids that provides the ideal conditions for extracting compounds with a high degree of recovery in a short period of time.

By controlling or regulating pressure and temperature, the density, or solvent strength, of supercritical fluids can be altered to simulate organic solvents ranging from chloroform to methylene chloride to hexane. This dissolving power can be applied to purify, extract, fractionate, infuse, and recrystallize a wide array of materials.

Because CO₂ is non-polar, a polar organic co-solvent (or modifier) can be added to the supercritical fluid for processing polar compounds. By controlling the level of pressure/temperature/modifier, supercritical CO₂ can dissolve a broad range of compounds, both polar and non-polar.

To see some of the uses for supercritical fluids, visit the Applied Separations website, and view the presentation on our YouTube channel.

https://www.youtube.com/watch?v=5G4zZ3hNr2U

Create Non-Toxic, Therapeutic / Food Grade Essential Oils Easily and Cost Effectively

The use of essential oils has become "essential" for modern living. Essential oils can be primary ingredients in perfumes for cosmetics or soaps and detergents. They form the basis of the spices in our foods. Essential oils are the base for aromatherapy.

What if there was a way to extract essential oils quickly and efficiently, without compromising the quality of the extract? There is. Supercritical carbon dioxide.

With supercritical fluids:

• No Solvent residue. No health hazard. Maintains a "natural" state. 
• Mild Extraction Conditions – 31°C temperature 
• Fractionation - easy using only CO₂ - CO₂ is a "tunable solvent" – easily change your temperature/pressure to suit your material 

Concrete/Oleoresin created with
Supercritical Fluid Extraction

Supercritical CO₂ can also be used in conjunction with more traditional methods such as soaking perfume feedstocks in an organic solvent for a period of time. The organic solvents containing the extracted the perfumes (essential oils) and accompanying waxes is then decanted and evaporated, leaving a concrete. The essential oils can easily be separated from the wax with supercritical CO₂. Because of the low temperature, the process gives high recoveries.

Click here to see an example of a supercritical system for the extraction of essential oils.

Visit Applied Separations for more information.

"Green" Process for the Extraction of Natural Products

The term natural products has become the "catch-all" for any compound that has been produced by a living being, e.g. plant, animal, algae. The extracted compounds are used in, or are themselves, foods, medicinals, pigments, fragrances. The process for many years was to extract from the matrix material by solvents: aqueous and petroleum based. The first large scale use of supercritical fluids in extracting natural products was the decaffeination of coffee in 1979 and since then thousands of compounds have been extracted commercially.

Growing environmental concerns have renewed interest supercritical fluids as the “green” alternative for natural products extractions. Find out how “green” your process.

http://appliedseparations.com/Supercritical/SCF_Uses/SCF_for_Natural_Products.asp