Supercritical Carbon Dioxide
Contents
Basics
- Carbon Dioxide held above the Critical Point
- Here (and other Supercritical Fluids ) it behaves essentially as both a Liquid and a Gas
- It can be abbreviated as sCO2
Uses
Blowing Agent
- Involves dissolving sCO2 into the material, then rapidly depressurizing it to form a foam
- Need to look into this further for more specific details
Chemical Synthesis
- Need to look into this for specifics, but essentially using CO2 as the solvent for the reaction
- Of interest to the Pharmaceutical Industry, as the Product may be "precipitated" by expanding the mixture out of a nozzle, leaving a fine dry product akin to Spray Drying
Supercritical Fluid Chromatography
- Can be used for Analytic Chemistry, or in Simulated Moving Bed Chromatography at an industrial scale
Dry Cleaning
- Unlike other solvents sCO2 has virtually no toxicity (short of it being an Asphyxiant Hazard ) so Disposal/Handling concerns are far less
Extraction
- Supercritical fluid extraction is very common in the Essential Oil Industry (for Fragrances / Food Additives ) (
And also in the Cannabis Industry for High Value High Purity Oils/Resins/Waxes) - It is effective, and also has little risk of contamination since simply depressurizing the mixture separates out the CO2 (which can then be collected and recycled)
- Main issue is initial cost of equipment
- It is also used for Decaffeination
As a Working Fluid
- It can be used as a Refrigerant or as a Working Fluid in a Rankine Cycle (Although using Hydrocarbons in the Organic Rankine Cycle may be of more interest
- It has the advantage over Butane and other similar proposed hydrocarbons in that it is not flammable
- The Allam-Fetvedt Cycle is a novel Power Generation system utilizing Oxy-Fuel Combustion in an all Supercritical Carbon Dioxide Atmosphere
Internal Links
External Links
- The Wikipedia Page on Supercritical Carbon Dioxide
- A 2012 Paper Titled "Supercritical fluid simulated moving bed chromatography for the separation of ethyl linoleate and ethyl oleate"
- A Video by the YouTube Channel "extraktLAB" Titled "How To Do Supercritical CO2 Extraction" ( ~2 Minute Watch )
- A Video by the YouTube Channel "Applied Science" Titled "A close look at supercritical carbon dioxide CO2" ( ~8 Minute Watch )
- A Video by the YouTube Channel "Applied Science" Titled "Caffeine extraction from green coffee with supercritical CO2" ( ~10 Minute Watch )
- A Video by the YouTube Channel "Applied Science" Titled "Supercritical CO2 extraction of cinnamon, coffee, and vanilla with dry ice " ( ~6 Minute Watch )
- A Video by the YouTube Channel "Applied Science" Titled "Custom supercritical CO2 chamber with easy-to-use lid clamp" ( ~7 Minute Watch )
- A Video by the YouTube Channel "Applied Science" Titled "Effect of long-term high pressure CO2 on acrylic" ( ~2 Minute Watch )
- Seems the Acrylic is not viable for long term / non-educational demo use
- A Video by the YouTube Channel "Vidya-mitra' Titled "Supercritical fluid extraction: principle and applications (FT)" (A 30 Minute Presentation by Dr. Richa Singh from the Indian Council of Agricultural Research-National Dairy Research Institute (ICAR-NDRI) )
