Octafluoropropane (C
3F
8) is the
perfluorocarbon
Fluorocarbons are chemical compounds with carbon-fluorine bonds. Compounds that contain many C-F bonds often has distinctive properties, e.g., enhanced stability, volatility, and hydrophobicity. Fluorocarbons and their derivatives are commerci ...
counterpart to the hydrocarbon propane. This non-flammable synthetic material has applications in semiconductor production and medicine. It is also an extremely potent
greenhouse gas.
Manufacture
Octafluoropropane can be produced either by
electrochemical fluorination Electrochemical fluorination (ECF), or electrofluorination, is a foundational organofluorine chemistry method for the preparation of fluorocarbon-based organofluorine compounds.G. Siegemund, W. Schwertfeger, A. Feiring, B. Smart, F. Behr, H. Voge ...
or by the
Fowler process using
cobalt fluoride.
Applications
In the electronics industry, octafluoropropane is mixed with oxygen and used as a
plasma etching
Plasma etching is a form of plasma processing used to fabricate integrated circuits. It involves a high-speed stream of glow discharge ( plasma) of an appropriate gas mixture being shot (in pulses) at a sample. The plasma source, known as etch spe ...
material for
SiO2 layers in semiconductor applications, as oxides are selectively etched versus their metal substrates.
In medicine, octafluoropropane may compose the gas cores of microbubble contrast agents used in
contrast-enhanced ultrasound
Contrast-enhanced ultrasound (CEUS) is the application of ultrasound contrast medium to traditional medical sonography. Ultrasound contrast agents rely on the different ways in which sound waves are reflected from interfaces between substances. ...
. Octafluoropropane microbubbles reflect sound waves well and are used to improve the ultrasound signal backscatter.
It is used in eye surgery, such as pars plana
vitrectomy
Vitrectomy is a surgery to remove some or all of the vitreous humor from the eye.
Anterior vitrectomy entails removing small portions of the vitreous humor from the front structures of the eye—often because these are tangled in an intraocular ...
procedures where a retina hole or tear is repaired. The gas provides a long-term tamponade, or plug, of a retinal hole or tear and allows re-attachment of the retina to occur over the several days following the procedure.
Under the name R-218, octafluoropropane is used in other industries as a component of refrigeration mixtures.
It has been featured in some plans for
terraforming
Mars
Mars is the fourth planet from the Sun and the second-smallest planet in the Solar System, only being larger than Mercury. In the English language, Mars is named for the Roman god of war. Mars is a terrestrial planet with a thin at ...
. With a greenhouse gas effect 24,000 times greater than
carbon dioxide
Carbon dioxide ( chemical formula ) is a chemical compound made up of molecules that each have one carbon atom covalently double bonded to two oxygen atoms. It is found in the gas state at room temperature. In the air, carbon dioxide is trans ...
(CO
2), octafluoropropane could dramatically reduce the time and resources it takes to terraform Mars.
It is the active liquid in PICO-2L dark matter bubble detector (joined
PICASSO and
COUPP
Pico may refer to:
Places The Moon
* Mons Pico, a lunar mountain in the northern part of the Mare Imbrium basin
Portugal
* Pico, a civil parish in the municipality of Vila Verde
* Pico da Pedra, a civil parish in the municipality of Ribeir ...
collaborations).
Liquid phase
* Liquid density (1.013 bar at boiling point) : 1601 kg/m
3
* Liquid/gas equivalent (1.013 bar and 15 °C (59 °F)) : 196 vol/vol
* Latent heat of vaporization (1.013 bar at boiling point) : 104.25 kJ/kg
Gaseous phase
* Gas density (1.013 bar at boiling point) : 10.3 kg/m
3
* Gas density (1.013 bar and 15 °C (59 °F)) : 8.17 kg/m
3
* Compressibility Factor (Z) (1.013 bar and 15 °C (59 °F)) : 0.975
* Specific gravity (air = 1) (1.013 bar and 21 °C (70 °F)) : 6.683
* Specific volume (1.013 bar and 21 °C (70 °F)) : 0.125 m
3/kg
* Viscosity (1.013 bar and 0 °C (32 °F)) : 0.000125 Poise
* Thermal conductivity (1.013 bar and 0 °C (32 °F)) : 12.728 mW/(m·K)
* Thermal Conductivity, Gas @ 101.325 kPa and 25 °C: 13.8 mW/(m·K)
* Vapour Pressure @ 21.1 °C: 792 kPa
Major hazards
*
Greenhouse gas
*
Inert gas asphyxiation
Inert gas asphyxiation is a form of asphyxiation which results from breathing a physiologically inert gas in the absence of oxygen, or a low amount of oxygen, rather than atmospheric air (which is composed largely of nitrogen and oxygen). Examples ...
References
{{reflist
External links
Red Planet Turning Green?
Perfluoroalkanes
Refrigerants