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Chemical properties[edit]


Fluorocarbons are colorless and have high density, up to over twice that of water. They are not miscible with most organic solvents (e.g., ethanol, acetone, ethyl acetate, and chloroform), but are miscible with some hydrocarbons (e.g., hexane in some cases). They have very low solubility in water, and water has a very low solubility in them (on the order of 10 ppm). They have low refractive indices.

The partial charges
in the polarized
carbon–fluorine bond




Compound Test conditions Result
Hexafluoroethane Lower flammability limit in oxygen None
Perfluoropentane Flash point in air None
Flash point in oxygen -6 °C
Flash point nitrous oxide -32 °C
Perfluoromethylcyclohexane Lower flammability limit in air None
Lower flammability limit in oxygen 8.3%
Lower flammability limit in oxygen (50 °C) 7.4%
Lower flammability limit in nitrous oxide 7.7%
Perfluoromethyldecalin Spontaneous ignition test
in oxygen at 127 bar
No ignition at 500 °C
Spontaneous ignition in adiabatic shock
wave in oxygen, 0.98 to 186 bar
No ignition
Spontaneous ignition in adiabatic shock
wave in oxygen, 0.98 to 196 bar

Fluorocarbons have been considered as fire extinguishants to replace CFCs.[9] This extinguishing effect has been attributed to their high heat capacity, which takes heat away from the fire. It has been suggested that an atmosphere containing a significant percentage of perfluorocarbons on a space station or similar would prevent fires altogether.[10] [11] When combustion does occur, toxic fumes result, including carbonyl fluoride, carbon monoxide, and hydrogen fluoride.

Gas dissolving properties[edit]


This table shows values for the mole fraction, x1, of nitrogen dissolved, calculated from the Ostwald coefficient, at 298.15 K (25 °C), 0.101325 M Pa.[13]

Liquid 104 x1
Water 0.118
Ethanol 3.57
Acetone 5.42
Tetrahydrofuran 5.21
Cyclohexane 7.73
Perfluoromethylcyclohexane 33.1
Perfluoro-1,3-dimethylcyclohexane 31.9



Fowler process[edit]

A major breakthrough that allowed the large scale manufacture of fluorocarbons was the Fowler process. In this process, cobalt trifluoride is used as the source of fluorine. Illustrative is the synthesis of perfluorohexane:

C6H14 + 28 CoF3 → C6F14 + 14 HF + 28 CoF2


2 CoF2 + F2 → 2 CoF3

Industrially, both steps are combined, for example in the manufacture of the Flutec range of fluorocarbons by F2 chemicals Ltd, using a vertical stirred bed reactor, with hydrocarbon introduced at the bottom, and fluorine introduced halfway up the reactor. The fluorocarbon vapor is recovered from the top.

Electrochemical fluorination[edit]


2 N(C6H13)3 + 90 HF → 6 C6F14 + 2 NF3 + 84 H2

The perfluorinated amine will also be produced:


Environmental and health concerns[edit]








As well as several medical uses:

Fluoroalkenes and fluoroalkynes[edit]




Environmental and health concerns[edit]

Fluoroalkenes and fluorinated alkynes are reactive and many are toxic (perfluoroisobutene being a notable example). Fluoroalkenes are not ozone depleting, as they contain no chlorine or bromine atoms. They are too reactive to be greenhouse gases. Associated with the production of polytetrafluoroethylene is the use of various fluorinated surfactants, which have attracted concern because they bioaccumulate.

Perfluoroaromatic compounds[edit]




Compound Melting point, °C Boiling point, °C
Hexafluorobenzene 5.3 80.5
Benzene 5.5 80.1
Octafluorotoluene <-70 102-103
Toluene -95 110.6
Perfluoro(ethylbenzene) - 114-115
Ethylbenzene -93.9 136.2
Octafluoronaphthalene 86-87 209[29]
Naphthalene 80.2 217.9

See also[edit]


  3. ^ Murphy WJ (March 1947). "Fluorine Nomenclature... A statement by the Editors". Ind. Eng. Chem. 39 (3): 241–242. doi:10.1021/ie50447a004. 
  10. ^ McHale ET (1974). "Life Support Without Combustion Hazards". Fire Technology. 10 (1): 15–24. doi:10.1007/bf02590509. 
  11. ^ Huggett C (1973). "Habitable Atmospheres Which Do Not Support Combustion". Combustion and Flame. 20: 140–142. doi:10.1016/s0010-2180(73)81268-4. 
  13. ^ Battino R, Rettich TR, Tominaga T (1984). "The solubility of nitrogen and air in liquids". J. Phys. Chem. Ref. Data. 13 (2): 308–19. 
  14. ^ McBee ET (March 1947). "Fluorine Chemistry". Ind. Eng. Chem. 39 (3): 236–237. doi:10.1021/ie50447a002. 
  15. ^ Siegemund G, Schwertfeger W, Feiring A, Smart B, Behr F, Vogel H, McKusick B "Fluorine Compounds, Organic" in "Ullmann's Encyclopedia of Industrial Chemistry" 2005, Wiley-VCH, Weinheim. doi:10.1002/14356007.a11_349
  18. ^ Yamanouchi K; Yokoyama K (1975). Proceedings of the Xth International Congress for Nutrition: Symposium on Perfluorochemical Artificial Blood, Kyoto: 91.  Missing or empty |title= (help)
  20. ^ Platts DG; Fraser JF (2011). Critical Care and Resuscitation. 13 (1): 44–55.  Missing or empty |title= (help)
  21. ^ Geyer RP (1975). Proc. Xth Intern. Congress for Nutr.: Symp on Perfluorochemical Artif. Blood, Kyoto: 3–19.  Missing or empty |title= (help)
  22. ^ http://www.aluminum-production.com/anode_effect.html
  26. ^ Imamura Y; Minami M; Ueki M; Satoh B; Ikeda T (2003). "Use of perfluorocarbon liquid during vitrectomy for severe proliferative diabetic retinopathy". Br J Ophthalmol. 87 (5): 563–566. doi:10.1136/bjo.87.5.563. 
  28. ^ Banks, RE (1970). Fluorocarbons and their Derivatives, Second Edition. London: MacDonald & Co. (Publishers) Ltd. pp. 203–207. ISBN 0 356 02798 8. 

External links[edit]