Chemistry:1,2-Dichlorotetrafluoroethane

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Short description: A type of chlorofluorocarbon
1,2-Dichlorotetrafluoroethane
1,2-dichlorotetrafluoroethane.svg
1,2-dichloro-1,1,2,2-tetrafluoroethane-3D-vdW.png
Names
Preferred IUPAC name
1,2-Dichloro-1,1,2,2-tetrafluoroethane
Other names
R-114, CFC-114, halon 242, cryofluorane, Freon 114, Genetron 114, Refrigerant 114
Identifiers
3D model (JSmol)
ChEMBL
ChemSpider
EC Number
  • 200-937-7
RTECS number
  • KI1101000
UNII
UN number 1958
Properties
C2Cl2F4
Molar mass 170.92 g/mol
Appearance colorless gas[1]
Odor faint, ether-like (high concentrations)[1]
Density 1.455 g/cm3
Melting point −94 °C (−137 °F; 179 K)
Boiling point 3.5 °C (38.3 °F; 276.6 K)
0.01%[1]
Vapor pressure 1.9 atm (21°C)[1]
Hazards
Main hazards Ozone depletor
GHS pictograms GHS04: Compressed GasGHS07: Harmful
GHS Signal word Warning
H280, H420
P410+403, P502
Flash point nonflammable [1]
Lethal dose or concentration (LD, LC):
720,000 ppm (rat, 30 min)
700,000 ppm (mouse, 30 min)
750,000 ppm (rabbit, 30 min)[2]
NIOSH (US health exposure limits):
PEL (Permissible)
TWA 1000 ppm (7000 mg/m3)[1]
REL (Recommended)
TWA 1000 ppm (7000 mg/m3)[1]
IDLH (Immediate danger)
15000 ppm[1]
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
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Infobox references

1,2-Dichlorotetrafluoroethane, or R-114, also known as cryofluorane (INN), is a chlorofluorocarbon (CFC) with the molecular formula ClF2CCF2Cl. Its primary use has been as a refrigerant. It is a non-flammable gas with a sweetish, chloroform-like odor with the critical point occurring at 145.6 °C and 3.26 MPa. When pressurized or cooled, it is a colorless liquid. It is listed on the Intergovernmental Panel on Climate Change's list of ozone depleting chemicals, and is classified as a Montreal Protocol Class I, group 1 ozone depleting substance.[3]

When used as a refrigerant, R-114 is classified as a medium pressure refrigerant.

The U.S. Navy uses R-114 in its centrifugal chillers in preference to R-11 to avoid air and moisture leakage into the system. While the evaporator of an R-11 charged chiller runs at a vacuum during operation, R-114 yields approximately 0 psig operating pressure in the evaporator.

Manufactured and sold R-114 was usually mixed with the non symmetrical isomer 1,1-dichlorotetrafluoroethane (CFC-114a), as separation of the two isomers is difficult.[4]

Dangers

Mixing ratio of CFC-114 in air (black) between 1960 and 2014. Also levels of CFC-114a are in red.

Aside from its immense environmental impacts, R114, like most chlorofluoroalkanes, forms phosgene gas when exposed to a naked flame.[5]

References

  1. 1.0 1.1 1.2 1.3 1.4 1.5 1.6 1.7 NIOSH Pocket Guide to Chemical Hazards. "#0201". National Institute for Occupational Safety and Health (NIOSH). https://www.cdc.gov/niosh/npg/npgd0201.html. 
  2. "Dichlorotetrafluoroethane". Immediately Dangerous to Life and Health Concentrations (IDLH). National Institute for Occupational Safety and Health (NIOSH). https://www.cdc.gov/niosh/idlh/76142.html. 
  3. "Ozone-Depleting Substances". 17 July 2015. https://www.epa.gov/ozone-layer-protection/ozone-depleting-substances. 
  4. Laube, Johannes C.; Mohd Hanif, Norfazrin; Martinerie, Patricia; Gallacher, Eileen; Fraser, Paul J.; Langenfelds, Ray; Brenninkmeijer, Carl A. M.; Schwander, Jakob et al. (9 December 2016). "Tropospheric observations of CFC-114 and CFC-114a with a focus on long-term trends and emissions". Atmospheric Chemistry and Physics 16 (23): 15347–15358. doi:10.5194/acp-16-15347-2016. Bibcode2016ACP....1615347L. 
  5. "False Alarms: The Legacy of Phosgene Gas". 4 January 2021. https://hvacrschool.com/phosgene-gas/. 

External links