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]
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| Names | |||
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| 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
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| Identifiers | |||
3D model (JSmol)
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| ChEMBL | |||
| ChemSpider | |||
| ECHA InfoCard | 100.000.853 | ||
| EC Number |
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PubChem CID
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| RTECS number |
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| UNII | |||
| UN number | 1958 | ||
CompTox Dashboard (EPA)
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| 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 | |||
| Occupational safety and health (OHS/OSH): | |||
Main hazards
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Ozone depletor | ||
| GHS labelling: | |||
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| Warning | |||
| H420 | |||
| P410 P403, P502 | |||
| Flash point | nonflammable[1] | ||
| Lethal dose or concentration (LD, LC): | |||
LC50 (median concentration)
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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)
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TWA 1000 ppm (7000 mg/m3)[1] | ||
REL (Recommended)
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TWA 1000 ppm (7000 mg/m3)[1] | ||
IDLH (Immediate danger)
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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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Uses
editWhen 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
editAside from its immense environmental impacts, R114, like most chlorofluoroalkanes, forms phosgene gas when exposed to a naked flame.[5]
References
edit- ^ a b c d e f g h NIOSH Pocket Guide to Chemical Hazards. "#0201". National Institute for Occupational Safety and Health (NIOSH).
- ^ "Dichlorotetrafluoroethane". Immediately Dangerous to Life or Health Concentrations (IDLH). National Institute for Occupational Safety and Health (NIOSH).
- ^ United States Environmental Protection Agency (17 July 2015). "Ozone-Depleting Substances". Retrieved 16 May 2021.
- ^ Laube, Johannes C.; Mohd Hanif, Norfazrin; Martinerie, Patricia; Gallacher, Eileen; Fraser, Paul J.; Langenfelds, Ray; Brenninkmeijer, Carl A. M.; Schwander, Jakob; Witrant, Emmanuel; Wang, Jia-Lin; Ou-Yang, Chang-Feng; Gooch, Lauren J.; Reeves, Claire E.; Sturges, William T.; Oram, David E. (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. Bibcode:2016ACP....1615347L. doi:10.5194/acp-16-15347-2016.
- ^ "False Alarms: The Legacy of Phosgene Gas". HVAC School. 4 January 2021. Retrieved 9 May 2022.
External links
edit- Material Safety Data Sheet from Honeywell International Inc., dated 22 August 2007.
- CDC - NIOSH Pocket Guide to Chemical Hazards