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1,1-Difluoroethane

April 16, 2024

1,1-Difluoroethane, or DFE, is an organofluorine compound with the chemical formula C2H4F2. This colorless gas is used as a refrigerant, where it is often listed as R-152a (refrigerant-152a) or HFC-152a (hydrofluorocarbon-152a). It is also used as a propellant for aerosol sprays and in gas duster products. As an alternative to chlorofluorocarbons, it has an ozone depletion potential of zero, a lower global warming potential (124) and a shorter atmospheric lifetime (1.4 years).[2][3]

1,1-Difluoroethane[1]
Difluoroethane
Difluoroethane
Names
Preferred IUPAC name
1,1-Difluoroethane
Other names
  • Difluoroethane
  • Freon 152a
  • Ethylidene difluoride
  • Ethylidene fluoride
  • HFC-152a
  • R-152a
  • DFE
  • Tinned Wind
Identifiers
  • 75-37-6 Y
3D model (JSmol)
  • Interactive image
ChEMBL
  • ChEMBL325493 Y
ChemSpider
  • 6128 Y
ECHA InfoCard 100.000.788
  • 6368
RTECS number
  • KI1410000
UNII
  • 0B1U8K2ME0 Y
  • DTXSID0024050
  • InChI=1S/C2H4F2/c1-2(3)4/h2H,1H3 Y
    Key: NPNPZTNLOVBDOC-UHFFFAOYSA-N Y
  • InChI=1/C2H4F2/c1-2(3)4/h2H,1H3
    Key: NPNPZTNLOVBDOC-UHFFFAOYAM
  • FC(F)C
Properties
C2H4F2
Molar mass 66.05 g/mol
Density 900 g/L @ 25 °C
Melting point −117 °C (−179 °F; 156 K)
Boiling point −24.7 °C (−12.5 °F; 248.5 K)
Critical point (T, P) 113.45 °C
0.54% @ 0 °C
Vapor pressure
  • 536 kPa (4020 mmHg) @ 21.1 °C
  • 510 kPa (5.1 bar) @ 20 °C
Viscosity 8.87 μPa·s (0.00887 cP) @ 25 °C
Hazards
Occupational safety and health (OHS/OSH):
Main hazards
 Extremely flammable
GHS labelling:
Danger
NFPA 704 (fire diamond)
Health 1: Exposure would cause irritation but only minor residual injury. E.g. turpentineFlammability 4: Will rapidly or completely vaporize at normal atmospheric pressure and temperature, or is readily dispersed in air and will burn readily. Flash point below 23 °C (73 °F). E.g. propaneInstability 0: Normally stable, even under fire exposure conditions, and is not reactive with water. E.g. liquid nitrogenSpecial hazards (white): no code
1
4
0
Safety data sheet (SDS) SDS for 1,1-difluoroethane
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
Y verify (what is YN ?)

Production edit

1,1-Difluoroethane is a synthetic substance that is produced by the mercury-catalyzed addition of hydrogen fluoride to acetylene:[4]

HCCH + 2 HF → CH3CHF2

The intermediate in this process is vinyl fluoride (C2H3F), the monomeric precursor to polyvinyl fluoride.

Uses edit

With a relatively low global warming potential (GWP) index of 124 and favorable thermophysical properties, 1,1-difluoroethane has been proposed as an environmentally friendly alternative to R134a. Despite its flammability, R152a also presents operating pressures and volumetric cooling capacity (VCC) similar to R134a so it can be used in large chillers[5] or in more particular applications like heat pipe finned heat exchangers.[6]

Furthermore, 1,1-difluoroethane is also commonly used in gas dusters and numerous other retail aerosol products, particularly those subject to stringent volatile organic compound (VOC) requirements.

The molecular weight of difluoroethane is 66, making it a useful and convenient tool for detecting vacuum leaks in Gas chromatography–mass spectrometry (GC-MS) systems. The cheap and freely available gas has a molecular weight and fragmentation pattern (base peak 51 m/z in typical EI-MS,[7] major peak at 65 m/z) distinct from anything in air. If mass peaks corresponding to 1,1-difluoroethane are observed immediately after spraying a suspect leak point, leaks may be identified.

Safety edit

Difluoroethane is an extremely flammable gas, which decomposes rapidly on heating or burning, producing toxic and irritating fumes, including hydrogen fluoride and carbon monoxide.[8]

In a DuPont study, rats were exposed to up to 25,000 ppm (67,485 mg/m3) for six hours daily, five days a week for two years. This has become the no-observed-adverse-effect level for this substance. Prolonged exposure to 1,1-difluoroethane has been linked in humans to the development of coronary disease and angina.[9] Repeated or sufficiently high levels of exposure, particularly purposeful inhalation, can precipitate fatal cardiac arrhythmia.[10]

Abuse edit

Difluoroethane is an intoxicant with abuse potential.[10][11][12][13] It appears to act primarily through GABAA and glutamate receptors.[14][15] Fatalities linked to difluoroethane abuse include actress Skye McCole Bartusiak, singer Aaron Carter and wrestler Mike Bell.[16] Bitterants, added voluntarily to some brands to deter purposeful inhalation, are often not legally required; they do not negate or counteract difluoroethane's intoxicating effects.

Environmental abundance edit

 
Growth of HFC-152a in Earth's atmosphere since year 2000.[17]
 
HFC-152a measured by the Advanced Global Atmospheric Gases Experiment (AGAGE) in the lower atmosphere (troposphere) at stations around the world. Abundances are given as pollution free monthly mean mole fractions in parts-per-trillion.


Most production, use, and emissions of HFC-152a have occurred within Earth's more industrialized and populated northern hemisphere following the substance's introduction in the 1990s. Its concentration in the northern troposphere reached an annual average of about 10 parts per trillion by year 2011.[17] The concentration of HFC-152a in the southern troposphere is about 50% lower due to its removal rate (i.e. lifetime) of about 1.5 years being similar in magnitude to the global atmospheric mixing time of one to two years.[18]

See also edit

References edit

  1. ^ 1,1-Difluoroethane at Sigma-Aldrich
  2. ^ "Changes in Atmospheric Constituents and in Radiative Forcing" (PDF). Cambridge University Press. 2007. p. 212. Retrieved 11 May 2017. 18 February 2019
  3. ^ . U.S. Environmental Protection Agency. 2010. Archived from the original on 16 October 2010. Retrieved 20 September 2010.
  4. ^ Siegemund, Günter; Schwertfeger, Werner; Feiring, Andrew; Smart, Bruce; Behr, Fred; Vogel, Herward; McKusick, Blaine (2010). "Fluorine Compounds, Organic". In Bohnet, Matthias; Bellussi, Giuseppe; Bus, James; et al. (eds.). Ullmann's Encyclopedia of Industrial Chemistry. John Wiley & Sons. doi:10.1002/14356007.a11_349. ISBN 978-3527306732.
  5. ^ Longo, Giovanni A.; Zilio, Claudio; Righetti, Giulia (2015). "Condensation of the low GWP refrigerant HFC152a inside a Brazed Plate Heat Exchanger". Experimental Thermal and Fluid Science. 68: 509–515. doi:10.1016/j.expthermflusci.2015.06.010.
  6. ^ Righetti, Giulia; Zilio, Claudio; Mancin, Simone; Longo, Giovanni A. (2018). "Heat Pipe Finned Heat Exchanger for Heat Recovery: Experimental Results and Modeling". Heat Transfer Engineering. 39 (12): 1011–1023. Bibcode:2018HTrEn..39.1011R. doi:10.1080/01457632.2017.1358483. S2CID 126263840.
  7. ^ Ethane, 1,1-difluoro- in Linstrom, Peter J.; Mallard, William G. (eds.); NIST Chemistry WebBook, NIST Standard Reference Database Number 69, National Institute of Standards and Technology, Gaithersburg (MD) (retrieved 2023)
  8. ^ "1,1-Difluoroethane". WebWISER. U.S. National Library of Medicine. Retrieved 2 April 2022.
  9. ^ "1,1-Difluoroethane". National Library of Medicine HSDB Database. 1994. Retrieved 8 June 2010.
  10. ^ a b Avella J, Wilson JC, Lehrer M (March 2006). "Fatal cardiac arrhythmia after repeated exposure to 1,1-difluoroethane (DFE)". The American Journal of Forensic Medicine and Pathology. 27 (1): 58–60. doi:10.1097/01.paf.0000202715.71009.0e. PMID 16501351. S2CID 22312214.
  11. ^ Broussard LA, Brustowicz T, Pittman T, Atkins KD, Presley L (November 1997). "Two traffic fatalities related to the use of difluoroethane". Journal of Forensic Sciences. 42 (6): 1186–7. doi:10.1520/JFS14284J. PMID 9397568.
  12. ^ Hahn, T; Avella, J; Lehrer, M (2006). "A motor vehicle accident fatality involving the inhalation of 1,1-difluoroethane". Journal of Analytical Toxicology. 30 (8): 638–42. doi:10.1093/jat/30.8.638. PMID 17132266.
  13. ^ . The Times News. 10 March 2012. Archived from the original on 12 March 2012.
  14. ^ Novotny, Clara B; Irvin, Sarah; Espiridion, Eduardo D (2019). "Acute Psychosis Following 1,1-Difluoroethane Inhalation". Cureus. 11 (9): e5565. doi:10.7759/cureus.5565. ISSN 2168-8184. PMC 6820689. PMID 31695984.
  15. ^ Custer, Adam; Corse, Andrew; Vazirani, Sondra (June 2020). "Difluoroethane Inhalant Abuse, Skeletal Fluorosis, and Withdrawal". Federal Practitioner. 37 (6): 288–289. ISSN 1078-4497. PMC 7357883. PMID 32669782.
  16. ^ Duke, Alan (22 July 2014). "'Patriot' actress Skye McCole Bartusiak dead at 21". CNN. Retrieved 24 February 2019.
  17. ^ a b "HFC-152a". NOAA Earth System Research Laboratories/Global Monitoring Division. Retrieved 12 February 2021.
  18. ^ Greally, B.R.; et al. (2007). "Observations of 1,1-difluoroethane (HFC-152a) at AGAGE and SOGE monitoring stations in 1994–2004 and derived global and regional emission estimates". Journal of Geophysical Research. 112 (D06308). Bibcode:2007JGRD..112.6308G. doi:10.1029/2006JD007527.

April 16, 2024
difluoroethane, organofluorine, compound, with, chemical, formula, c2h4f2, this, colorless, used, refrigerant, where, often, listed, 152a, refrigerant, 152a, 152a, hydrofluorocarbon, 152a, also, used, propellant, aerosol, sprays, duster, products, alternative,. 1 1 Difluoroethane or DFE is an organofluorine compound with the chemical formula C2H4F2 This colorless gas is used as a refrigerant where it is often listed as R 152a refrigerant 152a or HFC 152a hydrofluorocarbon 152a It is also used as a propellant for aerosol sprays and in gas duster products As an alternative to chlorofluorocarbons it has an ozone depletion potential of zero a lower global warming potential 124 and a shorter atmospheric lifetime 1 4 years 2 3 1 1 Difluoroethane 1 Difluoroethane DifluoroethaneNamesPreferred IUPAC name 1 1 DifluoroethaneOther names DifluoroethaneFreon 152aEthylidene difluorideEthylidene fluorideHFC 152aR 152aDFETinned WindIdentifiersCAS Number 75 37 6 Y3D model JSmol Interactive imageChEMBL ChEMBL325493 YChemSpider 6128 YECHA InfoCard 100 000 788PubChem CID 6368RTECS number KI1410000UNII 0B1U8K2ME0 YCompTox Dashboard EPA DTXSID0024050InChI InChI 1S C2H4F2 c1 2 3 4 h2H 1H3 YKey NPNPZTNLOVBDOC UHFFFAOYSA N YInChI 1 C2H4F2 c1 2 3 4 h2H 1H3Key NPNPZTNLOVBDOC UHFFFAOYAMSMILES FC F CPropertiesChemical formula C2H4F2Molar mass 66 05 g molDensity 900 g L 25 CMelting point 117 C 179 F 156 K Boiling point 24 7 C 12 5 F 248 5 K Critical point T P 113 45 CSolubility in water 0 54 0 CVapor pressure 536 kPa 4020 mmHg 21 1 C510 kPa 5 1 bar 20 CViscosity 8 87 mPa s 0 00887 cP 25 CHazardsOccupational safety and health OHS OSH Main hazards Extremely flammableGHS labelling PictogramsSignal word DangerNFPA 704 fire diamond 140Safety data sheet SDS SDS for 1 1 difluoroethaneExcept where otherwise noted data are given for materials in their standard state at 25 C 77 F 100 kPa Y verify what is Y N Infobox references Contents 1 Production 2 Uses 3 Safety 3 1 Abuse 4 Environmental abundance 5 See also 6 ReferencesProduction edit1 1 Difluoroethane is a synthetic substance that is produced by the mercury catalyzed addition of hydrogen fluoride to acetylene 4 HCCH 2 HF CH3CHF2The intermediate in this process is vinyl fluoride C2H3F the monomeric precursor to polyvinyl fluoride Uses editWith a relatively low global warming potential GWP index of 124 and favorable thermophysical properties 1 1 difluoroethane has been proposed as an environmentally friendly alternative to R134a Despite its flammability R152a also presents operating pressures and volumetric cooling capacity VCC similar to R134a so it can be used in large chillers 5 or in more particular applications like heat pipe finned heat exchangers 6 Furthermore 1 1 difluoroethane is also commonly used in gas dusters and numerous other retail aerosol products particularly those subject to stringent volatile organic compound VOC requirements The molecular weight of difluoroethane is 66 making it a useful and convenient tool for detecting vacuum leaks in Gas chromatography mass spectrometry GC MS systems The cheap and freely available gas has a molecular weight and fragmentation pattern base peak 51 m z in typical EI MS 7 major peak at 65 m z distinct from anything in air If mass peaks corresponding to 1 1 difluoroethane are observed immediately after spraying a suspect leak point leaks may be identified Safety editDifluoroethane is an extremely flammable gas which decomposes rapidly on heating or burning producing toxic and irritating fumes including hydrogen fluoride and carbon monoxide 8 In a DuPont study rats were exposed to up to 25 000 ppm 67 485 mg m3 for six hours daily five days a week for two years This has become the no observed adverse effect level for this substance Prolonged exposure to 1 1 difluoroethane has been linked in humans to the development of coronary disease and angina 9 Repeated or sufficiently high levels of exposure particularly purposeful inhalation can precipitate fatal cardiac arrhythmia 10 Abuse edit Difluoroethane is an intoxicant with abuse potential 10 11 12 13 It appears to act primarily through GABAA and glutamate receptors 14 15 Fatalities linked to difluoroethane abuse include actress Skye McCole Bartusiak singer Aaron Carter and wrestler Mike Bell 16 Bitterants added voluntarily to some brands to deter purposeful inhalation are often not legally required they do not negate or counteract difluoroethane s intoxicating effects Environmental abundance edit nbsp Growth of HFC 152a in Earth s atmosphere since year 2000 17 nbsp HFC 152a measured by the Advanced Global Atmospheric Gases Experiment AGAGE in the lower atmosphere troposphere at stations around the world Abundances are given as pollution free monthly mean mole fractions in parts per trillion Most production use and emissions of HFC 152a have occurred within Earth s more industrialized and populated northern hemisphere following the substance s introduction in the 1990s Its concentration in the northern troposphere reached an annual average of about 10 parts per trillion by year 2011 17 The concentration of HFC 152a in the southern troposphere is about 50 lower due to its removal rate i e lifetime of about 1 5 years being similar in magnitude to the global atmospheric mixing time of one to two years 18 See also editList of refrigerants IPCC list of greenhouse gases Canned airReferences edit 1 1 Difluoroethane at Sigma Aldrich Changes in Atmospheric Constituents and in Radiative Forcing PDF Cambridge University Press 2007 p 212 Retrieved 11 May 2017 18 February 2019 Global Warming Potentials of ODS Substitutes U S Environmental Protection Agency 2010 Archived from the original on 16 October 2010 Retrieved 20 September 2010 Siegemund Gunter Schwertfeger Werner Feiring Andrew Smart Bruce Behr Fred Vogel Herward McKusick Blaine 2010 Fluorine Compounds Organic In Bohnet Matthias Bellussi Giuseppe Bus James et al eds Ullmann s Encyclopedia of Industrial Chemistry John Wiley amp Sons doi 10 1002 14356007 a11 349 ISBN 978 3527306732 Longo Giovanni A Zilio Claudio Righetti Giulia 2015 Condensation of the low GWP refrigerant HFC152a inside a Brazed Plate Heat Exchanger Experimental Thermal and Fluid Science 68 509 515 doi 10 1016 j expthermflusci 2015 06 010 Righetti Giulia Zilio Claudio Mancin Simone Longo Giovanni A 2018 Heat Pipe Finned Heat Exchanger for Heat Recovery Experimental Results and Modeling Heat Transfer Engineering 39 12 1011 1023 Bibcode 2018HTrEn 39 1011R doi 10 1080 01457632 2017 1358483 S2CID 126263840 Ethane 1 1 difluoro in Linstrom Peter J Mallard William G eds NIST Chemistry WebBook NIST Standard Reference Database Number 69 National Institute of Standards and Technology Gaithersburg MD retrieved 2023 1 1 Difluoroethane WebWISER U S National Library of Medicine Retrieved 2 April 2022 1 1 Difluoroethane National Library of Medicine HSDB Database 1994 Retrieved 8 June 2010 a b Avella J Wilson JC Lehrer M March 2006 Fatal cardiac arrhythmia after repeated exposure to 1 1 difluoroethane DFE The American Journal of Forensic Medicine and Pathology 27 1 58 60 doi 10 1097 01 paf 0000202715 71009 0e PMID 16501351 S2CID 22312214 Broussard LA Brustowicz T Pittman T Atkins KD Presley L November 1997 Two traffic fatalities related to the use of difluoroethane Journal of Forensic Sciences 42 6 1186 7 doi 10 1520 JFS14284J PMID 9397568 Hahn T Avella J Lehrer M 2006 A motor vehicle accident fatality involving the inhalation of 1 1 difluoroethane Journal of Analytical Toxicology 30 8 638 42 doi 10 1093 jat 30 8 638 PMID 17132266 Autopsy man in crash died from inhaling computer cleaner The Times News 10 March 2012 Archived from the original on 12 March 2012 Novotny Clara B Irvin Sarah Espiridion Eduardo D 2019 Acute Psychosis Following 1 1 Difluoroethane Inhalation Cureus 11 9 e5565 doi 10 7759 cureus 5565 ISSN 2168 8184 PMC 6820689 PMID 31695984 Custer Adam Corse Andrew Vazirani Sondra June 2020 Difluoroethane Inhalant Abuse Skeletal Fluorosis and Withdrawal Federal Practitioner 37 6 288 289 ISSN 1078 4497 PMC 7357883 PMID 32669782 Duke Alan 22 July 2014 Patriot actress Skye McCole Bartusiak dead at 21 CNN Retrieved 24 February 2019 a b HFC 152a NOAA Earth System Research Laboratories Global Monitoring Division Retrieved 12 February 2021 Greally B R et al 2007 Observations of 1 1 difluoroethane HFC 152a at AGAGE and SOGE monitoring stations in 1994 2004 and derived global and regional emission estimates Journal of Geophysical Research 112 D06308 Bibcode 2007JGRD 112 6308G doi 10 1029 2006JD007527 Retrieved from https en wikipedia org w index php title 1 1 Difluoroethane amp oldid 1215519104, wikipedia, wiki, book, books, library,

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