利用者:Invisible invincible/sandbox2

Invisible invincible/sandbox2
	IUPAC名 1,1,1,2,2-Pentafluoroethane
	別称 Pentafluoroethane, Genetron HFC 125, Khladon 125, Suva 125, Freon 125, Fc-125, R-125
識別情報
CAS登録番号	354-33-6
PubChem	9633
ChemSpider	9256
UNII	6TQ8593LRQ
EC番号	206-557-8
	SMILES FC(F)C(F)(F)F;
	InChI InChI=1S/C2HF5/c3-1(4)2(5,6)7/h1H Key: GTLACDSXYULKMZ-UHFFFAOYSA-N ; InChI=1/C2HF5/c3-1(4)2(5,6)7/h1H Key: GTLACDSXYULKMZ-UHFFFAOYAX;
特性
化学式	C2HF5
モル質量	120.02 g/mol
外観	無色の気体
密度	1.53 g/cm3 (液体, −48.5 °C)
融点	−103.0 °C, 170 K, -153 °F
沸点	−48.5 °C, 225 K, -55 °F
蒸気圧	1414.05 kPa (25 °C)
	特記なき場合、データは常温 (25 °C)・常圧 (100 kPa) におけるものである。

ペンタフルオロエタン（英: Pentafluoroethane）とは、分子式が CF₃CHF₂ であるフルオロカーボンの一種である。ペンタフルオロエタンは現在、冷媒（R-125）として使用されているほか、消火剤にも利用されている。

Pentafluoroethane does not deplete ozone so it has replaced earlier fluorinated chemicals that did.ペンタフルオロエタンはオゾンを破壊しないため、以前使用されていたオゾンを破壊するフッ化物に取って代わって使用されるようになった。 However while it has zero ozone depletion potential, it has high global warming potential, reported by the United States Environmental Protection Agency (EPA) as 3450 times that of carbon dioxide.しかしながら、ペンタフルオロエタンはオゾン破壊係数が0である一方で、高い地球温暖化係数を持っており、^[2]

冷媒としての利用[編集]

Pentafluoroethane in a near zeotropic mixture with difluoromethane is known as R-410A, a common replacement for various chlorofluorocarbons (commonly known as Freon) in new refrigerant systems.

消火剤としての利用[編集]

HFC-125 (ECARO-25 / FE-25 / NAF S 125) is a gaseous fire suppression agent which can be used in clean agent fire suppression systems. In addition, HFC-125 leaves no residue on valuable equipment and material after discharge.^[3] It is generally used in situations where water from a fire sprinkler would damage expensive equipment, or where water-based fire protection is impractical, such as museums, banks, clean rooms and hospitals. The HFC-125 clean agent is stored in a pressurized container and introduced into the hazard as a gas. The agent is odorless, colorless, electrically non-conductive, non-corrosive, and leaves no residue. It is used in occupied enclosed areas that contain high-value assets.

HFC-125 suppresses fire by absorbing heat energy at its molecular level faster than the heat can be generated, so the fire cannot sustain itself. It also forms free radicals to chemically interfere with the chain reaction of the combustion process. This makes it a highly effective fire fighting agent that is safe for people and causes no damage to equipment.

HFC-125 is considered a Clean Agent and is therefore included in the National Fire Protection Association's 2001 - Standard for Clean Agent Fire Extinguishing Systems.

環境への影響[編集]

HFC-125 is a non-ozone depleting replacement for chlorine- or bromine-containing chemicals such as Halon 1301. Due to its global warming potential (GWP) of 3500 times that of CO₂ and atmospheric lifetime of 29 years, it is included in the list of controlled substances of the Montreal Protocol.^[4]^[5]

When introduced to the market HFC-125 was not considered safe for use in occupied spaces. The US EPA Significant New Alternative Policy (SNAP) listing reflected this. Following the introduction and acceptance of the PBPK model in the NFPA standard 2001 on Clean Agent Fire Extinguishing Systems 2004 Edition, the restriction was relaxed and now HFC-125 can be used in occupied hazards. Generally, class B (flammable liquid) hazards require concentrations that exceed the agent's no-observed-adverse-effect level (NOAEL) so extra precautions must be taken to avoid prolonged exposure to the agent.

At high temperatures, pentafluoroethane will decompose and produce hydrogen fluoride. This is observable as presence of sharp, pungent odour, which can be perceived in concentrations far below a dangerous level. Other decomposition products include carbonyl fluoride, carbon monoxide and carbon dioxide. Prior to re-entry of a room where HFC-125 system has been activated to suppress a fire, the atmosphere should be tested. An Acid Scavenging Additive added to pentafluoroethane is able to reduce the amount of hydrogen fluoride.

Brands[編集]

ECARO-25 is a registered trademark of Fike Corporation. FE-25 is a registered trademark of E. I. du Pont de Nemours and Company or its affiliates. NAF S 125 (HFC-125 plus Acid Scavenging Additive) is a trademark of Safety Hi-Tech.

脚注[編集]

^ Kirk-Othmer Encyclopedia of Chemical Technology. Wiley. ISBN 9780471238966
^ epa.gov reported GWP, published Mar-2006
^ Fike ECARO-25 Product Page
^ Montreal Protocol Section 1.1. including 2016 Kigali amendment (in effect in 2019)
^ P. Forster; V. Ramaswamy; P. Artaxo; T. Berntsen; R. Betts; D.W. Fahey; J. Haywood; J. Lean et al. (2007). “Chapter 2: Changes in Atmospheric Constituents and in Radiative Forcing”. In Solomon, S.; Miller, H.L.; Tignor, M. et al. (英語). Climate Change 2007: The Physical Science Basis. Contribution of Working Group I to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change. Cambridge, United Kingdom and New York, NY, USA: Cambridge University Press 2016年10月9日閲覧。

外部リンク[編集]

Safety MSDS data

[Yaws-1] Kirk-Othmer Encyclopedia of Chemical Technology. Wiley. ISBN 9780471238966

[2] .gov reported GWP, published Mar-2006

[3] Fike ECARO-25 Product Page

[4] Montreal Protocol Section 1.1. including 2016 Kigali amendment (in effect in 2019)

[AR4-5] P. Forster; V. Ramaswamy; P. Artaxo; T. Berntsen; R. Betts; D.W. Fahey; J. Haywood; J. Lean et al. (2007). “Chapter 2: Changes in Atmospheric Constituents and in Radiative Forcing”. In Solomon, S.; Miller, H.L.; Tignor, M. et al. (英語). Climate Change 2007: The Physical Science Basis. Contribution of Working Group I to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change. Cambridge, United Kingdom and New York, NY, USA: Cambridge University Press 2016年10月9日閲覧。

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