1,1,1,2-Tetrafluoroethane (also known as norflurane (
INN
Inns are generally establishments or buildings where travelers can seek lodging, and usually, food and drink. Inns are typically located in the country or along a highway; before the advent of motorized transportation they also provided accommo ...
), R-134a, Freon 134a, Forane 134a, Genetron 134a, Green Gas, Florasol 134a, Suva 134a, or HFC-134a) is a
hydrofluorocarbon
Hydrofluorocarbons (HFCs) are man-made organic compounds that contain fluorine and hydrogen atoms, and are the most common type of organofluorine compounds. Most are gases at room temperature and pressure. They are frequently used in air condi ...
(HFC) and
haloalkane refrigerant with thermodynamic properties similar to
R-12 (dichlorodifluoromethane) but with insignificant
ozone depletion potential
The ozone depletion potential (ODP) of a chemical compound is the relative amount of degradation to the ozone layer it can cause, with trichlorofluoromethane (R-11 or CFC-11) being fixed at an ODP of 1.0. Chlorodifluoromethane (R-22), for exampl ...
and a lower 100-year
global warming potential
Global warming potential (GWP) is the heat absorbed by any greenhouse gas in the atmosphere, as a multiple of the heat that would be absorbed by the same mass of carbon dioxide (). GWP is 1 for . For other gases it depends on the gas and the time ...
(1,430, compared to R-12's GWP of 10,900).
It has the formula CFCHF and a
boiling point of −26.3 °C (−15.34 °F) at atmospheric pressure. R-134a cylinders are colored
light blue
The first use of "light blue" as a color term in English is in the year 1915.
In Russian and some other languages, there is no single word for blue, but rather different words for light blue (, goluboy) and dark blue (, siniy). The ancient Gree ...
. A phaseout and transition to
HFO-1234yf
2,3,3,3-Tetrafluoropropene, HFO-1234yf, is a hydrofluoroolefin (HFO) with the formula CH2=CFCF3.
It is also designated R-1234yf as the first of a new class of refrigerants: it is marketed under the name Opteon YF by Chemours and as Solstice YF ...
and other refrigerants, with GWPs similar to CO
2, began in 2012 within the automotive market.
Uses
1,1,1,2-Tetrafluoroethane is a
non-flammable
A combustible material is something that can burn (i.e., ''combust'') in air. A combustible material is flammable if it ignites easily at ambient temperatures. In other words, a combustible material ignites with some effort and a flammable mat ...
gas used primarily as a "high-temperature" refrigerant for domestic
refrigeration
The term refrigeration refers to the process of removing heat from an enclosed space or substance for the purpose of lowering the temperature.International Dictionary of Refrigeration, http://dictionary.iifiir.org/search.phpASHRAE Terminology, ht ...
and
automobile air conditioners. These devices began using 1,1,1,2-tetrafluoroethane in the early 1990s as a replacement for the more environmentally harmful R-12. Retrofit kits are available to convert units that were originally R-12-equipped.
![Tetrafluoroethane liquid](https://upload.wikimedia.org/wikipedia/commons/b/bd/Tetrafluoroethane_liquid.jpg)
Other common uses include plastic foam blowing, as a cleaning solvent, a propellant for the delivery of pharmaceuticals (e.g.
bronchodilator
A bronchodilator or broncholytic (although the latter occasionally includes secretory inhibition as well) is a substance that dilates the bronchi and bronchioles, decreasing resistance in the respiratory airway and increasing airflow to the lung ...
s), wine cork removers,
gas duster
A gas duster, also known as canned air or compressed air, is a product used for cleaning or dusting electronic equipment and other sensitive devices that cannot be cleaned using water.
This type of product is most often packaged as a can that, ...
s ("canned air"), and in air driers for removing the moisture from
compressed air. 1,1,1,2-Tetrafluoroethane has also been used to cool computers in some
overclocking
In computing, overclocking is the practice of increasing the clock rate of a computer to exceed that certified by the manufacturer. Commonly, operating voltage is also increased to maintain a component's operational stability at accelerated sp ...
attempts. It is the refrigerant used in plumbing pipe freeze kits. It is also commonly used as a propellant for
airsoft
Airsoft is a team game in which participants eliminate opposing players by tagging them out of play with spherical plastic projectiles shot with mock air weapons(usually powered by an electronic motor) called airsoft guns.
Although similar ...
airguns. The gas is often mixed with a silicone-based lubricant.
Aspirational and niche applications
1,1,1,2-Tetrafluoroethane is also being considered as an
organic solvent
A solvent (s) (from the Latin '' solvō'', "loosen, untie, solve") is a substance that dissolves a solute, resulting in a solution. A solvent is usually a liquid but can also be a solid, a gas, or a supercritical fluid. Water is a solvent for ...
, both in liquid and
supercritical fluid.
It is used in the
resistive plate chamber A Resistive plate chamber (RPC) is a particle detector widely used in high energy physics. They are used for detecting muons in most of the modern experiments including ATLAS, CMS, and BES III The Beijing Spectrometer III (BES III) is a particle phy ...
particle detector
In experimental and applied particle physics, nuclear physics, and nuclear engineering, a particle detector, also known as a radiation detector, is a device used to detect, track, and/or identify ionizing particles, such as those produced by nu ...
s in the
Large Hadron Collider. It is also used for other types of particle detectors, e.g. some
cryogenic particle detector Cryogenic particle detectors operate at very low temperature, typically only a few degrees above absolute zero. These sensors interact with an energetic elementary particle (such as a photon) and deliver a signal that can be related to the type of p ...
s. It can be used as an alternative to
sulfur hexafluoride in
magnesium
Magnesium is a chemical element with the symbol Mg and atomic number 12. It is a shiny gray metal having a low density, low melting point and high chemical reactivity. Like the other alkaline earth metals (group 2 of the periodic ta ...
smelting
Smelting is a process of applying heat to ore, to extract a base metal. It is a form of extractive metallurgy. It is used to extract many metals from their ores, including silver, iron, copper, and other base metals. Smelting uses heat and a ...
as a
shielding gas
Shielding gases are inert or semi-inert gases that are commonly used in several welding processes, most notably gas metal arc welding and gas tungsten arc welding (GMAW and GTAW, more popularly known as MIG (Metal Inert Gas) and TIG (Tungsten Iner ...
.
History and environmental impacts
1,1,1,2-Tetrafluoroethane was introduced in the early 1990s as a replacement for dichlorodifluoromethane (R-12), which has massive ozone depleting properties. Even though 1,1,1,2-Tetrafluoroethane has insignificant ozone depletion potential (
ozone layer) and negligible acidification potential (
acid rain), it has a 100-year
global warming potential
Global warming potential (GWP) is the heat absorbed by any greenhouse gas in the atmosphere, as a multiple of the heat that would be absorbed by the same mass of carbon dioxide (). GWP is 1 for . For other gases it depends on the gas and the time ...
(GWP) of 1430 and an approximate
atmospheric lifetime
A greenhouse gas (GHG or GhG) is a gas that Absorption (electromagnetic radiation), absorbs and Emission (electromagnetic radiation), emits radiant energy within the thermal infrared range, causing the greenhouse effect. The primary greenhouse ...
of 14 years.
Its concentration in the atmosphere and contribution to
radiative forcing
Radiative forcing (or climate forcing) is the change in energy flux in the atmosphere caused by natural or anthropogenic factors of climate change as measured by watts / metre2. It is a scientific concept used to quantify and compare the extern ...
have been growing since its introduction. Thus it was included in the
IPCC list of greenhouse gases
This is a list of the most influential long-lived, well-mixed greenhouse gases, along with their tropospheric concentrations and direct radiative forcings, as identified by the Intergovernmental Panel on Climate Change (IPCC). Abundances of thes ...
.
![HFC-134a_mm](https://upload.wikimedia.org/wikipedia/commons/5/5c/HFC-134a_mm.png)
R-134a was consequently banned from use in the European Union, starting with new cars in 2011, by a directive of 2006 banning gases in air conditioning systems with a GWP above 100.
1,1,1,2-tetrafluoroethane is subject to use restrictions in the US and other countries as well. The Society of Automotive Engineers (SAE) has proposed that it be best replaced by a new fluorochemical refrigerant
HFO-1234yf
2,3,3,3-Tetrafluoropropene, HFO-1234yf, is a hydrofluoroolefin (HFO) with the formula CH2=CFCF3.
It is also designated R-1234yf as the first of a new class of refrigerants: it is marketed under the name Opteon YF by Chemours and as Solstice YF ...
(CFCF=CH) in automobile air-conditioning systems. By model year 2021, newly manufactured light-duty vehicles in the United States will no longer use R-134a.
California may also prohibit the sale of canned R-134a to individuals to avoid non-professional recharge of air conditioners. A ban had been in place in Wisconsin since October 1994 under ATCP 136 prohibiting sales of container sizes holding less than 15 lbs of 1,1,1,2-tetrafluoroethane, but this restriction applied only when the chemical was intended to be a refrigerant. However, the ban was lifted in Wisconsin in 2012.
[Chapter ATCP 136. MOBILE AIR CONDITIONERS; RECLAIMING OR RECYCLING REFRIGERANT](_blank)
State.wi.us. (PDF). Retrieved 21 August 2011. During the time that it was active, this Wisconsin-specific ban contained loopholes. For example, it was legal for a person to purchase
gas duster
A gas duster, also known as canned air or compressed air, is a product used for cleaning or dusting electronic equipment and other sensitive devices that cannot be cleaned using water.
This type of product is most often packaged as a can that, ...
containers with any amount of the chemical because in that instance the chemical is neither intended to be a refrigerant
nor is HFC-134a included in the § 7671a listing of class I and class II substances.
Production and reactions
Tetrafluoroethane is typically made by reacting
trichloroethylene
The chemical compound trichloroethylene is a halocarbon commonly used as an industrial solvent. It is a clear, colourless non-flammable liquid with a chloroform-like sweet smell. It should not be confused with the similar 1,1,1-trichloroethane, w ...
with
hydrogen fluoride:
:CHCl=CCl + 4 HF → CFCHF + 3 HCl
It reacts with butyllithium to give trifluorovinyl lithium:
:CFCHF + 2 BuLi → CF=CFLi + LiF + 2 BuH
Safety
![R134a container](https://upload.wikimedia.org/wikipedia/commons/4/4b/R134a_container.png)
Mixtures with air of the gas 1,1,1,2-tetrafluoroethane are not
flammable at atmospheric pressure and temperatures up to 100 °C (212 °F). However, mixtures with high concentrations of air at elevated pressure and/or temperature can be
ignited. Contact of 1,1,1,2-tetrafluoroethane with flames or hot surfaces in excess of 250 °C (482 °F) may cause vapor
decomposition
Decomposition or rot is the process by which dead organic substances are broken down into simpler organic or inorganic matter such as carbon dioxide, water, simple sugars and mineral salts. The process is a part of the nutrient cycle and is e ...
and the emission of
toxic
Toxicity is the degree to which a chemical substance or a particular mixture of substances can damage an organism. Toxicity can refer to the effect on a whole organism, such as an animal, bacterium, or plant, as well as the effect on a subs ...
gases including
hydrogen fluoride and
carbonyl fluoride
Carbonyl fluoride is a chemical compound with the formula COF2. It is a carbon oxohalide. This gas, like its analog phosgene, is colourless and highly toxic. The molecule is planar with ''C''2v symmetry, bond lengths of 1.174 Å (C=O) and 1.312 ...
, however the decomposition temperature has been reported as above 370°C. 1,1,1,2-Tetrafluoroethane itself has an of 1,500 g/m in rats, making it relatively non-toxic, apart from the dangers inherent to
inhalant abuse
Inhalants are a broad range of household and industrial chemicals whose volatile vapors or pressurized gases can be concentrated and breathed in via the nose or mouth to produce intoxication, in a manner not intended by the manufacturer. They ...
. Its gaseous form is denser than air and will displace air in the lungs. This can result in
asphyxia
Asphyxia or asphyxiation is a condition of deficient supply of oxygen to the body which arises from abnormal breathing. Asphyxia causes generalized hypoxia, which affects primarily the tissues and organs. There are many circumstances that ca ...
tion if excessively inhaled. This contributes to most deaths by
inhalant abuse
Inhalants are a broad range of household and industrial chemicals whose volatile vapors or pressurized gases can be concentrated and breathed in via the nose or mouth to produce intoxication, in a manner not intended by the manufacturer. They ...
.
Aerosol cans containing 1,1,1,2-tetrafluoroethane, when inverted, become effective freeze sprays. Under pressure, 1,1,1,2-tetrafluoroethane is compressed into a liquid, which upon vaporization absorbs a significant amount of
thermal energy
The term "thermal energy" is used loosely in various contexts in physics and engineering. It can refer to several different well-defined physical concepts. These include the internal energy or enthalpy of a body of matter and radiation; heat, de ...
. As a result, it will greatly lower the temperature of any object it contacts as it evaporates.
Medical use
For its medical uses, 1,1,1,2-tetrafluoroethane has the
generic name norflurane. It is used as propellant for some metered dose
inhaler
An inhaler (also known as a puffer, pump or allergy spray) is a medical device used for delivering medicines into the lungs through the work of a person's breathing. This allows medicines to be delivered to and absorbed in the lungs, which prov ...
s. It is considered safe for this use.
In combination with
pentafluoropropane
1,1,1,3,3-Pentafluoropropane (HFC-245fa) is a hydrofluorocarbon is a colorless gas used primarily for closed-cell spray foam insulation. HFC-245fa is also known as pentafluoropropane and by its chemical name 1,1,1,3,3-pentafluoropropane.
Environ ...
, it is used as a topical
vapocoolant
Freeze spray (cold spray or vapocoolant) is a type of aerosol spray product containing a liquified gas used for rapidly cooling surfaces, in medical and industrial applications. It is usually sold in hand-held spray cans. It may consist of vario ...
spray for numbing
boil
A boil, also called a furuncle, is a deep folliculitis, which is an infection of the hair follicle. It is most commonly caused by infection by the bacterium '' Staphylococcus aureus'', resulting in a painful swollen area on the skin caused by ...
s before
curettage
Curettage ( or ), in medical procedures, is the use of a curette (French, meaning scoop Mosby's Medical, Nursing & Allied Health Dictionary, Fourth Edition, Mosby-Year Book 1994, p. 422) to remove tissue by scraping or scooping.
Curettages are ...
. It has also been studied as a potential
inhalational anesthetic
An inhalational anesthetic is a chemical compound possessing general anesthetic properties that can be delivered via inhalation. They are administered through a face mask, laryngeal mask airway or tracheal tube connected to an anesthetic vapo ...
,
but it is nonanaesthetic at doses used in inhalers.
[
]
See also
* List of refrigerants
This is a list of refrigerants, sorted by their ASHRAE-designated numbers, commonly known as R numbers. Many modern refrigerants are man-made halogenated gases, especially fluorinated gases and chlorinated gases, that are frequently referred to as ...
* Dichlorodifluoromethane
* 1,1,1,2-Tetrafluoroethane (data page) This page lists chemical and physical properties of 1,1,1,2-tetrafluoroethane.
Vapor Pressure at 25 °C (77 °F) kPa 666.1
bar 6.661
psia 96.61
Heat of Vaporization at Boiling Point kJ/kg 217.2
Btu/lb 93.4
Thermal Conductivity at 25&nb ...
* Tetrabromoethane
Tetrabromoethane (TBE) is a halogenated hydrocarbon, chemical formula C2H2Br4. Although three bromine atoms may bind to one of the carbon atoms creating 1,1,1,2-tetrabromoethane this is not thermodynamically favorable, so in practice tetrabromoeth ...
* Tetrachloroethane Tetrachloroethane may refer to either of two isomeric chemical compounds:
* 1,1,1,2-Tetrachloroethane (R-130a)
* 1,1,2,2-Tetrachloroethane (R-130)
See also
* Tetrachloroethene
* Trichloroethane
* Tetrafluoroethane
* Tetrabromoethane
Tetrabromoet ...
References
External links
*
European Fluorocarbons Technical Committee (EFCTC)
at inchem.org
*
R134a 2 phase computer cooling
{{DEFAULTSORT:Tetrafluoroethane, 1, 1, 1, 2-
Fluoroalkanes
Refrigerants
Automotive chemicals
Propellants
Airsoft
Excipients
Greenhouse gases
GABAA receptor positive allosteric modulators
General anesthetics