Chloroethane

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Chloroethane

General
Systematic name Chloroethane
Other names Ethyl chloride
Monochloroethane
Chlorene
EtCl
UN 1037
Molecular formula C2H5Cl
SMILES CCCl
Molar mass 64.51 g mol−1
Appearance colourless gas
CAS number [75-00-3]
Properties
Density and phase 0.92 g cm−3, liquid
Solubility in water 0.6 g/100 ml (?°C)
Melting point −139°C (134 K)
Boiling point 12.3°C (285.4 K)
Acidity (pKa)  ?
Basicity (pKb)  ?
Viscosity  ? cP at ?°C
Structure
Molecular shape tetrahedral (sp3) at carbon
Dipole moment 2.06 D
Hazards
MSDS External MSDS
Main hazards Flammable
NFPA 704

4
2
2
 
Flash point −50°C (closed cup)
R/S statement R: R12, R40, R52, R53
S: S9, S16, S33, S36, S37, S61
RTECS number KH7525000
Supplementary data page
Structure and
properties
n, εr, etc.
Thermodynamic
data
Phase behaviour
Solid, liquid, gas
Spectral data UV, IR, NMR, MS
Related compounds
Related haloalkanes

1,1-dichloroethane
1,2-dichloroethane
1,1,1-trichloroethane
1,1,2-trichloroethane
bromoethane
chloromethane

Except where noted otherwise, data are given for
materials in their standard state (at 25°C, 100 kPa)
Infobox disclaimer and references

Chloroethane or monochloroethane, commonly known by its old name ethyl chloride, is a chemical compound once widely used in producing tetra-ethyl lead, a gasoline additive. It is a colorless, flammable gas or refrigerated liquid with a faintly sweet odor.

Contents

[edit] Production

Ethyl chloride is produced by reacting ethylene and hydrogen chloride over an aluminium chloride catalyst at temperatures ranging from 130-250°C. Under these conditions, ethyl chloride is produced according to the chemical equation.

C2H4 + HCl → C2H5Cl

At various times in the past, ethyl chloride has also been produced from ethanol and hydrochloric acid, or from ethane and chlorine, but these routes are no longer economical. Some ethyl chloride is generated as a byproduct of polyvinyl chloride production. Should demand for ethyl chloride continue to fall to the point where making it for its own sake is not economical, this may become the leading source of the chemical.

[edit] Uses

Beginning in 1922 and continuing through most of the 20th century, the major use of ethyl chloride was to produce tetraethyl lead (TEL), an anti-knock additive for gasoline. However, due to growing awareness of air pollution, TEL has been or is being phased out in most of the industrialized world, and the demand for ethyl chloride has fallen sharply.

Like other chlorinated hydrocarbons, ethyl chloride has been used as a refrigerant, an aerosol spray propellant, an anesthetic, and a blowing agent for foam packaging. At present though, it is not widely used in any of these roles.

The only remaining industrially important use of ethyl chloride is in treating cellulose to make ethylcellulose, a thickening agent and binder in paints, cosmetics, and similar products.

Ethyl chloride is a prescription drug in the US, supplied as a liquid in a spray bottle propelled by its own vapor pressure. It acts as a mild topical anesthetic by its chilling effect when sprayed on skin, such as when removing splinters in a clinical setting. The heat absorbed by the boiling liquid on tissues produces a deep and rapid chill, but since the boiling point is well above freezing, it presents no danger of frostbite. The vapor is flammable and narcotic, which requires care.

Ethyl chloride is a narcotic inhalant drug, sometimes referred to as "Duster". Similar to poppers, ethyl chloride is used as an inhalant (huffed) during sexual activity for an intense several-minute-long high that results in a prolonged orgasm. In Brazil, it is a traditional (though illegal) drug taken during Carnaval parades, known as "lança-perfume".

[edit] Safety

Ethyl chloride is the least toxic of the chloroethanes. Like other chlorinated hydrocarbons, it is a central nervous system depressant, albeit a less potent one than many similar compounds. People breathing its vapors at less than 1% concentration in air usually experience no symptoms. At higher concentrations, victims usually exhibit symptoms similar to those of alcohol intoxication. Breathing its vapors at 15% or higher is often fatal.

Studies on the effects of chronic ethyl chloride exposure in animals have given inconsistent results, and there exists no data for its long-term effects on humans. Some studies have reported that prolonged exposure can produce liver or kidney damage, or uterine cancer in mice, but these data have been difficult to reproduce.

Recent information suggests carcinogenic potential; it has been designated as IARC category A3, Confirmed Animal Carcinogen with Unknown Relevance to Humans. As a result, the State of California has incorporated it into Proposition 65 as a known carcinogen. Nonetheless, it is still used in medicine as a local anesthetic.

[edit] External links