Chloroethane

Chloroethane
Identifiers
CAS number 75-00-3 Y
PubChem 6337
ChemSpider 6097 Y
UNII 46U771ERWK Y
KEGG D04088 Y
ChEBI CHEBI:47554 Y
ChEMBL CHEMBL46058 Y
RTECS number KH7525000
Jmol-3D images Image 1
Properties
Molecular formula C2H5Cl
Molar mass 64.51 g/mol
Appearance colourless gas
Density 0.92 g/cm3, liquid
Melting point

−139 °C (134 K)

Boiling point

12.3 °C (285.4 K)

Solubility in water 0.6 g/100 ml (?°C)
Structure
Dipole moment 2.06 D
Hazards
R-phrases R12, R40, R52, R53
S-phrases S9, S16, S33, S36, S37, S61
Main hazards Flammable
NFPA 704
4
2
2
Flash point −50°C (closed cup)
Related compounds
Related haloalkanes 1,1-dichloroethane

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

 Y (verify) (what is: Y/N?)
Except where noted otherwise, data are given for materials in their standard state (at 25 °C, 100 kPa)
Infobox references

Chloroethane or monochloroethane, commonly known by its old name ethyl chloride, is a chemical compound with chemical formula C2H5Cl, once widely used in producing tetraethyllead, a gasoline additive. It is a colorless, flammable gas or refrigerated liquid with a faintly sweet odor.

Contents

Production

Ethyl chloride is produced by hydrochlorination of ethylene:

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.

Uses

Beginning in 1922 and continuing through most of the 20th century, the major use of ethyl chloride was to produce tetraethyllead (TEL), an anti-knock additive for gasoline. TEL has been or is being phased out in most of the industrialized world, and the demand for ethyl chloride has fallen sharply. It also reacts with aluminium metal to give ethylaluminium sesquichloride, a precursor to polymers and other useful organoaluminium compounds.[1]

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. For a time it was used as a promoter chemical in the aluminium chloride catalyzed process to produce ethylbenzene, the precursor for styrene monomer. 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 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 the freezing point of water, it presents no danger of frostbite. The vapor is flammable and narcotic, which requires care.

Ethyl chloride is a recreational inhalant drug, sometimes referred to as "Duster". Similar to poppers, ethyl chloride is used as an inhalant (huffed) during sexual activity. In Brazil, it is a traditional (though illegal) drug taken during Carnaval parades, known as "lança-perfume".

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 exist 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.

Chloroethane is not classifiable as to its carcinogenicity to humans (Group 3).[2]

Recent information suggests carcinogenic potential; it has been designated as ACGIH 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.

References

  1. ^ Krause, M.J., Orlandi, F., Saurage, A.T., Zietz Jr., J.R. Aluminum Compounds. Ullmann's Encyclopedia of Industrial Chemistry. 2000. doi:10.1002/14356007.a01_543
  2. ^ Chloroethane, IARC

External links