Hexachloroethane - Misplaced Pages

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Hexachloroethane
Names


Preferred IUPAC name Hexachloroethane
Other names Carbon hexachloride, Ethane hexachloride, Perchloroethane, Sesquichloride of carbon
Identifiers
CAS Number	67-72-1
3D model (JSmol)	Interactive image
Beilstein Reference	1740341
ChEBI	CHEBI:39227
ChEMBL	ChEMBL160929
ChemSpider	5979
ECHA InfoCard	100.000.606
EC Number	200-666-4
Gmelin Reference	26648
KEGG	C19248
PubChem CID	6214
UNII	G30K3QQT4J
CompTox Dashboard (EPA)	DTXSID7020689
InChI InChI=1S/C2Cl6/c3-1(4,5)2(6,7)8Key: VHHHONWQHHHLTI-UHFFFAOYSA-N InChI=1/C2Cl6/c3-1(4,5)2(6,7)8Key: VHHHONWQHHHLTI-UHFFFAOYAD
SMILES ClC(Cl)(Cl)C(Cl)(Cl)Cl
Properties
Chemical formula	C₂Cl₆
Molar mass	236.74 g/mol
Appearance	colorless crystals
Odor	camphor-like
Density	2.091 g/mL at 25 °C
Melting point	sublimes
Boiling point	183 to 185 °C (361 to 365 °F; 456 to 458 K)
Solubility in water	0.005% (22.2 °C)
Vapor pressure	0.2 mmHg (20 °C)
Magnetic susceptibility (χ)	-112.7·10 cm/mol
Hazards
Occupational safety and health (OHS/OSH):
Main hazards	Probable carcinogen, dangerous CNS depressant
NFPA 704 (fire diamond)	2 0 0
Flash point	noncombustible
Lethal dose or concentration (LD, LC):
LD₅₀ (median dose)	4460 mg/kg (rat, oral) 4970 mg/kg (guinea pig, oral)
NIOSH (US health exposure limits):
PEL (Permissible)	TWA 1 ppm (10 mg/m)
REL (Recommended)	Ca TWA 1 ppm (10 mg/m)
IDLH (Immediate danger)	Ca
Except where otherwise noted, data are given for materials in their standard state (at 25 °C , 100 kPa). N verify (what is ?) Infobox references

Chemical compound

Hexachloroethane (perchloroethane) is an organochlorine compound with the chemical formula (CCl₃)₂. It is a white or colorless solid at room temperature with a camphor-like odor. It has been used by the military in smoke compositions, such as base-eject smoke munitions (smoke grenades).

Hexachloroethane was discovered along with carbon tetrachloride by Michael Faraday in 1820. Faraday obtained it by chlorinating ethylene.

Manufacture

Chlorination of tetrachloroethylene at 100–140 °C with the presence of ferric chloride is the most commonly used commercial production method, however several other methods exist. A high purity form can be produced in a small scale by reacting chlorine together with barium carbide. In September 1997, it was reported as no longer being produced in the United States for commercial distribution, but was produced as a by-product of industrial chlorination process.

Applications

Hexachloroethane has been used in the formulation of extreme pressure lubricants. It has also been used as a chain transfer agent in the emulsion polymerization of propylene–tetrafluoroethylene copolymer. Hexachloroethane has been used as an anthelmintic in veterinary medicine (under the tradename Avlothane), a rubber accelerator, a component of fungicidal and insecticidal formulations as well as a moth repellant and a plasticizer for cellulose esters.

Hexachloroethane has been used in the manufacture of degassing pellets to remove hydrogen gas bubbles from molten aluminum in aluminum foundries. This use, as well as similar uses in magnesium, is being phased out in the European Union.

Use as smoke agent

Smoke grenades, called hexachloroethane smoke or HC smoke, utilize a mixture containing roughly equal parts of hexachloroethane and zinc oxide and approximately 6% granular aluminium. These smokes are toxic, which is attributed to the production of zinc chloride (ZnCl₂). According to Steinritz et al., "Due to its potential pulmonary toxicity," zinc chloride producing smoke grenades "have been discharged from the armory of most western countries (...)."

Use as a riot control agent

Most documented uses of HC smoke as a riot control agent have occurred in the United States; its purchase towards that end has occurred in Milwaukee, Denver and Portland.

Federal Protective Services (FPS) and forces from the Department of Homeland Security are believed to have used HC smoke grenades against protesters during various protests in 2020. At the time, journalists photographed numerous smoke canisters labeled "HC", and measured unusually high levels of zinc and chloride in the area. However, FPS communications director Rob Sperling has denied the use of HC smoke, arguing that, of the two organizations, "FPS doesn't have any items that contain HC."

Toxicity

Hexachloroethane is not particularly toxic when taken orally, but is considered to be quite toxic by skin adsorption. The primary effect is depression of the central nervous system. The concentration that is immediately dangerous to life or health is 300 ppm and the permissible exposure limit according to the Occupational Safety and Health Administration is 1 ppm (skin). It is reasonably anticipated to be a carcinogen.