 | |
 | |
| Names | |
|---|---|
| Preferred IUPAC name Hexachloroethane | |
Other names
| |
| Identifiers | |
| |
3D model (JSmol) | |
| 1740341 | |
| ChEBI | |
| ChEMBL | |
| ChemSpider |
|
| ECHA InfoCard | 100.000.606 |
| EC Number |
|
| 26648 | |
| KEGG |
|
| UNII | |
| |
| |
| Properties | |
| C2Cl6 | |
| Molar mass | 236.72 g·mol−1 |
| Appearance | colorless crystals[1] |
| Odor | camphor-like[1] |
| 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) |
| 0.005% (22.2 °C)[1] | |
| Vapor pressure | 0.2 millimetres of mercury (27 Pa) (20 °C)[1] |
| −112.7·10−6 cm3/mol | |
| Hazards | |
| Occupational safety and health (OHS/OSH): | |
Main hazards | Probablecarcinogen, dangerous central nervous system depressant |
| NFPA 704 (fire diamond) | |
| Flash point | noncombustible[1] |
| 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/m3) [skin][1] |
REL (Recommended) | Ca TWA 1 ppm (10 mg/m3) [skin][1] |
IDLH (Immediate danger) | Ca [300 ppm][1] |
| Related compounds | |
Related compounds | |
Except where otherwise noted, data are given for materials in theirstandard state (at 25 °C [77 °F], 100 kPa). | |
Hexachloroethane (perchloroethane) is anorganochlorine compound with thechemical formulaC2Cl6. Its structure isCl3C−CCl3. It is a white or colorless solid at room temperature with acamphor-like odor.[3] It has been used by the military insmoke compositions, such as base-ejectsmoke munitions (smoke grenades).
Hexachloroethane was discovered along withcarbon tetrachloride byMichael Faraday in 1820. Faraday obtained it by chlorinatingethylene. He named it "perchloride of carbon".[4]Faustino Malaguti obtained hexachloroethane by exposing a mixture of tetrachloroethylene andchlorine to sunlight. He termed it "chloride of chlorethose" as it was produced by the chlorination of tetrachloroethylene (then known as "chlorethose").[5]
Chlorination oftetrachloroethylene at 100–140 °C with the presence ofiron(III) 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 withbarium carbide.[6] 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.[6]
Hexachloroethane has been used in the formulation of extreme pressurelubricants. It has also been used as achain transfer agent in theemulsion polymerization of propylene–tetrafluoroethylene copolymer. Hexachloroethane has been used as ananthelmintic inveterinary medicine (under the tradenameAvlothane), a rubber accelerator, a component of fungicidal and insecticidal formulations as well as a moth repellant and a plasticizer for cellulose esters.[3]
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 inmagnesium, is being phased out in theEuropean Union.[7]
Smoke grenades, called hexachloroethane smoke or HC smoke, utilize a mixture containing roughly equal parts of hexachloroethane andzinc oxide and approximately 6% granularaluminium. These smokes are toxic, which is attributed to the production ofzinc chloride (ZnCl2).[8][9] 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 (…).”[10] HC smoke inhalation can cause severeacute respiratory distress syndrome.[11][12][13] The chemical is a suspected carcinogen, has effects on the nervous system,[14] and can cause sudden collapse and death at high doses.[15] TheUnited States Naval Academy considers it achemical weapon.[16] It is also considered a "Type 2" pulmonary agent[17] and a lung-damaging agent.[18]
In 2020, US federal agents inPortland, Oregon used canisters of HC gas against protestors.[19]
Hexachloroethane has relatively low acute oral toxicity, with anmedian lethal dose (LD50) greater than 5000 mg/kg in rats,[20] but is readily absorbed through the skin.[9][21] The primary effect of exposure is depression of thecentral nervous system.[20][3] Acute inhalation exposure may cause coughing and breathing difficulty, with toxic effects potentially delayed up to 24 hours.[20]Occupational exposure limits are typically set at 1 ppm (10 mg/m³) as an 8-hour time-weighted average, with skin notations in the United States, Canada, and international guidelines indicating that dermal absorption contributes significantly to overall exposure.[20][21] The concentration immediately dangerous to life or health is 300 ppm.[21]
Hexachloroethane is suspected of causing cancer and may cause organ damage through prolonged or repeated exposure.[20] TheInternational Agency for Research on Cancer classifies it as Group 2B (possibly carcinogenic to humans), and the U.S.National Toxicology Program lists it as reasonably anticipated to be a human carcinogen.[22]The compound is highly toxic to aquatic life and maybioaccumulate in organisms, posing long-term risks to aquatic environments.[20]
{{cite book}}:ISBN / Date incompatibility (help)| International | |
|---|---|
| National | |