Hexachloroethane

Last updated
Hexachloroethane
Hexachloroethane-2D-stereo.png
Hexachloroethane-3D-balls.png
Names
Preferred IUPAC name
Hexachloroethane
Other names
Carbon hexachloride, Ethane hexachloride, Perchloroethane, Sesquichloride of carbon
Identifiers
3D model (JSmol)
1740341
ChEBI
ChEMBL
ChemSpider
ECHA InfoCard 100.000.606 OOjs UI icon edit-ltr-progressive.svg
EC Number
  • 200-666-4
26648
KEGG
PubChem CID
UNII
  • InChI=1S/C2Cl6/c3-1(4,5)2(6,7)8 Yes check.svgY
    Key: VHHHONWQHHHLTI-UHFFFAOYSA-N Yes check.svgY
  • InChI=1/C2Cl6/c3-1(4,5)2(6,7)8
    Key: VHHHONWQHHHLTI-UHFFFAOYAD
  • ClC(Cl)(Cl)C(Cl)(Cl)Cl
Properties
C2Cl6
Molar mass 236.74 g/mol
Appearancecolorless 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 mmHg (20 °C) [1]
-112.7·10−6 cm3/mol
Hazards
Occupational safety and health (OHS/OSH):
Main hazards
Probable carcinogen, dangerous CNS depressant
NFPA 704 (fire diamond)
NFPA 704.svgHealth 2: Intense or continued but not chronic exposure could cause temporary incapacitation or possible residual injury. E.g. chloroformFlammability 0: Will not burn. E.g. waterInstability 0: Normally stable, even under fire exposure conditions, and is not reactive with water. E.g. liquid nitrogenSpecial hazards (white): no code
2
0
0
Flash point noncombustible [1]
Lethal dose or concentration (LD, LC):
4460 mg/kg (rat, oral)
4970 mg/kg (guinea pig, oral)

[2]

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]
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
X mark.svgN  verify  (what is  Yes check.svgYX mark.svgN ?)

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. [3] It has been used by the military in smoke compositions, such as base-eject smoke munitions (smoke grenades).

Contents

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. [4] :101 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. [4] :101

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, 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 in magnesium, is being phased out in the European Union. [5]

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). [6] [7] 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 (...)." [8]

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. [9]

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. [10] 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." [11]

Toxicity

Hexachloroethane is not particularly toxic when taken orally, [12] but is considered to be quite toxic by skin adsorption. The primary effect is depression of the central nervous system. [3] 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). [12] It is reasonably anticipated to be a carcinogen. [13]

Related Research Articles

<span class="mw-page-title-main">Tetrachloroethylene</span> Chemical compound in very wide use

Tetrachloroethylene, also known under the systematic name tetrachloroethene, or perchloroethylene, and abbreviations such as "perc" (or "PERC"), and "PCE", is a chlorocarbon with the formula Cl2C=CCl2. It is a colorless liquid widely used for dry cleaning of fabrics, hence it is sometimes called "dry-cleaning fluid". It also has its uses as an effective automotive brake cleaner. It has a mild sweet, sharp odor, detectable by most people at a concentration of 1 part per million (1 ppm).

<span class="mw-page-title-main">Phenacyl chloride</span> Chemical compound

Phenacyl chloride, also commonly known as chloroacetophenone, is a substituted acetophenone. It is a useful building block in organic chemistry. Apart from that, it has been historically used as a riot control agent, where it is designated CN. It should not be confused with cyanide, another agent used in chemical warfare, which has the chemical structure CN. Chloroacetophenone is thermally stable, and is the only tear agent that is distillable at ambient conditions.

Monomethylhydrazine is a highly toxic, volatile hydrazine derivative with the chemical formula CH6N2. It is used as a rocket propellant in bipropellant rocket engines because it is hypergolic with various oxidizers such as nitrogen tetroxide and nitric acid. As a propellant, it is described in specification MIL-PRF-27404.

<span class="mw-page-title-main">Chloroethane</span> Chemical compound commonly known as ethyl chloride

Chloroethane, commonly known as ethyl chloride, is a chemical compound with chemical formula CH3CH2Cl, once widely used in producing tetraethyllead, a gasoline additive. It is a colorless, flammable gas or refrigerated liquid with a faintly sweet odor.

<span class="mw-page-title-main">Cyclohexanol</span> Chemical compound

Cyclohexanol is the organic compound with the formula HOCH(CH2)5. The molecule is related to cyclohexane by replacement of one hydrogen atom by a hydroxyl group. This compound exists as a deliquescent colorless solid with a camphor-like odor, which, when very pure, melts near room temperature. Millions of tonnes are produced annually, mainly as a precursor to nylon.

<span class="mw-page-title-main">Smoke screen</span> Airborne obscurant using gas and particulates

A smoke screen is smoke released to mask the movement or location of military units such as infantry, tanks, aircraft, or ships.

<span class="mw-page-title-main">Immediately dangerous to life or health</span> Exposure to dangerous levels of airborne contaminants

The term immediately dangerous to life or health (IDLH) is defined by the US National Institute for Occupational Safety and Health (NIOSH) as exposure to airborne contaminants that is "likely to cause death or immediate or delayed permanent adverse health effects or prevent escape from such an environment." Examples include smoke or other poisonous gases at sufficiently high concentrations. It is calculated using the LD50 or LC50. The Occupational Safety and Health Administration (OSHA) regulation defines the term as "an atmosphere that poses an immediate threat to life, would cause irreversible adverse health effects, or would impair an individual's ability to escape from a dangerous atmosphere."

<span class="mw-page-title-main">Toluene diisocyanate</span> Chemical compound

Toluene diisocyanate (TDI) is an organic compound with the formula CH3C6H3(NCO)2. Two of the six possible isomers are commercially important: 2,4-TDI (CAS: 584-84-9) and 2,6-TDI (CAS: 91-08-7). 2,4-TDI is produced in the pure state, but TDI is often marketed as 80/20 and 65/35 mixtures of the 2,4 and 2,6 isomers respectively. It is produced on a large scale, accounting for 34.1% of the global isocyanate market in 2000, second only to MDI. Approximately 1.4 billion kilograms were produced in 2000. All isomers of TDI are colorless, although commercial samples can appear yellow.

<span class="mw-page-title-main">Ethylbenzene</span> Hydrocarbon compound; precursor to styrene and polystyrene

Ethylbenzene is an organic compound with the formula C6H5CH2CH3. It is a highly flammable, colorless liquid with an odor similar to that of gasoline. This monocyclic aromatic hydrocarbon is important in the petrochemical industry as a reaction intermediate in the production of styrene, the precursor to polystyrene, a common plastic material. In 2012, more than 99% of ethylbenzene produced was consumed in the production of styrene.

<span class="mw-page-title-main">Chloroprene</span> Chemical compound

Chloroprene (IUPAC name 2-chlorobuta-1,3-diene) is a chemical compound with the molecular formula CH2=CCl−CH=CH2. Chloroprene is a colorless volatile liquid, almost exclusively used as a monomer for the production of the polymer polychloroprene, better known as neoprene, a type of synthetic rubber.

<span class="mw-page-title-main">Chlorobenzene</span> Aromatic organochlorine compound

Chlorobenzene is an aryl chloride and the simplest of the chlorobenzenes, consisting of a benzene ring substituted with one chlorine atom. Its chemical formula is C6H5Cl. This colorless, flammable liquid is a common solvent and a widely used intermediate in the manufacture of other chemicals.

The chemical compound 1,2-dichloroethane, commonly known as ethylene dichloride (EDC), is a chlorinated hydrocarbon. It is a colourless liquid with a chloroform-like odour. The most common use of 1,2-dichloroethane is in the production of vinyl chloride, which is used to make polyvinyl chloride (PVC) pipes, furniture and automobile upholstery, wall coverings, housewares, and automobile parts. 1,2-Dichloroethane is also used generally as an intermediate for other organic chemical compounds, and as a solvent. It forms azeotropes with many other solvents, including water and other chlorocarbons.

<span class="mw-page-title-main">Heptachlor</span> Chemical compound

Heptachlor is an organochlorine compound that was used as an insecticide. Usually sold as a white or tan powder, heptachlor is one of the cyclodiene insecticides. In 1962, Rachel Carson's Silent Spring questioned the safety of heptachlor and other chlorinated insecticides. Due to its highly stable structure, heptachlor can persist in the environment for decades. In the United States, the Environmental Protection Agency has limited the sale of heptachlor products to the specific application of fire ant control in underground transformers. The amount that can be present in different foods is regulated.

1,1-Dichloroethene, commonly called 1,1-dichloroethylene or vinylidene chloride or 1,1-DCE, is an organochloride with the molecular formula C2H2Cl2. It is a colorless liquid with a sharp odor. Like most chlorocarbons, it is poorly soluble in water, but soluble in organic solvents. 1,1-DCE was the precursor to the original clingwrap, Saran, for food, but this application has been phased out.

A smoke composition is a pyrotechnic composition designed primarily to generate smoke. Smoke compositions are used as obscurants or for generation of signaling smokes. Some are used as a payload of smoke bombs and smoke grenades.

<span class="mw-page-title-main">Hexachlorobutadiene</span> Chemical compound

Hexachlorobutadiene, (often abbreviated as "HCBD") Cl2C=C(Cl)C(Cl)=CCl2, is a colorless liquid at room temperature that has an odor similar to that of turpentine. It is a chlorinated aliphatic diene with niche applications but is most commonly used as a solvent for other chlorine-containing compounds. Structurally, it has a 1,3-butadiene core, but fully substituted with chlorine atoms.

<span class="mw-page-title-main">Chloroacetaldehyde</span> Chemical compound

Chloroacetaldehyde is an organic compound with the formula ClCH2CHO. Like some related compounds, it is highly electrophilic reagent and a potentially dangerous alkylating agent. The compound is not normally encountered in the anhydrous form, but rather as the hemiacetal (ClCH2CH(OH))2O.

<span class="mw-page-title-main">1,2-Dichloropropane</span> Chemical compound

1,2-Dichloropropane is an organic compound classified as a chlorocarbon. It is a colorless, flammable liquid with a sweet odor. it is obtained as a byproduct of the production of epichlorohydrin, which is produced on a large scale.

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1,2,3-Trichloropropane (TCP) is an organic compound with the formula CHCl(CH2Cl)2. It is a colorless liquid that is used as a solvent and in other specialty applications.

<span class="mw-page-title-main">Perchloromethyl mercaptan</span> Chemical compound

Perchloromethyl mercaptan is the organosulfur compound with the formula CCl3SCl. It is mainly used as an intermediate for the synthesis of dyes and fungicides (captan, folpet). It is a colorless oil, although commercial samples are yellowish. It is insoluble in water but soluble in organic solvents. It has a foul, unbearable, acrid odor. Perchloromethyl mercaptan is the original name. The systematic name is trichloromethanesulfenyl chloride, because the compound is a sulfenyl chloride, not a mercaptan.

References

  1. 1 2 3 4 5 6 7 8 NIOSH Pocket Guide to Chemical Hazards. "#0316". National Institute for Occupational Safety and Health (NIOSH).
  2. "Hexachloroethane". Immediately Dangerous to Life or Health Concentrations (IDLH). National Institute for Occupational Safety and Health (NIOSH).
  3. 1 2 3 Snedecor, Gayle (1999). "Hexachloroethane". In Kroschwitz, Jacqueline I. (ed.). Kirk-Othmer Concise Encyclopedia of Chemical Technology (4th ed.). New York: John Wiley & Sons, Inc. p. 428. ISBN   978-0471419617.
  4. 1 2 "Hexachloroethane 101" (PDF). September 1997.
  5. ECHA, Annex XVII to REACH – Conditions of restriction, Restrictions on the manufacture, placing on the market and use of certain dangerous substances, mixtures and articles, entry 41: hexachloroethane
  6. "Appendix E: Smoke And Masking Agents" (PDF). Australian Department of Veteran Affairs. December 2003. p. E-3. Archived from the original (PDF) on 2014-02-13. Retrieved 2012-10-04.
  7. National Research Council (1997). Toxicity of Military Smokes and Obscurants, volume 1. Subcommittee on Military Smokes and Obscurants. Washington, DC: National Academy Press. p. 127
  8. Steinritz, D., Zehfuß, F., Stenger, B., Schmidt, A., Popp, T., Kehe, K., Mückter, H., Thiermann, H., Gudermann, T. (2018). Zinc chloride-induced TRPA1 activation does not contribute to toxicity in vitro. Toxicology Letters, 293, 133–139. doi:10.1016/j.toxlet.2017.09.008
  9. "Police deployed potentially lethal chemical during Black Lives Matter protests". Salon. 2021-02-21. Retrieved 2021-06-16.
  10. Lerner, Sharon (October 10, 2020). "Toxic Chemical Smoke Grenades Used in Portland". The Intercept. Retrieved 2021-06-16.
  11. "Military-grade HC smoke used against Portland protesters". KOIN.com. 2020-10-20. Retrieved 2021-06-16.
  12. 1 2 "Documentation for Immediately Dangerous To Life or Health Concentrations (IDLHs) Hexachloroethane". NIOSH. May 1994. Retrieved 2012-10-04.
  13. "Report on Carcinogens, Twelfth Edition, Hexachloroethane" (PDF). NIH. 2011. Retrieved 2012-10-04.