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| Names | |||
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| Preferred IUPAC name Tetrachloromethane | |||
| Other names Benzinoform carbon(IV) chloride carbon tet Carboneum Tetrachloratum / Carbonei tetrachloridum Carboneum Chloratum / Carbonei chlorurum chloride of carbon Freon-10 Halon-104 methane tetrachloride methyl tetrachloride Necatorina perchloromethane Refrigerant-10 Tetrachloretum Carbonicum Tetrachlorocarbon Tetraform Tetrasol | |||
| Identifiers | |||
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3D model (JSmol) | |||
| Abbreviations | CTC, TCM, PCM, R-10 | ||
| 1098295 | |||
| ChEBI | |||
| ChEMBL | |||
| ChemSpider |
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| ECHA InfoCard | 100.000.239 | ||
| EC Number |
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| 2347 | |||
| KEGG |
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| RTECS number |
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| UNII | |||
| UN number | 1846 | ||
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| Properties | |||
| CCl4 | |||
| Molar mass | 153.81 g·mol−1 | ||
| Appearance | Colourless liquid | ||
| Odor | chloroform-like odor | ||
| Density |
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| Melting point | −22.92 °C (−9.26 °F; 250.23 K) | ||
| Boiling point | 76.72 °C (170.10 °F; 349.87 K) | ||
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| Solubility | Soluble inalcohol,ether,chloroform,benzene,naphtha,CS2,formic acid | ||
| logP | 2.64 | ||
| Vapor pressure | 11.94 kPa at 20 °C | ||
Henry's law constant (kH) | 2.76×10−2 atm·m3/mol | ||
| −66.60×10−6 cm3/mol | |||
| Thermal conductivity | 0.1036 W/m·K (300 K)[1] | ||
Refractive index (nD) | 1.4607 | ||
| Viscosity | 0.86 mPa·s[2] | ||
| 0 D | |||
| Structure | |||
| Monoclinic | |||
| Tetragonal | |||
| Tetrahedral | |||
| 0 D | |||
| Thermochemistry | |||
| 132.6 J/mol·K | |||
Std molar entropy(S⦵298) | 214.39 J/mol·K | ||
Std enthalpy of formation(ΔfH⦵298) | −95.6 kJ/mol | ||
Gibbs free energy(ΔfG⦵) | −87.34 kJ/mol[3] | ||
| Hazards | |||
| Occupational safety and health (OHS/OSH): | |||
Main hazards | extremely toxic to the liver and kidneys, potential occupational carcinogen, harmful to theozone layer | ||
| GHS labelling: | |||
  | |||
| Danger | |||
| H301,H302,H311,H331,H351,H372,H412,H420 | |||
| P201,P202,P260,P261,P264,P270,P271,P273,P280,P281,P301+P310,P302+P352,P304+P340,P308+P313,P311,P312,P314,P321,P322,P330,P361,P363,P403+P233,P405,P501,P502 | |||
| NFPA 704 (fire diamond) | |||
| Flash point | non-flammable | ||
| Lethal dose or concentration (LD, LC): | |||
LD50 (median dose) | 7749 mg/kg (oral, mouse); 5760 mg/kg (oral, rabbit); 2350 mg/kg (oral, rat)[5] | ||
LC50 (median concentration) |
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LCLo (lowest published) |
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| NIOSH (US health exposure limits): | |||
PEL (Permissible) | TWA 10 ppm C 25 ppm 200 ppm (5-minute maximum peak in any 4 hours)[4] | ||
REL (Recommended) | Ca ST 2 ppm (12.6 mg/m3) [60-minute][4] | ||
IDLH (Immediate danger) | 200 ppm[4] | ||
| Safety data sheet (SDS) | ICSC 0024 | ||
| Related compounds | |||
Otheranions | Carbon tetrafluoride Carbon tetrabromide Carbon tetraiodide | ||
Othercations | Silicon tetrachloride Germanium tetrachloride Tin tetrachloride Lead tetrachloride | ||
Related chloromethanes | Chloromethane Dichloromethane Trichloromethane | ||
| Supplementary data page | |||
| Carbon tetrachloride (data page) | |||
Except where otherwise noted, data are given for materials in theirstandard state (at 25 °C [77 °F], 100 kPa). | |||
Carbon tetrachloride, also known by many other names (such ascarbon tet for short andtetrachloromethane, alsorecognised by the IUPAC), is achemical compound with thechemical formula CCl4. It is a volatile, non-flammable, dense, colourless liquid with achloroform-like sweet odour that can be detected at low levels. It was formerly widely used infire extinguishers, as a precursor torefrigerants, ananthelmintic and acleaning agent, but has since been phased out because of environmental and safety concerns. Exposure to high concentrations of carbon tetrachloride can affect thecentral nervous system and degenerate the liver and kidneys. Prolonged exposure can be fatal.
In the carbon tetrachloridemolecule, fourchlorineatoms are positioned symmetrically as corners in atetrahedral configuration joined to a centralcarbon atom by singlecovalent bonds. Because of this symmetric geometry, CCl4 is non-polar.Methane gas has the same structure, making carbon tetrachloride ahalomethane. As asolvent, it is well suited to dissolving other non-polar compounds such as fats and oils. It can also dissolveiodine. It isvolatile, giving offvapors with an odor characteristic of other chlorinated solvents, somewhat similar to thetetrachloroethylene odor reminiscent ofdry cleaners' shops.
Solid tetrachloromethane has twopolymorphs: crystalline II below −47.5°C (225.6 K) and crystalline I above −47.5°C.[7] At −47.3°C it hasmonoclinic crystal structure with space groupC2/c andlattice constantsa = 20.3,b = 11.6,c = 19.9 (.10−1 nm), β = 111°.[8]
With aspecific gravity greater than 1, carbon tetrachloride will be present as adense nonaqueous phase liquid if sufficient quantities are spilt in the environment.
Despite being generally inert, carbon tetrachloride can undergo various reactions. Hydrogen or an acid in the presence of aniron catalyst can reduce carbon tetrachloride to chloroform, dichloromethane, chloromethane and even methane.[9] When its vapours are passed through a red-hot tube, carbon tetrachloride dechlorinates totetrachloroethylene andhexachloroethane.[10]
Carbon tetrachloride, when treated withHF, gives various compounds such astrichlorofluoromethane (R-11),dichlorodifluoromethane (R-12),chlorotrifluoromethane (R-13) andcarbon tetrafluoride withHCl as the by-product:
This was once one of the main uses of carbon tetrachloride, as R-11 and R-12 were widely used as refrigerants.
An alcohol solution of potassium hydroxide decomposes it to potassium chloride and potassium carbonate in water:[11]
Carbon is sufficientlyoxophilic that many compounds react to givephosgene:
| Reactants | Products | Conditionscite | |
|---|---|---|---|
| CO2 + CCl4 | → | 2 COCl2 | 350°C[12] |
| CO + CCl4 | → | COCl2 +1⁄3C2Cl4 | [12] |
| 2SO3 + CCl4 | → | COCl2 +(SO2Cl)2O | [13] |
| 1⁄3P2O5 + CCl4 | → | COCl2 +2⁄3POCl3 | [13] |
| 3ZnO + 2 CCl4 | → | COCl2 + CO2 + 3ZnCl2 | ZnO dry; 200°C[12] |
Reaction withhydrogen sulfide givesthiophosgene:[13]
Carbon tetrachloride was originally synthesized in 1820 byMichael Faraday, who named it "protochloride of carbon", by decomposition ofhexachloroethane ("perchloride of carbon") which he synthesized by chlorination ofethylene.[14][15] The protochloride of carbon has been previously misidentified astetrachloroethylene because it can be made with the same reaction of hexachloroethane. Later in the 19th century, the name "protochloride of carbon" was used for tetrachloroethylene, and carbon tetrachloride was called "bichloride of carbon" or "perchloride of carbon".Henri Victor Regnault developed another method to synthesise carbon tetrachloride fromchloroform,chloroethane ormethanol with excesschlorine in 1839.[16]
Kolbe made carbon tetrachloride in 1845 by passing chlorine over carbon disulfide through a porcelain tube.[16] Prior to the 1950s, carbon tetrachloride was manufactured by the chlorination ofcarbon disulfide at 105 to 130 °C:[17]
But now it is mainly produced frommethane:
The production often utilizes by-products of otherchlorination reactions, such as from the syntheses ofdichloromethane andchloroform. Higher chlorocarbons are also subjected to this process named "chlorinolysis":
The production of carbon tetrachloride has steeply declined since the 1980s because of environmental concerns and the decreased demand forCFCs, which were derived from carbon tetrachloride. In 1992, production in the U.S./Europe/Japan was estimated at 720,000 tonnes.[17] In the 2010s, the total amount of CCl4 produced and imported into the US annually was under 70,000 tonnes.[18]
Carbon tetrachloride was discovered along with chloromethane and chloroform inoceans,marine algae andvolcanoes.[19] Natural emissions of carbon tetrachloride are insignificant compared to anthropogenic sources; for example, theMomotombo volcano inNicaragua emits carbon tetrachloride at aflux of 82 grams per year while the global industrial emissions were at 2 × 1010 grams per year.[20]
Carbon tetrachloride was found inred algae, specificallyAsparagopsis taxiformis andAsparagopsis armata.[21] It was detected inSouthern Californian ecosystems,salt lakes of theKalmykian steppe and a commonliverwort in theCzech Republic.[20]
At high temperatures in air, it decomposes or burns to produce poisonousphosgene. This was a common problem when carbon tetrachloride was used as a fire extinguisher[22] and there have been deaths due to its conversion to phosgene reported.[23]
Carbon tetrachloride is a suspected humancarcinogen but there is no sufficient evidence of carcinogenicity in humans.[24] TheWorld Health Organization reports carbon tetrachloride can inducehepatocellular carcinomas (hepatomas) in mice and rats. The doses inducing hepatic tumors in mice and rats are higher than those inducing cell toxicity.[25] TheInternational Agency for Research on Cancer (IARC) classified this compound inGroup 2B, "possibly carcinogenic to humans".[26]
Carbon tetrachloride is one of the most potenthepatotoxins (toxic to the liver), so much so that it is widely used in scientific research to evaluate hepatoprotective agents.[27][28] Exposure to high concentrations of carbon tetrachloride (including vapor) can affect thecentral nervous system and degenerate the liver[28] and kidneys,[29] and prolonged exposure may lead tocoma or death.[30] Chronic exposure to carbon tetrachloride can causeliver[31][32] andkidney damage and could result incancer.[33][34]
Consumption ofalcohol increases the toxic effects of carbon tetrachloride and may cause more severe organ damage, such asacute renal failure, in heavy drinkers. The doses that can cause mild toxicity to non-drinkers can be fatal to drinkers.[35]
The effects of carbon tetrachloride on human health and the environment have been assessed underREACH in 2012 in the context of the substance evaluation by France.[36]
In 2008, a study of common cleaning products found the presence of carbon tetrachloride in "very high concentrations" (up to 101 mg/m3) as a result of manufacturers' mixing of surfactants or soap withsodium hypochlorite (bleach).[37]
Carbon tetrachloride is also bothozone-depleting[38] and agreenhouse gas.[39] However, since 1992[40] its atmospheric concentrations have been in decline for the reasons described above (see atmospheric concentration graphs in thegallery). CCl4 has anatmospheric lifetime of 85 years.[41]
Prior to being phased out due to toxicity and environmental impact, carbon tetrachloride was widely used as adry cleaning solvent, as arefrigerant, and inlava lamps.[42] In the last case, carbon tetrachloride is a key ingredient that adds weight to the otherwise buoyant wax.
One speciality use of carbon tetrachloride was instamp collecting, to revealwatermarks on postage stamps without damaging them. A small amount of the liquid is placed on the back of a stamp, sitting in a black glass or obsidian tray. The letters or design of the watermark can then be seen clearly. Today, this is done on lit tables without using carbon tetrachloride.
Inorganic chemistry, carbon tetrachloride serves as a source of chlorine in theAppel reaction.
Carbon tetrachloride made from heavychlorine-37 has been used in the detection ofneutrinos andantineutrinos.Raymond Davis Jr. used carbon tetrachloride in his experiments to detect antineutrinos.[43]
Being a good solvent for many materials (such as grease and tar), carbon tetrachloride was widely used as a cleaning fluid for nearly 70 years. It is nonflammable and nonexplosive and did not leave any odour on the cleaned material, unlikegasoline, which was also used for cleaning at the time. It was used as a "safe" alternative to gasoline. It was first marketed asKatharin, in the early 1890s[44][45] and asBenzinoform later.
Carbon tetrachloride was recommended for regularly cleaning the type slugs oftypewriters in office settings in the 1940s.[46]
Carbon tetrachloride was the first chlorinated solvent to be used indry-cleaning and was used until the 1950s.[47] It had the downsides of being corrosive to the dry-cleaning equipment and causing illness among dry-cleaning operators, and was replaced by less toxic and overall safer solvents such astrichloroethylene,tetrachloroethylene[47] andmethyl chloroform (trichloroethane).[48]
Carbon tetrachloride was also used as an ingredient indry shampoos due to its solvent properties and quick evaporation from 1903 until the 1930s, when it was discontinued due to health and safety concerns. Several women had fainted from its fumes during the hair wash at the hairdressers, andelectric fans were used to blow the fumes away. In 1909, abaronet's 29-year-old daughter, HelenoraElphinstone-Dalrymple, died after having her hair shampooed with carbon tetrachloride.[49][50]
It is assumed that carbon tetrachloride was still used as a dry cleaning solvent inNorth Korea as of 2006.[51]
Carbon tetrachloride was briefly used as a volatile inhalation anaesthetic and analgesic for intensemenstruation pains and headaches in the mid-19th century.[52] Its anaesthetic effects were known as early as 1847 or 1848.[53][54]
It was introduced as a safer alternative tochloroform by the doctor Protheroe Smith in 1864.[55] In December 1865, the Scottish obstetrician who discovered the anaesthetic effects of chloroform on humans,James Young Simpson, had experimented with carbon tetrachloride as an anaesthetic.[56] Simpson named the compound "Chlorocarbon" for its similarity to chloroform. His experiments involved injecting carbon tetrachloride into two women's vaginas. Simpson orally consumed carbon tetrachloride and described it as having "the same effect as swallowing a capsule of chloroform".[57]
Because of the higher amount of chlorine atoms (compared to chloroform) in its molecule, carbon tetrachloride has a stronger anaesthetic effect than chloroform and required a smaller amount.[52] Its anaesthetic action was likened toether, rather than the related chloroform.[56] It is less volatile than chloroform, therefore it was more difficult to apply and needed warm water to evaporate.[56] Its smell has been described as "fruity",[56] quince-like[58] and "more pleasant than chloroform",[52] and had a "pleasant taste".[56] Carbon tetrachloride for anaesthetic use was made by the chlorination ofcarbon disulfide. It was used on at least 50 patients, of which most were women in labour.[59] During anaesthesia, carbon tetrachloride has caused such violent muscular contractions and negative effects on the heart in some patients that it had to be replaced with chloroform or ether.[56][60] Such use was experimental and the anaesthetic use of carbon tetrachloride never gained popularity due to its potential toxicity.
The veterinary doctor Maurice Crowther Hall (1881–1938) discovered in 1921 that carbon tetrachloride was highly effective as ananthelmintic in eradicatinghookworm via ingestion. In one of the clinical trials of carbon tetrachloride, it was tested on criminals to determine its safety for use on humans.[61] Beginning in 1922, capsules of pure carbon tetrachloride were marketed byMerck under the nameNecatorina (variants includeNeo-necatorina andNecatorine). Necatorina was used as a medication against parasitic diseases in humans. This medication was most prevalently used inLatin American countries.[62][63] Its toxicity was not well understood at the time and toxic effects were attributed to impurities in the capsules rather than carbon tetrachloride itself.[64] Due to carbon tetrachloride's toxicity,tetrachloroethylene (which was also investigated by Hall in 1925) replaced its use as an anthelmintic by the 1940s.[65]
Carbon tetrachloride once was a popularsolvent in organic chemistry, but because of its adverse health effects, it is rarely used today.[27] It is sometimes useful as a solvent forinfrared spectroscopy, because it lacks significant absorption bands above 1600 cm−1. Because carbon tetrachloride does not have any hydrogen atoms, it is also used in protonNMR spectroscopy. In addition to being toxic, its dissolving power is low.[66] Its use in NMR spectroscopy has been largely superseded bydeuterated solvents (mainlydeuterochloroform). The use of carbon tetrachloride in the determination of oil has been replaced by various other solvents, such astetrachloroethylene.[27] Because it has no C–H bonds, it is a useful solvent forhalogenations either by the elementalhalogen or by a halogenation reagent such asN-bromosuccinimide (these conditions are known asWohl–Ziegler bromination).[citation needed]
Between 1902 and 1908, carbon tetrachloride-based fire extinguishers began to appear in the United States, years after Europe.[44]
In 1910, the Pyrene Manufacturing Company of Delaware filed a patent to use carbon tetrachloride to extinguish fires.[67] The liquid was vaporized by the heat of combustion and extinguished flames, an early form ofgaseous fire suppression. At the time it was believed the gas displaced oxygen in the area near the fire, but later research found that the gas inhibited the chemical chain reaction of the combustion process.[citation needed]
In 1911, Pyrene patented a small, portable extinguisher that used the chemical.[68] The extinguisher consisted of abrass bottle with an integrated hand-pump that was used to expel a jet of liquid toward the fire. As the container was unpressurized, it could easily be refilled after use.[69] Carbon tetrachloride was suitable for liquid and electrical fires and the extinguishers were often carried on aircraft or motor vehicles. However, as early as 1920, there were reports of fatalities caused by the chemical when used to fight a fire in a confined space.[23]
In the first half of the 20th century, another common fire extinguisher was a single-use, sealed glass globe, a "fire grenade, " filled with carbon tetrachloride or salt water. The bulb could be thrown at the base of the flames to quench the fire. The carbon tetrachloride type could also be installed in a spring-loaded wall fixture with asolder-based restraint. When the solder melted by high heat, the spring would either break the globe or launch it out of the bracket, allowing the extinguishing agent to be automatically dispersed into the fire.[70]
Since carbon tetrachloride freezes at –23 °C, the fire extinguishers would contain only 89–90% carbon tetrachloride and 10%trichloroethylene (m.p. –85 °C) orchloroform (m.p. –63 °C) for lowering the extinguishing mixture's freezing point down to temperatures as low as –45 °C. The extinguishers with 10% trichloroethylene would contain 1%carbon disulfide as a stabiliser.[44]
Prior to theMontreal Protocol, large quantities of carbon tetrachloride were used to produce thechlorofluorocarbon refrigerants R-11 (trichlorofluoromethane) and R-12 (dichlorodifluoromethane). However, these refrigerants play a role inozone depletion and have been phased out. Carbon tetrachloride is still used to manufacture less destructive refrigerants.[citation needed]
Carbon tetrachloride was widely used as afumigant to kill insect pests in stored grain.[71] It was employed in a mixture known as 80/20, that was 80% carbon tetrachloride and 20%carbon disulfide.[72] TheUnited States Environmental Protection Agency banned its use in 1985.[73]
Another carbon tetrachloride fumigant preparation mixture containedacrylonitrile. Carbon tetrachloride reduced the flammability of the mixture. Most common trade names for the preparation wereAcritet,Carbacryl andAcrylofume.[74] The most common preparation,Acritet, was prepared with 34 percent acrylonitrile and 66 percent carbon tetrachloride.[75][76]
{{cite book}}:ISBN / Date incompatibility (help)Robert Higginbotham, a blues and jazz singer who performed under the name Tommy Tucker, died Friday at College Hospital in Newark. Mr. Higginbotham, who lived in East Orange, N.J., was 48 years old. ... A native of Springfield, Ohio, he had lived in East Orange for 17 years. He was a licensed real-estate broker and had been an amateur prize fighter as a young man.
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