TRICHLOROETHYLENE
TRICHLOROETHYLENE
CAS number: 79-01-6
EC number: 201-167-4
Molecular formula: C2HCl3
Trichloroethylene (TCE) is a volatile, colorless liquid organic chemical.
Trichloroethylene (TCE) does not occur naturally and is created by chemical synthesis.
Trichloroethylene (TCE) is used primarily to make refrigerants and other hydrofluorocarbons and as a degreasing solvent for metal equipment.
Trichloroethylene (TCE) is also used in some household products, such as cleaning wipes, aerosol cleaning products, tool cleaners, paint removers, spray adhesives, and carpet cleaners and spot removers.
Commercial dry cleaners also use trichloroethylene as a spot remover.
Trichloroethylene is a halocarbon commonly used as an industrial solvent, not to be confused with the similar 1,1,1-trichloroethane, also known as chlorothene. It has been sold under a variety of trade names including Trimar and Trilene and used as a volatile anesthetic and as an inhaled obstetrical analgesic. Environmental exposure, particularly groundwater and drinking water contamination from industrial discharge, is a major concern for human health and has been the subject of numerous incidents and lawsuits.
The chemical compound trichloroethylene is a halocarbon commonly used as an industrial solvent.
Trichloroethylene (TCE) is a clear, colourless non-flammable liquid with a chloroform-like sweet smell.
Trichloroethylene (TCE) should not be confused with the similar 1,1,1-trichloroethane, which is commonly known as chlorothene.
Chemical properties
Trichloroethylene is nonflammable. Trichloroethylene (TCE) is slightly soluble in water, and soluble in most other organic solvents.
Trichloroethylene, a colourless, toxic, volatile liquid belonging to the family of organic halogen compounds, nonflammable under ordinary conditions and used as a solvent and in adhesives. Trichloroethylene has a subtle, sweet odour.
Trichloroethylene was first prepared in 1864; its commercial manufacture, begun in Europe in 1908, is based on the reaction of 1,1,2,2-tetrachloroethane with dilute caustic alkali. The compound is denser than water, in which it is practically insoluble.
Trichloroethylene is used in dry cleaning, in degreasing of metal objects, and in extraction processes, such as removal of caffeine from coffee or of fats and waxes from cotton and wool. Trichloroethylene (TCE) is also used in adhesives, such as cement for polystyrene plastics like those found in model-building kits. Industrially, an important use for trichloroethylene is in the manufacture of tetrachloroethylene: trichloroethylene is treated with chlorine to form pentachloroethane, which is converted to tetrachloroethylene by reaction with caustic alkali or by heating in the presence of a catalyst.
Inhalation of the vapours (glue-sniffing) induces euphoria; the practice can be addictive. Inhalation of more than 50 ppm (parts per million) trichloroethylene can produce acute effects on the body, including nausea and vomiting, eye and throat irritation, dizziness, headache, and liver, heart, or neurological damage. Trichloroethylene exposure has been linked to Parkinson disease.
What is Trichloroethylene?
Trichloroethylene is a chlorinated hydrocarbon with a molecular formula of C2HCl3. Trichloroethylene (TCE) is colourless liquid with a sweet smell that is widely used as a vapour degreaser for metal parts. Trichloroethylene (TCE) is a non-flammable liquid, having no measurable flashpoint or flammable limits in air. Trichloroethylene (TCE) is miscible with most organic solvents but only slightly miscible in water.
Trichloroethylene (or trichlor) is an excellent solvent used in a variety of degreasing and cold cleaning applications, as well as other special applications. Available for shipment in barges, tank trucks, tank cars and ships, the following grades of trichlor are offered:
The IUPAC name is trichloroethene.
Industrial abbreviations include TCE, trichlor, Trike, Tricky and tri.
Trichloroethylene (TCE) has been sold under a variety of trade names.
Under the trade names Trimar and Trilene, trichloroethylene was used as a volatile anesthetic and as an inhaled obstetrical analgesic in millions of patients.
Groundwater and drinking water contamination from industrial discharge including trichloroethylene is a major concern for human health and has precipitated numerous incidents and lawsuits.
Uses
Trichloroethylene is an effective solvent for a variety of organic materials.
When it was first widely produced in the 1920s, trichloroethylene’s major use was to extract vegetable oils from plant materials such as soy, coconut, and palm.
Other uses in the food industry included coffee decaffeination and the preparation of flavoring extracts from hops and spices.
Trichloroethylene (TCE) has also been used for removing residual water in the production of 100% ethanol.
From the 1930s through the 1970s, both in Europe and in North America, trichloroethylene was used as a volatile anesthetic almost invariably administered with nitrous oxide.
Marketed in the UK by ICI under the trade name Trilene it was coloured blue (with a dye called waxoline blue) to avoid confusion with the similar smelling chloroform.
Trichloroethylene (TCE) replaced earlier anesthetics chloroform and ether in the 1940s, but was itself replaced in the 1960s in developed countries with the introduction of halothane, which allowed much faster induction and recovery times and was considerably easier to administer.
Trilene was also used as a potent inhaled analgesic, mainly during childbirth.
Trichloroethylene (TCE) was used with halothane in the Tri-service field anaesthetic apparatus used by the UK armed forces under field conditions.
As of 2000, however, Trichloroethylene (TCE) was still in use as an anesthetic in Africa.
Trichloroethylene (TCE) has also been used as a dry cleaning solvent, although replaced in the 1950s by tetrachloroethylene (also known as perchloroethylene), except for spot cleaning where it was used until the year 2000.
Trichloroethylene was marketed as ‘Ecco 1500 Anti-Static Film Cleaner and Conditioner’ until 2009, for use in automatic movie film cleaning machines, and for manual cleaning with lint-free wipes.
Perhaps the greatest use of Trichloroethylene (TCE) has been as a degreaser for metal parts.
The demand for Trichloroethylene (TCE) as a degreaser began to decline in the 1950s in favor of the less toxic 1,1,1-trichloroethane.
However, 1,1,1-trichloroethane production has been phased out in most of the world under the terms of the Montreal Protocol, and as a result trichloroethylene has experienced some resurgence in use as a degreaser.
What is trichloroethylene?
Trichloroethylene is a colourless, highly volatile liquid with a sweet chloroform-like odour.
Other names for trichloroethylene include TCE, trichloroethene and ethylene trichloride.
What is trichloroethylene used for?
The main use of trichloroethylene is in metal cleaning and degreasing. Trichloroethylene (TCE) is also used as a chemical intermediate and an extraction solvent in the textile manufacturing industry.
In the past, trichloroethylene was used as a grain fumigant, an extraction solvent in the food industry, an anaesthetic agent and an analgesic. Trichloroethylene (TCE) was also used in the dry cleaning industry
until the mid-1950s, when it was replaced by tetrachloroethylene.
How does trichloroethylene get into the environment?
Trichloroethylene may be released into the environment from its use. The majority of trichloroethylene released enters the air. Trichloroethylene may also occur in ground water and surface water.
Trichloroethylene is primarily used as a solvent to remove greases from metal parts. As a solvent or as a component of solvent blends trichloroethylene is used with adhesives, lubricants, paints, varnishes, paint strippers, pesticides, and cold metal cleaners. Trichloroethylene (TCE) is used to make other chemicals (pharmaceuticals, polychlorinated aliphatics, flame retardants, and insecticides). Trichloroethylene (TCE) is used as an extraction solvent for greases, oils, fats, waxes and tars. The textile industry uses it to scour cotton, wool and other fabrics, and in waterless dying and finishing. Trichloroethylene (TCE) is used as a refrigerant for low temperature heat transfer.
Trichloroethylene (TCE) has also been used in the United States to clean kerosene-fueled rocket engines (Trichloroethylene (TCE) was not used to clean hydrogen-fueled engines such as the Space Shuttle Main Engine).
During static firing, the RP-1 fuel would leave hydrocarbon deposits and vapors in the engine.
These deposits had to be flushed from the engine to avoid the possibility of explosion during engine handling and future firing.
Trichloroethylene (TCE) was used to flush the engine’s fuel system immediately before and after each test firing.
The flushing procedure involved pumping Trichloroethylene (TCE) through the engine’s fuel system and letting the solvent overflow for a period ranging from several seconds to 30–35 minutes, depending upon the engine.
For some engines, the engine’s gas generator and liquid oxygen (LOX) dome were also flushed with Trichloroethylene (TCE) prior to test firing.
The F-1 rocket engine had its LOX dome, gas generator, and thrust chamber fuel jacket flushed with Trichloroethylene (TCE) during launch preparations.
Trichloroethylene (TCE) is also used in the manufacture of a range of fluorocarbon refrigerants[13] such as 1,1,1,2-tetrafluoroethane more commonly known as HFC 134a.
Trichloroethylene (TCE) was also used in industrial refrigeration applications due to its high heat transfer capabilities and its low temperature specification.
Many industrial refrigeration applications used Trichloroethylene (TCE) up to the 1990s in applications such as car testing facilities.
Chemical instability
Despite its widespread use as a metal degreaser, trichloroethylene itself is unstable in the presence of metal over prolonged exposure.
As early as 1961 this phenomenon was recognized by the manufacturing industry, when stabilizing additives were added to the commercial formulation.
Since the reactive instability is accentuated by higher temperatures, the search for stabilizing additives was conducted by heating trichloroethylene to its boiling point in a reflux condenser and observing decomposition.
Definitive documentation of 1,4-dioxane as a stabilizing agent for Trichloroethylene (TCE) is scant due to the lack of specificity in early patent literature describing Trichloroethylene (TCE) formulations.
Other chemical stabilizers include ketones such as methyl ethyl ketone.
Trichloroethylene is a synthetic, light sensitive, volatile, colorless, liquid that is miscible with many non-polar organic solvents. Trichloroethylene is used mainly as a degreaser for metal parts. Upon combustion, it produces irritants and toxic gases. Occupational exposure to trichloroethylene is associated with excess incidences of liver cancer, kidney cancer and non-Hodgkin lymphoma. Trichloroethylene (TCE) is reasonably anticipated to be a human carcinogen.
Trichloroethylene appears as a clear colorless volatile liquid having a chloroform-like odor. Denser than water and is slightly soluble in water. Noncombustible. Used as a solvent, fumigant, in the manufacture of other chemicals, and for many other uses.
Trichloroethylene (TCE) is a nonflammable, colorless liquid with a somewhat sweet odor and a sweet, burning taste. Trichloroethylene (TCE) is used mainly as a solvent to remove grease from metal parts, but it is also an ingredient in adhesives, paint removers, typewriter correction fluids, and spot removers.Trichloroethylene is not thought to occur naturally in the environment. However, it has been found in underground water sources and many surface waters as a result of the manufacture, use, and disposal of the chemical.
Use and Manufacturing
Household Products
-Auto Products
-Commercial / Institutional
-Hobby/Craft
-Home Maintenance
-Home Office
-Inside the Home
The main use of trichloroethylene is in the vapor degreasing of metal parts. Trichloroethylene is used in consumer products such as typewriter correction fluids, paint removers/strippers, adhesives, spot removers, and rug-cleaning fluids.
Trichloroethylene is used as chemical intermediate for the production of hydrofluorocarbons (e.g., HFC134a, HFC125), monochloroacetic acid, blowing agents, flame retardants, and some agricultural chemicals. The other major use is as solvent for vapor degreasing in the metal industry. … Trichloroethylene is further used in solvent formulations for rubbers, adhesives, industrial paints, and in the manufacture of lithium-ion batteries. In the production of poly(vinyl chloride), it serves as a chain-transfer agent to control the molecular mass distribution.
Metal degreasing; extraction solvent for oils, fats, waxes; solvent dyeing; dry-cleaning; refrigerant and heat-exchange liquid; fumigant; cleaning and drying electronic parts; diluent in paints and adhesives; textile processing; chemical intermediate; aerospace operations (flushing liquid oxygen).
Industry Uses
-Adhesives and sealant chemicals
-Corrosion inhibitors and anti-scaling agents
-Functional fluids (closed systems)
-Intermediates
-Metal foams
-Solvents (for cleaning and degreasing)
-Solvents (which become part of product formulation or mixture)
Consumer Uses
-Adhesives and sealants
-Building/construction materials not covered elsewhere
-Cleaning and furnishing care products
-Facility Solvent Usage
-Industrial vapor degreasing solvent.
-Lubricants and greases
-Metal products not covered elsewhere
-Paints and coatings
Methods of Manufacturing
The production of trichloroethylene is mainly based on acetylene or ethylene. The acetylene route comprises acetylene chlorination to 1,1,2,2-tetrachloroethane followed by dehydrochlorination to trichloroethylene. In the ethylene-based processes, ethylene or ethylene-based chlorohydrocarbons, preferably 1,2-dichloroethane, are chlorinated or oxychlorinated and dehydrochlorinated in the same reactor. Tetrachloroethylene is obtained as a byproduct in substantial amounts. Some production is based on the catalytic hydrogenation of tetrachloroethylene coming from the chlorinolysis of C1 to C3 chlorohydrocarbons.
Until 1968, about 85% of United States production capacity of trichloroethylene was based on acetylene. The acetylene-based process consists of two steps: acetylene is first chlorinated to 1,1,2,2-tetrachloroethane, with a ferric chloride, phosphorus chloride or antimony chloride catalyst, and the product is then dehydrohalogenated to trichloroethylene. The current method of manufacture is from ethylene or 1,2-dichloroethane. In a process used by one plant in the United States, trichloroethylene is produced by noncatalytic chlorination of ethylene dichloride and other C2 hydrocarbons with a mixture of oxygen and chlorine or hydrogen chloride.
Prepn from sym-tetrachlorethane by elimination of /hydrochloric acid/ (by boiling with lime) … ; by passing tetrachloroethane vapor over /calcium chloride/ catalyst at 300 °C … ; without catalyst at 450-470 °C … .
General Manufacturing Information
Industry Processing Sectors
-Adhesive manufacturing
-All other basic inorganic chemical manufacturing
-All other basic organic chemical manufacturing
-All other chemical product and preparation manufacturing
-Computer and electronic product manufacturing
-Construction
-Fabricated metal product manufacturing
-Government (Department of Transportation)
-Industrial gas manufacturing
-Machinery manufacturing
-Miscellaneous manufacturing
-Paint and coating manufacturing
-Paper manufacturing
-Petroleum lubricating oil and grease manufacturing
-Plastics product manufacturing
-Primary metal manufacturing
-Services
-Soap, cleaning compound, and toilet preparation manufacturing
-Transportation equipment manufacturing
-Wholesale and retail trade
IDENTIFICATION AND USE:
Trichloroethylene (TCE) is a colorless liquid (unless dyed blue). The major use of Trichloroethylene (TCE) is in metal cleaning or degreasing. Trichloroethylene (TCE) was used earlier as an extraction solvent for natural fats and oils, such as palm, coconut and soya bean oils. Trichloroethylene (TCE) was also an extraction solvent for spices, hops and the decaffeination of coffee. The United States Food and Drug Administration banned these uses of trichloroethylene. Its use in cosmetic and drug products was also discontinued. Trichloroethylene (TCE) was also used as both an anesthetic and an analgesic in obstetrics.
About Trichloroethylene (TCE)
Helpful information
Trichloroethylene (TCE) is registered under the REACH Regulation and is manufactured in and / or imported to the European Economic Area, at ≥ 10 000 tonnes per annum.
Trichloroethylene (TCE) is used by professional workers (widespread uses), in formulation or re-packing, at industrial sites and in manufacturing.
Consumer Uses
ECHA has no public registered data indicating whether or in which chemical products the substance might be used. ECHA has no public registered data on the routes by which Trichloroethylene (TCE) is most likely to be released to the environment.
Article service life
ECHA has no public registered data on the routes by which Trichloroethylene (TCE) is most likely to be released to the environment. ECHA has no public registered data indicating whether or into which articles the substance might have been processed.
Widespread uses by professional workers
ECHA has no public registered data indicating whether or in which chemical products the substance might be used. ECHA has no public registered data on the types of manufacture using Trichloroethylene (TCE). Release to the environment of Trichloroethylene (TCE) can occur from industrial use: in processing aids at industrial sites and as an intermediate step in further manufacturing of another substance (use of intermediates).
Other release to the environment of Trichloroethylene (TCE) is likely to occur from: indoor use in close systems with minimal release (e.g. cooling liquids in refrigerators, oil-based electric heaters) and outdoor use in close systems with minimal release (e.g. hydraulic liquids in automotive suspension, lubricants in motor oil and break fluids).
Formulation or re-packing
ECHA has no public registered data indicating whether or in which chemical products the substance might be used. Release to the environment of Trichloroethylene (TCE) can occur from industrial use: formulation of mixtures.
Uses at industrial sites
Trichloroethylene (TCE) has an industrial use resulting in manufacture of another substance (use of intermediates).
Trichloroethylene (TCE) is used in the following areas: formulation of mixtures and/or re-packaging.
Trichloroethylene (TCE) is used for the manufacture of: chemicals.
Release to the environment of Trichloroethylene (TCE) can occur from industrial use: in processing aids at industrial sites, as an intermediate step in further manufacturing of another substance (use of intermediates), of substances in closed systems with minimal release and manufacturing of the substance.
Manufacture
Release to the environment of Trichloroethylene (TCE) can occur from industrial use: manufacturing of the substance and as an intermediate step in further manufacturing of another substance (use of intermediates).
Trichloroethylene (IUPAC), CHClCCl2, is a stable, low-boiling, colorless liquid with a chloroform-like odor. Trichloroethylene (TCE) is not corrosive to the common metals even in the presence of moisture. Trichloroethylene (TCE) is slightly soluble in water and is nonflammable. Trichloroethylene (TCE) is toxic by inhalation, with a TLV of 50 ppm and an IDLH of 1000 ppm in air. The FDA has prohibited its use in foods, drugs, and cosmetics. The four-digit UN identification number is 1710. The NFPA 704 designation is health 2, flammability 1, and reactivity 0. Its primary uses are in metal degreasing, dry cleaning, as a refrigerant and fumigant, and for drying electronic parts.
Trichloroethylene (TCE) is a clear, colorless, nonflammable (at room temperature) stable toxic liquid with chloroform-like odor (ATSDR, 2011). Trichloroethylene (TCE) is slightly soluble in water, is soluble in greases and common organic solvents, and boils at 87°C (190 F).
On contact with air, it slowly decomposes and forms phosgene, hydrogen chloride, and dichloroacetyl chloride. Trichloroethylene in contact with water becomes corrosive and forms dichloroacetic acid and hydrochloric acid. Trichloroethylene (TCE) is soluble in methanol, diethyl ether, and acetone.
Trichloroethylene is also known as trichloroethene, acetylene trichloride, 1-chloro-2,2- dichloroethylene, and ethylene trichloride, and it is also commonly abbreviated to TRI. Trichloroethylene (TCE) is a volatile, chlorinated organic hydrocarbon that is widely used for degreasing metals and as a hydrofluorocarbon (HFC-134a) intermediate (ATSDR, 2013). Trichloroethylene (TCE) is also used in adhesives, paint-stripping formulations, paints, lacquers, and varnishes. In the 1930s, Trichloroethylene (TCE) was introduced for use in dry cleaning, but this practice was largely discontinued in the 1950s when Trichloroethylene (TCE) was replaced by tetrachloroethylene (PCE). Trichloroethylene (TCE) has a number of other past uses in cosmetics, drugs, foods, and pesticides (US EPA, 2011). Trichloroethylene (TCE) is an environmental contaminant that has been detected in air, groundwater, surface waters, and soil (US EPA, 2011; NRC, 2006).
Physical properties
Clear, colorless, watery-liquid with a chloroform-like odor. Odor threshold concentrations determined in air were 21.4 ppmv (Leonardos et al., 1969) and 3.9 ppmv (Nagata and Takeuchi, 1990). The average least detectable odor threshold concentrations in water at 60 °C and in air at 40 °C were 10 and 2.6 mg/L, respectively (Alexander et al., 1982).
Uses
Trichloroethylene is used as a solvent, in drycleaning, in degreasing, and in limited use asa surgical anesthetic.
A chlorinated hydrocarbon used as a detergent or solvent for metals, oils, resins, sulfur and as gemal degreasing agent. Trichloroethylene (TCE) can cause irritant contact dermatitis, generalized exanthema, Stevens-Johnson syndrome, pustular or bullous eruption and scleroderma.
Solvent for fats, waxes, resins, oils, rubber, paints, and varnishes. Solvent for cellulose esters and ethers. Used for solvent extraction in many industries. In degreasing, in dry cleaning. In the manufacture of organic chemicals, pharmaceuticals, such as chloroacetic acid.
Production Methods
Trichloroethylene (TCE) has been in commercial use for almost 60 years. Trichloroethylene (TCE) has been used as a solvent because of its powerful ability to dissolve fats, greases, and waxes. Trichloroethylene (TCE) has been widely used in the dry cleaning industry and as a metal degreaser and in the electronic components industry where workers have been observed using it as a cleaning solvent without any protective equipment, thus allowing uncontrolled skin contact and inhalation exposures.
High-purity grades of trichloroethylene are used as a feedstock in the synthesis of the refrigerant hydrofluorocarbon 134a. In this process, the trichloroethylene molecule is destroyed to form the new fluorinated compound.
Trichloroethylene’s advantages for metal cleaning include the ability to degrease more thoroughly and several times faster than alkaline cleaners, and its compatibility with smaller equipment that consumes less energy. Trichloroethylene is an important solvent for degreasing aluminum and for cleaning sheet and strip steel prior to galvanizing. Trichloroethylene also is used for cleaning liquid oxygen and hydrogen tanks. Commercial trichloroethylene formulations include a stabilizer system to help prevent solvent breakdown caused by contaminants, such as acids, metal chips, and fines, and exposure to oxygen, light, and heat.
Trichloroethylene is also used as a solvent in some nonflammable adhesive and aerosol formulations, and as a low temperature heat-transfer medium. Other applications of trichloroethylene include its use as a solvent in the metal processing, electronics, printing, pulp and paper, and textile industries.
Trichloroethylene (TCE) is used as a solvent for degreasing metal parts during the manufacture of a variety of products. Trichloroethylene (TCE) can be found in consumer products, including some wood finishes, adhesives, paint removers, and stain removers. Trichloroethylene (TCE) can also be used in the manufacture of other chemicals.
Trichloroethylene (TCE) is:
-is a nonflammable, colorless liquid at room temperature.
-evaporates easily into air.
-has an ether-like odor at high concentrations; at lower levels, there is no odor to warn people that contaminants are in the air.
Trichloroethylene (TCE) that has been spilled or dumped on the ground can pollute soil and groundwater.
Because Trichloroethylene (TCE) moves from water to air easily, it is not usually found in surface soils or in open surface water.
Trichloroethylene (TCE) spilled on the ground can move down through the soil and into water under the ground where it may pollute private and public drinking water wells. Trichloroethylene (TCE) can also move from water under the ground into rivers or lakes and then quickly move into the air.
Trichloroethylene (TCE) can evaporate from the polluted soil and groundwater and rise toward the ground surface.
If these Trichloroethylene (TCE) vapors come to a basement as they travel to the surface, they may enter through cracks in the foundation, around pipes, or through a sump or drain system. In this way, the vapors enter buildings and contaminate indoor air. This process, when pollution moves from air spaces in soil to indoor air, is called vapor intrusion.
Tricholoroethylene (TCE) is a volatile organic compound mostly used to manufacture refrigerant chemicals in a closed system. Trichloroethylene (TCE) is also used as a solvent for degreasing, as a spot cleaner in dry cleaning, and in consumer products (cleaners and solvent degreasers, adhesives, lubricants, hoof polishes, mirror edge sealants, and pepper spray).
PRODUCTION
Nine entities manufactured or imported almost 225 million pounds of TCE in the U.S. in 2011, according to Chemical Data Reporting by the chemical industry to EPA. The manufacturers who disclosed their names were Dow Chemical and Solvchem Inc. in Texas and PPG Industries and Shin Etsu in Louisiana. Two entities claimed their names as confidential business information.
Trichloroethylene (CICH=CCl2) is a colorless liquid with a chloroform-like odor. Trichloroethylene may cause irritation to the eyes and skin. Exposure to high concentrations can cause dizziness, headaches, sleepiness, confusion, nausea, unconsciousness, liver damage, and even death. Trichloroethylene is a known carcingen. Workers may be harmed from exposure to trichloroethylene. The level of exposure depends upon the dose, duration, and work being done.
Trichloroethylene is used in many industries. Trichloroethylene (TCE) is mostly used as a solvent to remove grease from metal parts, but it is also an ingredient in adhesives, paint removers, typewriter correction fluids, and spot removers. Some examples of workers at risk of being exposed to trichloroethylene include the following:
Workers who use this substance for metal degreasing
Workers who use it as an extraction solvent for greases, oils, fats, waxes, and tars
Factory workers in the textile processing industry who use it to scour cotton, wool, and other fabrics
Dry cleaning workers who use it to remove spots
Factory workers in plants that manufacture pharmaceuticals
Chemical workers who use it to make other chemicals
Uses
The main use of trichloroethylene is in the vapor degreasing of metal parts.
Trichloroethylene is also used as an extraction solvent for greases, oils, fats, waxes, and tars, a chemical
intermediate in the production of other chemicals, and as a refrigerant.
Trichloroethylene is used in consumer products such as typewriter correction fluids, paint
removers/strippers, adhesives, spot removers, and rug-cleaning fluids.
Trichloroethylene was used in the past as a general anesthetic.
Trichloroethylene (TCE) is a chlorine containing organic compound, widely employed as an industrial solvent.
TCE is formed as a major intermediate during the biodegradation of tetrachloroethylene (PCE) in a small anaerobic continuous-flow fixed film column.
Application
Trichloroethylene may be employed for various industrial processes, such as metal cleaning and degreasing. Trichloroethylene (TCE) may be used to synthesize chloroacetic acid.
Key Points
– trichloroethylene is a colourless, highly volatile liquid with a sweet odour
– it is mainly used in metal cleaning and degreasing
– in the past it has been used as a grain fumigant, an anaesthetic and in the dry cleaning industry
– breathing in trichloroethylene can cause excitement, dizziness, headache, nausea and vomiting followed by drowsiness and coma
– more severe exposures may cause heart problems and in some cases death
– drinking trichloroethylene can cause burning of the mouth and throat, nausea, vomiting and diarrhoea
– the International Agency for Research on Cancer (IARC) has classified trichloroethylene as having the ability to cause cancer in humans
Physical properties
Trichloroethylene is a colourless, liquid with a sweet odour, and a sweet burning taste.
Melting Point: -73°C
Boiling Point: 86.7°C
Vapour Density: 4.53
Specific Gravity: 1.456
Flashpoint: 89.6°C
Degreasing and general solvent grade for heavy-duty vapor degreasing and cold cleaning
Dual-purpose grade may be used for liquid oxygen flushing and vapor degreasing
High-purity grade is a low residue solvent for cleaning electronic components, chemical synthesis and liquid oxygen flushing
Fluorocarbon grade for feedstock applications
History
Pioneered by Imperial Chemical Industries in Britain, its development was hailed as an anesthetic revolution.
Originally thought to possess less hepatotoxicity than chloroform, and without the unpleasant pungency and flammability of ether, Trichloroethylene (TCE) use was nonetheless soon found to have several pitfalls.
These included promotion of cardiac arrhythmias, low volatility and high solubility preventing quick anesthetic induction, reactions with soda lime used in carbon dioxide absorbing systems, prolonged neurologic dysfunction when used with soda lime, and evidence of hepatotoxicity as had been found with chloroform.
The introduction of halothane in 1956 greatly diminished the use of Trichloroethylene (TCE) as a general anesthetic.
Trichloroethylene (TCE) was still used as an inhalation analgesic in childbirth given by self-administration.
Fetal toxicity and concerns for carcinogenic potential of Trichloroethylene (TCE) led to its abandonment in developed countries by the 1980s.
The use of trichloroethylene in the food and pharmaceutical industries has been banned in much of the world since the 1970s due to concerns about its toxicity.
Legislation has forced the replacement of trichloroethylene in many processes in Europe as the chemical was classified as a carcinogen carrying an R45 risk phrase, May cause cancer.
Many degreasing chemical alternatives are being promoted such as Ensolv and Leksol; however, each of these is based on n-propyl bromide which carries an R60 risk phrase of May impair fertility, and they would not be a legally acceptable substitute.
Groundwater contamination by Trichloroethylene (TCE) has become an important environmental concern for human exposure.
In 2005 it was announced by the United States Environmental Protection Agency that the agency had completed its Final Health Assessment for Trichloroethylene and released a list of new Trichloroethylene (TCE) toxicity values.
The results of the study have formally characterized the chemical as a human carcinogen and a non-carcinogenic health hazard.
A 2011 toxicological review performed by the EPA continues to list trichloroethylene as a known carcinogen.
Production
Prior to the early 1970s, most trichloroethylene was produced in a two-step process from acetylene.
First, acetylene was treated with chlorine using a ferric chloride catalyst at 90 °C to produce 1,1,2,2-tetrachloroethane according to the chemical equation
HC≡CH + 2 Cl2 → Cl2CHCHCl2
The 1,1,2,2-tetrachloroethane is then dehydrochlorinated to give trichloroethylene.
This can be accomplished either with an aqueous solution of calcium hydroxide
2 Cl2CHCHCl2 + Ca(OH)2 → 2 ClCH=CCl2 + CaCl2 + 2 H2O
or in the vapor phase by heating it to 300–500 °C on a barium chloride or calcium chloride catalyst
Cl2CHCHCl2 → ClCH=CCl2 + HCl
Today, however, most trichloroethylene is produced from ethylene.
First, ethylene is chlorinated over a ferric chloride catalyst to produce 1,2-dichloroethane.
CH2=CH2 + Cl2 → ClCH2CH2Cl
When heated to around 400 °C with additional chlorine, 1,2-dichloroethane is converted to trichloroethylene
ClCH2CH2Cl + 2 Cl2 → ClCH=CCl2 + 3 HCl
This reaction can be catalyzed by a variety of substances.
The most commonly used catalyst is a mixture of potassium chloride and aluminum chloride.
However, various forms of porous carbon can also be used.
This reaction produces tetrachloroethylene as a byproduct, and depending on the amount of chlorine fed to the reaction, tetrachloroethylene can even be the major product.
Typically, trichloroethylene and tetrachloroethylene are collected together and then separated by distillation.
IUPAC NAMES
1,1,2-Trichloroethene
1,1,2-trichloroethene
1,1,2-tricloroetene
tri
trichlorethene
trichlorethylen
Trichloroethene
trichloroethene
trichloroethilene
Trichloroethylene
trichloroethylene
Trichloroethylene
trichloroethylene
trichloréthylène
Tricloroeteno
TRICHLOROETHYLENE
Trichloroethene
79-01-
1,1,2-Trichloroethene
Ethene, trichloro-
Ethylene trichloride
Ethinyl trichloride
Acetylene trichloride
Narcogen
Trilene
Trichlorethylene
1,1,2-Trichloroethylene
Chlorilen
Trethylene
Trielina
triciene
Blancosolv
Crawhaspol
Densinfluat
Germalgene
Threthylen
Threthylene
Trichloraethen
Trichloran
Trichloren
AlgylenAnamenth
Benzinol
Blacosolv
Cecolene
Chlorylen
Circosolv
Dukeron
Lanadin
Lethurin
Narkosoid
Petzinol
Triasol
Trielene
Trielin
Trieline
Vestrol
Westrosol
Fluate
Nialk
Philex
Trial
Trilen
Trimar
Vitran
Fleck-flip
Flock flip
Tri-plus
Triklone N
Dow-tri
Tri-Clene
Perm-A-chlor
1,1-Dichloro-2-chloroethylene
1-Chloro-2,2-dichloroethylene
Tri-plus M
Trichlooretheen
Tricloretene
Tricloroetilene
Trichlorethylenum
trichloroethylenum
Trichloraethylenu
TCE
Ethene, 1,1,2-trichloro-
1,2,2-Trichloroethylene
Tricloroetileno
Chlorylea
Chorylen
Ethylene, trichloro-
Gemalgene
Narkogen
Trichloraethylen, tri
Trichlorethylene, tri
Triclene
Triklone
Triline
Trichloorethyleen, tri
Trilene TE-141
Tricloroetilene [DCIT]
Trichloroethylene (TCE) (chlorohydrocarbon)
C2HCl3
Perm-A-clor
Rcra waste number U228
Trichloroethylene (IUPAC)
trichlor
Trichlorethene
Trichloraethylen
NCI-C04546
Distillex DS2
R 1120
UNII-290YE8AR51
UN 1710
TRI
trichloraethylenum pro narcosi
Trichloroethylene (without epichlorohydrin)
CHEBI:16602
290YE8AR51
MFCD00000838
NCGC00091202-0
DSSTox_CID_1382
DSSTox_RID_76125
DSSTox_GSID_21383
Trielina [Italian]
Caswell No. 876
Trichlorathane
Tricloretene [Italian]
densi nfluat
Trichlooretheen [Dutch]
Trichloraethen [German]
Trichloroethylene (TCE)
Trichloroethylene [INN]
trik lone
tric hloroethene
Tricloroetilene [Italian]
trichloro ethylene
CAS-79-01-6
CCRIS 603
Trichloroethene 100 microg/mL in Methanol
Trichloride, EthinylTrichloroethene 1000 microg/mL in Methanol
Trichloroethylene, ACS reagent, >=99.5%
Tricloroetileno [INN-Spanish]
HSDB 133
Trichloorethyleen, tri [Dutch]
Trichloraethylen, tri [German]
Trichlorethylene, tri [French]
Trichloroethylenum [INN-Latin]
NSC 389
Trichloroethylene, 99+%, extra pure, stabilized
Trichloroethylene, 99.6%, ACS reagent, stabilized
EINECS 201-167-4
UN1710
RCRA waste no. U228
EPA Pesticide Chemical Code 081202
BRN 1736782
Trichloroethylene [INN:NF]
Trichlorothene
trichloro-ethene
AI3-00052
Disparit B
trichloro-ethyleneAltene DG
F 1120
Trichloroethene, 9CI
Trichloroethylene [UN1710] [Poison]
Trichloroethylene (with epichlorohydrin)
1,1,1-Trichloroethylene
ACMC-1BMG7
1,1,2-Trichloro-Ethene
EC 201-167-4
Trichloroethylene, anhydrous
SCHEMBL5754
Trichloroethylene, >=99%
Trichloroethylene, stabilized
4-01-00-00712 (Beilstein Handbook Reference)
Chlorylea, Chorylen, CirCosolv, Crawhaspol, Dow-Tri, Dukeron, Per-A-Clor, Triad, Trial, TRI-Plus M,Vitran
1,1,2-tris(chloranyl)ethene
Trichloroethylene, p.a., 98%
Trichloroethylene, LR, >=99%
Trichloroethylene, Electronic Grade
Trichloroethylene Reagent Grade ACS
Trichloroethylene, analytical standard
Trichloroethylene, Semiconductor Grade
Trichloroethylene [UN1710] [Poison]
Trichloroethene 10 microg/mL in Methanol
Trichloroethylene, Spectrophotometric Grade
Trichloroethylene, SAJ first grade, >=98.0%
Trichloroethylene, puriss. p.a., >=99.5% (GC)
BRD-K46435528-001-01-0
Trichloroethylene, spectrophotometric grade, >=99.5%