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Tetrachloroethylene
Tetrachloroethylene, also known as perchloroethylene or under the systematic name tetrachloroethene, and abbreviations such as perc (or PERC), and PCE, is a chlorocarbon with the formula . It is a non-flammable, stable, colorless and heavy liquid widely used for dry cleaning of fabrics and occasionally as a highly effective automotive brake cleaner. It has a mildly sweet, sharp odor, detectable by most people at a concentration of 50 ppm. Tetrachloroethylene is regarded as a toxic substance, a human health hazard, and an environmental hazard. In 2020, the United States Environmental Protection Agency stated that "tetrachloroethylene exposure may harm the nervous system, liver, kidneys, and reproductive system, and may be harmful to unborn children", and reported that numerous toxicology agencies regard it as a carcinogen. History and production French chemist Henri Victor Regnault first synthesized tetrachloroethylene in 1839 by thermal decomposition of hexachloroethane f ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Trichloroethylene
Trichloroethylene (TCE) is an organochloride with the formula C2HCl3, commonly used as an industrial metal-degreasing solvent. It is a clear, colourless, non-flammable, volatile liquid with a chloroform-like pleasant mild smell and sweet taste.Trichloroethylene (TCE) on ATSDR Its name is trichloroethene. Trichloroethylene has been sold under a variety of trade names. Industrial abbreviations include trichlor, Trike, Tricky and tri. Under the trade names Trimar and Trilene, it was used as a [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tetrafluoroethylene
Tetrafluoroethylene (TFE) is a fluorocarbon with the chemical formula . It is a colorless gas. Its structure is . It is used primarily in the industrial preparation of fluoropolymers. It is the simplest perfluorinated alkene. It was first reported as "dicarbon tetrafluoride" in 1890. Properties Tetrafluoroethylene is a synthetic colorless, odorless gas that is insoluble in water. Like all unsaturated fluorocarbons, it is susceptible to nucleophilic attack. It is unstable towards decomposition to carbon and carbon tetrafluoride () and prone to form explosive peroxides in contact with air. Industrial use Polymerization of tetrafluoroethylene produces polytetrafluoroethylene (PTFE) polymers such as Teflon and Fluon. PTFE is one of the two fluorocarbon resins composed wholly of fluorine and carbon. The other resin composed purely of carbon and fluorine is the copolymer of TFE with typically 6–9% hexafluoropropene (HFP), which is known as FEP (fluorinated ethylene propylene c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dry Cleaning
Dry cleaning is any cleaning process for clothing and textiles using a solvent other than water. Clothes are instead soaked in a water-free liquid solvent (usually non-polar, as opposed to water which is a Solvent#Solvent classifications, polar solvent). Perchloroethylene (known in the industry as "perc") is the most commonly used solvent, although alternative solvents such as hydrocarbons, and decamethylcyclopentasiloxane are also used. Most natural fibers can be washed in water but some synthetics (e.g., viscose) react poorly with water and should be dry cleaned if possible. If not, this could result in changes in texture, strength, and shape. Additionally, certain specialty fabrics, including silk and rayon, may also benefit from dry cleaning to prevent damage. History The ancient Greeks and Romans had some waterless methods to clean textiles, involving the use of powdered chemicals and absorbent clay (fuller's earth). By the 1700s, the French were using turpentine-based s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tetrabromoethylene
Tetrabromoethylene is an organobromine compound with the chemical formula . Its structure is . Under standard conditions, it exists in a form of colorless crystals. It is a brominated derivative of ethylene. Tetrabromoethylene is a potential fungicide and bactericide on fruits. It was used in mineral separation. It is an irritant.https://pubchem.ncbi.nlm.nih.gov/compound/Ethene_-1_1_2_2-tetrabromo It is prepared from acetylene and bromine in multiple steps. One method involves dehydrobromination of pentabromoethane, other method involves bromination of dibromoethylene in chloroform.Miller, S. A. (1965). Acetylene: Its Properties, Manufacture, and Uses. UK Academic Press. Reaction of mercuric acetylide and bromine also gives tetrabromoethylene. It can be produced by oxybrominating butane with free oxygen and bromine. Tetrabromoethylene gives tribromoacetyl bromide upon treatment with fuming nitric acid.Perekalin, V. V. (1964). Unsaturated Nitro Compounds. See also ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tetraiodoethylene
Tetraiodoethylene, TIE or diiodoform, is an Organoiodine chemistry, organoiodine compound with the chemical formula . Its structure is . It is an odourless yellow crystalline solid that is soluble in benzene and chloroform, and insoluble in water.Lide, D. R. (1995). CRC Handbook of Chemistry and Physics. (Special Student Edition): A Ready-Reference Book of Chemical and Physical Data. CRC-Press. Page 522 It has been used as an antiseptic and a component in pesticide and fungicide formulations. It is the periodinated analogue of ethylene. It is a decomposition product of carbon tetraiodide and diiodoacetylene.''Peculiar Decomposition of Diiodoacetylene'', Victor Meyel and Wilhelm Pemsel (1896) Tetraiodoethylene reacts with ethylamine to give ethylamine di-tetraiodoethylene, , and ethylamine tetraiodoethylene, . Tetraiodoethylene and iodine pentafluoride yield iodopentafluoroethane.Journal of the Chemical Society. (1948). page 2188 Tetraiodoethylene turns brown and emits a character ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Carbon Tetrachloride
Carbon tetrachloride, also known by many other names (such as carbon tet for short and tetrachloromethane, also IUPAC nomenclature of inorganic chemistry, recognised by the IUPAC), is a chemical compound with the chemical formula CCl4. It is a non-flammable, dense, colourless liquid with a "sweet" chloroform-like odour that can be detected at low levels. It was formerly widely used in fire extinguishers, as a precursor to refrigerants, an anthelmintic and a cleaning agent, but has since been phased out because of environmental and safety concerns. Exposure to high concentrations of carbon tetrachloride can affect the central nervous system and degenerate the liver and kidneys. Prolonged exposure can be fatal. Properties In the carbon tetrachloride molecule, four chlorine atoms are positioned symmetrically as corners in a tetrahedron, tetrahedral configuration joined to a central carbon atom by single covalent bonds. Because of this symmetric geometry, CCl4 is non-polar. methane, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
1,1,2,2-Tetrachloroethane
1,1,2,2-tetrachloroethane (TeCA), also known by the brand names Bonoform, Cellon and Westron, is an organic compound. It is colorless liquid and has a sweet odor. It is used as an industrial solvent and as a separation agent. TeCA is toxic and it can be inhaled, consumed or absorbed through the skin. After exposure, nausea, dizziness or even liver damage may occur. History 1,1,2,2-Tetrachloroethane and 1,1,1,2-Tetrachloroethane were discovered by Auguste Laurent in 1836. 1,1,2,2-tetrachloroethane was used in large amounts to produce other chemicals like trichloroethylene, tetrachloroethylene, and 1,2-dichloroethylene. Because of its possible carcinogen effects on humans, the production of 1,1,2,2-tetrachloroethane has decreased significantly and is no longer widely used as an end-product. It is however still generated as a byproduct and as an intermediate product during manufacturing, where low levels of the chemical have been detected in the air. Uses 1,1,2,2-Tetrachloroethan ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Brake Cleaner
Brake cleaner, often also called '' parts cleaner'', is a mostly colorless cleaning agent, mainly used for cleaning the brake disks, the engine compartment and underfloor of motor vehicles. An important feature is that the brake cleaner leaves no residue after the solvents evaporate.Explosionsschutz beim Umgang mit brennbaren Reinigern in der Kfz-Werkstatt (PDF; 762 kB).' Composition Chlorinated brake cleaners (often sold as non-flammable) use organochlorides like tetrachloroethylene and dichloromethane. Historically 1,1,1-Trichloroethane was used, sometimes together with Tetrachloroethylene. It was phased out because of its ozone-depleting nature. Non-chlorinated brake cleaners use hydrocarbons as a main component; it will either be a low-boiling aliphatic compound or higher-boiling hydrocarbon mixture. Aromatics like benzene, toluene or xylene may also be used. The hydrocarbons used are sometimes made by hydrogenation from naphtha. The lipophilic liquids dissolve fat-so ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hexachloroethane
Hexachloroethane (perchloroethane) is an organochlorine compound with the chemical formula . Its structure is . 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 iron(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 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 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chemist
A chemist (from Greek ''chēm(ía)'' alchemy; replacing ''chymist'' from Medieval Latin ''alchemist'') is a graduated scientist trained in the study of chemistry, or an officially enrolled student in the field. Chemists study the composition of matter and its properties. Chemists carefully describe the properties they study in terms of quantities, with detail on the level of molecules and their component atoms. Chemists carefully measure substance proportions, chemical reaction rates, and other chemical properties. In Commonwealth English, pharmacists are often called chemists. Chemists use their knowledge to learn the composition and properties of unfamiliar substances, as well as to reproduce and synthesize large quantities of useful naturally occurring substances and create new artificial substances and useful processes. Chemists may specialize in any number of Chemistry#Subdisciplines, subdisciplines of chemistry. Materials science, Materials scientists and metallurgists sha ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
