Dry Cleaning of Clothes

Perchloroethylene (PERC), Cl2C=CCl2 is commonly being used as a solvent for dry cleaning. It is now known that PERC contaminates ground water and is a suspected human carcinogen. 

A technology, known as Micell Technology developed by Joseph De Simons, Timothy Romack, and James McClain made use of liquid carbon dioxide and a surfactant for dry cleaning clothes, thereby replacing PERC. Dry cleaning machines have now been developed using this technique. 

Micell technology has also evolved a metal-cleaning system that uses carbon dioxide and a surfactant, thereby eliminating the need of halogenated solvents.  

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Halogenated alkanes are very useful as solvents in a variety of industrial processes (at one time they were the solvents of choice for the dry cleaning of clothes, for example). The scale of their use is such that their accidental or deliberate discharge into the environment can lead to long-term contamination problems. As is true for many environmental contaminants, the molecule originally released may not be a particular danger from an environmental perspeedve, but some product into which it is transformed may be considerably more cause for concern. 

Use of reverse micelles in synthetic chemistry to improve the rate and the yield of reactions seems likely to be a fruitful area of research in the future. In addition to catalysis, several other applications of reverse micelles can be cited. Just as nonpolar dirt is solubilized in aqueous micelles, so, too, polar dirt that would be unaffected by nonpolar solvents may be solubilized into reverse micelles. This plays an important role in the dry cleaning of clothing. Motor oils are also formulated to contain reverse micelles to solubilize oxidation products in the oil that might be corrosive to engine parts. 

Dry Cleaning. Condensed phase carbon dioxide is also used as a solvent for the dry cleaning of clothes. Although carbon dioxide alone is not a good solvent for oils, waxes, and greases, the use of carbon dioxide in combination with a surfactant allows for the replacement of perchloroethylene (which is the solvent used most often to dry clean clothes, although it poses hazards to the environment and is a suspected human carcinogen). 

Trichloroethane is the most common solvent used in the dry cleaning of clothes. Carbon tetrachloride (CCI4) was used in the past, but it has been found to cause liver damage and is carcinogenic. 

Tetrachloroethylene and trichloroethylene are used for the cleaning of metals finely purified and for dry cleaning of clothes as the cleaning solvents. As they are very poisonous we have to take care not to pollute the environment with these compounds. When we accidentally litter the environment with these compounds, the cleaning methods which remove them effectively using bacteria may be helpful. 

Miscellaneous Patents. The commonality in this section is the diversity of the patents. For example, grouped together are patents describing a coal slurry combustion process, the dry cleaning of clothes with carbon dioxide, the separation of inorganic salts from water, and the growth of crystals from supercritical solution. 

One area that is rich for development is the use of SCCO2 as a cleaning solvent. It has already been introduced for the dry-cleaning of clothes, and this application should become more widespread in future years. Supercritical CO2 is also used to clean optical and electronics components, as well as heavy-duty valves, tanks and pipes. 

Food contamination can occur in various ways. In the vicinity of factories for dry cleaning of clothing and textiles high concentrations of trichlorethylene (together with trichloromethane) in butter and lard (up to 0.76 mg/kg) were found. Other solvents found in foods include chloroethylene (vinyl chloride), which is used to make polyvinyl chloride (PVC), 1,1-dichloroethylene (vinyhdene chloride), used to produce copolymers with vinyl chloride (see Section 12.9.1.5), and (Z)- and ( )-l,2-dichloroethylene, which are used for various syntheses and as solvents. 

The polarity of the carbon-halogen bond makes haloalkanes useful for applications such as dry cleaning of clothing and degreasing of mechanical and electronic components. Alternatives... 

Uses In detergents for wann washing and dry cleaning of clothes emulsifier for textiles, agrochemicals... 

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