Halogenated hydrocarbons hexachloroethane

Humans can be exposed to hexachloroethane by inhalation, ingestion, or skin contact. There are no specific treatments for hexachloroethane overexposure. However, treatments available for halogenated hydrocarbons may be useful. 

In veterinary practice many of the halogenated hydrocarbons such as carbon tetrachloride, hexachloroethane (CI3C-CCI3), isomeric difluorotetrachloroethanes (C2F2CI4), namely 1,2-difluorotetrachloroethane (FCI2C-CFCI2/ Freon 112) or 1,1-di-... 

Synonyms Carbon hexachloride Carbon trichloride Ethane hexachloride Ethylene hexachloride 1,1,1,2,2,2-Hexachloroethane Hexachloroethylene Perchloroethane Classification Nonaromatic halogenated hydrocarbon Empirical C2CI6 Formula CCI3CCI3... 

The reaction mechanism described in Scheme 17.2 depends on the atomic H/Cl ratio of the tested molecules. Thus, totally chlorinated hydrocarbons such as carbon tetrachloride or hexachloroethane are essentially destroyed by hydrolysis in the presence of water, and the underchlorinated hydrocarbons undergo competitive hydrolysis and oxidation reactions [52]. Following the same mechanism, less halogenated hydrocarbons may also lead to alkenes (Scheme 17.3). 

Some preliminary examples of hydrolysis reactions illustrate the very wide range of reactivity of organic compounds. For example, triesters of phosphoric acid hydrolyze in nearneutral solution at ambient temperatures with half-lives ranging from several days to several years (Wolfe, 1980), whereas the halogenated alkanes pentachloroethane, carbon tetrachloride, and hexachloroethane have "environmental" (pH = 7 25°C) half-lives of about 2 hr, 50 yr, and 1000 millennia, respectively (Mabey and Mill, 1978 Jeffers et al., 1989). On the other hand, pure hydrocarbons from methane through the PAHs are not hydrolyzed under any circumstances that are environmentally relevant. 

In the field of halogenation, the practical aspects of the work were stressed by a number of Russian workers. Thus, in 1940 and later Mamedaliev reported (215) on the chlorination of methane over cupric chloride, pumice, iron, or aluminum shavings. Yields of 75 to 80% of products ranging from methyl chloride to carbon tetrachloride with small amounts of hexachloroethane were obtained. Similar work on the continuous chlorination of hydrocarbons such as isopentane, unsaturated compounds, oxygenated compounds, and on the mechanism of chlorination has been reported by Russian researchers from time to time (180,248,366,367,389). 

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