1.1.2- Trichloro-ethene tetrachloroethene

After growth in a medium containing suitable reductants such as glucose, a strain of Enterobacter agglomerans was able to reduce tetrachloroethene successively to trichloro-ethene and cis-, 2- dichloroethene (Sharma and McCarty 1996). 

Unlike petroleum hydrocarbons, organic compounds in general followed a different evolutionary path. Chlorinated solvents are a common group of organic compounds, and are also the most frequently encountered contaminant in groundwater. Common industrial chemicals that are characterized as chlorinated solvents include trichloro-ethene (TCE), 1,1,1-trichloroethane (TCA), tetrachloroethene (PCE) or perchloro-ethylene, chlorofluorocarbon (Freon)-113 (i.e., 1,1,2-trichloroethane or 1,2,2-tri-fluoroethane), and methylene chloride. In 1997, the EPA reported the presence of TCE and PCE in 852 of 945 groundwater supply systems throughout the United States and in 771 of 1420 Superfund sites. 

In our second example we consider the reduction of chlorinated ethenes including the prominent solvents tetrachloroethene (perchloroethylene, PCE) and trichloro-ethene (TCE). An overview of the hypothesized reaction sequence for reduction of these compounds by zero-valent iron (Fe(0) has been constructed (Fig. 14.15 Arnold and Roberts, 2000). Identical or very similar reaction schemes have been... 

Another inverse analytical technique was developed by Ala and Domenico [1] to determine parameters such as the source strength and size, and the advective position of the contaminant front for the instantaneous contaminant plumes at Otis Air Force Base (AFB), Massachusetts. The contaminant plumes contained chloride, biodegradable and nonbiodegradable detergents, trichloro-ethene, and tetrachloroethene. To obtain the uniquely determined parameters, Ala and Domenico structured the analytical technique to solve several equations simultaneously. By assuming a uniform vertical contaminant distribution, the steady state analytical solution becomes... 

The impact of deposition on global distribution has been noted for the CFC replacements hydro-chlorofluorocarbons (HCFCs), the chlorinated solvents tetrachloroethene (PCE), and trichloro-ethene (TCE), as these compounds undergo gas phase oxidation and photochemical degradation, resulting in the formation of carbonyl halides (e.g., CCI2O) and haloacetyl halides (e.g., bromo-, chloro-, and fluoroacetates). As these compounds are polar and water soluble, they are transported via aerosols, rain, and fog, which impacts their tropospheric lifetime and depositional fluxes (Rompp et al., 2001 de Bmyn et al., 1995). It is not clear whether and to what extent there is evidence of latitudinal fractionation of these compounds. 

Structural study of benzene, tetrachloroethene and trichloro-ethene sorbed phases in silicalite-1... 

F. Parsons, P.R. Wood, J. DeMarco, Transformations of tetrachloroethene and trichloro-ethene in microcosms and groundwater, J. Am. Water Works Assn. 76 (1984) 56-59. 

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