Carbon tetrachloride degradation

Petrier C, Francony A (1997) Ultrasonic waste-water treatment incidence of ultrasonic frequency on the rate of phenol and carbon tetrachloride degradation. Ultrason Sonochem 4(4) 295-300... 

Halide-saturated hydrocarbons such as carbon tetrachloride degrade very slowly, if at all, when exposed to solar detoxification treatment. Bicarbonate, a common constituent of groundwater, acts as a scavenger of hydroxyl radicals and can significantly hinder solar detoxification treatment. The presence of nontargeted contaminants in process infiuent can lower process efficiency. 

It is important to note that in the presence of UV light that organotin com-pormds can degrade. Thus, in the presence of UV Ught, trimethyltin chloride in carbon tetrachloride degrades into inorganic tin via dimethyltin dichloride and methyltin trichloride. ... 

Degradation of carbon tetrachloride by photochemical, x-ray, or ultrasonic energy produces the trichloromethyl free radical which on dimeri2ation gives hexachloroethane. Chloroform under strong x-ray irradiation also gives the trichloromethyl radical intermediate and hexachloroethane as final product. 

The degradation of carbon tetrachloride to COj by a Pseudomonas sp. (Criddle et al. 1990), although a substantial part of the label was retained in nonvolatile water-soluble residues (Lewis and Crawford 1995). The nature of this was revealed by isolation of adducts with cysteine and N,N -dimethylethylenediamine in which intermediates formally equivalent to COCI2 and CSCI2 were trapped, presumably formed by reaction of the substrate with water and a thiol, respectively. Further consideration of these reactions is given in Chapter 7, Part 3. 

Francony A, Petrier C (1996) Sonochemical degradation of carbon tetrachloride in aqueous solution at two frequencies 20 kFIz and 500 kHz. Ultrason Sonochem 3(2) S77... 

Permethylated oligogermanes (9) and various photolysis degradation products (10) were scavenged with carbon tetrachloride and other agents and determined by GC-MS33. 

Carbon tetrachloride (5 and 10 mg/L) showed significant degradation with rapid adaptation in a static-culture flask-screening test (settled domestic wastewater inoculum) conducted at 25 °C. Complete degradation was observed after 14 d of incubation (Tabak et al., 1981). 

Van Eekert, M.H.A., Schroder, T.J., Stains, A.J.M., Schraa, G., andField,J.A. Degradation and fate of carbon tetrachloride in unadapted methanogenic grannlar slndge, Appl Environ. Microbiol, 64(7) 2350-2356, 1998. 

Johnson, T.L. Eish,W. GorhyYA. Tratnyek, P.G. (1998) Degradation of carbon tetrachloride by iron metal Complexation effects on the oxide surface. J. Contam. Hydrol. 29 379-398... 

Relative importance of covalent binding and lipid peroxidation in carbon tetrachloride-induced liver toxicity role of cell calcuim, protein and phospholipid degradation development of treatments/ antidotes. 

Carbon tetrachloride is a stable chemical that is degraded very slowly, so there has been a gradual accumulation of carbon tetrachloride in the environment as a consequence of releases from human activities. Until 1986, the largest source of release was from the use of carbon tetrachloride as a grain fumigant, but this practice has now been stopped. Other releases of carbon tetrachloride may occur during carbon tetrachloride production or during the use of carbon tetrachloride in the manufacture of chlorofluorocarbons and other chemical products. 

No studies were located on the degradation of carbon tetrachloride in soil or sediment. Based on the estimated aqueous aerobic biodegradation half-life of carbon tetrachloride the half-life of carbon tetrachloride in soil is estimated to be 6-12 months (Howard et al. 1991). 

For this reason, additional studies on carbon tetrachloride flux rates into and out of surface water, as well as refined quantitative estimates of aquatic fate processes would be valuable. The chemical is expected to evaporate rapidly from soil due to its high vapor pressure and may migrate into groundwater due to its low soil adsorption coefficient. No data are available on biodegradation in soil. Additional studies to determine degradation rates and the extent to which adsorption has occurred would be useful. These data are also useful in evaluating the impact of carbon tetrachloride leaching from hazardous waste sites. 

Seakins (16) has reported that the low temperature oxidation of propane is promoted by chloroform but not by carbon tetrachloride. Our studies, however, show that chloroform and carbon tetrachloride have generally similar effects on all preflame stages (Figure 3) and that their patterns of oxidative degradation are also similar (Figure 8). Under the conditions of Seakins experiments the following reaction, which he suggested, probably initiates the sequence of reactions responsible for promotion. 

Groundwater and Soil. Pumping out the liquid phase is an obvious first step if die contaminant is likely to be mobile, but in situ bioremediation is a promising option. Thus, the U.S. Department of Energy is investigating the use of anaerobic in situ degradation of carbon tetrachloride with nitrate as electron acceptor, and acetate as electron donor. 

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