Pentachlorophenol decomposition products

Photodecomposition of pentachlorophenol was observed when an aqueous solution was exposed to sunlight for 10 d. The violet-colored solution contained 3,4,5-trichloro-6-(2 -hydroxy-3, 4, 5, 6 -tetrachlorophenoxy)-o-benzoquinone as the major product. Minor photo-decomposition products (% yield) included tetrachlororesorcinol (0.10%), 2,5-dichloro-3-hydroxy-6-pentachloro-phenoxy-p-benzoquinone (0.16%), and 3,5-dichloro-2-hydroxy-5-2, 4, 5, 6 -tetrachloro-3-hy-droxyphenoxy-p-benzoquinone (0.08%) (Plimmer, 1970). 

Work by Boule et a. (21, 22) and Wong and Crosby (23) have provided information on the photodecomposition products of chlorophe-nols. In the case of pentachlorophenol degradation products included tetrachlorophenols, trichlorophenols, chlorinated dihydroxy benzenes, and nonaromatic fragments such as dichloromaleic acid (23). Other than CO2 which came from photo-mineralization, we did not attempt to identify the products of pentachlorophenol decomposition in our experiments. Boule (22) found that 2,4-dichlorophenol... 

The other example, a polymer-bound fungicide, is found in the copolymerization of pentachlorophenyl acrylate with vinyl acetate and ethyl acrylate. This pentachlorophenol-based product could have use as an anti-fouling agent in marine coatings. In this case it was necessary to copolymerize with ethyl acrylate. The homopolymer was found to be too hydrophobic to allow decomposition of the polymer and allow release of the active agent in sufficiently high concentrations to have the appropriate biocide effect. 

The decomposition of benzene and naphthalene and its homologues by microorganisms has already been discussed earlier. The metabolizing mechanisms of naphthalenes in fish have been well studied [47, 49]. Decomposition products of chlorobenzene in daphnia, mosquitos, snails and fishes are the polar compounds chlorophenol and chloro-o-dihydroxybenzene amongst other compounds, those of nitrobenzene aniline, acetanilide, aminophenols and nitrophenols and those of hexachlorobenzene pentachlorophenol and unknown compounds [71]. Bromoben-zene is deactivated to the toxic bromophenol [217]. In the case of man and land mammals, studies have concentrated on the metabolism of benzene, toluene, xylenes and styrene, which are also significant in occupational medicine [12, 13, 136, 195, 196, 215-217], A comparison of the metabolism of benzene into phenol in various animal species with the aid of microsomal preparations of the lungs or liver yielded vast differences. However, it is possible for benzene, in part, to inhibit or prevent its own metabolism [218]. 

This technology can remove oily sludges, pesticides, herbicides, pentachlorophenol, polychlorinated biphenyls (PCBs), coal by-products, wood treating compounds, dioxins, and furans. It is often used in conjunction with the company s base-catalyzed decomposition (BCD) process. The BCD process is designed to treat chlorinated compounds. 

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