Chlorine dioxide phenols

At present, chlorine dioxide is primarily used as a bleaching chemical in the pulp and paper industry. It is also used in large amounts by the textile industry, as well as for the aching of flour, fats, oils, and waxes. In treating drinking water, chlorine dioxide is used in this country for taste and odor control, decolorization, disinfection, provision of residual disinfectant in water distribution systems, and oxidation of iron, manganese, and organics. The principal use of chlorine dioxide in the United States is for the removal of taste and odor caused by phenolic compounds in raw water supplies. 

Oxidation of phenols with chlorine dioxide or chlorine produces chlorinated aromatic intermediates before ring rupture. Oxidation of phenols with either chlorine dioxide or ozone produces oxidized aromatic compounds as intermediates which undergo ring rupture upon treatment with more oxidant and/or longer reaction times. In many cases, the same nonchlorinated, ringruptured aliphatic products are produced using ozone or chlorine dioxide. 

Wajon JE, Rosenblatt DH, Burrows EP. 1982. Oxidation of phenol and hydroquinone by chlorine dioxide. Environ Sci Technol 16 396-402. 

Wet oxidation of phenol at elevated pressure and temperature gave the following products acetone, acetaldehyde, formic, acetic, maleic, oxalic, and succinic acids (Keen and Baillod, 1985). Chlorine dioxide reacted with phenol in an aqueous solution forming p-benzoquinone and hypochlorous acid (Wajon et al., 1982). 

This is a process for destruction of microorganisms. Chlorine, hypochlorite salts, phenol, phenol derivatives, ozone, salts of heavy metals, chlorine dioxide, and so on are effective disinfectants. It may require pH adjustments. 

Musil J, Knotek Z, Chalupa J, et al. 1964. Toxicologic aspects of chlorine dioxide application for the treatment of water containing phenols. Sb Vys Sk Chem Technol Praze Oddil Fak Technol Paliv Vody 8 327-345. 

Tratnyek PG, Hoigne J. 1994. Kinetics of reactions of chlorine dioxide (OCIO) in water—II. Quantitative stmcture-activity relationships for phenolic compounds. Water Res 28(l) 57-66. 

A more permanent removal of color has been described by Lin (6), and by Dilling and Sarjeant (7), for lignin derivatives in which the phenolic functionality has been partially blocked. These largely non-phenolic (and sulphonated) lignin derivatives were bleached in homogeneous aqueous phase with hydrogen peroxide and chlorine dioxide. Reductions in color of 80-93% were reported for these water soluble derivatives (6,7). 

Chlorination can result in unacceptable taste intensification, where potable water is concerned. This often originates in the chlorination of phenols present in trace amounts from industrial pollution. If economics permit, use of chlorine dioxide (Section 12.2) or ozone (Section 8.3) in place of chlorine will minimize taste intensification and will also avoid formation of carcinogenic chlorocarbons, notably chloroform. These carcinogens may form from chlorination of contaminants such as acetone, a commonly used solvent that finds its way into water supplies ... 

Tratnyek and Hoigne (1994) investigated 25 substituted phenoxide anions for QSARs that can be used to predict rate constants for the reaction of additional phenolic compounds oxidized by chlorine dioxide (OCIO). Correlating oxidation rates of phenols in aqueous solution is complicated by the dissociation of the phenolic hydroxyl group. The undissociated phenol and the phenoxide anion react as independent species and exhibit very different properties. The correlation analysis should be performed on the two sets of rate constants separately. 

Martinez GR, Medeiros MHG, Ravanat J-L, Cadet J, Di Mascio P (2002) [0ls]-Labeled singlet oxygen as a tool for mechanistic studies of 8-oxo-7,8-dihydroguanine oxidative damage detection of spiroiminodihydantoin, imidazolone and oxazolone derivatives. Biol Chem 383 607-617 Martini M, Termini J (1997) Peroxy radical oxidation of thymidine. Chem Res Toxicol 10 234-241 Merenyi G, Lind J, Shen X (1988) Electron transfer from indoles, phenol, and sulfite (S032T to chlorine dioxide (CICV). J Phys Chem 92 134-137... 

Aside from oxygen and the activated oxygen species,there are several other oxidants that cause abiotic oxidation reactions involving environmental contaminants. In engineered systems, these include chlorine (49), chlorine dioxide (50-52), permanganate (53, 54) and ferrate (55, 56). At highly contaminated sites, anthropogenic oxidants such as chromate, arsenate, and selenate may react with co-contaminants such as phenols (57, 58). 

Thielemann [105] has used thin layer chromatography to study the effect of chlorine dioxide on 1- and 2-naphthols in potable water. The coloured products obtained are thought to be condensation products of chloroderivatives of 1,2- or 2,6-naphthaquinone. Thielemann applied paper chromatography to a study of the reaction products of polyhydric phenols with chlorine dioxide. 

Although the free phenolic structures are oxidized faster, chlorine dioxide also destroys nonphenolic phenyl propane units and double bonds present in the pulp chromophores. After cleavage of the benzene ring various di-carboxylic acids are formed, such as oxalic, muconic, maleic, and fumaric acids in addition to products substituted with chlorine (Fig. 8-10). As a result of depolymerization and formation of carboxyl groups the modified lignin is dissolved during the chlorine dioxide treatment and in the sodium hydroxide extraction stage that usually follows. 

Tratnyek, P. G., and Hoigne, J. (1994) Kinetics of Reactions of Chlorine Dioxide in Water—II Quantitative Stmcture-Activity Relationships for Phenolic Compounds. Water Res. 28, 57-66. 

The Baxter Water Treatment Plant, Philadelphia, Pennsylvania, is a 12.35-m /s (282-MGD) conventional water treatment plant built in 1960. The plant supphes drinking water from the Delaware River to a population of over 800,000. Chemicals used in treatment include chlorine, ferric chloride or ferrous sulfate, hme, fluoride, and ammonia. Powdered activated carbon is used on demand for control of taste and odor, and chloride dioxide is used for control of THMs, tastes, and odors. The chlorine dioxide system was left over from the previous water treatment plant on that site. In the 1950s, it was used to oxidize phenolic compounds found in the watershed, which have since been eliminated. 

Vella PA, Munder JA. 1993. Toxic pollutant destruction Comparison of the oxidants potassium permanganate, Fenton s reagent, and chlorine dioxide on the toxicity of substituted phenols. ACS Symp Ser 518(Em) 85-105. 

Chlorine dioxide in water samples has been determined by FIA method employing preliminary separation (using a purge-trap system with N2 purge gas) and 4-aminoantipyrine and phenol [4]. Detection limit was 5 ppb. 

In other work related to bleaching chemistry, the reactions of chlorine dioxide with monomeric [44] and dimeric [45] lignin model compounds have been studied computationally. These studies closely parallel experimental work in which oxidation mechanisms were proposed [46-51]. In accord with the experimental work, which reports higher reactivity of phenolic compounds, the heats of reaction for these compounds are lower than those for etherified models. The experimentally based mechanisms were generally found to be energetically feasible, but in some cases the electronic results were not consistent with the proposed mechanisms. 

Ni, Y, X. Shen, and A. R. P. van Heiningen. 1994. Studies on the reactions of phenolic and non-phenolic lignin model compounds with chlorine dioxide. J. Wood Sci. Technol. 14 243-262. 

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