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Phenol chlorinated

The cleavage products of several sulfonates are utilized on an industrial scale (Fig. 3). The fusion of aromatic sulfonates with sodium hydroxide [1310-73-2J and other caustic alkalies produces phenohc salts (see Alkylphenols Phenol). Chlorinated aromatics are produced by treatment of an aromatic sulfonate with hydrochloric acid and sodium chlorate [7775-09-9J. Nitriles (qv) (see Supplement) can be produced by reaction of a sulfonate with a cyanide salt. Arenesulfonates can be converted to amines with the use of ammonia. This transformation is also rather facile using mono- and dialkylamines. [Pg.96]

The light chlorophenols, normally have a purity greater than 98.5%, but they often reach over 99%, or even 99.5% with direct phenol chlorination. The APHA color test is always below 100. For 2,4,6-ttichlorophenol, the 2,4,5-trichlorophenol content constitutes an essential quaUty index and should be under 20 mg/kg. None of the light chlorophenols contain any polychlorodibenzoparadioxins or polychlorodibenzofurans. [Pg.80]

As recently as 1970, only about 30 naturally occurring organohalogen compounds were known. It was simply assumed that chloroform, halogenated phenols, chlorinated aromatic compounds called PCBs, and other such substances found in the environment were industrial pollutants. Now, only a third of a century later, the situation js quite different. More than 5000 organohalogen compounds have been found to occur naturally, and tens of thousands more surely exist. From a simple compound like chloromethane to an extremely complex one like vancomycin, a remarkably diverse range of organohalogen compounds exists in plants, bacteria, and animals. Many even have valuable physiological activity. Vancomycin, for instance, is a powerful antibiotic produced by the bacterium Amycolatopsis orientalis and used clinically to treat methicillin-resistant Staphylococcus aureus (MRSA). [Pg.351]

This group of pesticides comprises different families of chemicals with her-bicidal action including substituted phenols, chlorinated aliphatic acids, chloro-phenoxy alkanoic acids, and substituted benzoic acids, which possess carboxyl or phenolic functional groups capable of ionization in aqueous media to yield anionic species [47,151,168-170]. [Pg.27]

Renner, G. Gas chromatographic studies of chlorinated phenols, chlorinated anisoles, and chlorinated phenylacetates, Toxicol Environ. Chem., 27 217-224, 1990. [Pg.1714]

Supercritical C02 has also been tested as a solvent for the removal of organic contaminants from soil. At 60°C and 41.4 MPa (6,000 psi), more than 95% of contaminants, such as diesel fuel and polychlorinated biphenyls (PCBs), may be removed from soil samples (77). Supercritical C02 can also extract from soil the following hydrocarbons, polyaromatic hydrocarbons, chlorinated hydrocarbons, phenols, chlorinated phenols, and many pesticides (qv) and herbicides (qv). Sometimes a cosolvent is required for extracting the more polar contaminants (78). [Pg.226]

Polychlorinated Dibenzo-(p)-Dioxins and Dibenzo-Furans. Another group of compounds that we need to specifically address are the polychlorinated dibenzo-p-dioxins (PCDDs) and dibenzo-furans (PCDFs) (Fig. 2.15). The PCDDs and PCDFs are not intentionally produced but are released into the environment from various combustion processes and as a result of their occurrence as unwanted byproducts in various chlorinated chemical formulations (e.g., chlorinated phenols, chlorinated phenoxy herbicides see Alcock and Jones, 1996). Because some of the PCDD and PCDF congeners are very toxic (e.g., 2,3,7,8-tetrachloro dibenzo-p-dioxin, see margin), there have been and still are considerable efforts to assess their sources, distribution, and fate in the environment. Similarly to the PCBs or DDT (see above), the PCDDs and PCDFs are highly hydrophobic and very persistent in the environment. It is therefore not surprising that they have also been detected everywhere on earth (Brzuzy and Hites, 1996 Lohmann and Jones, 1998 Vallack et al., 1998). Finally, we should note that polybrominated diphenylethers (PBDEs, see margin) that, like the PBBs (see above), are used as flame retardants, are of increasing environmental concern (de Boer et al., 2000). [Pg.41]

The regioselectivity in certain aromatic chlorinations by hypochlorite is also pH-depen-dent. The ortho/para ratio in phenol chlorination increased from 0.64 at pH = 4 to 4.3 at pH = 10794. Selective 4-chlorination of phthalic acid is obtained in aqueous sodium hypochlorite solution795. Iodination of phenols in aqueous systems is also pH-dependent and the ortho iodophenol yield grows at stronger basic media796,797. [Pg.580]

Chlorinated Hydrocarbons Other Chlorinated Compounds. The substitution of chlorine atom for hydrogen in a compd greatly increases the anesthetic action of the derivative. In addn, the chlorine deriv is less specific than the parent hydrocarbon in its action, and may affect other tissues along with those of the central nervous system of this body. The chlorine deriv is generally quite toxic and may cause liver, heart Sc kidney damage. As a rule, unsaturated chlorine derivs are highly narcotic but less toxic than saturated derivs. Sax(Ref 4) has discussed in detail the toxicities Sc hazards of a number of chlorinated compds, including Chlorinated Diphenyls Chlorinated Hydrocarbons, Aromatic Aliphatic Chlorinated Naphthalenes Chlorinated Phenols Chlorinated Triphenyls others. [Pg.23]

Trifluoro methyl phenol Chlorine + methyl phenol - trichloromethyl phenol + HF... [Pg.1062]

More than 100 substances in urine or blood are subject to a large-scale monitoring program (CDC 2005), and more than 100 phenolic chlorinated or brominated substances have been detected in human blood in Sweden (Hovander et al. 2002). [Pg.183]

Remarks. All chloro derivatives of phenol are converted to chloranil by the above procedure. The process, therefore, offers a possibility for using the byproducts of phenol chlorination (page 145) which are often difficult to dispose of because of their poisonous nature and offensive odor. [Pg.88]

Dioxins and furans are not produced deliberately, but are produced unintentionally as byproducts of combustions of organic matter in the presence of chlorine. Dioxins and fiirans consists of 135 possible chlorinated dibenzoftnan and 75 chlorinated dibenzo-p-dioxins with Irom 1 to 8 chlorine substituents (Figure 18.2). PCDDs/DFs are found as byproducts during the manufacture of some industrial chemicals such as PCBs, polychlorinated naphthalenes, chlorinated phenols, chlorinated phenoxyacids, polychlorinated diphenyl ethers, polyvinyl chlorides, and chlorinated phenoxy-2-phenols (Hutzinger et al, 1985 Hryhorczuk et al, 1986 ATSDR, 2001 Masunaga et al. [Pg.245]

Xenobiotic organic compounds (XOCs) originating from household or industrial chemicals and present in relatively low concentrations in the leachate (usually less than ImgL of individual compounds). These compounds include, among others, a variety of aromatic hydrocarbons, phenols, chlorinated aliphatic hydrocarbons, and pesticides. [Pg.5115]

Pulp and paper mill sludge is a complex and changeable mixture of dozens or even hundreds of compounds. Some are well known, like natural wood extractives, organochlorines, organosulfides, and dioxins. Priority pollutants and chemicals of concern that must be analyzed in pulp mill residues include heavy metals, chlorinated hydrocarbons, chlorobenzenes, PAHs, chlorinated phenols, chlorinated catechols, chlorinated guaiacols, phthalates, resin acids, alkylphenols and alkylphenol ethoxylates, and plant sterols. [Pg.528]

A phenol derivative, phenolphthalein is prepared by the reaction of phenol with phthalic anhydride in the presence of sulphuric acid and used as an indicator for acidity or alkalinity. Chlorinated phenol is much safer than phenol. Chlorine gas reacts with phenol to add one, two or three chlorine atoms and to form, respectively, chlorophenol, 2,4-dichlorophenol and 2,4,6-trichlorophenol . The chlorination of phenol proceeds by electrophilic aromatic substitution. The latter two molecules are less soluble in water than phenol and appear to be a stronger antiseptic than phenol. Interestingly, in the first half of the past century, a bottle of antiseptic chlorophenols was a common attribute as a medicine in many homes. Its solution was used for bathing cuts, cleaning grazes, rinsing the mouth and gargling to cure sore throats. Nevertheless, it was revealed that its solution likely contains dioxins. [Pg.12]

General rules were established at the beginning of the INN Program in order to allow health professionals to understand the rationale for a number of new names for pharmaceutical substances. At first some countries used shortened chemical names as generic names, but this system was found to be very limited, since many molecules contain similar elements and groups, such as phenol, chlorine, methyl, or benzyl-rings, in their chemical structures. In addition, in most... [Pg.869]

The strong electron-donating properties of —OH groups substituted on the aromatic ring render polyphenols very susceptible to oxidation in soils. On the other hand, phenols chlorinated at the para position, many examples of which are found among the pesticides or decomposition products of pesticides, are resistant to oxidation and can persist in soils for some time. However, phenols substituted at several positions on the ring with chlorine can be more susceptible to degradation by Mn oxides... [Pg.384]

Chlorinated phenols Chlorinated pesticides Arsenic Chromium(vi)... [Pg.184]


See other pages where Phenol chlorinated is mentioned: [Pg.34]    [Pg.106]    [Pg.465]    [Pg.105]    [Pg.102]    [Pg.492]    [Pg.100]    [Pg.24]    [Pg.349]    [Pg.387]    [Pg.695]    [Pg.1062]    [Pg.362]    [Pg.337]    [Pg.345]    [Pg.768]    [Pg.351]    [Pg.3865]    [Pg.24]    [Pg.805]    [Pg.376]    [Pg.396]    [Pg.351]    [Pg.243]    [Pg.1349]   
See also in sourсe #XX -- [ Pg.11 ]

See also in sourсe #XX -- [ Pg.257 , Pg.258 , Pg.259 , Pg.260 , Pg.261 , Pg.262 , Pg.263 , Pg.264 ]




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Bioremediation of chlorinated phenols

By chlorination phenol

Chlorinated aromatic compounds phenols

Chlorinated phenolics

Chlorinated phenolics

Chlorinated phenolics analytical methods

Chlorinated phenols application

Chlorinated phenols biodegradation

Chlorinated phenols chemical/physical properties

Chlorinated phenols environmental concern

Chlorinated phenols mechanisms

Chlorinated phenols obtained

Chlorinated phenols points

Chlorinated phenols relationship

Chlorinated phenols separation

Chlorinated phenols structures

Chlorinated phenoxy-2-phenols

Chlorination of phenol

Chlorination phenol-assisted

Chlorination phenol-directed

Chlorine dioxide phenols

Chlorine dioxide reaction with phenols

Chlorine phenols

Chlorine phenols

Extraction chlorinated phenol

GUY - LEMAIRE - GUETTE Phenol chlorination

Groundwater chlorinated phenol-contaminated

Nuclear Chlorine, Bromine or Fluorine from a Phenolic Ether

Oxidation chlorinated phenols

Phenol chlorination with

Phenols chlorinated, antiseptic/disinfectant

Phenols, chlorinated exposure

Sediments chlorinated phenol-contaminated

Water chlorinated phenol contamination

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