Trichlorobenzene s

4-Trichlorobenzene (1,2,4-TCB) is used as a solvent. According to Shelton (1989), it is formed in small quantities during the chlorination of drinking water. Chronic exposure can adversely affect various organs. 

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Tetrachloroethylene, 494 Total dissolved solids, 491 Toxaphene, 495 Trichlorobenzene(s), 494 Trichloroethylene, 494 Trihalomethanes (TTHMs), 479, 511... 

Dichlorobenzene. T -Dichlorobenzene s largest and growing oudet is in the manufacture of poly(phenylene sulfide) resin (PPS). Other apphcations include room deodorant blocks and moth control, a market which is static and likely to remain unchanged but combined is currently a larger outlet than PPS. Small amounts ofT -dichlorobenzene are used in the production of 1,2,4-trichlorobenzene, dyes, and insecticide intermediates. Exports have been a principal factor in U.S. production with about 25% exported in 1988. 

Bis-(methylthio)-l,3,2X, 4X -dithiadiphosphetane-2,4-dithione (Davy s reagent) [82737-61-9] M 284.4, m 160°. Recrystd from C6H6 in yellow plates or from hot trichlorobenzene. The low m observed in the literature (112° with gradual softening at 68-102°) has been attributed to the presence of elemental sulfur in the crystals. [Tetrahedron 40 2663 1984 J Org Chem 22 789 1957.]... 

Van der Schalie, W.H. The Acute and ChronicToxicity of 3,5-Dinitroaniline, 1,3-Dinitrobenzene, and 1,3,5-Trichlorobenzene to Freshwater Aquatic Organisms, U.S. Army Medical Bioengineering Research and Development Laboratory, Fort Detrick, MD, Technical Report 8305 (1983), 53 p. 

A reliable procedure for determination of molecular parameters number, weight and z-averages of the molecular weight (Mj, i = n, w and z respectively) for polyethylenes, PE, by means of Size Exclusion Chromatography, SEC, has been developed. The Waters Sci. Ltd. GPC/LC Model 150C was used at 135 C with trichlorobenzene, TCB, as a solvent. The standard samples as well as commercial stabilized and not stabilized PE-resins were evaluated. The effects of sampling, method of solution preparation, addition of antioxidant(s), thermal and shear degradation were studied. The adopted procedure allows reproducible determination of and M , with a random error of 4% and M2, with 9%, within 2 to 72 hrs from the initial moment of preparation of solutions. 

Masten S J, Galbraith MJ, Davies S HR (1993) Oxidation of Trichlorobenzene Using Advanced Oxidation Processes, Ozone in Water and Wastewater Treatment, 1 llh Ozone World Congress, 20/45-20/49. 

A solution of propanoic acid (5.92 g, 80mmol) in 1,2,4-trichlorobenzene (80 ml) was heated at 80-100°C. Davy s methyl reagent (12.6 g, 44 mmol), prepared according to [142], was added portionwise in 2 min. The mixture was heated at 140°C during 10 min (caution operate under a hood and trap obnoxious vapours by bleach). It was then cooled to room temperature. The liquid which separated was distilled to give yellow methyl propanedithioate (5.93 g, 49 mmol, 61%), b.p. 57°C/12 torr. 

Laboratory. The preferred lab prepn consists of the nitration of s-trichlorobenzene with a mixt of nitric acid and oleum at a temp of... 

Solvent polarity influences the rate of copolymerization. Thus with increasing dielectric constant of the solvent, the copolymerization rate rises as a result of the increase in the dissociation constants of the active species. The apparent rate constant for the copolymerization of 2-hydroxy-4-(2,3-epoxypropoxy)benzophenone with phthalic anhydride, initiated by hexadecyltrimethylammonium bromide56), increases from 4.65 x 10 4 s 1 in o-xylene to 6.84x 10 4 s-1 in nitrobenzene. Hilt et al.S4) proposed a suitable model illustrating the effect of solvent polarity in the copolymerization of phthalic anhydride with ethylene glycol carbonate in a mixture of nitrobenzene and trichlorobenzene (Table 4). With increasing fraction of the more polar nitrobenzene, the rate of copolymerization increases. 

Higher concentrations of H202 increase the concentration of hydroxyl radicals. In other words, the higher system redox potential may increase the oxidation state on mineral surfaces (S i ), which might lead to oxidation of sorbed 1,3,5-trichlorobenzene, 1,2,3,4-tetrachlorobenzene, and pentachlo-robenzene ... 

The rate constant for OH radical addition cannot be calculated because the effect of the -OP(=S)(OCH2CH3)2 substituent is not known. However, because the rate constant for OH radical addition to pyridine is -3.7 x 10-13 cm3 molecule-1 s-1 (Atkinson, 1989) and the three Cl atom sustituents will markedly deactivate the ring (Brown and Okamoto, 1958) [as observed, for example, for the OH radical reactions with chlorobenzene, 1,2-, 1,3- and 1,4-dichlorobenzene, and for 1,2,4-trichlorobenzene relative to that for benzene (Atkinson, 1989)], OH radical addition to the pyridine ring is expected to be minor, and its neglect will lead to an estimated lower limit to the total reaction rate constant. 

Lowering the reaction temperature or adding urea or basic solvents decreases the extent of chlorination. Solvents such as nitrobenzene, trichlorobenzene, alcohols, glycols, pyridine, and aliphatic hydrocarbons are employed. By using substituted phthalic acids such as 4-chlorophthalic acid anhydride, 4-sulfophthalic acid anhydride, or 4-nitrophthalimide, phthalocyanines with inner substitution can be produced. The products can often be purified by sublimation in vacuo at 300-400 °C. Soluble Pc s can be purified by recrystallization. 

FIGURE 6.1.1.6.3 Logarithm of Henry s law constant, Kow and KOA versus reciprocal temperature for 1,2,4-trichlorobenzene. 

Oxidation rate constant k, for gas-phase second order rate constants, koH for reaction with OH radical, kNQ3 with N03 radical and k03 with 03 or as indicated, data at other temperatures see reference kon-LOx 10-13 cm3 molecule-1 s. residence time of 116 d, loss of 0.9% in one day or 12 sunlit hours at 300 K for trichlorobenzenes in urban environments (Singh et al. 1981) photooxidation t/2 = 6.17 months, based on a measured rate for the vapor phase reaction with photochemically produced hydroxyl radicals in air (Atkinson et al. 1985). 

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