Chlorinated carboxylic acids, determination

Other organic compounds that have been determined in sewage effluents include the following (see Table 15.13) hydrocarbons, alcohols, carboxylic acids, esters, chlorobenzenes, nitrosamines, ethylene diamine tetraacetic acid, nitriloacetic acid, organophosphorus compounds, linear alkyl benzene sulphonates, methyl mercaptan, polychlorobiphenyls and chlorinated insecticides. 

Gas chromatography has been applied to the determination of a wide range of organic compounds in trade effluents including the following types of compounds which are reviewed in Table 15.15 aromatic hydrocarbons, carboxylic acids aldehydes, non ionic surfactants (alkyl ethoxylated type) phenols monosaccharides chlorinated aliphatics and haloforms polychlorobiphenyls chlorlignosulphonates aliphatic and aromatic amines benzidine chloroanilines chloronitroanilines nitrocompounds nitrosamines dimethylformamide diethanolamine nitriloacetic acid pyridine pyridazinones substituted pyrrolidones alkyl hydantoins alkyl sulphides dialkyl suphides dithiocaibamate insecticides triazine herbicides and miscellaneous organic compounds. 

In the disinfection process of drinking water, besides other chlorinated compounds, halogenated carboxylic acids arise. For quality control of drinking water the determination of these contaminants was established using LC-MS with a preference for ESI (cf 15.3.3.2 ESI, haloacetic acids). An application of APCI-MS for haloacetic acid analysis was reported after CE separation in a non-aqueous medium [303]. 

In the chlorination of carboxylic acids, it is important to know the diffusion coefficient of chlorine gas in the liquid phase. It is thus possible to determine how the reaction is affected by the diffusion of chlorine in the liquid film. Here, we will estimate the diffusion coefficient of chlorine in acetic acid. The association factor of acetic acid can be assumed to be equal to two. 

The procedure can be extended to achieve selective a-bromination and iodination of carboxylic acids and the general mechanism of the a-halogenation is outlined in Chapter 5, p 170. The autocatalytic effects in the selective a-chlorination of propionic acid to the 2-chloro and 2,2-dichloro acids have been studied in a semibatch reaction at 90-130 °C. The reaction was performed in the presence of chlorosulfonic acid and dichloroacetic acid as catalysts and oxygen as the radical scavenger. Kinetic experiments indicated autocatalytic formation of both products and that the selectivity was independent of the chlorine concentration in the liquid phase. The results confirmed the validity of the proposed reaction scheme which involved formation of the reaction intermediate, propanoyl chloride from propionic acid and chlorosulfonic acid, the acid-catalysed enolization of the acid, and a hydroxyl-chlorine exchange reaction. The acid-catalysed enolization was the rate-determining step in the reaction sequence. ... 

Storage Refrigerate store under nitrogen store in well-ventilated area away from incompat. substances keep away from heat, sparks, flame Uses Chlorinated solvent solvent for hard resins, nitrocellulose reactive chloro intermediate for the modification of amines, alcohols, and carboxylic acids C3-building block mfg. of photographic and Zapon lacquer cement for celluloid binder for water colors in determination of Vitamin A intermediate in organic synthesis in paints, varnishes, lacquers Regulatory Canada DSL... 

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