Chlorination: of acetic acid

Other acetyl chloride preparations include the reaction of acetic acid and chlorinated ethylenes in the presence of ferric chloride [7705-08-0] (29) a combination of ben2yl chloride [100-44-7] and acetic acid at 85% yield (30) conversion of ethyUdene dichloride, in 91% yield (31) and decomposition of ethyl acetate [141-78-6] by the action of phosgene [75-44-5] producing also ethyl chloride [75-00-3] (32). The expense of raw material and capital cost of plant probably make this last route prohibitive. Chlorination of acetic acid to monochloroacetic acid [79-11-8] also generates acetyl chloride as a by-product (33). Because acetyl chloride is cosdy to recover, it is usually recycled to be converted into monochloroacetic acid. A salvage method in which the mixture of HCl and acetyl chloride is scmbbed with H2SO4 to form acetyl sulfate has been patented (33). 

Manufacture. Most chloroacetic acid is produced by the chlorination of acetic acid using a suitable catalyst such as acetic anhydride (9—12). The remainder is produced by the hydrolysis of trichloroethylene with sulfuric acid (13,14) or by reaction of chloroacetyl chloride with water. 

Trichloroacetic acid is manufactured in the United States by the exhaustive chlorination of acetic acid (38). The patent Hterature suggests two alternative methods of synthesis hydrogen peroxide oxidation of chloral (39) and hydrolytic oxidation of tetrachloroethene (40). 

Chlorination of of a-Keto Compounds Investigated in Micro Reactors Cas/liquid reaction 14 [CL 14] Chlorination of acetic acid... 

Electrochemical reduction in aqueous acid is useful in the treatment of waste liquors obtained from the formation of chloroacetic acid by chlorination of acetic acid. The liquors contain further chlorination products. These are reduced in an undivided cell at a magnetite cathode and a carbon anode to give excellent conversion to monochloroacetic acid [73]. 

Chloroacetic Acid (ClCHiCOOHf. [CAS 79-11-8 J. Chloroacelic acid can be synthesized by the radical chlorination of acetic acid, treatment of trichloroethylene with concentrated H S04. oxidation of 1.2-dichloro ethane or chloroaceialdehyde. amine displacement from glycine, or chlorination of ketene. It behaves as a very strong monobasic acid and is used as a strong acid catalyst for diverse reactions. The Cl function can be displaced in base-catalyzed reactions. For example, it condenses with alkoxides to yield alkoxyacetic acids CICH COOH... 

The multiple chlorination of another activated compound, phenoxyacetic acid, leads to a useful product. This compound is made industrially by an S>j2 reaction (Chapter 17) on chloroacetic acid (made by chlorination of acetic acid, Chapter 21) with phenol in alkaline solution. Reaction occurs at the oxygen atom rather than on the ring. 

Direct chlorination of acetic acid in the presence of a small quantity of red phosphorus is a standard procedure for the preparation of chloro-acetic acid however, similar treatment of its straight-chain homologs gives complex mixtures of halogenated acids. Substitution by chlorine in a btanched-chain acid such as isovaleric acid occurs largely at the tertiary hydrogen. The peroxide-catalyzed chlorination of aliphatic acids... 

Chlorination of acetic acid to obtain moncM ltloracetic acid, according to the equation... 

A great advantage of electrochemical reactions compared with chemical conversions is the effective contribution to pollution control. The direct electron transfer from the electrode to the substrate avoids the problem of separation and waste treatment of the frequently toxic end products of the chemical oxidants or reductants. Furthermore, by electrodialysis, organic acids or bases can be regenerated from their salts without the use of sulfuric acid or sodium hydroxide, for example, which lead to the coproduction of sodium salts or sulfates as waste [79]. At the same time, inorganic acids and bases, necessary for chemical production, are provided by this process. An application of electrodialysis has been demonstrated in the preparation of methoxyacetic acid by oxidation of methoxyethanol at the nickel hydroxide electrode [80]. Finally, unwanted side products can be converted into the wanted product, which increases the economy of the process and reduces the problem of waste separation and treatment. This is accomplished in the manufacture of chloroacetic acid by chlorination of acetic acid. There the side product dichloroacetic acid, formed by overchlorination, is cathodically converted to chloroacetic acid [81]. 

Applications Disulfur dichloride is utilized in the manufacture of sulfur dichloride, thionyl chloride and sulfur tetrafluoride and with polyols for the production of additives for high pressure lubricating oils and cutting oils. In addition it is used as a catalyst in the chlorination of acetic acid. Solutions of sulfur in disulfur dichloride is utilized in the room temperature vulcanization of rubbers. 

Derivation Chlorination of acetic acid in presence of iodine. 

Chlorination reactions are also highly exothermic and the use of microflow systems is quite effective for conducting the reaction in a controlled manner. Various chlorination reactions including chlorination of toluene derivative to obtain benzyl chlorides, chlorination of acetic acid to obtain chloroacetic acid, and radical chlorination of alkanes using microflow systems have been reported. 

The sodium salt of monochloroacetic acid, prepared by the hydratation of trichloroethylene or by the chlorination of acetic acid, is used for the selective control of grass weeds in maize, potato and onion crops. 

Trichloroacetic acid is prepared by the catalytic chlorination of acetic acid. Iodine, sulfur, phosphorus trichloride or their mixtures are used as catalyst ... 

Chhrodcetic Anhydride as Catalyst At the Gersthofen plant of I.G. Farbenindustrie, chloroacetic acid was made by the chlorination of acetic acid, using chloroacetic anhydride CH2C1CO-O CO CH8 as a catalyst. The catalyst was formed in situ by the action of SCI2. The process is cyclic and may be represented diagrammatically as follows ... 

Chloroacetic Acid, CH2CI.COOH, is prepared by the chlorination of acetic acid, acetyl chloride, or acetic anhydride... 

The microstructured falling film reactor has also been used for chlorination reactions [77]. Chlorination of acetic acid at a temperature over 140 C was carried out and the by-product (dichloroacetic acid) was reduced significantly, meaning that there is no need for additional costly and time-consuming separation processes. Further, a photochemical gas-liquid reaction by the selective photochlorination of toluene-2,4-diisocyanate (TDl) was demonstrated [78]. 

S., and Pechatschek, R. (2000) Monochloroacetic acid production by high temperature chlorination of acetic acid with chlorine 83. WO Patent 200210094-A DE Patent 10036603-Al WO Patent 200210094-Al. 

Chlorination of acetic acid Falling film MSR Wehle et al. [32]... 

Monochloroacetic acid is, for instance, used in the synthesis of cellulose derivatives (such as CMC). Monochloroacetic acid is produced by the chlorination of acetic acid in the presence of a homogeneous catalyst dissolved in the liquid phase, such as acetyl chloride ... 

Martikainen, R, Salmi, T., Paatero, E., Hummelstedt, L., Klein, R, Damen, H., and Lindroos, T., Kinetics of the homogeneous catalytic chlorination of acetic acid, J. Chem. Technol. Biotechnol, 40,259-274,1987. 

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