| 摘要 |
A batchwise or continuous process for producing isophthaloyl dichloride or terephthaloyl dichloride having a high purity which comprises, in combination, (1) a first step of producing alpha , alpha , alpha , alpha ', alpha ', alpha '-hexachloroxylene by reacting meta- or para-xylene with chlorine under the irradiation of ultraviolet-containing rays, the reaction being carried out in the presence of, as a solvent, alpha , alpha , alpha , alpha ', alpha ', alpha '-hexachloroxylene added at the outset of the reaction; (2) a second step of producing isophthaloyl dichloride or terephthaloyl dichloride by reacting the alpha , alpha , alpha , alpha ', alpha ', alpha '-hexachloroxylene obtained in the first step with isophthalic acid or terephthalic acid; and (3) a third step of purifying the isophthaloyl dichloride or terephthaloyl dichloride obtained in the second step by dissolving the isophthaloyl dichloride or terephthaloyl dichloride in 0.3 to 6 parts by weight; per part by weight of the phthaloyl dichloride, of C6-C10 aliphatic hydrocarbon solvent, and cooling the solution to a temperature of the specified range thereby to recrystallize the phthaloyl dichloride.
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