| 摘要 |
The invention concerns a semi-continuous method for preparing acid chlorides and benzene aldehydes which consists in: producing in a reactor a starter comprising for the major part a dichloromethylated benzene compound; simultaneously and continuously introducing simultaneously in the reactor, a carboxylic acid or its anhydride, a dichloromethylated benzene compound (2) and at least a Friedel-Crafts catalyst; and in causing them to react, under stirring, under a pressure P1 not higher than atmospheric pressure and at a temperature ranging between 60 DEG C and 180 DEG C; continuously extracting chloride acid (3) from the reaction medium and optionally formed HCI, by distillation under pressure P1 and at reaction temperature, then in ceasing to introduce reagents when the working volume of the reactor containing for the major part benzene aldehyde is reached; and in performing total or partial fractionated distillation of the reaction medium, consisting for the major part of benzene aldehyde, under pressure P2 < P1 and at a temperature not higher than 180 DEG C.
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