| 摘要 |
Carboxylic anhydrides such as benzoic anhydride and pivalic anhydride are prepared, without waste air and waste water, from the corresponding carboxylic acids and acetic anhydride. According to the invention, the reaction is carried out in a reaction/distillation apparatus (cf. Fig. 1) operated continuously or batchwise at normal pressure or reduced pressure with simultaneous separation of the reaction products carboxylic anhydride and acetic acid. <IMAGE> |
