摘要:
Disclosed is a method for jointly producing (i) formic acid (III); (ii) a carboxylic acid comprising at least two carbon atoms (II) and/or the derivatives thereof; and (iii) a carboxylic acid anhydride (VII). According to said method, (a) a formic acid ester (I) is transesterified to formic acid (III) and the corresponding carboxylic acid ester (IV) by means of a carboxylic acid comprising at least two carbon atoms (II); (b) at least one portion of the carboxylic acid ester (IV) formed in step (a) is carbonylated in order to obtain the carboxylic acid anhydride (V); and (c) at least one portion of the carboxylic acid anhydride (V) formed in step (b) is further dehydrated by means of a carboxylic acid (VI) so as to form a carboxylic acid anhydride (VII) and the carboxylic acid (II).