Process for the production of fluorocarboxylic acid anhydrides

摘要

The present invention relates to a process for the coproduction of trifluoroacetic anhydride (TFAA) and a carboxylic anhydride having the formula ÄR-C(O)Ü2O which comprises the steps of: (1) preparing a mixed anhydride having the formula R-C(O)-O-C(O)-CF3 in a reaction vessel; (2) removing the mixed anhydride from the reaction vessel and introducing it into the mid-section of a reactive distillation column wherein the mixed anhydride disproportionates to form TFAA and ÄR-C(O)Ü2O; (3) removing a lower boiling product comprising TFAA from the upper section of the reactive distillation column; and (4) removing a higher boiling product comprising ÄR-C(O)Ü2O from the lower section of the reactive distillation column; wherein R is an alkyl, alkenyl, cycloalkyl or aryl group containing up to 6 carbon atoms.