PROCESS FOR THE OBTENTION OF WATER-FREE OR SUBSTANTIALLY WATER-FREE FORMIC ACID BY HYDRAULYSIS OF METHYL FORMIATE

摘要

1. A process for obtaining anhydrous or substantially anhydrous forming acid by hydrolysis of methyl formate using extracting agents consisting of carboxamides of the formula (l) see diagramm : EP0156309,P4,F1 where R**1 and R**2 are each alkyl, which may furthermore be joined together to form a 5-membered or 6-membered ring, or R**1 is hydrogen, and R**3 is hydrogen or C1 -C4 -alkyl and the sum of the carbon atoms in the radicals R**1, R**2 and R**3 is from 1 to 14, wherein a) methyl formate is hydrolyzed in the presence of a carboxamide of the formula l b) the mixture formed during the hydrolysis is separated into its individual components in a 1st distillation column (2) which is divided into a feed part and a take-off part by separating means which are effective in the longitudinal direction - the hydrolysis mixture (8) being fed into the feed part, - methanol and unreacted methyl formate being taken off as top product (5) and as a side product (10), - extracting agent and formic acid being taken off as an anhydrous or substantially anhydrous bottom product (9), and - water (6), preferably in liquid form, being removed from the take-off part, and c) the bottom product (9) form the 1st distillation column is separated, in a 2nd distillation column (3), into formic acid (11) and the extracting agent (4).