| abstract |
Process for the production of anhydrous or largely anhydrous formic acid by hydrolysis of methyl formate, where a) methyl formate is hydrolyzed in the presence of a carboxamide of the general formula I <IMAGE>, R 1 and R 2 being alkyl groups which are also linked to form a 5 or 6-membered ring may be, or R¹ is hydrogen and R³ is hydrogen or a C1-C4-alkyl radical, and the sum of the C atoms in the radicals R¹-R³ is 1 to 14, b) the hydrolysis mixture resulting from the hydrolysis in a 1st distillation column ( 2), which is divided into a feed and a take-off part by means of longitudinally effective separating devices, broken down into individual components, the hydrolysis mixture (8) being introduced into the feed part, methanol and unreacted methyl formate as the top product (5) and as a side product (10) are deducted, formic acid and carboxamide of the formula I as an extractant as an anhydrous or largely anhydrous sump product (9) is withdrawn, and -water (6) - preferably in liquid form - is removed from the withdrawal part, and c) the bottom product (9) of the 1st distillation column in a 2nd distillation column (3) in formic acid (11) and extracting agent (4) separates. |