Preparation of formic acid

US5206433A · kind A · utility

Assignee

• BASF SE

Inventors

• Heinz Hohenschutz · Mannheim, DE
• Johannes E. Schmidt · Ludwigshafen, DE
• Hans Kiefer · Leopoldshafen, DE

Key dates

• Filing date: May 9, 1985
• Grant date: Apr 27, 1993
• Expiry date: May 9, 2005

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C07C51/09
• WIPO field: Organic fine chemistry
• WIPO sector: Chemistry

Abstract

Anhydrous or substantially anhydrous formic acid is prepared by hydrolyzing methyl formate in the presence of a formamide and then obtaining the formic acid from the hydrolysis mixture by distillation, by a method in which the hydrolysis is carried out in the presence of 0.5-3 moles, per mole of methyl formate, of a water-soluble formamide of the general formula I ##STR1## where R.sup.1 and R.sup.2 are each alkyl or together form an alkylene group, giving a 5-membered to 7-membered ring, with the proviso that the sum of the carbon atoms in R.sup.1 and R.sup.2 is 5 or 6 and, in the case of an alkylene group, a carbon atom which is not directly bonded to the N atom can be replaced by an oxygen atom.