Production of anhydrous or substantially anhydrous formic acid

US4262140A · kind A · utility

Assignee

• BASF SE

Inventors

• Kaspar Bott · Mannheim, DE
• Gerd Kaibel · Lampertheim, DE
• Herwig Hoffmann · Bischofswerda, DE
• Otto Kratzer · Frankenthal (Pfalz), DE
• Rudolf Irnich · Worms, DE

Key dates

• Filing date: Dec 3, 1979
• Grant date: Apr 14, 1981
• Expiry date: Dec 3, 1999

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C07C51/48
• WIPO field: Organic fine chemistry
• WIPO sector: Chemistry

Abstract

A process for the production of anhydrous or substantially anhydrous formic acid by hydrolysis of methyl formate which is carried out in a column having an upper fractionating section, a middle hydrolysis section and a lower extraction section and in which PA1 (a) the hydrolysis is carried out in the middle section of the columm, with water and methyl formate in countercurrent, PA1 (b) the resulting formic acid is extracted, in the lower section of the column, by means of a carboxylic acid amide which is fed into the lower end of the middle section of the column, PA1 (c) the extract phase, consisting in the main of formic acid and the carboxylic acid amide, is distillatively dehydrated, or substantially dehydrated, in the lower section of the column, PA1 (d) the methanol and uncovered methyl formate are removed by fractional distillation in the upper section of the column and PA1 (e) the pure formic acid or concentrated aqueous formic acid is distilled from the anhydrous or substantially anhydrous extract phase in a second column, leaving the carboxylic acid amide.