Production of acetic anhydride

US4430273A · kind A · utility

Assignee

• Hoechst GmbH · DE

Inventors

• Heinz Erpenbach · Cologne, DE
• Klaus Gehrmann · Lechenich, DE
• Hans-Klaus Kubbeler · Rheinbach, DE
• Klaus Schmitt · Wiesbaden, DE

Key dates

• Filing date: Apr 7, 1982
• Grant date: Feb 7, 1984
• Expiry date: Apr 7, 2002

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C07C51/56
• WIPO field: Organic fine chemistry
• WIPO sector: Chemistry

Abstract

The invention provides a process for making acetic anhydride, wherein methyl acetate and/or dimethylether is (are) reacted with carbon monoxide under substantially anhydrous conditions, at temperatures of 350 to 575 K and under pressures of 1 to 300 bars in the presence of a catalyst system comprised of noble metals belonging to group VIII of the periodic system of the elements, or their compounds and iodine and/or its compounds. More specifically, an aliphatic carboxylic acid with 1 to 8 carbon atoms and at least one heterocyclic aromatic compound, in which at least one hetero atom is a quaternary nitrogen atom are used as promoters.