Process for preparing diaryl carbonates from dialkyl carbonates

US8304509B2 · kind B2 · utility

Assignee

• Bayer Intellectual Property GmbH · DE

Inventors

• Christoph Gürtler · Cologne, DE
• Thomas Ernst Müller · Aachen, DE
• Pieter Ooms · Krefeld, DE
• Friedhelm Risse · Hanerau-Hademarschen, DE
• Johann Rechner · Krefeld, DE
• Franco Doro · Aachen, DE
• Angelina Prokofieva · Aachen, DE

Key dates

• Filing date: Oct 3, 2011
• Grant date: Nov 6, 2012
• Expiry date: Oct 3, 2031

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C08G64/307
• WIPO field: Organic fine chemistry
• WIPO sector: Chemistry

Abstract

The present invention relates to a process for continuously preparing diaryl carbonates from dialkyl carbonates and at least one monohydroxyl compound in the presence of catalysts, and to the use thereof for preparation of polycarbonates. The alkylene glycol obtained in the preparation of the dialkyl carbonate used is recycled by oxidative carbonylation with carbon monoxide in the presence of a catalyst to give the cyclic alkylene carbonate which is in turn converted to the dialkyl carbonate. More particularly, the process utilizes the alkylene glycol obtained for the diphenyl carbonate preparation process (DPC process).