Processes for preparing diaryl and/or alkylaryl carbonates from dialkyl carbonates

US8039659B2 · kind B2 · utility

Assignee

• Bayer MaterialScience AG · DE

Inventors

• Andre Düx · Bogen, DE
• Pieter Ooms · Krefeld, DE
• Johann Rechner · Krefeld, DE
• Matthias Böhm · Leverkusen, DE
• Kaspar Hallenberger · Leverkusen, DE
• Georg Ronge · Mülheim an der Ruhr, DE
• Johan Vanden Eynde · Zwijnaarde, BE

Key dates

• Filing date: Sep 15, 2008
• Grant date: Oct 18, 2011
• Expiry date: Aug 3, 2029

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C07C68/06
• WIPO field: Organic fine chemistry
• WIPO sector: Chemistry

Abstract

Processes comprising: reacting a dialkyl carbonate and an aromatic hydroxy compound in the presence of a transesterification catalyst in a first reaction column, the first reaction column comprising a top section, a bottom section, a rectifying section in an upper portion of the column and a reaction zone below the rectifying section; feeding a bottom product from the first reaction column to a further reaction column; the bottom product comprising a diaryl carbonate, an alkylaryl carbonate, or both, and residual unreacted dialkyl carbonate and aromatic hydroxy compound; the further reaction column comprising a top section, a rectifying section in an upper portion of the column and a reaction zone below the rectifying section; and reacting the residual unreacted dialkyl carbonate and aromatic hydroxy compound in the further reaction column; feeding a process stream to a distillation column, the process stream comprising a mixture of unreacted dialkyl carbonate and one or more reaction-product alcohols drawn from the first reaction column, the further reaction column, or both, such that the unreacted dialkyl carbonate is separated from the one or more reaction-product alcohols; and …