The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Oct. 18, 2011
Filed:
Sep. 15, 2008
Andre Düx, Brühl, DE;
Pieter Ooms, Krefeld, DE;
Johann Rechner, Kempen, DE;
Matthias Böhm, Leverkusen, DE;
Kaspar Hallenberger, Leverkusen, DE;
Georg Ronge, Düsseldorf, DE;
Johan Vanden Eynde, Zwijnaarde, BE;
Andre Düx, Brühl, DE;
Pieter Ooms, Krefeld, DE;
Johann Rechner, Kempen, DE;
Matthias Böhm, Leverkusen, DE;
Kaspar Hallenberger, Leverkusen, DE;
Georg Ronge, Düsseldorf, DE;
Johan Vanden Eynde, Zwijnaarde, BE;
Bayer MaterialScience AG, Leverkusen, DE;
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 recycling the separated, unreacted dialkyl carbonate to the first reaction column; wherein the further reaction column comprises one or more condensers, and heat of condensation from the one or more condensers is fed back into the process.