Patent · US Expired

Recovery of catalyst systems from diarylcarbonate-containing reaction mixtures by melt crystallization

US5824816A · kind A · utility

0Cited by

2References

9Claims

0Family size

Assignee

BAYER HEALTHCARE LLC · DE

Inventors

Hans-Josef Buysch · Krefeld, DE
Carsten Hesse · Krefeld, DE
Johann Rechner · Krefeld, DE
Hans-Peter Wirges · Krefeld, DE

Key dates

Filing date	Apr 1, 1997
Grant date	Oct 20, 1998
Priority date	—
Expiry date	Apr 1, 2017

Classification

Technology area (CPC Y)Emerging Cross-Sectional Technologies
CPC primaryY02P20/584
WIPO fieldOrganic fine chemistry
WIPO sectorChemistry

Abstract

Catalyst systems with a content of a platinum-group-metal catalyst, a co-catalyst, a quaternary salt and a base for the oxidative carbonylation of aromatic hydroxy compounds to the corresponding diaryl carbonates are obtained according to the invention as a residual melt by melt crystallization and can be returned into the carbonylation reaction or worked up to valuable materials. The melt crystallizate, which consists predominantly of diaryl carbonate and the parent aromatic hydroxy compound, is worked up to pure diaryl carbonate and pure hydroxy compound.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.