Removal of catalyst residue from polyphenylene ethers
Abstract
Abstract THIS INVENTION RELATES TO SEPARATION AND RECOVERY OF COPPER-AMINE COMPLEX CATALYST RESIDEUS FROM A REACTION STREAM IN A PROCESS FOR THE FORMATION OF POLYPHENYLENE ETHERS BY AN OXIDATIVE COUPLING POLYMERIZATION REACTION. THE PROCESS COMPRISES SIMULTANEOUSLY TERMINATING THE REACTION AND EXTRACTING CATALYST RESIDUE BY CONTACT OF THE REACTION SOLUTION WITH AN AQUEOUS ACID SOLUTION IN A COUNTERCURRETN, LIQUID-LIQUID EXTRACTION COLUMN. THE POLYMER IS THEN RECOVERED FROM THE REACTION SOLUTION SUBSTANTIALLY FREE OF CATALYST RESIDUE. THE AMINE IS RECOVERED FROM THE AQUEOUS ACID SOLUTION BY PH ADJUSTMENT WITH ALKALI AND MAY BE RE-USED IF DESIRED. THE PROCESS OF THE INVENTION IS LESS EXPENSIVE THAN PRIOR ART PROCEDURES AND PROVIDES MORE EFFECTIVE CATALYST REMOVAL THAN OEHRE COMMERCIALLY ACCEPTABLE METHODS.
Inventors
- 👤 Michael M Modan
Bibliographic Details
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