Process for isolating acrylic acid from an aqueous crude acrylic acid containing acetic acid by extraction and distillation with an entrainer-solvent
Abstract
Abstract PROCESS FOR ISOLATING PURE ACRYLIC ACID FROM AN AQUEOUS CRUDE ACID CONTAINING ACRYLIC ACID TOGETHER WITH SMALL PROPORTIONS OF ACETIC ACID, FORMALDEHYDE, ACROELIN, MALEIC ACID AND HIGHER CARBOXYLIC ACIDS AND POSSIBLY POLYMERIC ACRYLIC ACID, BY EXTRACTING THE CRUDE ACID USING AN ORGANIC SOLVENT, WATER-WASHING THE RESULTING ORGANIC EXTRACT, AND DISTILLING THE WASHED EXTRACT TO ISOLATE ACRYLIC ACID THEREFROM. THE AQUEOUS, ACRYLIC ACID-CONTAINING CRUDE ACID IS EXTRACTED USING 3,3,5-TRIMETHYLCYCLOHEXANONE AND/OR ISOPHORONE, THE RESULTING ORGANIC EXTRACT IS DEHYDRATED IN A FIRST DISTILLING ZONE AND BASE PRODUCT COMING FROM THE FIRST DISTILLING ZONE IS DISTILLED IN A SECOND DISTILLING ZONE TO OBATIN PURE ACRYLIC ACID.
Inventors
- 👤 Kurt Sennewald
- 👤 Klaus Gehrmann
- 👤 Heinz Handte
- 👤 Alfred Hauser
- 👤 Georg Kohl
Bibliographic Details
Claims Analysis
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