Process for isolating acrylic acid from aqueous crude acid by extraction with an ester,water washing and azeotropic distillation of the washed extract
Abstract
Abstract ISOLATION OF PURE ACRYLIC ACID FROM AQUEOUS CRUDE ACID CONTAINING ACRYLIC ACID AND IN ADDITION SMALL PROPORTIONS OF ACETIC ACID AND POSSIBLY FORMALDEHYDE, BY ETHYL ACETATE EXTRACTION COMBINED WITH A SIMULTANEOUS WATER-WASH OF THE RESULTING ORGANIC EXTRACT AND DISTILLATIVE SEPARATION OF THE WASHED EXTRACT INTO (A) PURE ACRYLIC ACID AND (B) A READILY BOILING ETHYL ACETATE/WATER-AZEOTROPE COMPRISING EXTRACTING THE AQUEOUS ACRYLIC ACID-CONTAINING CRUDE ACID BY MEANS OF ABOUT 10 TO 15 PARTS BY WEIGHT ETHYL ACETATE, PER PART BY WEIGHT ACRYLIC ACID, AND SIMULTANEOUSLY WASHING THE RESULTING ORGANIC EXTRACT BY MEANS OF ABOUT 15 TO 25 PARTS OF WEIGHT WATER, PER PART BY WEIGHT ACRYLIC ACID.
Inventors
- 👤 Kurt Sennewald
- 👤 Klaus Gehrmann
- 👤 Heinz Handte
- 👤 Heinz Erpenbach
- 👤 Helmut Reis
Bibliographic Details
Claims Analysis
Total Claims: 0References Cited (Backward Citations)
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