EP0509275A1
Expired / Lapsed
EP
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Process for the purification of indigo
Assignee: BASF SE
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Filing: 1992-03-24
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Granted: —
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Expires: 2012-03-24
Abstract
Abstract Translated from German Die Erfindung betrifft ein Verfahren zur Herstellung von gereinigtem Indigo, das dadurch gekennzeichnet ist, daß die bei der Synthese anfallende wäßrig alkalische Indoxylatlösung vor ihrer Oxidation zu Indigo unter Sauerstoffausschluß mit einem inerten wasserunlöslichen Lösemittel extrahiert wird. The invention relates to a process for the preparation of purified indigo, which is characterized in that the aqueous alkaline indoxylate solution obtained in the synthesis is extracted with an inert water-insoluble solvent with the exclusion of oxygen before it is oxidized to indigo.
Inventors
- 👤 Reinhold Dr. Kohlhaupt
- 👤 Manfred Dr. Gaeng
- 👤 Walter Bieg
- 👤 Matthias Dr. Fankhaenel
- 👤 Lothar Haas
- 👤 Guenter Dr. Engelhardt
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-03 19:32
CPC Classifications
C; C07; C07D; C07D209/00; C07D209/02; C07D209/04; C07D209/30; C07D209/32; C07D209/36; C09; C09B; C09B7/00; C09B7/02
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