Recovery of epsilon-caprolactone and alkane dicarboxylic acid by acid treatment and vacuum distillation
Abstract
Abstract THE RECOVERY OF EPSILON CAPROLACTONE AND OF ALKANE DICARBOXYLIC ACIDS FROM MIXTURES SUCH AS ARE OBTAINED IN THE INDIVIDUAL WASHING STEPS OF THE PROCESS FOR OXIDATION OF CYCLOHEXANE WITH AIR AT ELEVATED TEMPERATURE AND AT SUPERATMOSPHERIC PRESSURE AND CONTAINING SUBSTANTIALLY MONOCARBOXYLIC ACIDS, DICARBOXYLIC ACIDS AND EPSILON-HYDROXYCAPROIC ACID (IF DESIRED AFTER PART OF THE ADIPIC ACID PRESENT HAS BEEN SEPARATED) BY REMOVING WATER (IF PRESENT) AND THE MAJOR PORTION OF THE MONOCARBOXYLIC ACIDS (IF PRESENT) BY DISTILLATION, ADDING 1 TO 30% BY WEIGHT OF PHOSPHORIC ACID OR A COMPOUND FORMING THE SAME OR BORIC ACID, HEATING THE MIXTURE OBTAINED UNDER SUBATMOSPHERIC COMPONENTS, CONDENSING THE INDIVIDUAL FRACTIONS AND RECTIFYING AND/OR CRYSTALLIZING THE FRACTIONS. DISTILLATION TEMPERATURES ABOVE 150*C. ARE AVOIDED. EPSILON CAPROLACTONE IS USEFUL FOR THE PRODUCTION OF CAPROLACTAM, A STARTING MATERIAL FOR THE PRODUCTION OF FIBERS.
Inventors
- 👤 Anton Wegerich
- 👤 Otto-Alfred Grosskinsky
- 👤 Siegfried Winderl
- 👤 Gerhard Blum
Bibliographic Details
Claims Analysis
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