Method for Separating Ammonia and Water From Mixtures, Arising During The Production of Polyamides

• Main Authors: DEININGER JURGEN, SOTJE OLIVER, LONING JAN-MARTIN, KORY GAD, ASSMANN JENS, DEMETER JURGEN
• Format: Patent
• Language: English
• Published: 18.10.2007
• Subjects: AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F,C08G; AMMONIA; CHEMISTRY; CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO WASTEWATERTREATMENT OR WASTE MANAGEMENT; COMPOSITIONS BASED THEREON; COMPOUNDS THEREOF; CYANOGEN; GENERAL PROCESSES OF COMPOUNDING; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; INORGANIC CHEMISTRY; MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONSONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS; METALLURGY; ORGANIC MACROMOLECULAR COMPOUNDS; PERFORMING OPERATIONS; PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL; SEPARATION; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS; TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINSTCLIMATE CHANGE; THEIR PREPARATION OR CHEMICAL WORKING-UP; TRANSPORTING; TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE; WORKING-UP

In a process for distillatively removing ammonia and water from mixtures obtained in the preparation of polyamides which comprise a lactam and/or diamines, and, if appropriate, an aminonitrile and/or dinitrile, and also a cyclopentanone impurity in two stages: 1) the mixture is distilled at from 11 to 35 bar to give, as the top product T1, water, ammonia and cyclopentanone, and, as the bottoms B1, water, the lactam and/or diamines, and, if appropriate, the aminonitrile and/or dinitrile, and 2) T1 is distilled at from 11 to 35 bar to give, as the top product T2, ammonia and cyclopentanone, and, as the bottoms B2, water.