| abstract |
The invention relates to a method for the distillative separation of ammonia and water from mixtures arising during the production of polyamides, said mixture containing a lactam and/or diamines and, optionally, an aminonitrile and/or dinitrile in addition to cyclopentanones as foreign substances. Said method consists of two steps: 1) the mixture is distilled at 11 - 35 bars, resulting in the production of water, ammonia and cyclopentanone as overhead products (K1), and water, lactam and/or diamines and, optionally, aminonitrile and/or dinitrile, as base products (S1), and 2) K1 is distilled at 11 - 35 bars, resulting in the production of ammonia and cyclopentanone as an overhead product, and water as a base product (S2). |