公开(公告)号：CZ288217B6

公开(公告)日：2001-05-16

申请号：CZ197297

申请日：1995-12-22

Applicant: BASF AG

Inventor： RITZ JOSEF DR ,  FISCHER ROLF DR ,  SCHNURR WERNER DR ,  ACHHAMMER GUENTER DR ,  LUYKEN HERMANN DR ,  FUCHS EBERHARD DR

IPC: C07D201/08 ,  C07B63/02 ,  C07D201/16

Abstract: The invented continuous purification process of raw caprolactam by hydrogenation followed by subsequent treatment in acid environment and then by distillation in alkaline medium is characterized by (a) converting 6-aminocapronitrile by reaction thereof with water to raw caprolactam, (b) separating high- and low-boiling components from the raw caprolactam of the stage (a), (c) treating the raw caprolactam obtained in the stage (b) with hydrogen at a temperature ranging from 50 to 150 degC and pressure in the range of 0.15 to 2.5 MPa in the presence of a hydrogenation catalyst and a required solvent and so obtaining a mixture A, (d1) conducting the mixture A in the solvent and at a temperature ranging from 30 to 80 degC and pressure in the range of 0.1 to 0.5 MPa through an ion exchanger containing acid terminal groups and to thereby obtaining a mixture B1 or (d2) distilling the mixture A in the presence of sulfuric acid, whereby prior addition of sulfuric acid the solvent being present can be removed and to thereby obtaining a mixture B2 and (e) distilling the mixture B1 or the mixture B2 in the presence of a base to thereby obtaining raw caprolactam.