Patent ID: 7384518
Filing Date: 2008-06-10
Classification: C07D,Y10S

Abstract:
1. A plant for the purification of lactams by distillation, comprising: three distillation columns mounted in series, the first being a dehydration column, the second column and the third column acting to separate either the compounds which are less volatile than the lactam as a bottom product of either the second or the third column, or the compounds which are more volatile, means for adding an acidic compound to the lactam before it is fed to the dehydration column, means for adding a basic compound to the lactam before it is fed to the third column, and means for withdrawing the purified lactam from the third column, and means for recovering the lactam present in the bottom product of either the second or third column containing compounds less volatile than the lactam, and for recycling recovered lactam for distillation.