公开(公告)号：US3879380A

公开(公告)日：1975-04-22

申请号：US31363872

申请日：1972-12-11

Applicant: STAMICARBON

Inventor： DE ROOIJ ABRAHAM H ,  GOETTSCH REIJER

IPC: B01D11/04 ,  B01D9/02 ,  C07D201/04 ,  C07D201/16 ,  C07D41/06

CPC classification number: C07D201/16 ,  C07D201/04

Abstract: A process for recovering lactams from a mixture of one or more lactams and sulphuric acid is disclosed, wherein the sulphuric acid is neutralized with ammonia or an ammonium salt to ammonium hydrogen sulfate in the presence of a lactam solvent. The neutralization produces a melt of ammonium hydrogen sulfate and a solution of lactam in the organic solvent, and the melt is readily separated from the solution. The lactam can then be recovered from the organic solvent. The process allows the lactam to be recovered in good yield without producing, as by-product, ammonium sulfate.

Abstract translation: 公开了一种从一种或多种内酰胺和硫酸的混合物中回收内酰胺的方法，其中硫酸在内酰胺溶剂存在下用氨或铵盐中和至硫酸氢铵。 中和产生硫酸氢铵的熔体和内酰胺在有机溶剂中的溶液，并且熔体容易从溶液中分离出来。 然后可以从有机溶剂中回收内酰胺。

公开(公告)号：US3859278A

公开(公告)日：1975-01-07

申请号：US38474773

申请日：1973-08-01

Applicant: STAMICARBON

Inventor： DE ROOY ABRAHAM H ,  GOETTSCH REIJER

IPC: C07D201/16 ,  C07D41/06

CPC classification number: C07D201/16

Abstract: Lactams are recovered from a solution of one or more lactams and sulfuric acid in an organic solvent after neutralization with ammonia or an ammonium salt and water without the simultaneous coproduction of solid ammonium sulfate according to the disclosed process. Ammonium hydrogen sulfate produced in the neutralization step is removed in the solution form, preferably concentrated to about 80 per cent by weight and the lactam is recovered from the organic solvent. Removing the ammonium hydrogen sulfate in the solution form rather than a solid avoids crystallization and deposition of the salt onto the surfaces of processing equipment.