Method for making caprolactam from impure 6-aminocapronitrile
    2.
    发明授权
    Method for making caprolactam from impure 6-aminocapronitrile 失效
    从不纯的6-氨基己腈制备己内酰胺的方法

    公开(公告)号:US07390897B2

    公开(公告)日:2008-06-24

    申请号:US11083715

    申请日:2006-02-10

    IPC分类号: C07D201/08

    CPC分类号: C07D223/10

    摘要: The invention relates to the field of production of lactams from aminonitriles, and in particular to the production of ε-caprolactam by the vapor phase hydrolytic cyclization of 6-aminocapronitrile. A crude liquid caprolactam comprising ε-caprolactam (CL), 6-aminocapronitrile (ACN) and water obtained from a vapor phase cyclization reaction of ACN is contacted with hydrogen in the presence of a hydrogenation catalyst to convert the ACN in the crude liquid caprolactam to a product comprising hexamethylenediamine (HMD) and hexamethyleneimine (HMI). Tetrahydroazepine (THA) in the crude liquid caprolactam is converted to HMI during this hydrogenation. The HMD and HMI have lower boiling points compared to ACN and thus they are more easily separated from CL in the subsequent distillation operations. Thus a process to make CL from ACN with fewer distillation stages, and with lower pressure drop and lower base temperature, is accomplished.

    摘要翻译: 本发明涉及由氨基腈生产内酰胺的领域,特别涉及通过6-氨基己腈的气相水解环化生产ε-己内酰胺。 包含ε-己内酰胺(CL),6-氨基己腈(ACN)和由ACN的气相环化反应获得的水的粗液体己内酰胺在氢化催化剂存在下与氢气接触,将粗液体己内酰胺中的ACN转化为 包含六亚甲基二胺(HMD)和六亚甲基亚胺(HMI)的产品。 粗制液体己内酰胺中的四氢吖庚因(THA)在该氢化期间转化为HMI。 与ACN相比,HMD和HMI具有较低的沸点,因此在随后的蒸馏操作中它们更容易与CL分离。 因此,实现了具有较少蒸馏阶段以及较低压降和较低基础温度的来自ACN的CL的方法。