中科微点-全球专利检索

  1. Login
  2. Sign Up

Search Results

3 records (took 0.009 seconds)

    Production of caprolactam starting with cyclohexanone
    2.
    发明授权
    Production of caprolactam starting with cyclohexanone 失效
    生产使用环己酮的起始物起始

    公开(公告)号：US3562254A

    公开(公告)日：1971-02-09

    申请号：US3562254D

    申请日：1969-04-24

    Applicant: TECHNI CHEM CO THE

    Inventor： SHEEHAN DESMOND ,  VELLTURO ANTHONY F ,  GAY WALTER A ,  HEGARTY WILLIAM P ,  THRELKELD DONALD D

    IPC: C07D201/02 ,  C07D41/06

    CPC classification number: C07D201/02

    Abstract: A CONTINUOUS PROCESS FOR THE PRODUCTION OF CAPROLACTAM, INCLUDING ACETYLATION OF CYCLOHEXANONE WITH ACETIC ANHYDRIDE AND KETENE (WHICH REACTS WITH ACETIC ACID FORMED IN THE ACETYLATION REACTION). THE CYCLOHEXENYL ACETATE FORMED IS THEN NITRATED WITH CONCENTRATED NITRIC ACID AND THE RESULTING NITROCYCLOHEXANONE SEPARATED BY DISTILLATION. ACETIC ANHYDRIDE IS RECYCLED TO THE ACETYLATION REACTION, AND ACETIC ACID TOGETHER WITH MAKEUP ACETIC ACID IS PYROLYZED TO KETENE, WHICH IS ALSO USED IN THE ACETYLATION REACTION. THE NITROCYCLOHEXANONE IS THEN CLEAVED WITH AMMONIUM HYDROXIDE TO FORM THE AMMONIUM SALT OF 6-NITRO CAPROIC ACID, WHICH IS THEN REDUCED WITH HYDROGEN AND A HYDROGENATION CATALYST TO PRODUCE 6-AMINO CAPROIC ACID. THIS INTERMEDIATE IS THEN SEPARATED BY REMOVING AMMONIA, WHICH IS RECYCLED WITH MAKEUP AMMONIA TO THE CLEAVAGE REACTION. THE AQUEOUS 6-AMINO CAPROIC ACID IS THEN HEATED IN DILUTE AQUEOUS SOLUTION, 5% TO 25% W./V., TO CYCLIZE TO CAPROLACTAM. THE CAPROLACTAM IS THEN EXTRACTED WITH AN ORGANIC SOLVENT, SUCH AS TRICHLOROETHYLENE, AND THE UNCONVERTED AQUEOUS AMINO CAPROIC ACID RECYCLE TO THE CYCLIZATION STEP. SOLVENT IS THEN REMOVED AND THE CAPROLACTAM PURIFIED BY KNOWN MEANS. AN IMPORTANT PART OF THE PROCESS IS THAT THERE IS NO AMMONIUM SULFATE FORMED, WHICH IN EARLIER PROCESSES WAS AN UNDESIRABLE BY-PRODUCT. THE AMMONIA USED IN THE CLEAVAGE REACTION IS RECYCLED AND THERE IS NO LARGE LOSS OF RAW MATERIAL.

Patent Agency Ranking