Method for preparing caprolactam from cyclohexanone oxime

• Main Authors: LIU DANHE, YANG CHUNHE, LI ZHI, YU ANPING, REN XIAOHANG, HAN HAIBO, LI JINGJING, ZHANG GUOLIANG, SHEN FANGXIA, LI XIN, WEI XIAOBO, LIU LINJIAO
• Format: Patent
• Language: Chinese; English
• Published: 16.07.2021
• Subjects: CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOIDCHEMISTRY; CHEMISTRY; HETEROCYCLIC COMPOUNDS; METALLURGY; ORGANIC CHEMISTRY; PERFORMING OPERATIONS; PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL; THEIR RELEVANT APPARATUS; TRANSPORTING

The invention discloses a method for preparing caprolactam from cyclohexanone-oxime. According to the method, the existing cyclohexanone-oxime solution with the concentration of 20% or below is replaced with a cyclohexanone-oxime solution with the concentration of 20.5-80% to react with high-concentration fuming sulfuric acid, and the high-concentration fuming sulfuric acid is added at one time; the high-concentration cyclohexanone-oxime solution is added into a series-connected microreactor group in a multi-section step-by-step manner for a rearrangement reaction, so that cyclohexanone-oxime is rearranged to prepare caprolactam, and meanwhile, the reaction temperature is well controlled due to the adoption of a microreactor technology in the reaction process, so that the product quality is improved, and the production efficiency is improved. 本发明公开了一种由环己酮肟制备己内酰胺的方法，该方法提出：采用浓度为20.5-80％环己酮肟溶液代替现有浓度为20％以下环己酮肟溶液和高浓度的发烟硫酸进行反应，且将高浓度发烟硫酸一次加入，使用高浓度环己酮肟溶液多段分步加入串联的微反应器组中进行重排反应，使环己酮肟重排制备己内酰胺，同时由于反应过程中采用微反应器技术使得反应温度得到很好的