| abstract |
A method for preparing caprolactam, which is characterized in that in a two-phase reaction system composed of a B-L biacid deep eutectic solvent and an organic solvent, cyclohexanone oxime is used as a raw material to prepare caprolactam through rearrangement reaction, a deep eutectic solvent and a cyclic The molar ratio of hexanone oxime is 25:1 to 1:25, the organic solvent is 1 to 30 mL, and the reaction temperature is 40 to 120° C. for 2 to 8 hours to prepare caprolactam, and the deep eutectic solvent and the organic solvent are recovered and reused. The characteristics of the present invention are: the deep eutectic solvent-organic solvent two-phase system can realize high-yield and high-purity synthesis of caprolactam; the solubility difference between the deep eutectic solvent and the organic solvent for reactants and products is well avoided. The hydrolysis of the cyclohexanone oxime inhibits side reactions such as the oligomerization of the product caprolactam; the reaction conditions are mild, the product is easy to separate, the processing is simple, and the used deep eutectic solvent and organic solvent are easy to recover and reusable. |