| 摘要 |
A method is described for the production of purified caprolactam, comprising the steps: a) extraction with an organic extraction agent of raw caprolactam, obtained from the Beckmann rearrangement of cyclohexanone oxime, b) separation of the organic phase from step a), c) distillative separation of the organic extraction agent from the organic phase from step b), obtaining aqueous extract lactam, wherein, prior to distillative separation, an aqueous alkali hydroxide solution is added to a volume of 0 to 10 mmol/kg caprolactam, d) addition of 0 to 30 mmol alkali hydroxide/kg caprolactam to the aqueous extract lactam from step c), e) distillative dewatering of the aqueous extract lactam from step d) which has been mixed with alkali hydroxide, f) freeing the caprolactam from step e) of by-products with lower and higher boiling points than caprolactam by distillation, wherein at least 1.5 mmol alkali hydroxide/kg caprolactam is added in steps c) and d) combined. |
