| abstract |
FIELD: chemistry. n SUBSTANCE: invention relates to an improved method of purifying crude ε-caprolactam obtained from cyclohexanone oxime via gas phase Beckmann rearrangement, comprising a step for crystallisation of ε-caprolactam from the solution of crude ε-caprolactam in ether or halogenated hydrocarbon, a step for washing the crystalline ε-caprolactam obtained from the crystallisation step with a solvent and a step for hydrogenation of the crystalline ε-caprolactam through contact with hydrogen in the presence of a hydrogenation catalyst. n EFFECT: high purity of the product, high absorption of potassium permanganate and extraction coefficient at wavelength 290 nm equal to or less than 0,05, which meets all requirements for commercial products. n 19 cl, 12 ex |