FIELD: chemistry.
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.
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.
19 cl, 12 ex
| Title | Year | Author | Number |
|---|---|---|---|
| 0 |
|
SU430550A1 | |
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|
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|
RU2366651C1 |
