FIELD: organic chemistry, chemical technology. SUBSTANCE: invention relates to method for purification of lactam prepared from aminoalkylnitrile, in particular, ε-caprolactam. Cyclization medium is subjected for hydrogenation, removing volatile compounds and indicated medium is treated using ion-exchange resin or by distillation with sulfuric acid and lactam is recuperated by crystallization. Solvent for crystallization is taken among group including lactam, lactam aqueous solution, water, saturated hydrocarbons, aromatic hydrocarbons, organic halogenated compounds, ketones. In particular, lactam aqueous solution is used as a solvent. Mass concentration of lactam in solution for crystallization is above 80 wt.-%. Invention provides achievement of high purification degree of lactam from impurity of volatile bases in their concentration below 0.04 mg-equiv./kg. EFFECT: improved purification method. 8 cl, 2 tbl, 2 ex
| Title | Year | Author | Number |
|---|---|---|---|
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