The paper considers features of enriched regenerated uranium hexafluoride purification from 232, 234, 236U in a double cascade with a supply of uranium hexafluoride wastes for the additional feeding of the first cascade. The effective purification from 236U is carried out in the first cascade at a 235U concentration of less than 20% in long cascades with a large number of stages. The parameters of the second cascade, fed by the product of the first one, which significantly reduce the concentration of 232, 234U in the wastes, were determined. Its reduction with uranium hexafluoride wastes ensures the compliance with the requirements of the ASTM C996-20 specification, established for enriched industrial uranium hexafluoride.