A dual-cascade system for the purification of regenerated uranium hexafluoride from U-232,(234,)236 is proposed. In the first cascade, regenerated uranium is enriched to a U-235 concentration of no less than 20% with a decrease in the mass U-236/U-235 ratio. Its additional feed flow is waste uranium hexafluoride, whose contaminated flow is removed as an additional product. The second additional feed flow is natural uranium hexafluoride. The main product flow from the first cascade is sent as a feed flow to the second cascade. Its waste purified from U-232,(234) is diluted with low-enriched or natural uranium hexafluoride to the U-235 concentration less than 5%. A numerical experiment is also performed. It is shown that the product formed after diluting the waste of the second cascade satisfies the ASTM C996-20 specification requirements for enriched commercial uranium hexafluoride in terms of U-232,(234,)236.