摘要 |
In a process for the electrolytic pickling of chromium-containing stainless steel, pickling proceeds initially in an aqueous Na2SO4 solution and subsequently in acid, preferably mixed acid. The CrO42- formed is converted by the addition of reducing agent and acid as a function of the pH value and the redox potential to Cr2(SO3)3 or Cr2(SO4)3. H2SO4 serves as the acid and a substance is used as a reducing agent selected from the group Nax Hy Sz Ov, wherein x=0 to 2, y=0 to 2, y=1 to 6 and v=2 to 6. The pH value is adjusted to less than three by the addition of acid.
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