Chemistry: electrical and wave energy – Processes and products – Electrostatic field or electrical discharge
Patent
1988-05-03
1989-07-25
Tufariello, T. M.
Chemistry: electrical and wave energy
Processes and products
Electrostatic field or electrical discharge
C25F 106
Patent
active
048510920
ABSTRACT:
In a process for the electrolytic pickling of chromium-containing stainless steel, pickling proceeds initially in an aqueous Na.sub.2 SO.sub.4 solution and subsequently in acid, preferably mixed acid. The CrO.sub.4.sup.2- formed is converted by the addition of reducing agent and acid as a function of the pH value and the redox potential to Cr.sub.2 (SO.sub.3).sub.3 or Cr.sub.2 (SO.sub.4).sub.3. H.sub.2 SO.sub.4 serves as the acid and a substance is used as a reducing agent selected from the group Na.sub.x H.sub.y S.sub.z O.sub.v, 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.
REFERENCES:
patent: 3025225 (1962-03-01), Snyder
patent: 4363709 (1982-12-01), Zaremski
patent: 4415415 (1983-11-01), Zaremski
"Electrolytic Descaling of 18Cr-8Ni Steel in Sodium Sulfate Solution", by Y. Furutani et al., Chem. Abstracts, vol. 87, #14, 1977, p. 396, #108322s.
"Metal Cleaning", by M. Yamamoto, Chem. Abstracts, vol. 104, No. 22, 1986, p. 271, #190761k.
Japanese Patents Gazette, Section CH: Chemical, Week 8602, 1986, Derwent Publications Ltd., London.
Maschinenfabrik Andritz Actiengesellschaft
Tufariello T. M.
LandOfFree
Process for electrolytically pickling chromium-containing stainl does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Process for electrolytically pickling chromium-containing stainl, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Process for electrolytically pickling chromium-containing stainl will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2356083