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Dephosphating formula (for zinc phosphating)

2006

HI
please answer to me about DE-PHOSPHATING component (formula) for zinc phosphating .

thank you very much.

MOHAMAD SOLTAN REZAEI
- ESFAHAN, IRAN

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You can strip the phosphate coating using the following:

Concentrated hydrochloric acid containing 20 g/l of antimony trioxide.

This solution will effectively remove the phosphate coating in a short duration with minimal attack on the base metal.

T.S.N. Sankara Narayanan
- Chennai, Tamilnadu, India
(ed.note Nov. 2017: The good doctor has a fascinating blog at https://advancementinscience.wordpress.com)
2006

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2006

HI

please answer to me about alkaline remove ZINC PHOSPHATING component (formula).

I used of NAOH but the iron surface is the black .please help me to de-phosphating of iron.

thank you very much.

John
- Barselona

Mixing 144g of ammonium dichromate crystals to a gallon of ammonium hydroxide works as a good stripping solution for zinc phosphate. Leave the part in the solution for a few minutes.

Ronald Zeeman
coil coating - Brampton, ON, Canada
2006

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HI SIR
I do test with ammonium dichromate and ammonium hydroxide for de-phosphating but not remove zinc phosphating.
I need to alkaline stripping for cleaned iron of zinc phosphating . please help to me component for alkaline remover for zinc phosphating .
thank you very much.

Mohammad
- Iran
2006