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Ammonium Bi-fluoride or HFA?

My company is currently studying the feasibility of implementing a pickling line for stainless steel. I realize the Nitric Acid/HFA solution is very dangerous and would like to know the pros and cons of using ABF in place of HFA. Can we expect the same results?

Eric Buchanan
- Springfield, Missouri
2002

1) I think the nitric/ABF is just as effective. About 1.1-1.2 oz/gal of ABF is equivalent to 1 vol.% HF (49 wt%).

2) The solution is still dangerous; just the HF vapor is eliminated.

3) ABF makes the wastewater treatment more difficult; the ammonium ion is a chelating agent for heavy metals.

Ken Vlach [deceased]
- Goleta, California
Finishing.com honored Ken for his countless carefully researched responses. He passed away May 14, 2015.
Rest in peace, Ken. Thank you for your hard work which the finishing world, and we at finishing.com, continue to benefit from.
2002

Dear sirs,

We are also using same formulation for pickling and cleaning welding scales at the bends and corners but some times liquid drips out and creates problems . Please guide me with right thickening agent for the same. I have tried 1 proprietary thickening agent from one supplier but it is inhibiting the process. Hope to hear soon.

Regards,

Qutub Saify
chemical supplier - U.A.E.
2003