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-----Effective Replacement of HCl as Pickling Bath
Q. HI,
I AM USING HCL ACID WITH TITRATION OF 18 WHEN NEWLY MADE AND DISPOSE WHEN TITRATION COMES TO 8. DIP TIME - 10 MINS
AS HCL IS VERY HAZARDOUS FOR THE ENVIRONMENT. I WANT TO KNOW IF THERE IS ANY PRACTICAL REPLACEMENT OF HCL AVAILABLE. IF YES, PLEASE PROVIDE ME WITH DETAILS.
THANK YOU FOR SUPPORTING.
- ODISHA, India
August 17, 2024
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A. Hi.
10 minutes sounds like an extraordinarily long pickle time for a plating shop. I don't understand the need for such extreme pickling.
Actually, HCl is the replacement for hot H2SO4 which was still quite popular when I started in the industry way back when, but which I haven't seen in use for decades now. So hot sulphuric acid is one possibility. I would suggest trying acetic acid in the lab if you must get rid of hydrochloric acid, although it would surprise me if it could replace 10 minutes in HCl 🙂
I don't think I agree that, if handled properly, HCl is hazardous for the environment. In theory the waste would be neutralized, the metal precipitated out, and only salt water would remain, which covers 2/3 of the earth.
Luck & Regards,
Ted Mooney, P.E. RET
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