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Zinc Recovery by Electrolysis

2005

Dear sir,

I want to extract zinc from zinc sulphate solution. Please clarify the following points.

1.What should be the specifications of Zinc sulphate solution? e.g., pH, Concentration etc.

2.What should the ANODE,CATHODE be made of?

3.What should the voltage be, 6v or 12v?

4.Should I add any chemical in the electrolyte to increase zinc recovery?

Early reply will be highly appreciated.

DILIP VARADE
Aditya Industries - Nshik, Maharashtra, India

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2005

Hi Dilip. Unfortunately you didn't gave us enough context--such as whether you have a single batch or a continuous waste stream, nor why you want to recover it. I realize that one reason to plate it out is to recover the value of the zinc, but what I mean is that it's easy to plate some zinc out, yet impossible to plate it all out, and exactly what to do depends on whether you are trying to reach levels suitable for discharge (at great expense) or levels where you get the best ROI, etc. Is it all to the better if additional contaminating metals plate out, or does that render the recovered metal less valuable and destroy the whole intent?
1. If you're actually trying to recover zinc, how is it that you are able to make up the solution to a desired pH and concentration?
2. Anodes can be high surface area reticulated carbon for best recovery or stainless steel for easiest separation.
3. Voltage should probably be less than 6V, with very close anode to cathode spacing.
4. If you are trying to purify an effluent you should not add any chemicals to it.

More details please.

Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey