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Separating copper from nickel by electrolysis

I would like to separate copper from nickel by electrolysis using platinum plates. My question is, can I electroplate copper first.

Dragoljub Lukic
student - Geneva, CH
June 24, 2008

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Hi, Dragoljub. Electroplating shops routinely purify their nickel solution by "dummying out" the copper at low voltage. In principle electrolysis can be used, but how best to do it depends on your actual circumstance (volumes, ratio of nickel and copper in solution, what you will do with the copper, what you will do with the nickel, what other metals are present, what acid they are dissolved in, etc., etc.)

For example, the electroplating shop doesn't care if there is a little bit of nickel plated out in the dummied copper, but you might.

Regards,

Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
June 24, 2008

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They will plate out as an alloy, but the voltage will determine the alloy. To plate nearly pure copper, you will need to plate at around 1 amp per square foot of cathode, which will be horribly slow. A problem that will go with it is the use of insoluble anodes will lower the pH enough so that the solution will quit plating. The addition of lye to raise the pH will precipitate some of both metals unless it is added in a dilute solution and this will dilute your chemicals to a point that they will not want to plate out normally.
You may find something that will work, but expect a LOT of trial and error.

James Watts
- Navarre, Florida
June 25, 2008