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Plating Rhodium out of a Sulfuric Acid and Hydrochloric Acid Solution

I have some Rhodium tied-up in an acidic solution consisting of both sulfuric and hydrochloric acids. What volts and amps would I need plate the Rhodium out of this solution onto a stainless steel cathode just to recover it. Can I use a carbon anode to get the majority of it? There are also other metals in the solution. Thanks.

Dr. Brack Callahan
research - Kerrville, Texas
2007

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Since Rhodium is currently selling for nearly $6,000.00 per troy ounce, I can understand why you want to reclaim it. You didn't mention how much volume that you had or what the rhodium concentration is. If it is a relatively small volume, I would recommend shipping it to a refiner in the liquid form. For one thing,it is easily analysed when it is in the liquid form. Once you electrowin it, it will have to be assayed to determine the precious metal concentration, and some of it always seems to go missing.

Another option is to absorb it onto ion exchange resin and to send the resin to a refiner.

Lyle Kirman
consultant - Cleveland Heights, Ohio
2007

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Save yourself a lot of problems; send the solution to your refiner.
Don't forget to do an analysis first and let the refiner know that you have. It can save a lot of misunderstanding later!

Geoff Smith
Hampshire, England
2007