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Halt cyanide gold stripper action prior to plate out

I am trying to help a customer who would like to reverse plate gold out of a sodium cyanide strip solution.

Ray Conway
plating shop - Cranston, RI, USA
2005

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It's easy to do. You should used a smooth, preferably polished, and definitely passivated stainless steel cathode, which will allow the gold to be peeled off so it can be sold for high value reprocessing material. The anode can also be stainless steel. Operate at a low current density, say 2-3 amps/ft sq. It will take about one to three weeks to plate virtualy all the gold out. You can recover almost 100% of the gold by this method, and you should continue running until you get down to around 10 ppm. A side benefit is that the use of insoluble cathode will oxidize and destroy much of the cyanide, resulting in lower waste treatment cost.

Jeffrey Holmes, CEF
Spartanburg, South Carolina
2005