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Stainless steel 316 corrosion

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Sir,

We use ss 316 anodes to recover gold from dragouts of citrates and phosphates , where we put ss sheets of 5*20inchs one as anode and other as cathode we have electrolyzed the solution under acidic and alkaline media , we noticed that these ss316 anodes getting dissolved but not ss cathode by this dissolution my recovery efficiency has become very poor and un wanted contaminants getting deposited.we use only demineralized water no halogenic ions.platinised titanium anodes are costly and is not last longing . So advice why this problem and suggest what type of anode material to be used. Thanks,

BY USING GRAPHITE ANODES GRAPHITE ANODES LOSING ITS BOND STRENGTH IN TURN CARBON IS COMING INTO SOLUTION , BY PUTTING PP BAG IS ALSO IS NOT SERVING THE PURPOSE, AND I CANNOT AFFORD FOR FILTRATION IN THESE DRAGOUTS, AND EVEN I CANNOT GO FOR GOLD BUG. IS IT BECAUSE OF SIMILAR ANODE AND CATHODE MATERIAL OR IS IT ANY THING RELATED WITH ELECTRODE POTENTIALS.

Panjala Mukesh      fashion jewelry mfgr. Hyderabad, India

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I suspect that you are using too high a voltage when plating out the gold from your dragout tank. I try to keep the voltage between 4-5 Volts on my gold recovery unit. We have used the same 316 SS anodes for our gold bath for many years with almost no deteriation. We always transfer our dragout to a separate tratment tank for gold recovery. You should not have to adjust the dragout solution to be able to plate out the gold. If you need faster recovery you need more surface area, not more voltage. You should be able to get the gold down to about 75 mg/L or less. To recover the last bit of gold, pump the solution through some resin. Finally, I do not see the signifigance of impurities in the deposit, it needs to be refined anyway correct?

Joel Tomasetti
opticals - Petersburg, Virginia