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Pine Beach, NJ

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Silver Reclaim from Nitric-Sulfuric Strip

Q. I have about 50 gallons of a conventional 19:1 part sulfuric:nitric acid strip which we've used to remove silver plating from copper. In order to recover the silver, I've contacted several previous metal recovery firms all of whom won't handle it unless it's either solid or, if liquid, cyanide. Any suggestions on how I can treat in house or through a recovery firm?

Milt Stevenson
Owner - Syracuse, New York, USA
May 22, 2012

May 30, 2012

A. Add it, slowly and with appropriate caution, to about twice the volume of water. Then, add NaCl to drop the Ag as AgCl. Allow to settle, decant waste acid off, trickle it into your wastewater treatment system.

Take the solids, add baking soda [in bulk on eBay or Amazon [affil links] to neutrality, then dry. This should now be a stable silver rich solid that need not be shipped as a corrosive.

Dave Wichern
Consultant - The Bronx, New York

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