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Reclaiming silver from our vacuum capacitors

Reclaiming Silver: My company products vacuum capacitors. Our finished produce is silver plated. Annually, we scrap 200-500 lbs of capacitors. I would love to find a away to recover the silver before scrapping the copper base. Does anyone have a solution for me?

Thanks,

Jeffery Watkins
- Cincinnati, Ohio
2003

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2003

Jeffery,

It doesn't sound like you have enough value to mess with. Typical silver plated copper scrap runs from 1%-2%. This would make your 200-500# of scrap be worth from $146 to $730, at a $5 silver market. It you didn't destroy the copper, it would be be worth about $120-$300. If your scrap is more valuable than this, or if you get 5,000#, let me know - it could change the whole deal.

There are 2 common ways of stripping silver from copper. The solutions used for these just happen to be 2 of the most dangerous concoctions ever made by man.

The first is NOT a silver recovery method, for anyone less than an expert. The reason I'm including it is that amateurs select it because it's formula is readily available. I'm sure injuries have occurred. It's main value is for re-plating of reject parts. It starts with a mix of 95% sulfuric acid and 5% nitric acid, by volume. Zero water. For regular silver thicknesses, it can be used at room temperature. For thicker deposits, you have to heat it, unless you want to wait forever. The Metal Finishing Guidebook says 180 deg.F. Man, I never had the guts to heat up more than a beaker full of this stuff. At room temp., it causes instant severe burns and one drop can cause blindness. When real hot, it will cook your flesh faster than a fire. Besides, what do you put it in? What do you do with the waste? On top of all this, it's extremely difficult and dangerous to get the silver out of the solution. DON'T-USE-THIS-SOLUTION!

The 2nd choice is about as bad. Cyanide. It doesn't even work very well, since it wants to eat the copper as bad as it wants to eat the silver. Then, you have to plate it out. Waste disposal is costly. Proprietary cyanide strippers are available, but it's very hard to recover the silver from them. There are ways, but not for beginners.

If this is strictly a silver/copper proposition, with maybe a little plastic, you might try directly selling it to a refiner that does circuit boards. He can easily slip it into his melts. A little extra copper makes the melt a little easier to do. If the capacitors contain liquids, he probably won't buy them, unless they are of high value. They tend to blow up in the melt. Don't have it refined. Just sell it to him as feed stock. He can assay it easy and know where he stands. A fair price for clean silver/copper only scrap, containing1-2% silver, from an electronics refiner, as feedstock, would be at least 50% of market values, across the board.

Regards,

Chris Owen
- Houston,Texas

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I read an article that stated using Fluoboric acid contain Titanium redux couple was successful in recovering tin, gold, silver from printed circuit boards, I can't find the article and was interested in knowing how to make this solution.?

Richard R. Conway
recovery of metal from printed circuit board scrap - Clearlak, California
2007

I come across a lot of silver plated items that are damaged and was wondering if there was any way to recycle the silver from them before I melt them down for the copper,

Brad Hoefer
Hobbyist - Deepwater, Missouri, USA
January 22, 2008

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I have several large 10 lb pieces. of aluminum that is silver plated approx. 100 lbs total. Is there a viable method for stripping this as I may acquire more of these later. thanks for your forum. rg

ronnie glenn
all around scrapper - tulsa Oklahoma
February 7, 2011

I recently separated 3 lbs of silver from copper electrical contacts. I took to a silver place today and after spectrographic analysis, they say that the silver solder has cadmium and makes it unsafe for them to process it. They returned it to me and could not tell me where to take it next. What do I do to sell this contaminated silver?

William Harden
- Miami, Florida, USA
March 6, 2012