Copper pin seperation

[brintd09]

First rime recovering gold from computer parts

Used muriatic acid and hydrogen peroxide.

Worked well, but all the copper pins fell off of the processors.

I now have all my gold foils mixed with a bunch of copper pins.

Can i go ahead with refining with muriatic acid and bleach?

If so will only the gold precipitate out?

 

[speed]

No, the gold will cement out on the copper pins as fast as it dissolves. I would leave it all in the acid/peroxide until all the copper has dissolved, then try and dissolve gold. You may have to add fresh acid to your ap solution and bubble air through to keep the reaction going, expect it to take a fair while to dissolve all the copper..

 

[bigpagoda]

Dissolving pins in acid peroxide can take a long time- Mine took more than a week using multiple air bubblers and putting it out in a huge black crockpot in the summer sunshine. Occasionally stirring the solution helped also.

 

[jason_recliner]

A week! Luxury!
I have had copper (ii) chloride leach, aka acid peroxide / "AP" take 3 months, when I had a bubbler that had an open ended hose, before I discovered using a bubbling stone.

I now have all my gold foils mixed with a bunch of copper pins.

Brint, have you thrown everything in together? Do the processors still have the large metal heat spreader?

Since you have started this in CuCl2 leach, the best result will usually come from seeing that through to completion. But it will require patience; perhaps more than you anticipated.

If you want to throw us some numbers of how much acid and peroxide you've used, and the mass of the material, then we would be able to provide more specific advice. A photo wouldn't go astray too.

 

[brintd09]

After starting a new acid bath i believe i found my original problem. Some of the processors had steel pins which i think fouled up my solution.

The second time went great with an addition of an air stone to get better bubbling.

After it was all done i used a neodymium magnet to get any steel pins out of there.

I now have a nice pile of gold foils ready for the next step.

With the acid/bleach i can't find anything as far as a mix ratio? Also with heating it at the end im assuming that burns off whats left of the bleach so the gold will precipitate?

 

[g_axelsson]

Cover the gold and then some with HCl, then add bleach a little at a time. Bleach + HCl releases chlorine gas (toxic) and too much just bubbles away. If possible use a stir bar and a magnetic stirrer or swirl the acid and gold around so it dissolves easier. After 5-10 minutes add some more bleach until the gold is dissolved.

The bubbles you are seeing are chlorine gas going up in the air so do add as little as possible at a time. Best way is to continuously drip in the bleach slowly.

Yes, heating at the end or leaving it standing a day is to drive off any remaining chlorine that would redissolve gold as fast as you precipitate it.

Göran