after smb...

[big red 211]

My question is the one liner at the bottom of the my long winded explaination on how I butched my first attempt at this.

I am processing pins, fully and partially plated. I actually did two different batches that I've kept seperate due to me contaminating one batch. I started both out with AP in a crock pot. Then:
Batch 1 was pins that I spent tons of time on to eith pull of the circuit board sperately or cutting at the base with tin snips. After AP looked like it was done I poured it through a filter to get rid of the green acid. Next I seperated the pins from the gold... I don't actually remember how I did it. Maybe a strainer? Anyway, it was definately a mixture of different metals.

On Batch 2, this one turned out to be horrible. I simply cut around the connectors on the boards and through the whole thing in the crock pot. That left a mess with very little gold that had flaked off. So I got some lye and put everything in there for a while and scrubbed until I saw gold on most of the pins. I then cut the remaining circuit board off of the connectors and but the connectors back in some fresh AP. I let that sit in a crock pot till basically all the pins were completely dissolved. That got filtered out to get rid of the plastic connectors. The result was a ton of every metal in there. Which is what I was expecting. I figured at this point I just needed to get rid of the grey sludge and start over with just metal.

At this point I did both batches exactly the same. I rinsed them with straight hcl over 5 times and it was still turning green. I was pretty sure I wasn't doing it right so I decided to just desolve it and start over with whatever percipitates out of the solution. So, I desolved it in hcl +clorox. The result was a green colored solution, not the yellow color that Steve gets in his video. I then used SMB (actually Super Iron Out that Steve mentioned in another post, it's way cheaper) I never got the clear color until maybe 15 minutes after it was mixed together. It went from green to dark brown/black with SMB added. Then everything settled a day later and it's clear with the powder on the bottom.

Finally, here's my question. Is the powder at the bottom only gold? I ask because batch 2 had more metal in it but far less black powder after the SMB.

 

[Barren Realms 007]

It will probably be dirty and need to be sent thru your process again. Don't throw your solution away just yet. There might still be gold in this. Test your solution.


http://www.goldrefiningforum.com/phpBB3/viewtopic.php?f=49&t=6026

 

[butcher]

when you started you said you seperated pins from the gold, if you had pins left that is where alot of your gold will be.

if your solution is gold with alot of copper, you will most likely be better off adding a copper buss bar to the acidic solution, allowing the gold to cement out of solution. and do not forget about testing your solutions for values.

 

[big red 211]

The pins were showing the copper and maybe whatever is below the copper too. Would the gold still be on them somehow? I thought it was suppose to flake off of the pins when the acid desolves the copper?

 

[Barren Realms 007]

The pins were showing the copper and maybe whatever is below the copper too. Would the gold still be on them somehow? I thought it was suppose to flake off of the pins when the acid desolves the copper?

The copper dissolves and that is how the gold flakes off. But with it being on a crock pot there is always the possability that you might disolve some of the gold. Now it is supposed to drop to the bottom of your container as small black specks because of saturation of copper in the soution. But there is always the possability that your gold can replate onto the copper pins under the correct conditions. That is why it is important not to add too much peroxide if it is not needed. And to use a bubbler. It is also important that if you still had copper pins showing to finish running these thru your clean HCL till no more green discoloration shows in the HCL. The solution can also be blue if you are doing a lot of fiber CPU chips that contain iron in the pins.

 

[butcher]

If any gold is dissolved in solution, it will plate back onto any copper metal in solution.

HCl acid peroxide (even dilute peroxide), (even HCl and air in heat) can possibly dissolve some gold and heating and concentrating in a crock pot can increase this possibility

If none of gold ever dissolves then you might be able to separate most of the gold plate from copper pins.
But until all of the copper is dissolved leaving only gold and solution is tested , you will only be guessing how much gold is still with the remaining copper.