Processing Fingers with AP Question

[kadriver]

I have the DVD that demonstrates processing trimmed escrap fingers with AP.

I have about 2 1/2 lbs of clean fingers that I am going to process

In the DVD, the gold foils are removed from the cards by leaching in HCl and H2O2.

Some gold appears to dissolve in the solution as the golf foils are being leached.

The dissolved gold from this step is not addressed in the DVD (or I may have missed it).

What is the process for getting the gold from this solution?

Do I just filter the solution and drop with SMB?

Also, can I use a higher percentage of H2O2 (such as 12% instead of 3%) to get the reaction to move faster?

Thanks - kadriver

 

[philddreamer]

Kad, as the AP saturates with copper, any gold dissolved will cement.

Adding too much peroxide at once is the reason why some of the gold dissolves. Yes, you can use the 12%, but add the peroxide in increments so only the copper, & other BM's dissolve & not the gold. You can use a bubbler, after the first addition of peroxide, & save on peroxide.

Phil

 

[Geo]

i agree. as soon as the copper is expose, the gold will cement back out so dont discard or overlook any powdered solids after the process is completed.

 

[kadriver]

The dissolved gold will cement to copper producing black powder.

No need to drop with SMB as the gold will already be out of the solution from the copper.

Thanks - kadriver

 

[radical351]

just a question here. all you have to do is just had a copper piece and the gold is cemented out. like silver to nitric?

 

[philddreamer]

Yes, that's correct.
In Ap, you will be digesting a lot of copper, say, from fingers, so you may not have to add any copper. (Also, the gold will only dissolve if you add too much peroxide.)

Phil

 

[radical351]

thank you very much