A/P precipitation

[golddigger2]

Hi I just did my first batch of A/P and got good results with the foils. see photo's. I believe that the best way to precipitate gold from A/P if to add copper untill the gold drops out of solution. I have placed a piece of plate copper in the solution and have an air bubbler keeping it moving. WIll this work to force the gold out of solution?

 

[Harold_V]

Yes, it will cause a recovery of gold, but the quality will be suspect. You can give the gold a hard boil in dilute nitric, but you risk dissolving some of the gold if you do. It's very difficult to rinse precipitated gold adequately to avoid some loss.

Your other option is to wash with HCl, which won't be a problem with dissolution of values unless you manage to get some nitrates mixed in with the recovered gold.

I would suggest you reserve the use of copper for recovering gold from batches that don't go well, and use a selective precipitant in its place. Copper will cement all values in solution, so in a sense, you aren't truly refining, although you are concentrating.

Explore the use of SMB (SO2) or ferrous sulfate for precipitation. Each of them do an adequate job.

Read Hoke.

Harold

 

[qst42know]

Please tell me thats a very fancy floor in your shop and you are not processing in your house. :!:

 

[golddigger2]

Thanks harold for all the advice. Am still reading hoke. No not refining in my house, i just moved stuff inside for photo's as it was easier to light indoors. I then took them back out to the shop.

 

[glorycloud]

I assume that you are wanting to force the gold out of your AP solution.
The AP solution is reusable amigo. I wasted a whole bunch before I saw here
on the forum that it can be used over and over until it is saturated .
The color of the saturated solution is a very dark brown color. That's when you
may want to go after the gold that may have been dissolved in your AP solution. 8)

 

[gold4mike]

If you do as Glory Cloud says and reuse the solution, The copper that is dissolving from the next batch of fingers will cement out any gold that may have been in your solution. No need to add copper - that would just speed up the saturation of your solution and force you to make a new batch sooner.

 

[qst42know]

Just be safe. 8)

Fumes from refining chemicals make Chinese drywall seem like gingerbread :twisted:

 

[golddigger2]

thanks for the advice everybody. That makes it easy i will just keep using it untill it is saturated. To reuse with a new batch of fingers do you need to add more HCL or peroxide?

 

[LeftyTheBandit]

Peroxide to start off then use a fish tank bubbler to keep the O2 and for agitation.

The HCl should be ok as is.

 

[Palladium]

http://goldrefiningforum.com/phpBB3/download/file.php?id=3021