CPU collection lot 2

[gold4mike]

Goldenchild is exactly right when he says to add nitric acid literally by the drop.

You will be amazed at how little nitric it takes when you are dissolving foils.

Early on in my education here I learned of and started using Harold's method of putting a small button of gold in my beaker to use up excess nitric. When I first started doing that I found I was dissolving as much as 1/2 gram of gold to kill the nitric.

I switched to using an eyedropper to add nitric, and using medium heat on my hotplate. If all activity stops and you have just a bit of gold left to dissolve, add one drop and wait a few minutes. Repeat this process until your gold is dissolved and you won't have any problem getting it to precipitate.

Using the proper amount of nitric is much better and less time consuming than trying to kill the excess.

 

[kjavanb123]

All,

My problem now is the dark green solution left that shows no sign of gold anymore after addition of copperas.

No sings of brown powder, is there anything to recover the gold...?

Regards
Kevin

 

[samuel-a]

Kev

Do you have SMB ?

 

[kjavanb123]

Samuel

Yes, should I use smb?

Regards
Kevin

 

[Barren Realms 007]

Samuel

Yes, should I use smb?

Regards
Kevin

If it is your 1st recovery and there are a lot of base metals involved I would ues copperas. If it is the 2nd refining and your material is fairly clean I would use SMB.

 

[kjavanb123]

Some updates on this project, after processing 2 IBM ceramic CPUs and 4 VIA CPUs all gold lid, in AR with minimal amount of nitric, and produced 0.46 grams of purified of gold powder. So this is 0.46 / 6 = 0.076 grams of pure gold powder in each of these CPUs. Is this normal?

Also, I. Processed the remaining INtel CPUs got 0.92 grams of pure gold.


Thanks
Kevin