Cpu's

[goaldspektre]

I followed everyones advice on the forum and dissolved the base metals in a large lot of cpu's with nitric.I'm wondering if,for the refining step,anyone prefers AR to the HCL/Cl process as well as pro's and cons to each method?

 

[Anonymous]

At this point,all you need to do is add Hcl and you will have AR.You are not going to expell the remaining nitric without using it up,or incinerating.If it were me,I would just add the Hcl,warm it up,filter well,and precipitate.Make sure you check the solution with urea to see if you have any residual nitric,and if so,how much.

 

[philddreamer]

Mic, that would be, adding the HCl to the cpu's after decanting the nitric solution with the base metals, so that the remaining nitric in the cpu's & the added HCl will make AR?

Thanks!

Phil

 

[Anonymous]

(Face Palm!)
That hasn't happened in a while. Ummm yes make sure you decant the used nitric first!
Sorry about that.

 

[goaldspektre]

Is the nitric going to be "dirty" with base metals?If so should I re-refine the gold powder after dropping with smb,or will a good hcl wash be enough?Thanks guys for the response , I never thought of just adding hcl to the cpu's.

 

[philddreamer]

Mic, I know that you & I understand what you ment, but a newbe might had added the HCl to the "soup" ... :shock: :lol:

Thanks!

Phil

 

[Anonymous]

When you decant the used nitric,make sure and run it through a filter to catch any foils in the solution,the remaining residual nitric will work fine to dissolve the rest of the pins,and other gold,as long as you have removed all of the base metals.When you are done with everything just make sure you wash the powder well.You will be fine.

 

[goaldspektre]

Thanks guy's!

 

[philddreamer]

Goal, the nitric WILL be "dirty" with base metals, that's the reason for the nitric step. Decant the the dirty nitric solution, set aside for later recovery of silver & palladium, (if present).
To the cpu's, with some nitric left on them, (since the cpu's were not rinsed), add HCl, this like Mic suggested, will make AR. Heat the solution until all materials are dissolved; add a bit of nitric if needed to dissolve any remaining gold or Pt present. then continue with the proper steps. Hope this helps.

Mic, please add your 2 centavos!

Phil

 

[philddreamer]

Oooops... you already did! :lol:

 

[Anonymous]

Other than checking with urea for excess nitric,it's dead on.
Could you tell us,approximately how many pounds you are doing?

 

[goaldspektre]

30 lbs , 15# of which are pentiums with no lids and the rest are 486's.Any guesses on yield?