Ar process

[gavahooa]

Hi, I have been trying to recover gold from a few old computer parts i have. Ihave no problems with the aqua regia part, its the part after that im having trouble with. Can anybody help me out with this please?????

 

[philddreamer]

Hi Gavahooa!
What type of computer parts?
How much computer parts?
Did you de-base the material before AR?
What part of the "after AR" part are you refering to?
Did you read and search ALL the information needed before starting the process?

Kindly,
Phil

 

[publius]

Let us know what steps you have taken to reach the AR process.

 

[gavahooa]

I have loads of ram chips and other boards with gold fingers on. I have removed the gold strips from the board and i am putting them into aqua regia. This part i guess is right because there is no gold left on the strips when its finished.
Its the precipitating of the gold i carnt get right.
Any tips would be very gratfull

 

[philddreamer]

Gava, the best process for fingers is AP. AP will get rid of the base metal, (copper), and leaves you with gold foils. These then you dissolve in HCl/Cl and the precipitation should be much easier.
Running them thru AR will create problems, as you just found out. Yes, the AR dissolved ALL the gold, BUT also ALL the copper!
Chances are, that you still have free nitric in your solution and that's why no precipitation. You need to get rid of the nitric by evaporation, or neutralize with a bit of urea.

Take care and be safe!
Phil

 

[wade brenckle]

I did the same thing. with a lot of stuff. I am about to evaporate for the 4th time. I will in the next day or so try the ap method with with pins fingers, and rich looking phone innerds. Any advice before I embark ?

 

[Golddigger Greg]

Any advice before I embark ?

As a start watch LazerSteves' videos to refresh the recollection. That's what I did this afternoon before starting my first-ever batch! Thank you GRF and LazerSteve!

 

[butcher]

Sounds like great advice to me Golddigger Greg, that and a few chapters of Hoke's book.

 

[Monkey-boy]

If you keep adding gold to the AR till there is no reaction does that mean you don't need to boil off the nitric?

 

[Palladium]

If you keep adding gold to the AR till there is no reaction does that mean you don't need to boil off the nitric?

If you are adding a pure gold button and not just scrap gold then yes. The term boil is not correct when referring to dispelling nitric acid. It is refereed to as evaporating. You never boil to expel excess nitric only evaporate.

 

[butcher]

As long as you had free HCl in solution for the gold to dissolve into, and become gold chloride, the nitric would be consumed by oxidizing the added gold, if HCl was limited the nitric may not be consumed as there would be no HCl to dissolve the oxidized gold layer, also as solution saturates the action seems to slow, I believe heat is needed, or it could take very long periods of time for the final reactions to completely use up the nitric in solution.

 

[Harold_V]

If you keep adding gold to the AR till there is no reaction does that mean you don't need to boil off the nitric?

You NEVER "boil off" nitric acid. Please do not make mention of evaporation as boiling. I get down right unreasonable with readers who do so..

Harold