Gold recovery?

Discussion in 'The DIY corner' started by Brian K, Feb 18, 2020.

  1. Brian K

    Brian K Resident Douchenozzle Charter Member Supporting Member

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    Anybody ever attempted any gold plate recovery with HNO₃+3 HCl? Or know small refinery local to the triad they trust?

    I've been watching videos, it looks pretty straight forward - use PPE and a fume hood. I'm no chemist but I can read, comprehend, and follow directions. Found a supply house online that has all the chems I'd need minus the HCI.

    I ended up with about 40lbs of plated scrap, based on weight, shape, surface area, and plating thickness I'm guestimating a 0.004 yield which works out to ~2.5oz or $3800.
     
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  2. ronn47

    ronn47 Where's the Scotch? Charter Member Benefactor Life Member

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    If you end up doing this please provide us a write up.
     
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  3. bigfelipe

    bigfelipe Phil-osopher... Charter Life Member

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    Could you scrape it all off and just smelt it down with some flux and skim the impurities off like lead for boolits?
     
  4. MacEntyre

    MacEntyre Shoot on Sight! Charter Member Vendor

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    Aqua Regia works. Just be careful, 'cause it is a strong acid with dangerous fumes!
     
  5. random

    random Active Member

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    A chemical supply house that has nitric acid but not hydrochloric acid? That seem rather odd. But if you don't need a high concentration or reagent, muriatic acid is basically just 40%(-ish) HCl.

    Agree with the sentiment - share what you learn!
     
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  6. Brian K

    Brian K Resident Douchenozzle Charter Member Supporting Member

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    They have HCI, it's just way more spendy than muriatic at Lowes. And at 4:1 I'll need a lot to process 40lbs.
     
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  7. random

    random Active Member

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    Ah, must have misunderstood, then.
     
  8. Brian K

    Brian K Resident Douchenozzle Charter Member Supporting Member

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    Dude... It's 20000+ pins.
     
  9. bigfelipe

    bigfelipe Phil-osopher... Charter Life Member

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    Ah... You didn't specify what the plated material was... Carry on...
     
  10. Brian K

    Brian K Resident Douchenozzle Charter Member Supporting Member

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    New question. Watched a video of a guy doing exactly this with the same style material. He used a boat load of nitric to dissolve the base metal (brass - same as my stuff) before moving onto the aqua Regia. It's that necessary? Can't I just go straight for the aqua Regia?
     
  11. JimB

    JimB Picking it up slowly. Benefactor Charter Life Member

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    Do you have a place that will convert this recovered gold to cash? At what rate?
     
  12. DrScaryGuy

    DrScaryGuy Well-Known Member Supporting Member

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    So you want to dissolve everything together instead of removing the impurity that is going to be over 39lbs of your 40lb starting material?
     
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  13. Brian K

    Brian K Resident Douchenozzle Charter Member Supporting Member

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    Not yet.

    Well. Dammit. You're right. It seems aqua regia would dissolve the brass too. And enough nitric acid to dissolve just the brass is too spendy, plus all the time to make an entrance for the acid on every pin. So I'm shifting directions and looking into reverse plating with a sulfuric acid stripping cell. It'll require less nitric and more cheaper sulfuric acid - and leave the brass intact.
     
    Last edited: Feb 19, 2020