Non-Chemical Question about ball mills and Cyanide.

[NuggetHuntingFool]

Everybody.

If I was to crush memory, expansion cards, processors and motherboards in a ball mill. Is a ball mill the wrong way to go? I'm thinking everything would have to be crushed fairly well, at least 1/4"x1/4" pieces perhaps even smaller.

Would I be able to leach everything out with cyanide solutions? As far as the Ag and Au?

What's the way to tell if Cyanide is fully laden with precious metals and can't dissolve anymore?

Will the Cyanide pick anything else up from the boards or only Ag and Au?
From what I understand, Cyanide is very selective but I'm unsure of the details.

Any ideas??
Does anybody work this type of technique?


Thanks.

 

[NuggetHuntingFool]

Looks like it's high-time to hit google books for a Cyanide Leaching book.

 

[Lou]

In low concentrations cyanide is good for gold and silver. The more you put in typically the more it will pull out in the form of base metals. Even then though, it's not as if you can't wash/dissolve those out from material cemented from gold and silver cyanide.


Lou

 

[NuggetHuntingFool]

I'm thinking some halides might be a better idea for this sort of thing.

What do you guys think?

How would you all tackle the PM's in a ton of crushed e-scrap??

Obviously acid is out of the question.

Cyanide or Halides? I'm curious as to which will grab the Ag and Au exclusively without touching other metals. Not sure if this is even possible but a curiosity nonetheless.

 

[Lou]

I would go with cyanide; as GSP said once, it's the cat's meow when it comes to extracting gold from low value material. Problem is acquisition. For people without a business license and all, that is probably very difficult. It's also not cheap coming from a chemical supply house. It ought to be $5/lb in technical grade in 25kg sacks. I know for a fact that Legend Mining Supply in Reno used to have 5lbs of cyanide for $100 or so. I think it was pickup only, most likely so they could ask you what you needed it for!


You can use the HCl-Cl process (bleach and muriatic acid) with powdered material, but you'll also pull out a variety of things, and you may lose some of the silver.

 

[skippy]

Lou, I know one of the more senior refiners around here was talking about cyanide stripping plating from plated jewelry and mentioned the use of a buffer to improve the selectivity of the cyanide. Would the buffer be essential to the use of cyanide on the sort of escrap Nuggethuntingfool
proposes?

 

[Lou]

Yes, and this very same type of chemistry was discussed by GSP.

http://goldrefiningforum.com/phpBB3/viewtopic.php?t=3035&start=15

 

[eemtek]

if you cannot find cyanide, try a thiosulfate.. you can buy it quite cheap.. Try a&b prospecting in phoenix az.. after you think you got all your precious metals with AR out of the chips, try it again, and again, you will see that there is a point it actually plates out on the chips.. I have overcome that with pot cyn, but I would believe thiosulfate would work.. If you just want to pull it to a bar, get a smelter, #8 crucible and crush the chips to powder. add normal flux with a 1/4 ration of CaO. then add half the chips weight in copper. I use wire that is silver plated to catch the silver too.. smelt for a few hrs, and drop as ingot of ball it out in water.. this is easier than the chems, but the toxins released are scarry.. hope this helps

 

[butcher]

how did ole time miners get their cyanide, I doubt they bought it at chemical warehouse or ordered from Ebay, (seeds of fruit), couldn't we make it? from what I see it could be safer used properly,than thiosulfate?