old pc -> gold

[bob000555]

I herd about a company that recycles old electronics. First they desolder any valuable components, then they strip the wires to recycle the copper. But where my question comes in. They chop off the tabs( http://cgi.ebay.com/3-pounds-of-gold-computer-connections_W0QQitemZ330078091564QQihZ014QQcategoryZ164QQrdZ1QQcmdZViewItem) and grind less valuable ic’s to extract GOLD. So here’s the question how do you think they separate the gold from the silicone/plastic. Perhaps with the connectors the dissolve the plastic in acetone leaving behind the gold leaf? Maybe the use the hno3/hcl mix stuff? Does anyone know?

[Comandante]

That's interesting, considering how many old computers get thrown away - collect all of them and you're rich!

 

I don't know how they would go with extraction but if it was me I'd first try some electrolysis (get some iron and plate it with gold off those parts and then melt it afterwards - just an idea) or bring everything to the melting point and separate things as I go along plastics will melt easily, then aluminium, and then comes gold around 1000°C, iron will stay as its higher than that... Just a few ideas If none of that works, I'd take a metal file and start grinding!

[ecoli]

I wonder how much gold could be in a PC.

[Comandante]

I wonder how much gold could be in a PC.

 

Yes I thought of that too, and did a little research

 

Here I quote http:// www.pcmag.com/article2/0,1895,2023990,00.asp :

 

 

Q: You point out that the average computer has a fair amount of gold and silver in it' date=' why is it so hard to get these precious elements back out?

 

A: The amount of gold or silver in a PC is actually a very small in weight—well under an ounce. But its value is significant so precious metals recovery along with recovery of copper, which electronic use quite a lot of, are among the primary financial incentives for recycling electronics. Both copper and gold, those industries told me, are virtually 100 percent recyclable. Mining companies were among the first electronics recyclers and have said that it's a lot easier and more efficient to mine a pile of old circuit boards than it is to prospect for and process the equivalent amount of ore. The mining industry knows very well how to recover both the precious and other metals in electronics. That's the comparatively easy part. The hard part is collecting the equipment for materials recovery.[/quote']

 

let's just say it's well under an ounce (1 ounce approx 28grams), let's make it 0.5 gram per pc, and it's probably more than that... now considering the price of gold http://goldprice.org/gold-price-per-gram.html 10 Pounds per gram, there you have 5 Pounds worth of gold out of a single pc? Is this the right minimum estimate?

[bob000555]

Apparently they use Aqua Regia, sodium cyanide, reverse electro plating, or chemicals. Which of the described options from this site sounds most plausible for home use? http://www.finishing.com/122/00.shtml

[jdurg]

Actually, when referring to precious metals any mention of "ounce" is referring to the troy ounce weight scale which is a bit different than the avoirdpoidus(sp?) system. One troy ounce is equal to 31.1 grams.

 

In older computers, they used to use a great deal of gold for the circuit board pins and various other components. Once manufacturers realized that you got the exact same results when you used a micron thick plating, they quit using actual gold wire and moved to an incredibly thin plating. Therefore, modern computers contain maybe half a gram of gold total if you are very lucky. In order to make it remotely profitable, you need to amass a MASSIVE, and I mean MASSIVE pile of old chips and circuit boards and be able to recover all of the gold without any loss otherwise it's just not worth it.

[John Cuthber]

The recovery of gold from old computers is often done in very poor countries where labour costs are very low and the environmental impact of the process is simply ignored.

[TATER]

What i would do to get the gold out of old computers is just take out the old cpu and snip off all the little prongs and instead of buying an entire computer just take the cpu out because the prongs are all gold

[jdurg]

What i would do to get the gold out of old computers is just take out the old cpu and snip off all the little prongs and instead of buying an entire computer just take the cpu out because the prongs are all gold

 

No they're not. Only the initial x86 processors and pre-pentium level processors are pure gold pins and those microchips have already been reclamated. If you read the post I made in here earlier, you'd have read that once manufacturers realized they could get away with a thin gold plating they started doing that on all their microprocessors. What was once a scant bit of gold then turned into a microscopic bit of gold.

[John Cuthber]

I rather doubt the pins were ever pure gold. It's so soft the pins would buckle rather than plug in. (Though I agree it would have been better if Tater had read the thread).

[TATER]

I always thought they were, but i guess im wrong