Slow-cooking gold, is it possible?

[bemate]

Hi all!

I have tried searching the forum, but not found anything applicable yet, so I'll try asking and see if anyone can point me in the right direction or comment on my ideas.

My situation is as follows: I have access to a fairly limited, but steady, supply of e-waste, and not really the space to store neither large amounts of it nor making a permanent processing facility. This is just a side project for me for the time being, maybe not even enough to call it a hobby, yet.
What interests me is the chemistry of it, and of course the gold it could yield, but rather as a source of accomplishment than money.

What I would like to achieve is something along the lines of a slow leaching system that works with minimal input, and of course the least possible amount of dangers. Ideally, a solution/system/setup that will alow me to add small amounts of gold-containing scrap at a time, letting it leach the gold (and probably mosth other metals present) into solution or sludge that can be processed at a later date with better equipment and knowledge, but taking up a lot less space than complete boards and other e-waste would.

So, simply put, can I place my trimmed fingers, crushed flatpacks, CPU's, gold-plated pins and so on in a slow-working, not-too-dangerous solution and let time, rather than heat or aggressive materials do the work for me?

Thinking long term, I would then after months (or even years) be able to take my collected sludge/solution/whatever and process it properly to refine the materials present, having increased the relative concentration of metals, precious- and base-, to a much higher degree than untreated e-waste.

Writing this out, I will be the first person to say that this will produce a lot of mess, and will of course not be as simple as dumping a complete motherboard in a tank and have it strip itself, but is any part of this idea even remotely feasible?

Like I started off with in my title, I would rather work slow and safe, than fast and dangerous.

 

[jason_recliner]

Naturally the correct method depends on the input material.

IF you've access to a lot of copper clad boards with gold plated fingers, like in your other post, the copper (ii) chloride leach, aka Acid Peroxide (AP) method may be for you. You will find that in The Library. Err on the side of less peroxide. If you want to set and forget, you don't need any peroxide.

Your initial investment in physically removing everything "not golden" makes an extraordinary difference to ultimately reducing the time, effort and chemicals required.

Have a read, and we're here to answer any questions.

 

[nickvc]

Generally we like to keep different types of scrap separate including magnetic and none magnetic pins as the different base metals can cause one very big mess.
I would suggest you look into the AP process which is well documented here on the forum to start with it can handle many items and reduce the bulk somewhat, learning good recovery techniques and processes is vital in finally getting good refining results.

 

[bemate]

Thank you for swift replies, I admit that a single solution to cover all kinds of sources is a bit utopian, and probably not feasible. And just to point out, I have made a point of separating the different types of waste I've collected so far, primarily trimmed fingers from RAM and so on, separated coated fingers from plugs into magnetic and non-magnetic, as well as flatpacks and CPU's separate.

The material in my other post is pretty much typical, though more modern computer waste is also fairly common, so it's a mix.

Anyways, I'll probably pester you all with more questions as time goes on, but for now I'm still just stockpiling and sorting in what seems to be the best way, and maybe once I start doing any actual chemistry I'll make some posts if I come across anything worth mentioning.