Aqua regia recipies?

[Jaxom]

Two part question. I've been alley crusing and dumpter diving for scrap metal for my welding shop for a bit. Then realized the benifit of turning excess scrap and metals I don't intend on welding in for extra cash. While doing this I've seen alot of electronics stuff being tossed away as well. Since electronics have alot of copper in them I've been collecting them as well. But now I've got a garbage can full of printed circut boards. I thought of tossing them and I'm glad I didn't! Good thing for google because that's where I found out about doing gold recovery using A/R method of recovery.

I did happen upong the Shor website but from comments made here and on another board, it seems they sort of expensive for supplies you can find locally.

So, my first question as a newbie is does anyone have a link for simplified A/R method. I've bumped into a few doing a google search and the authors are so confusing they have me scratching my head, and that's after reading them over a few times.

My next questions is how about how to prep the boards prior to doing the recovery. With as many boards as I have, it'd be very time consuming to remove the bits and pieces that may contain gold in them. Instead I've tried to think of ways of breaking up the boards. One suggestion is to build a small ball mill and let the boards tumble around for a while until pulverized.

It would take a rather long time for a small ball mill to pulverize a full sized mother board out of a computer, let alone the chips on it. So I was wondering if anyone has built themselves some sort of board shredder. I'm handy motors and gears and things, would think something could at the very least break the boards up into coin sized chunks or smaller before putting in ball mill.

This leads the next issue I need to work out. After running in a ball mill for a while I end up with a semi fine material to be soaked in the A/R, by dumping the material in there it'd just pile up at the bottom. I don't think this would be efficent since powders addd to a fluid often encapcilate and don't mix well with the liquid. My solution is to get one of those lab stirring plates what use a magnet encased in glass. Does this sound feasible enough?

And finally, as I understand the A/R method. After soaking long enough, I can then pour off the A/R with the now dislolved metals. I'd of course want to filter the liquid as I did so to capture any waste solids. Now, from what I've read you add enough parcipitant (going by how much disloved metal is in the A/R) to the A/R to cause the gold to drop out of the A/R. How do you know how much metal has been disolved during the soak, so you know how much partcipitant to use?

I hope that all made sense!

Jax

 

[Oz]

Hey Jax,

Welcome, and yes it made sense. You might want to consider looking into the AP process before you get that involved and buy a lot of equipment for electronic scrap. I noticed you finally got into Steve’s site and he has great tutorials there on it as well as great amounts of info on here. Use the search at the top of the pages for “AP” or “Acid Peroxide”. One of the easiest as well as most productive methods with electronics is processing fingers with AP. Enjoy!

 

[Shaul]

Hi Jax;

You say you've got a garbage can full of circuit boards and that you think it would be too time-consuming to separate out the gold-bearing material from them.

Well, I've got the equivalent of 50 or more 'garbage cans' full of boards to process and I'd still rather go through each one individually and pull the pins etc. than throw the whole thing into the mix.

It may seem easier to shred and crush the whole boards before you process them, but the more variables you add, the more complicated things will become.

Much better to start off with smaller batches of same-type material such as all fingers or all header pins etc. until you become proficient at what you're doing and then you can go on to larger quantities.

Besides, one trash can of material hardly justifies anything more than a heat gun and a pair of pliers.

Shaul

P.S. Buy Hoke's Book

 

[istari9]

That is what I have been doing, even before finding this site. I go through each board one at a time and sort all like material. Collecting the tools and equipment I need as I go. I felt that this method was the better idea. Then I found this site and the lights have come on! I have managed to process some fingers, in AP and have a cell operating. Using Steve’s suggestions and reading (rereading) Hoke, have given me a more in dept view of what to do and how to do it. I too have a garage and basement full of boxes of boards I have collected, and process every day. I even have a small amount I work on at my job. Take your time study and work your material as you go. This is a passion for metal(s) and business. I believe doing it right for the maximum profit and safety are important goals. Of course each to his own.

Ray

 

[Jaxom]

See this where I'm at a major loss. The sound card on my computer died a few months back. While I did see the pdf's on Steve's site, seems alot of the useful information is in the videos. Don't do me any good if I can't hear them!

And I really wish i could. I did as suggest and spent the day reading about the A/P method. That does seem alot easier and less caustic to work with. Although I can see where you still need to be careful and take precautions.

But this leads me to even more questions. Ones I might find answers to, if my sound card worked! ARGH!!!

Soo, if ya don't mind, while I try to sort out my sound issues, if I can get a some answers to more questions I have, this time about A/P.

As I understand the a/p method. You soak the boards in a solution of 2:1 of a/p. This could take some time to soak, even a few days. Instead of disolving all metals it just disolves the metals I don't want and leaves the gold intact (I'm over simplfying this of course)

After a thorough soaking you then was the rinse the boards with straight HLC a few times then with straight water (tap? or distilled?) Of course you've been rinsing the boards over a filter to capture any gold that's been loosened. You also filter the a/p to catch any gold that's floated free.

The gold also goes through the same rinse cycle as the boards did to help wash away any disolved metals.

Am I right so far?

So really I don't need to pulverize the boards into a powder, this would make a mess, but at the very least break up the boards and chips to pea size or so chunks so the a/p can disolve the metals holding the gold down.

I also understand that some gold can be leached into the a/p with too much peroxide useage, or using too strong of peroxide. And that this can be percipitated back out by using SMB... What is SMB?

And the last thing I was wondering about was when folks mentioned incineration. I think it was mentioned right along with someone taking the boards and puttting them into a crucible and letting the non metals burn off and then letting all the metals melt and then dribbling this molten metal into cold water so it forms "bullets" and then soaking them in a/p to disolve all but the gold. Atleast that's what I think it was... I'm a bit fuzzy on this.

FYI, I really wish I could buy that book everyone is talking about. But right now money's tight, it's gonna have to wait a bit.

Jax

 

[Noxx]

Hey Jax,
You are right about the AP process. Also, you don't need to use distilled water.

The book everyone is talking about is available for free ! Please check in the book section.

Have a good day.

 

[istari9]

Let’s take your sound card, as it appears in parts.

1. Fingers the gold colored little edge that would plug into the PCI slot
2. IC's flat chips that populate the board, crushed MAY yield some small amount of gold, remove steel and any copper traces that pull up with it (them).
These are best to save until you have a lot to process, which would yield more if crushed (say in a ball mill) till it is a fine power. Watch the steel fingers inside some have gold plating on them.
3. Capacitors have Alum exterior paper and foil with a bit of oil inside. I save for alum scrap. Need a huge amount for any real value.
4. The steel plate on the end and the screws that hold it. 1ton is about $200.00 I save up about 2 or 300 lbs for whatever it can yield at the scrap yard.
5. Serial port has either a pin inside with a small amount of gold plate at the tip of the pins or is completely plated.
6. Speaker ports have either a non-magnetic tin or steel or somewhat lightly gold plated steel innards.
All of the parts make up the card but for best results in refining all parts process with amounts of like kind.
Pins can be done with A/R I guess heated or with a Cell ( my preference).
Harold has a great post on cleaning and incineration before process.
This forum has a huge amount of posts including links to what to save that has value and what is junk or lesser values. I save all copper alum steel and small parts for further processing. I even save copper clad boards for sale to refiners who do that work. This is a very labor intensive Hobby. But the rewards a beautiful (if you like the color of GOLD!)
There is always the resale as a complete board on this forum or E-bay for a quick profit, with very little work. I have purchased them from both, just to increase my supply of stock. I hope I have given you some light at the end of the tunnel. I would look on the forum for the words to fill in Steve’s videos and down load Hoke it is here and FREE. Have fun be safe, ask questions. I have welded for some 20 years and I just found out a rosebud is better then a welding tip according to Hoke. I figure there is always room to improve and build on a knowledge base.

Ray

 

[junkelly]

3. Capacitors have Alum exterior paper and foil with a bit of oil inside. I save for alum scrap. Need a huge amount for any real value.

Have you successfully sold these to a scrapyard? I quit saving them when I read someone (hyderconsulting?) suggest that nobody was willing to buy them.

-junkelly

 

[Jaxom]

Can plated jewelry be processed the same way as electronics scraps are with a/p? Had a grandparent that once worked for a major corporation that no longer exists. Some how he got his hands on 5 lbs coffee can full these service award pins for years worked at this company.

 

[Rag and Bone]

The sulfuric cell is excellent for plated items. Ap would need to dissolve lots of base metals for a little gold. AP is probably not the best method.

That said, I just sold a pound of costume jewelry for a ridiculous amount on ebay.

 

[istari9]

Junkelly, I have not sold them (capisitors) however I was thinking of stripping the alum from them and making it look like just alum. Perhaps melt it into a bar or brick...

Ray