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dhcracker
Ok Gang,

I've been collecting Gold scrap and I have about a 5 gallon bucket full of cpu's, fingers, and odd ball stuff not to mention the old video equipment in the garage I haven't even plundered yet!

I'm wondering what the best method is. I want to simply make my own chemicals if I can, wouldn't it be better to simply buy some muriatic acid and concentrate that? I would simply have a 5 gallon bucket of acid, a 5 gallon bucket half full of distilled water and put them in a sealed box for a couple weeks to concentrate it.

The tricky part would be making enough concentrated nitric acid. What about the re-agent? Any ideas?

I've never done this before but I routinely dissolve copper from transformers in HCI so I should be able to tackle this.

Next I want to start collecting pgm's from cat convertors.
Montec
Hello dhcracker

Nitric acid by itself will not dissolve gold. However nitric acid will work to remove silver and copper from said circuit boards. The silver can be precipitated out of solution with common table salt. For gold you will need aqua regia. Check out this link for details.
smile.gif
dhcracker
QUOTE (Montec+Sep 21 2010, 06:46 PM)
Hello dhcracker

Nitric acid by itself will not dissolve gold. However nitric acid will work to remove silver and copper from said circuit boards. The silver can be precipitated out of solution with common table salt. For gold you will need aqua regia. Check out this link for details.
smile.gif

Nitric acid and HCI dissolves gold, it takes both thats what aqua regia is my friend.

Sorry I should have mentioned that, I already have the HCI just didn't think to mention it oops.

H202 is used as well smile.gif

Montec
Hello dhcracker
I ran across this article. It seems to be what you are looking for.
smile.gif
former jeweler
QUOTE (dhcracker+Sep 21 2010, 02:59 AM)
wondering what the best method is. I want to simply make my own chemicals if I can, wouldn't it be better to simply buy some muriatic acid and concentrate that? I would simply have a 5 gallon bucket of acid, a 5 gallon bucket half full of distilled water and put them in a sealed box for a couple weeks to concentrate it

The color of vaporized copper is one of the most beautiful you are likely to see ever seen and it can only be seen when you put copper -gold or not- into concentrated acid. Upon see-through and under sunlight, the colors that you see behind that vapor are all supersaturated and it's an evanescent phenomenon, gone in a fraction of a second -it's a unique effect, unfilmable, and that seems to never have been documented before. The meeting of acid and copper is explosive and that vapor is very, very toxic, but it's fantastic to look at especially under sunlight -trust me on it: avoid closed rooms for this. The "best method" is oldest, the way jewelers do it. Supposing iron is off the picture with an acid bath, melt metals together and put them through any one of these:
www.abm-corp.com/abm_metalmachines1.htm

O.k., smaller versions exist even on other fields: these machines are the jewelry version of
www.kitchenkrafts.com/product.asp_Q_pn_E_BE0083

You will be left with a very fragile-looking tin-foil like film. That is what goes into the concentrated acid, very very v e r y slowly... and later on you recover the dust from the bottom and melt it. That is the gold.

There are numerous specifics to this process that aren't quite fit for this space but any jeweler would tell you with plenty of details.

But is it cost-effective as far as recovered gold from electronic parts is concerned?

Not a chance. Only for jewelers, who actually collect their own trash so that any eventual dust gold in it can be recovered. (Remember a vat where three jewelers had to wash their hands before they washed their hands every time they left the room, no exception. The water was changed every day multiple times, of course. From their hand's dusts they recovered about 30 grams of gold from the bottom of the vat after 3 years.)
home refiner
QUOTE (former jeweler+Sep 28 2010, 05:44 AM)
The color of vaporized copper is one of the most beautiful you are likely to see ever seen and it can only be seen when you put copper -gold or not- into concentrated acid. Upon see-through and under sunlight, the colors that you see behind that vapor are all supersaturated and it's an evanescent phenomenon, gone in a fraction of a second -it's a unique effect, unfilmable, and that seems to never have been documented before. The meeting of acid and copper is explosive and that vapor is very, very toxic, but it's fantastic to look at especially under sunlight -trust me on it: avoid closed rooms for this. The "best method" is oldest, the way jewelers do it. Supposing iron is off the picture with an acid bath, melt metals together and put them through any one of these:
www.abm-corp.com/abm_metalmachines1.htm

O.k., smaller versions exist even on other fields: these machines are the jewelry version of
www.kitchenkrafts.com/product.asp_Q_pn_E_BE0083

You will be left with a very fragile-looking tin-foil like film. That is what goes into the concentrated acid, very very v e r y slowly... and later on you recover the dust from the bottom and melt it. That is the gold.

There are numerous specifics to this process that aren't quite fit for this space but any jeweler would tell you with plenty of details.

But is it cost-effective as far as recovered gold from electronic parts is concerned?

Not a chance. Only for jewelers, who actually collect their own trash so that any eventual dust gold in it can be recovered. (Remember a vat where three jewelers had to wash their hands before they washed their hands every time they left the room, no exception. The water was changed every day multiple times, of course. From their hand's dusts they recovered about 30 grams of gold from the bottom of the vat after 3 years.)

Actually electronic scrap can be very profitable. Expescially if you have older type electronics from say 70's to early 90's, these electronics will have comparitavely very thick gold plating.

The way I would do it is first dissolve the copper and get rid of it, leaving the gold plating for your aqua regia solution. But I wouldn't start doing this unless I have like a 5 gallon bucket full of fingers, cpus, and pins and such other gold plated things.

But I have heard yields as high as half an ounce out of a 5 gallon bucket, so its definately doable. The most I have gotten out of a bucket was 4 grams 99.9% pure gold. But I had pretty crappy scrap this guy sounds like he has the good stuff.
marcustash
Nice Post.
Keep It Up.

Thanks
Capracus
A senseless obsession.
QUOTE
Some experts argue that we shouldn't have to mine new gold at all: We just need to let go all the shiny stuff we're hoarding. In 2008, it was estimated that 157,000 tons of gold had been mined throughout history -- and that individuals were sitting on a whopping 104,000 tons of it, in the form of bullion, coin and jewelry. So the best way for you to mitigate the impacts of gold-mining might be to make a personal pledge to keep gold in circulation. Try instituting a one-in, one-out policy for your jewelry box: Whenever you want to buy a piece of gold jewelry, take one you already have and sell it, or melt one down for refabrication. Do that, and you can glitter relatively guilt-free.
http://www.washingtonpost.com/wp-dyn/conte...0092004730.html
Capracus
We already have too much.
dhcracker
QUOTE (Capracus+Dec 18 2012, 05:25 AM)
We already have too much.

We?? Who exactly is we?? You can give us some because "we" don't have enough lol.

World governments like to keep their gold locked up and good luck bringing that gold into circulation!!

You know I went through this process with some of my electronics... I got more than I thought! I got almost half an ounce from almost a full 5 gallon bucket of gold plated electronic scrap.
AJKOER
Yes, HCl mixed with H2O2 can dissolve gold

A tip on making concentrated HCl, add FeCl3 to your dilute HCl and now you can concentrate it by distilling, even if it is very dilute to start.

krash661
what's an average cost for one of these home smelting kits ?
ph0t0bug
I sure hope someone has an answer for me. Ok Im gonna make it as short as I can:

1. Gold fingers, pins, crushed CPUs put into HCL with H2O2 to remove gold leafs.
2. Strained off the trash and flakes from the HCL and H2O2 and stored mixture.
3. Used fresh HCL with Household bleach to melt the flakes to liquid form.
4. Took, correct me please if Im wrong, the Auric Chloride and filtered out all the trash, stored, and then added, I think this may be part of my mistake, equal tap water to the Chloride.
5. Added Urea to nutrlize acid.
6. Added SMB to "drop" the gold out.

At this point I ended up getting nothing but clearing the liquid from yellow to clear. Nothing on the bottom.

Decided to test the liquid for gold. Used HCL and eletrical sauter to make test fluid. Took a small amount of the above liquid and got a brownish "mud" to "drop" in the sample. At this point I took a sample from the "Trash" that was collected and the reaction was even greater with darker mud and the yellow came back to the liquid.

Question is I guess.... Just what the heck did I make and is it recoverable or should I just get rid of this mix?

Thanks for any help you can provide.
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