I have watched a few of this guys videos for several years now. He is pretty sharp, and it shows with this video.
Step by step instructions for AP processing circuit boards
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Here is a video of the type barrel I had in mind.
Barrel plating
This barrel has small holes allowing the solution to flow through it and around the material. This machine itself, with a lid to cover it is another idea I have been thinking on for several years. Just replace the plating solution with AP, or even ferric chloride.
Barrel plating
This barrel has small holes allowing the solution to flow through it and around the material. This machine itself, with a lid to cover it is another idea I have been thinking on for several years. Just replace the plating solution with AP, or even ferric chloride.
Is that a plastic barrel?
I had one like that that just held a 2 gallon bucket...worked great until I used it in the hood too many times (it lived in there).
How does one recover gold from thiosulfate? I know it's completely off topic, but I've still got a bucket.
It is a viton rubberized coating.
Thisosulfate is used to dissolve the Silver Chloride that coats the gold making the reaction stop in stone removal. The thio dissolves the Silver Chloride and very little of the Gold exposing the gold alloy that was encrusted. The Silver is recovered by passing the liquid through a steel wool canister used for recovery of silver from x ray film used by dentists who still do X rays rather than the new digital style.
Thisosulfate is used to dissolve the Silver Chloride that coats the gold making the reaction stop in stone removal. The thio dissolves the Silver Chloride and very little of the Gold exposing the gold alloy that was encrusted. The Silver is recovered by passing the liquid through a steel wool canister used for recovery of silver from x ray film used by dentists who still do X rays rather than the new digital style.
Ok...so not a ton of gold loss then. I used it to dissolve silver chloride on a stone removal, then my gold numbers were low (per the seller of course), and it was the only place I hadn't "looked".
Wasn't sure if there was a faster way than the degreased steel wool.
When I first started tumbling with thio we had sweeps capabilities so the waste liquids were evaporated to a slurry and added sawdust (so it actually came out of the burn tray) when I had a full drum of the sweeps I assayed it and it had just a hair under an ounce of gold from over 200 half to full kilo stone lots. And the sweeps had about 350 ounces of silver in them. This was many moons ago but it was an insignificant quantity of gold from over 4000 oz of jewelry processed. So I never worried about using it on a customers material.
Thank you! It makes a stone removal so much easier.
Ok, I've been thinking about this. Are there disadvantages to just smelting the silver thiosulfate? Is it just a melt with iron to reduce it?
Did the solution change color over time?
Of course, all solutions change colorcas they become more saturated by Copper.
If you want to speed yours along, in a separate container get some fine chopped copper wire, or just stripped wire...but you want small diameter wires. Burning them ahead of time makes it even better. Not melting, just heating up to get them oxidized. Welding lead is what I had on hand. Add HCl and peroxide, and an aquarium bubbler for agitation, and very gentle heat. Keep adding peroxide until it's good and green and maybe even the wire dissolves completely. Once you are done adding peroxide and are happy with the concentration of copper bring it to a boil to expel any remaining chlorine. Cool and put it in the bucket that's not reacting.
The waiting period of making fresh A/P is torturous. But adding too much peroxide with gold present has some risks of ending up with finely divided gold to get the reaction kicked off, whereas adding too much with only copper present doesn't have that risk. Once you have copper chloride present, the reaction takes off that much faster.
I have had success processing large volumes of high quality pins/connectors in AP ~ 4.75 Kg total (in 1 Kg batches).
You are right Shark, it was a pain. It would often "clump up" and form white crystals - to which I added another 1 gallon of HCL, while breaking-up the clump with a long rod. Another time, the reaction appeared to have stopped for about a week (showing no white crystals) - to which I added a bit more peroxide. I always had an air bubbler running.
I have two buckets of AP running since March 2024 - one with pins, and the other with HP and Tektronix boards. I have been cycling material "out and in" of each bucket every Saturday morning since March. I started filtering bucket number 1 (pins) and it looks great. Bucket #2 (HP boards) will hold most of my values.
The photos shown below is the resulting "mash" obtained from 1 Kg of pins and several small, gold plated electronic parts.
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Forgive me for asking dumb questions but what is AP? Is it related to AR? Us newbies have trouble understanding jargon - like what exactly are pins (there are many types I'm sure) or fingers? I would very much like to try your bucket handling process but how to make the necessary AP soluation? Thanks! Taleeho
https://goldrefiningforum.com/members/frugalrefiner.23255/
A glossary of common refining terms.
But, AP is a misnomer for acid/peroxide. Better yet it uses hydrochloric acid and a fish aquarium pump to supply oxygen to the HCl. This in turn dissolves copper and some base metals. Please study up on it a bit more before trying to use it. And no more peroxide is not always better.
Also know by a better name as CuCl2
AP comes from Acid Peroxide and is derived on how it was run/started in the beginning.
It is actually a Cuprous Chloride etch where Copper goes back and forth between Copper I Chloride and Copper II Chloride with the help of Oxygen in the liquid.
The Oxygen can be provided by Peroxide or better with an aquarium air bubbler.
In the transition between the two Chloride states the Copper Chloride picks up a new Copper atom and as such dissolves the Copper in the target.
This process is very well suited to dissolve the Copper behnd the Gilded contacts on PCBs (Fingers) or less effective on pins from CPUs and other equipment.
Much of this inefficiency comes from the fact that pins are usually made from Kovar an Iron alloy.
All this is in here on the forum so a simple search should have solved this for you.
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An example of gold plated pins/connectors is shown in photo 1.
An example of fingers (edge connector) is shown on the edge of the white-colored board in photo 2.
With respect to your questions of AP and AR, I will leave that to the pros here.
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Per 4metals, I am adding this to the list of scrap types that lend themselves to the AP process.
I have successfully used AP on these small gold plated, copper items from microwave oscillators. It took about 2 weeks to fully dissolve the base metal. Photo included: Before - During – After
I have successfully used AP on these small gold plated, copper items from microwave oscillators. It took about 2 weeks to fully dissolve the base metal. Photo included: Before - During – After
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what a beautiful vintage board.
Did you open the adjustable wire resistors?
three on the right.
there should be palladium sliders that move along the rheochord...
Just re-awakening this thread to see if there are more comments before putting it in the moderator curated searches. If any of our members experienced with this process can recommend additional threads to review for a targeted search I would appreciate the help. Remember this is just for AP processing!
