Solution Color Change during refinement

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i have been wondering about different ways to clean up these pins as well, as i have some. not 17 pounds, but some. what would you think about melting them into bars/plates and running them through a copper electrolytic cell, and then refining the slimes? it would take longer, but the cost input should be much less. and of course, you'd have to ensure that there is at least 75% copper underneath, but you guys have much more experience than i do. what do you think?
 
For a quality return on the copper your mix should be 97% copper and 3% other material. Any nickle will foul the electrolyte, and a few other metals as well, but volume of solution and amount of metals can allow for a slightly higher mix of metals. As another method, even a sulfuric stripping cell should work quite well.
 
For a quality return on the copper your mix should be 97% copper and 3% other material. Any nickle will foul the electrolyte, and a few other metals as well, but volume of solution and amount of metals can allow for a slightly higher mix of metals. As another method, even a sulfuric stripping cell should work quite well.
I've read that the sulfuric cell won't strip the inside. 90% of what I have are not solid but hollow and fully plated inside and out.

@Master Nater are yours the same?

Also, some are copper (probably beryllium alloy), some are brass and some are bronze. Would that mess up the stripping cell?
 
I've read that the sulfuric cell won't strip the inside. 90% of what I have are not solid but hollow and fully plated inside and out.

@Master Nater are yours the same?

Also, some are copper (probably beryllium alloy), some are brass and some are bronze. Would that mess up the stripping cell?
i believe most of mine are brass with gold plate. they do have some pain-in-the-butt stainless sleeves on them, but i'm working on removing those.
 
I've read that the sulfuric cell won't strip the inside. 90% of what I have are not solid but hollow and fully plated inside and out.

@Master Nater are yours the same?

Also, some are copper (probably beryllium alloy), some are brass and some are bronze. Would that mess up the stripping cell?
A sulfuric cell won’t work well if the pins are plated inside. The copper cell won’t handle bronze or brass very well, tin and zinc can foul the electrolyte. But, they can be reduced or even removed in the melt with flux’s or in some cases by sparging. Beryllium I am not sure about. Beryllium in pins is pretty rare as I understand it, but not unheard of.

There are many ways to do pins, some work better than others. The shape and make up of the material can be the deciding factor in how you work them. With 17 pounds you can try several different methods and compare notes on which works best for you and your materials. What you learn could pay dividends in later projects.
 
For a quality return on the copper your mix should be 97% copper and 3% other material. Any nickle will foul the electrolyte, and a few other metals as well, but volume of solution and amount of metals can allow for a slightly higher mix of metals. As another method, even a sulfuric stripping cell should work quite well.
all the way to 97%? that seems like a lot of mass to run through a cell just to get the copper out of the original material. can you explain what you mean by "quality return on copper"?

the purpose of running the material through the copper cell would be to remove the copper from the original material and get it out of the run, not to make pure copper. then the slimes could then be run through aqua regia to reduce the amount of material that needs to be ran. of course, that questionably pure copper could always be used again to inquart another run of other plated material to bring things to whatever % is necessary to run it through the copper cell again.

please let me know if my thinking is off. 97% just sounds like a lot of mass just to run an electrolytic cell. *fingers crossed*
 
i believe most of mine are brass with gold plate. they do have some pain-in-the-butt stainless sleeves on them, but i'm working on removing those.
I have a lot of that style too. Hot dilute sulfuric acid takes those right off leaving the gold plated pins. By hot I mean only around 190 F, that's all my hot plate will do but it sure works slick!
 
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all the way to 97%? that seems like a lot of mass to run through a cell just to get the copper out of the original material. can you explain what you mean by "quality return on copper"?

the purpose of running the material through the copper cell would be to remove the copper from the original material and get it out of the run, not to make pure copper. then the slimes could then be run through aqua regia to reduce the amount of material that needs to be ran. of course, that questionably pure copper could always be used again to inquart another run of other plated material to bring things to whatever % is necessary to run it through the copper cell again.

please let me know if my thinking is off. 97% just sounds like a lot of mass just to run an electrolytic cell. *fingers crossed*
If you run a high mass of mixed materials, example 75/25 copper to bronze or brass, the amount of metals that can and will foul the electrolyte will cause problems. Some of those problems can be poor electrical conductivity, poor copper quality, excess base metals in your slimes, and others. The excess of nickle, tin or even zinc can go into solution or stay with the slimes depending on several factors. In a very small cell, fouling the electrolyte is the main concern as poor electrical connections. If we have to little copper, the cell will start to produce light, spongy and fluffy copper from poor amp/volts. This can interfere with the ions moving between anode and cathode and leave even more base metals in the slimes. The big plus for copper cells is removing the copper into a means of additional income. Small scale it may not be much, but start moving 100 plus pounds of high quality copper regularly and it adds up quite well. Now the copper that is generally a nuisance is a profit maker. There is way more copper in most electronics than there is gold. We might as well make a salable product of the copper if we are going to use the copper cell besides just gold or pgm’s. By starting to do this small scale as practice the payoff later is time saved and more money made.
 
If you run a high mass of mixed materials, example 75/25 copper to bronze or brass, the amount of metals that can and will foul the electrolyte will cause problems. Some of those problems can be poor electrical conductivity, poor copper quality, excess base metals in your slimes, and others. The excess of nickle, tin or even zinc can go into solution or stay with the slimes depending on several factors. In a very small cell, fouling the electrolyte is the main concern as poor electrical connections. If we have to little copper, the cell will start to produce light, spongy and fluffy copper from poor amp/volts. This can interfere with the ions moving between anode and cathode and leave even more base metals in the slimes. The big plus for copper cells is removing the copper into a means of additional income. Small scale it may not be much, but start moving 100 plus pounds of high quality copper regularly and it adds up quite well. Now the copper that is generally a nuisance is a profit maker. There is way more copper in most electronics than there is gold. We might as well make a salable product of the copper if we are going to use the copper cell besides just gold or pgm’s. By starting to do this small scale as practice the payoff later is time saved and more money made.
Have you tried crushing them, brass can be brittle. Smack a couple flat with a hammer ...
 
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Have you tried crushing them, brass can be brittle. Smack a couple flat with a hammer ...
I have not tried to break them. Most pins will just flatten out . Some may break, but I haven’t tried much to do so on purpose. Small scale practice you can run a high mix ratio, you will see fouling, but it may not make much difference as the main goal is the pgm’s. Large scale the goal is copper production with a bonus of collecting the pgm’s. The slimes will not be clean even in a good working cell, in a poorly operating cell the slimes become even more dirty. But, the cell in this case is a recovery system, further refining will be needed to remove those base metals. Long term, the longer the electrolyte is cleaner the longer they operate with less input from the user.
 
Hi,
I did try iodine once. It is expensive and can work when there is no iron or nicel.
In my case more than 50 % of the solution did chatch not the gold then more the nicel plating under the gold foil. After dropping the metal everything was magnetic. 😁
 
If you run a high mass of mixed materials, example 75/25 copper to bronze or brass, the amount of metals that can and will foul the electrolyte will cause problems. Some of those problems can be poor electrical conductivity, poor copper quality, excess base metals in your slimes, and others. The excess of nickle, tin or even zinc can go into solution or stay with the slimes depending on several factors. In a very small cell, fouling the electrolyte is the main concern as poor electrical connections. If we have to little copper, the cell will start to produce light, spongy and fluffy copper from poor amp/volts. This can interfere with the ions moving between anode and cathode and leave even more base metals in the slimes. The big plus for copper cells is removing the copper into a means of additional income. Small scale it may not be much, but start moving 100 plus pounds of high quality copper regularly and it adds up quite well. Now the copper that is generally a nuisance is a profit maker. There is way more copper in most electronics than there is gold. We might as well make a salable product of the copper if we are going to use the copper cell besides just gold or pgm’s. By starting to do this small scale as practice the payoff later is time saved and more money made.
i'm not sure what % copper these bars were, but it was not very high. i do not have an XRF to test. they are simply some smelted silver-plated copper that i have hung in this copper cell. yes, i know how terrible they turned out. i'm working on getting better at the smelting process.

the first couple of weeks, seemed to go pretty well, as it was accumulating quite a bit of copper on the cathodes, and i even swapped them out a fresh set of cathodes as they were beginning to short across the bottom of the cell. now, it seems the sludge is accumulating on the smelted anodes, and not allowing any voltage flow from the copper. in fact, the last week or so, it sucked all of the copper out of the copper sulfate electrolyte solution and turned things inside the cell nearly clear. i'm assuming this is just dilute sulfuric acid as it was copper sulfate made from copper sulfate crystals dissolved in distilled water.

after reading and re-reading your post, this seems to be exactly down the line of thinking you were trying to warn me about. being a glutton for punishment, i had to give it a shot and learn the hard way... :(

so what options do i have to get this going again? i actually tried taking one of them, and wiping the sludge off of it, and rinsed it back into the cell. this just made everything murky, and threw the amperage through the roof. in fact, if i allow the voltage up to 3v, it begins producing little bubbles (which i assume is hydrogen gas?). so i turned the voltage back down to about 2.5v. can these anode just be wiped down in a separate cleaning cell and then put back in the copper cell, after exposing the copper under the sludge? could a little bit of nitric be introduced to the cell to eat up some of the sludge and keep things operating? or should they be re-smelted to a higher percentage of copper? as you can tell, i'm not very good at the smelting/pouring process and would like to avoid that if possible. especially, since i do not know what the % of CU is. if smelting is the way to go, what's to keep the sludge from reforming? simply having low enough impurities, that they will precipitate off the anodes to the bottom of the cell, instead of clinging and gumming up the works?
 

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A bit short on time so a quick reply ...
I use filter bags to catch the slimes in as it avoids mixing them in with other contaminants (somewhat). Simple non woven nylon or polyester bags glued together with hot glue works well. Unbleached Muslim cloth should work also. I used a tooth brush or a small parts brush in stainless steel to scrub the clingy stuff off but didn't put it back into the electrolyte. Since your copper has already played out of solution I would just make up a new batch and clean off the anodes before starting again. Since your already trying it for yourself and have see the problems first hand you might remelt them as well.
weight the anodes, add that weight in copper to it and remelt it. This way you can see the difference for yourself how the volume of copper changes things.
 
A bit short on time so a quick reply ...
I use filter bags to catch the slimes in as it avoids mixing them in with other contaminants (somewhat). Simple non woven nylon or polyester bags glued together with hot glue works well. Unbleached Muslim cloth should work also. I used a tooth brush or a small parts brush in stainless steel to scrub the clingy stuff off but didn't put it back into the electrolyte. Since your copper has already played out of solution I would just make up a new batch and clean off the anodes before starting again. Since your already trying it for yourself and have see the problems first hand you might remelt them as well.
weight the anodes, add that weight in copper to it and remelt it. This way you can see the difference for yourself how the volume of copper changes things.
thank you for taking time out of your day, to help. it is much appreciated.
 

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