The funnel should let the fines settle to the center, and the valve should let me remove them without interupting the entire cell. Still need to mix up electrolyte, get a copper sheet and hook it up to my power supply.
Also I smelted two more cats, but had a furnace failure mid stream. So I gotta repair it and then re-smelt to extract more copper to work on.
Seems like a very sound plan. Look at an IKA mixer. You could maybe get a used one. That could help keep everything agitated and would probably help increase efficiency / recovery / reduce contamination.
This is kinda weird to explain, but any form of agitation at all is very carefully avoided. The PGMs that we’re after are super fine like silt and can, if stirred up, float around for a day or more. If any were to float up against the cathode as copper was being plated onto it, it could easily get trapped there and lost.
So Ideally, as the copper dissolves away from the PGMs, those fine fine fine PGMs just sink slowly to the bottom to be collected later.
I ditched the funnel though. It’s a good idea for when I’m a little better setup and running, assuming I keep doing this. I did get a 5 gallon bucket cut down and everything setup and running in it. The new batch of copper is cooling and will soon be put in, as I’m running through the old stuff now.
Side note, I splashed a little acid, and now I need new pants. Be careful kids.
Ahh gotcha, I think I misunderstood. Yeah mechanical entrapment is a real concern. Have you tried pre-extraction of the copper into a more soluble form while trying to keep the PGM as a solid? Hopefully once the copper is in solution it will stay that way but you can dose additives to improve conditions. Depending on the purity you need it may be cost prohibitive.
This (electro-refining) is the pre-extraction. Purity of the copper is a non-factor as long as I’m not entrapping PGMs in copper. Basically the copper is by-product / waste. So far I haven’t been able to find a faster better way to get rid of the copper short of nitric acid (too expensive).
Once I get down to mostly PGMs, then I’ll break out the more expensive acids.
