Copper Refining Cell, but with brass anode

[snoman701]

I have been running a copper refining cell for a while, previously running on prepared copper dore that I had smelted outside. Nice flux and some creative oxygen purging and I was able to get a majority of my low melting point elements out of the mix. Well, I ran out of that alloy. And the cell sat for a year.

Now I have induction melted brass pins...and figured why not try. Maybe the zinc will just plate out with the copper....the lead will be in the slimes, so I'll smelt then cupel the slimes after cleaning them up with dilute sulfuric.

Everything started out great. It ran a couple days. I just kept topping off electrolyte with fresh as it evaporated. I think per liter, I used 160 g copper sulfate and 250 g sulfuric acid. Didn't have any gelatin, so I have a pretty moss like copper cathode. Then the moss like copper hit the bag, oops, but no short. Swapped out the bag for a fresh one.

Anyway, I ran about 5 lbs through it, and I started to get a greyish precipitate clouding up the electrolyte and adhering to the outisde of the bag (ordered from Anode Products).

Is this likely just the zinc precipitating as the free acid is consumed?

Realistically, my current hasn't dropped....so if I can just rig up a filter to keep the zinc? filtered out, I'll do that.

I haven't had any spills or obvious holes in my bag or anything. And yes, once I filter it out I can assay it for silver and gold to make sure I didn't screw up.

 

[FrugalRefiner]

GSP referred to them as floating turds.

https://goldrefiningforum.com/threa...how-i-attempted-silver-refining.427/post-4005
https://goldrefiningforum.com/threads/catalytic-converters.713/post-6390
Dave

 

[snoman701]

Thanks Dave! I couldn't find the posts!

So here would be the question. If I just set up a circulating filter, say something as simple as an aquarium filter...to collect the turds. Wouldn't that allow me to break down brass? The PM's should theoretically still stay in the bag right? I can deal with spongy copper or even floating turds....I just need to isolate the precious.

 

[nickvc]

Snow you are experiencing the problem that occurs when running too low a percentage of the desired metal when using electrorefining , when I ran sterling in the silver cell to recover gold and any PGMs I just kept adding more nitric to the electrolyte to dissolve some of the already plated fine silver thus increasing the percentage of silver to copper to keep the cell functioning , you could try that, ie add more sulphuric to dissolve more copper , and see if it works for you , alternatively you could harvest the copper from the cell and add to your feed stock to increase the copper content , either method should allow you to run the cell for longer to achieve your desired effect which is to recover your values .