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Electrochemistry Silver cell
- Thread starter ron c
- Start date
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Does the electrolyte seem to be contaminated with base metals, what is the Ph of the cell? Could you have gassed off your acid?
Looks like a nickel issue.
philddreamer
Well-known member
Ron, I think is more like "how do I get the silver out!"
I would cement the silver with copper and rinse the silver properly. I would them dry it & weigh it, thus making sure you had 100g of 99.95 when you first started. Then melt new anodes & try again.
From the contamination present in the solution, I don't think your silver was 99.95% when you started; more like 90% or so. What was the source of that silver? Did you refine it yourself?
I tried running 92% or so anodes once as a test, & this is what my solution looked like...
Take care!
Phil
P.S. Did you use a anode "bag" for catching the black sludge?
I would cement the silver with copper and rinse the silver properly. I would them dry it & weigh it, thus making sure you had 100g of 99.95 when you first started. Then melt new anodes & try again.
From the contamination present in the solution, I don't think your silver was 99.95% when you started; more like 90% or so. What was the source of that silver? Did you refine it yourself?
I tried running 92% or so anodes once as a test, & this is what my solution looked like...
Take care!
Phil
P.S. Did you use a anode "bag" for catching the black sludge?
Attachments
Once, in my 30gal cell, the crystal shorted to the anode and it burned a hole in my anode bag. Some of the anode slimes, which are most always black or dark, fell through the hole and contaminated the solution and crystal. I spent all day filtering the solution, remelting the silver, and cleaning the tank. Before filtering, the solution looked identical to that in Ron's photo. I know that color.
So, either, (1) There's a hole in the anode bag. (2) The bag material is too coarse and the slimes are penetrating through it. (3) Maybe you got it too hot from too much amperage and the small amount of nitric present ate at the bag. (4) Maybe it didn't get too hot, but there was too much excess nitric when you made it up and it eventually ate through the bag. (5) As Geo suggested, maybe you're not even using an anode bag.
Gotta have an anode bag. I have never run anything that did not produce some anode slimes and they were usually black. Just look at the anode (Ron called it the cathode).
So, either, (1) There's a hole in the anode bag. (2) The bag material is too coarse and the slimes are penetrating through it. (3) Maybe you got it too hot from too much amperage and the small amount of nitric present ate at the bag. (4) Maybe it didn't get too hot, but there was too much excess nitric when you made it up and it eventually ate through the bag. (5) As Geo suggested, maybe you're not even using an anode bag.
Gotta have an anode bag. I have never run anything that did not produce some anode slimes and they were usually black. Just look at the anode (Ron called it the cathode).
Muslin cloth is what i have been using. They have it at wal-mart. I bought a piece big enough to make an average size flag for $3. I tried and tried to find out what the thread count was but never did. I just bought it and doubled it up into two layers and it works fine. Been using it for a couple of months now without a problem one. Well besides burning a hole once or twice. You live, you learn. :mrgreen:
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One of the possibilities can be that there has been a depletion of silver in the electrolyte, often caused by a concentration of slimes that is too great to slough off without assistance. I had that problem on several occasions when the level of platinum and palladium rose beyond acceptable limits in my cemented silver. Because no silver can penetrate the slimes at the anode, the cell depletes the silver, then starts co-depositing what ever constitutes the slimes. If the slimes do not fall free of the anode of their own accord, that is a distinct possibility.
Depending on the nature of one's cell, it isn't necessary to re-melt the silver that has already been parted. Simply place it in the anode basket with an anode on top. The once parted crystals will part perfectly well. Been there, done that, on more than one occasion.
I highly recommend that new electrolyte be used, needless to say.
Harold
Depending on the nature of one's cell, it isn't necessary to re-melt the silver that has already been parted. Simply place it in the anode basket with an anode on top. The once parted crystals will part perfectly well. Been there, done that, on more than one occasion.
I highly recommend that new electrolyte be used, needless to say.
Harold
Ron,
Unless I missed it, you never did say what your anode is composed of. I made an assumption earlier that the photo was of the anode and not the cathode. Was I wrong about this?
Also, if the anode bag or filter is made of a material that is too tightly woven, it can act as a diaphragm and this will quickly deplete the solution of silver.
Unless I missed it, you never did say what your anode is composed of. I made an assumption earlier that the photo was of the anode and not the cathode. Was I wrong about this?
Also, if the anode bag or filter is made of a material that is too tightly woven, it can act as a diaphragm and this will quickly deplete the solution of silver.
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Absolutely true, but it takes a very thick bag, which is also tightly woven. My first experience was with some 1/8" thick cotton filter media. It was borderline too tight. I then switched to different material (also purpose made filter media---cotton, with one surface abraded).goldsilverpro said:
Harold
