Mmon2616 said:
Fonnie, I just read your post about the electrolysis units from printing companies. Do you happen to have the name or brand of the one you would recommend?
Michael,
I don't have an electrolysis unit from printing companies.
I've build one myself.
I've salvaged a fixerpump from an industrial x-ray automatic developer-machine.
With some (gardenhose) tubing and an anti-reflowvalve. I've made it possible to suck up the fixer from the jerrycan, and getting it to the plastic box.
Via an overflow the fixer runs back to the jerrycan.
on top of the unit, i've placed some plastic insulation strip/plate (2 plastic sheets with foam in between). in this strip i've drilled some holes the size of the arc-air carbon electrodes (the ones they use in welding, to remove groundlayers or weldingdefects)
In my setup I use 2 of them (those are the anodes), you just have to strip the very fine layer of copper of the electrodes.
I've taken 2 stainless steel strip (5cm wide, 35cmlong, thickness about 1mm). those strips are attached with a stainless screw on the side of the plastic strip, since it is a hard foam, i works well, and I can reposition them like I want. (those are my cathodes)
For a power supply I have a 15 volt 3A DC powersupply (Volt and Amps are regulated)
Connection to the anodes and cathodes is made with simple cables with bananaconnection and crocodileclips (don't know if the are called like that, but you get the drift.
Now for the electrolysis.
step 1 is to get the fix flowing
step 2 is to regulate the amps (supply in Ampregulationmode) according to the size of the cathodes, for me about 1.3 amps
the voltage will adapt itself to about 1.5V, but this depends a lot on the distance between the anodes and cathodes.
Let it run, and you will notice a light gray deposit on the surface of the cathodes, the recovery has started
Now you need to regulate the powersupply, as the fixer get depleted, you will have to regulate the amps, because you will have to keep the voltage from rising.
Don't push it, let it go, because to much amp and voltage will get you deposit of sulphides, and this means your deposit is less pure.
AgS will need to be stirred with an Iron rod, during melting to get rid of the S.
If you can avoid the AgS deposit, you don't get to treat it afterwards.
If allmost all the silver is recovered, you can unscrew the plate from the setup, and scrape off the silver. I use a Stanleyknive or a cookingplatescraper (has a sort of a razorblade in them
Next time I run a batch, I'll correct the values, because this is all from memory.
I'll take more pictures
And I found somewhere the correct (?) powersetting to surfacecalculation, but that to I will have to look up
I've posted somewhere in this forum a very helpfull publication from Kodak, it's called J10 and discusses the different systems of recovery.
For the moment I'm still pushing unused film trough the fixer (if time allows) so I can start the next batch.
Been busy with another project (non PreciousMetal related, building my own windmill)
about sending chemicals, please don't, Belgian customs-service will not be very happy, I think
@nickvc
I don't have special knowledge, and I'm not even doing the recovery as a business.
I really love/support the idea of Open Source, sharing everything to anybody, making a better world of knowledge, helping others, growing ideas,...
About the fact whether or not electrolysis is the way to go or not, like stated before, I did not calculate cost of equipment, nor cost of running the thing. Electrolysis is a way to recover silver from fixer, problem is it will not recover everything, so you will need another afterprocess. Hence my question about the zincproces
questions or comments
Let me know
best regards
Fonnie