>I'm thinking about retrieving silver electrolytically from ordinary
>photographic fix (i.e. ammonium thiosulphate solution).
>It is possible, that's a fact. But I've got no informations about the
>electrodes, the voltage, the current, the mode (constant current or
>constant voltage etc.) and other basic things.
>Does anybody on this list has some informations about this ?

My father used to do this, extracting silver from the solutions of the
photographic shop where he worked. I do not know where he got the
information and equipment from, but it went something like this.

The solution was in a plastic container, about the size of a 10 litre paint
pail. This then had a stainless steel disc lowered into it, which had been
cut and twisted so it was like a single turn corkscrew. This disc was on a
shaft that was motor driven using a small ac driven motor. The silver
collected on the disc, and because the disc is stainless, was easily broken
off the disc to remove it. Rotation of the disc both stirred the solution to
enhance the collection of silver, and caused the silver to deposit more
evenly, which I believe helped to remove current "hot spots" from causing
localised heating of the solution.

I assume the other electrode was also stainless steel, but cannot recall it.
However doing a web search produced information that seemed to suggest
carbon or maybe iron (which would get eaten away and replace the silver in
the solution). I do not know what level of current was used either.

After removing the silver from the disc electrode he would then heat it and
skim the surface to remove impurities in the time honoured way.


Hope this helps you.

--
http://www.piclist.com hint: To leave the PICList
mailto:piclist-unsubscribe-request@mitvma.mit.edu