Re: How to use steel wool silver sequestration method

RE: David Nebenzahl wrote:

dan.c.quinn@xxxxxxx spake thus:f> >
Precipitation may be a solution; an "easy way". The sulfide of
silver is even less soluble than the iodide. An excess of sodium
sulfide will strip the thiosulfate of it's silver and silver sulfide
will
settle to the bottom. I've only done it on a test tube basis.
The fixer could be used again were it not for it being loaded
with chloride, bromide, and iodide. Sodium sulfide likely sells
for a very low price. Dan

But even if you can do this, how would you dispose of the sludge?


If only silver sulfide, Ag2S, precipitates then I'd save the
sludge. We're only talking about a few grams. Ag2S is better
than 85% silver.
Carefull though that the fix is not acid. Stabbing in the dark,
I'd think a full teaspoon or two or three of sulfide per gallon of
fix would do. So, two bits for the chemistry?
I don't use the technique because my fixers are very dilute.
I put my trust in "dilution is the solution". I suppose I could
though. Another method is to use H2O2. That's a twist on
the oxidize the fix method. I'd think a bunch of sulfur
would then be mixed in with the silver sulfide.
Balancing all the equations would take Some doing. I don't
see any complictions with the addition of sulfide. A pure and
simple precipitation of silver sulfide should take place leaving
the bulk of the solution intact. Dan

.

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  • Re: How to use steel wool silver sequestration method
    ... silver is even less soluble than the iodide. ... sulfide will strip the thiosulfate of it's silver and silver sulfide ... Sodium sulfide likely sells ... would then be mixed in with the silver sulfide. ...
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