Reovering Silver from used Reversal bleach

Discussion in 'B&W: Film, Paper, Chemistry' started by htmlguru4242, Apr 10, 2006.

  1. htmlguru4242

    htmlguru4242 Member

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    I've got some used dichromate reversal bleach that's been used quite a bit. There's now a deep white sediment on hte bottom of hte container (I'm assuming that it's silver").

    Am I right, and, if so, is there a way to recover useable silver metal or silver salts from this?
     
  2. htmlguru4242

    htmlguru4242 Member

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    Still wondering about this ... does anyone know?
     
  3. m. dowdall

    m. dowdall Member

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    I did a search on 'silver recovery' and came up with many threads. Most were about recovery from fixer, don't know that it should be any different from dichromate.
     
  4. donbga

    donbga Member

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    Okay, I'll bite.
    When you say "useable silver metal or silver salts" I have to ask for what?

    From an environmental point of view it may be better to try to neutralize the dichromate, let the aqueous reversal bath solution evaporate and take the dried sludge to a reclamation center. There is no economically viable way to recyle small amounts of silver compounds. To make the process economically feasable you would need a lot of material to reclaim or recover. This unfortunately is especially true with silver prices being lower now than in past years when film and paper was king.

    IOW, it would cost you many times more to recover the metal than to just purchase silver nitrate crystals. A pound of AgNO3 would probably last the home darkroom worker many many years.
     
  5. lowellh

    lowellh Inactive

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    Silver chromate is insoluble. it will not "plate out". You can give it to a haz mat recovery company that will evaporate the water and the "cook" it to extract the silver
     
  6. m. dowdall

    m. dowdall Member

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    I did not know that. Guess you do learn something new every day.