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  1. #11

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    I kind of have a hard time following what you are proposing, but I think you are saying you want to take the bad paper, remove the silver from the paper with fixer, and then you want to put the silver back into the paper using electrolysis.

    It's that last step that will not happen. I assume you think that electrolysis will create silver metal, which you think will react with the sodium chloride that you've added to the fixer solution - and then the sodium will be left behind as free metal?

    That's not going to happen - remember that the sodium in the sodium chloride is ionic sodium. It's in solution and it will stay in solution. If you drop out the chloride ions from the solution with the silver, you still have the ionic sodiums floating around. I thint what they will probably do is start raising the pH of the solution.
    you seem to have misread the thought (I can see why, I am not very good at wording things sometimes), I thought about taking the silver as a cathode and use a salt anode (the chem teacher here has one, I would use the hydrogen b/c I can then make one, but that would produce HCl acid) and using electricity, cause the single displacement reaction:
    Ag(s) + NaCl(aq) --> Na+ (s) + AgCl(aq)
    but that would be dangerous...

    also, I do not have in mind financial benefits, but I hope to A) safely dispose of my spent fixer B) make use of the ruined paper some how, and I have been doing projects in making my own emulsions, and I thought I might find a way around using silver nitrate since it is hard to get a hold of and not something I would want to sit in my house for a long time C) learn more about electrolytic solutions of metal salts

    also, I think that if the unaltered (though exposed) silver chloride were lifted from the paper, and put into an aqueous solution, the ions (having broken apart into Ag+ and Cl- [or Br- etc] would lose the effects of having been activated, at least if a current was used with a sacrificial anode (the cathode would also be silver, but after noticeable changes to the anode and cathode, the current would be reversed)

  2. #12

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    Quote Originally Posted by knoxissimpler View Post
    then where would the sodium go? it would be a single
    replacement reaction if it happened, would it not?
    Should there be any instantaneous production of free
    sodium it would immediately combine with water forming
    sodium hydroxide and free hydrogen. Dan

  3. #13
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    Sodium hypochlorite also seems to be a possible product. Calcium hypochlorite (Chlorox) is very unfriendly to gelatine, so I would expect the sodium compound to be as well or more so.

    A rehalogenating bleach such as is used in the bleach-redevelopment method of sulfide toning, would be a better way to get a rudimentary silver chloride emulsion out of thorouhly exposed and developed printing paper emulsion, I would think. If you experimented with sodium chloride and/or sodium bromide in different proportions in the bleaching solution, you might get something interesting. At least you'd have a little fun trying.
    Gadget Gainer

  4. #14

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    Quote Originally Posted by gainer View Post
    Calcium hypochlorite (Chlorox)
    Pat - Clorox is sodium hypochlorite.
    http://www.thecloroxcompany.com/prod...leach0505_.pdf

  5. #15

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    Quote Originally Posted by gainer View Post
    A rehalogenating bleach ...
    So following Pat's idea here, you could develop the exposed paper to convert the exposed silver halide into metallic silver, and then use a rehalogenating bleach to form fresh silver halide in situ. If it's done in the dark, I think it would be light sensitive at that point. Dry the paper and make some test exposures.

    It's a lot of work, but it would be kind of fun to be able to say you've done it.

  6. #16
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    Quote Originally Posted by Kirk Keyes View Post
    Pat - Clorox is sodium hypochlorite.
    http://www.thecloroxcompany.com/prod...leach0505_.pdf
    I guess I was thinking of the water purification pills we used to get with field rations. Were they not calcium hypochlorite?
    Gadget Gainer

  7. #17

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    Could be - it's used for water treatment. But I never served so I can't say.

  8. #18
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    Actually calcium hypochlorite was used as a powdered bleach. Keep it away from ammonia compounds, it will get nasty.
    Gary Beasley

  9. #19

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    Quote Originally Posted by Kirk Keyes View Post
    So following Pat's idea here, you could develop the exposed
    paper to convert the exposed silver halide into metallic silver,
    and then use a rehalogenating bleach to form fresh silver
    halide in situ.
    Skip the exposure and developer. Use a strong reducing
    agent in solution to reduce the halides. Perhaps oxalic
    acid would do and not leave a mess. Oxalic acid,
    rings a bell. IIRC it is used for some alternate
    photographic purposes. Dan

  10. #20

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    can you fix and wash all the paper
    and use it to coat with alt process materials?

    pt/pd, cyanotype or even hand coated silver gelatin ..

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