Switch to English Language Passer en langue française Omschakelen naar Nederlandse Taal Wechseln Sie zu deutschen Sprache Passa alla lingua italiana
Members: 70,197   Posts: 1,531,433   Online: 838
      
Page 1 of 2 12 LastLast
Results 1 to 10 of 20
  1. #1

    Join Date
    Dec 2004
    Location
    Milwaukee, Wi
    Shooter
    35mm
    Posts
    3,242

    Source for Sodium Selenite

    I have in the past made Flemish toner directly from Selenium metal. My only problem is the very short shelf life of the mixed toner. Selenium metal is easily purchased and inexpensive. I am fully aware of the toxicity situation.

    Is it possible to make Sodium Selenite form Selenium metal? If so how would it be done.

    I know that it can be had as a mineral supplement in capsules but I would get very little chemical woth a great deal of additives.

    Does any one have a source for Sodium Selenite? About 15 grams would make approx. (1) gallon of a toner similar KRST.
    Claire (Ms Anne Thrope is in the darkroom)

  2. #2

    Join Date
    Jan 2007
    Shooter
    Large Format
    Posts
    284
    My gut was right. See here from wikipedia:

    "The sodium selenite salt is usually prepared by the reaction of selenium dioxide with sodium hydroxide:

    SeO2 + 2 NaOH → Na2SeO3 + H2O "

    Selenium Dioxide can also be purchased as Selenous (or Selenious) acid.

    If you can get selenium metal, then you can make selenium dioxide by either burning the metal in air or reacting with hydrogen peroxide.

    Two step reaction. Be careful. Should be a fun project.

  3. #3

    Join Date
    Sep 2002
    Location
    Willamette Valley, Oregon
    Shooter
    Medium Format
    Posts
    3,684
    Quote Originally Posted by Claire Senft View Post
    I have in the past made Flemish toner...

    Does any one have a source for Sodium Selenite?
    About 15 grams would make approx. (1) gallon
    of a toner similar KRST.
    I've a small quantity of sodium selenite purchased
    from a near by chemical supply house. There are
    transport restrictions as it is most hazardous.

    I've yet to make use of it. Do you happen to know
    of a formula which makes use of it? I do know that
    the elemental form can be dissolved in sodium
    sulfite solution. Dan

  4. #4
    eclarke's Avatar
    Join Date
    Jun 2004
    Location
    New Berlin, Wi
    Shooter
    ULarge Format
    Posts
    1,946
    Images
    71
    Scienclab lists 100g for about $70.00 Link.. http://www.sciencelab.com/page/S/PVAR/10426/SLS4189

  5. #5

    Join Date
    Dec 2004
    Location
    Milwaukee, Wi
    Shooter
    35mm
    Posts
    3,242
    Thank you all.

    Here is a formula for a product similar to KRST.
    Water 500ml
    Ammonium Thiosulfate 50% Sol. 100ml
    Sodium Sulphide 30grams
    Sodium Selenide 4grams
    Water to make a liter.

    This formula was listed in May/June Photo Techniques magazine. It was supplied by Dr. Robert Chapman. If you are going to make this toner I advise wearing a dust mask. It is highly toxic thru inhalation and or course ingesting it is also deadly.
    Claire (Ms Anne Thrope is in the darkroom)

  6. #6
    eclarke's Avatar
    Join Date
    Jun 2004
    Location
    New Berlin, Wi
    Shooter
    ULarge Format
    Posts
    1,946
    Images
    71
    Quote Originally Posted by Claire Senft View Post
    Thank you all.

    Here is a formula for a product similar to KRST.
    Water 500ml
    Ammonium Thiosulfate 50% Sol. 100ml
    Sodium Sulphide 30grams
    Sodium Selenide 4grams
    Water to make a liter.

    This formula was listed in May/June Photo Techniques magazine. It was supplied by Dr. Robert Chapman. If you are going to make this toner I advise wearing a dust mask. It is highly toxic thru inhalation and or course ingesting it is also deadly.
    If you are really in Milwaukee, check with Brian in the chemicals department at Laabs Pharmacy. I've bought many exotic chemicals form him...Evan Clarke

  7. #7

    Join Date
    Dec 2004
    Location
    Milwaukee, Wi
    Shooter
    35mm
    Posts
    3,242
    I have purchased items from Laabs also.

    Who would lie about being in Milwaukee?
    Claire (Ms Anne Thrope is in the darkroom)

  8. #8

    Join Date
    Sep 2002
    Location
    Willamette Valley, Oregon
    Shooter
    Medium Format
    Posts
    3,684
    Quote Originally Posted by Claire Senft View Post
    Thank you all.

    Here is a formula for a product similar to KRST.
    Water 500ml
    Ammonium Thiosulfate 50% Sol. 100ml
    Sodium Sulphide 30grams
    Sodium Selenide 4grams
    Water to make a liter.

    This formula was listed in May/June Photo Techniques magazine.
    It was supplied by Dr. Robert Chapman. If you are going to make
    this toner I advise wearing a dust mask. It is highly toxic thru
    inhalation and or of course ingesting it is also deadly.
    Similar to KRST? I don't see that. The results may be similar
    but that formula is far from. First it is the ide of selenium
    rather than the ite. Secondly is the inclusion of sodium
    sulfide and so much of it.

    As I recall a selenium toner may be composed of nothing
    more than some small amount of elemental selenium
    dissolved in a solution of sodium sulfite. Dan

  9. #9
    Photo Engineer's Avatar
    Join Date
    Apr 2005
    Location
    Rochester, NY
    Shooter
    Multi Format
    Posts
    22,972
    Images
    65
    There is a big difference between Na2S and Na2SO3 (IDE vs ITE) and Na2Se and Na2SeO3 (IDE vs ITE). The latter two are far more toxic of course, and the IDES are far less stable and more toxic than the ITES. Beware the IDES of Selenium and March both, or you can end up like big Julie with a pain in the portico.

    These chemicals will get to you right in the rotunda! Then you lose your hair and any gender associated attributes and it goes downhill after that.

    Beware of a garlic odor on your breath. By that time it is too late usually.

    PE

  10. #10

    Join Date
    Sep 2002
    Location
    Willamette Valley, Oregon
    Shooter
    Medium Format
    Posts
    3,684

    Google Groups rec.photo.darkroom

    Search rec.photo.darkroom for, sodium selenite .
    There a lot of information. Some very meaty.

    IIRC Kodak up untill a few years ago made available
    a toner blend of selenium and sulfide. A Kodak formula
    was made available via the WWW for those interested.

    Some one may correct me but I believe it was Kodak that
    added the RAPID, ammonium thiosulfte, to selenium toners.
    Also I've read it implied that the thiosulfate acts to make
    selenium a safer toner.

    I wonder if Sodium thiosulfate might not work just as
    well. That have been KSST. Dan

Page 1 of 2 12 LastLast


 

APUG PARTNERS EQUALLY FUNDING OUR COMMUNITY:



Contact Us  |  Support Us!  |  Advertise  |  Site Terms  |  Archive  —   Search  |  Mobile Device Access  |  RSS  |  Facebook  |  Linkedin