BZT mixing

Discussion in 'B&W: Film, Paper, Chemistry' started by Colin Graham, Jul 16, 2005.

  1. Colin Graham

    Colin Graham Member

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    I've been trying to mix a simple 2% solution of benzotriazole and keep getting a needle/crystalline precipitate when mixed with 125 degree water. Better to use cold water or could the chemical be off somehow? Hate to keep wasting it. Thanks for any help.
     
  2. Peter Schrager

    Peter Schrager Subscriber

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    Benzo

    You need to first mix it up with about 200ml of iso-propyl alcohol. Than bring it to the needed quantity. It will stay suspended in this solution indefinately.
    Peter Schrager
     
  3. David A. Goldfarb

    David A. Goldfarb Moderator Staff Member Moderator

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    It doesn't dissolve easily in water. Mix a 1% solution and use twice as much, which is what I do, or dissolve in something like alcohol.
     
  4. Colin Graham

    Colin Graham Member

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    Great! Thanks very much.
     
  5. Ian Grant

    Ian Grant Subscriber

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    The normal way to make up a 2% Benzotriazole solution is:

    2% Benzotriazole / 10% Sodium Carbonate solution (Ilford IBT)
    Kodak's version was 3% Benzotriazole with sodiun Sulhite.

    Benzotriazole will dissolve easily in water above 52°C

    Ian
     
  6. David A. Goldfarb

    David A. Goldfarb Moderator Staff Member Moderator

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    Edwal Liquid Orthazite is also 3% with sulfite.