Potassium Iodide question of longevity.

Discussion in 'B&W: Film, Paper, Chemistry' started by bobbysandstrom, Oct 12, 2005.

  1. bobbysandstrom

    bobbysandstrom Member

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    I'm making a .001% solution of potassium Iodide for use with the FX-1 developer. Does anyone know how long this dilute solution will last? I bought enough chemicals to make (4) 1-gallon kits. The recipe calls for very little amounts of the potassium Iodide. I will make 1 gallon worth of the developer and I would like to store the diluted Pot Iod solution to be used with each successive 1-gallon kit as I require more developer.

    thank you
    bob
     
  2. john_s

    john_s Subscriber

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  3. Alan Johnson

    Alan Johnson Subscriber

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    In the original article about FX-1 ,BJP Jan27 1961,G.W.Crawley suggested making progressively more dilute solutions including 0.1% , 0.01% and 0.001% potassium iodide using water boiled for 3 min and cooled to about 90F.

    Make future supplies from the 0.1% and the 0.01%. He said these solutions should keep indefinitely but reject the 0.001% after 2 years.