Water quality question - distilled, "ozonized" etc

Discussion in 'B&W: Film, Paper, Chemistry' started by Michael R 1974, Mar 20, 2013.

  1. Michael R 1974

    Michael R 1974 Subscriber

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    The other day at the supermarket I noticed a type of water that reads "equivalent to distilled". What does that mean? Is it just demineralized by a different process?

    Also, what is the deal when it says "Ozonized"? Is that just a process to kill microbes before bottling? Or is there actually dissolved Ozone in the water? My understanding is solubility of Ozone in water is low.
     
  2. Fred Aspen

    Fred Aspen Member

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    Excellent question, Michael. I also have questions about the "Ozonated" process that is indicated on my supplies of distilled water. It does state it is purified by steam distillation, filtered and ozonated. I have always wondered if the ozonation process has anything to do with the fact I can never get Xtol to last more than a few weeks before going flat, even though I store in Boston rounds sealed with Saran wrap. Hope someone can address this issue.

    I did find this online:

    "Ozone disinfection
    Ozone is a very strong oxidation medium, with a remarkably short life span. It consists of oxygen molecules with an extra O-atom, to form O3. When ozone comes in contact with odour, bacteria or viruses the extra O-atom breaks them down directly, by means of oxidation. The third O-atom of the ozone molecules is than lost and only oxygen will remain.


    Read more: http://www.lenntech.com/products/chemicals/water-treatment-chemicals.htm#ixzz2O5sbcQnt"

    Since oxidation is a primary killer of developer, is this perhaps what is zapping my Xtol? Is the Purified Water perhaps a better choice? I will check at the market and see which bottled water products are ozonated today.

    Apparently the half life of ozone (O3) is about 20 minutes but when that time has elapsed, O3 breaks down into O2. It is my assumption that this is in the form of dissolved oxygen. If so, not good for developer.
     
    Last edited by a moderator: Mar 20, 2013
  3. Gerald C Koch

    Gerald C Koch Member

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    Hi Michael,

    By equivalent to distilled I would assume that it is purified by reverse osmosis. Ozone is so unstable that it is not going to be present when the water bottles reach the store. The main problem with ascorbate developers is with Fenton oxidation not aerial oxidation. Fenton oxidfation is catalysed by iron and copper present in the water.

    Jerry
     
  4. Michael R 1974

    Michael R 1974 Subscriber

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    Thanks, Gerald. That's what I expected but wasn't sure. I noticed this particular type of water is half the price of the normal distilled water I buy so I was wondering if there was something materially different about it.