Bromoil bleach chemicals

Discussion in 'Alternative Processes' started by Paul Cocklin, Jun 6, 2009.

  1. Paul Cocklin

    Paul Cocklin Member

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    I've got a question on disposal of the bleach after creating the matrices. I've finally got everything assembled to start doing bromoil. Got the chemicals from B&S, got some amber bottles and got my ink and brushes.

    I just finished diluting the solids (Copper sulphate, etc) and putting the stock dilutions into the amber bottles. My question is, once I make my working solution, bleach 5 or 6 prints into matrices, what do I do with the working bleach solution? I find it hard to believe it's ok to dispose of it down the sink, as all three chemical warnings cautioned regarding corrosiveness and toxicity.

    Any suggestions? Also, how long is the working solution bleach good for? Is it reusable several days later if I bottle it? Any help is appreciated. Thanks!

    Paul
     
  2. nworth

    nworth Subscriber

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    The bleach usually used contains copper II and chromium VI. Both are quite poisonous, but the small quantities and great dilution in the sewage system generally make them innocuous. Copper sulfate is often used as a root inhibitor in sewage systems, and is generally tolerated well both chemically and legally. Some jurisdictions may be a bit more fussy about dichromates, which are classed as carcinogens. Most will allow disposal of small quantities, such as what you have, down the drain, but some may not. If you are one of the rare, unlucky ones, you can convert them into chromium III (like chrome oxide), which is safe.