Chemical Disposal

Thesrot · Post by **Thesrot** » Fri Sep 19, 2008 6:35 am

The rules for photographic chemical disposal in Seattle appear to state that you can pour pretty much anything down the drain except silver. It stated therefore that fixer and bleach should be taken to a disposal facility. I don't use fixer for my holography but I of course use bleach. Does the used rehalogenating bleach we use in holography contain silver such that I need to not pour it down the drain?

Thanks.

Martin · Post by **Martin** » Fri Sep 19, 2008 7:01 am

Thesrot wrote:The rules for photographic chemical disposal in Seattle appear to state that you can pour pretty much anything down the drain except silver. It stated therefore that fixer and bleach should be taken to a disposal facility. I don't use fixer for my holography but I of course use bleach. Does the used rehalogenating bleach we use in holography contain silver such that I need to not pour it down the drain?

Thanks.

My guess would be that in contrast to reversal bleaches rehalogenated don't contain high amounts of silver.
On the other hand, I don't know any rehalogenating bleach – put aside some special peroxide formulas – I would feel comfortable pourring down the drain.

Thesrot · Post by **Thesrot** » Fri Sep 19, 2008 8:14 am

Thanks. I'll be using:

35 g Copper Sulfate
10 ml Glacial Acetic Acid
110 g Potassium Bromide
One liter of Water

I'm doing the JD-3 / Acetic acid system which I believe ends up as listed above. Would like to follow proper disposal procedures but no holo section in my local water rules...

Tom B. · Post by **Tom B.** » Sat Sep 20, 2008 6:09 am

The rules for photographic chemical disposal in Seattle appear to state that you can pour pretty much anything down the drain except silver. It stated therefore that fixer and bleach should be taken to a disposal facility. I don't use fixer for my holography but I of course use bleach. Does the used rehalogenating bleach we use in holography contain silver such that I need to not pour it down the drain?

A rehalogenating bleach does not dissolve the developed silver, but instead converts it back to silver bromide which can migrate a little bit within the emulsion but does not end up in the bleach to any appreciable extent. I've noticed that these bleaches keep well and can be re-used for a very long time with good results, so you don't need to flush after only one use.