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Subject: Re: [Homebrew_PCBs] Disposing of Chemicals

From: Adam Seychell <a_seychell@...>
Date: 2007-04-16

pcb.easy wrote:
> Am I on the right track?
> Can the sludge be reduced even more by drying?
> If so how can it be safely dried?

You are doing conventional heavy metal waste treatment by precipitation
of metal hydroxides. For such small quantities you best off drying the
sludge in a open tray and put the powder in a plastic or jar and then
into the rubbish bin. This is more moral than dumping in the sewage
system. I find builders lime (non pure calcium hydroxide) as a better
etchant neutralizer as the resulting sludge is more solid and compact.

I have about 10kg of copper hydroxide accumulated of over the years :(