[sdiy] PCB etching and safety

[Neil Johnson]

> > > Don't pour the spent Ferric Chl down the drain, it will melt your
> > > pipes.
> So ... what *do* you do with it?
>
> I've heard of mixing it into some concrete, but I think it could still
> leach out over time.

One thing mentioned on the site I posted earlier:

"At this stage the solution is exhausted and requires disposal. This can
be effected by the slow addition of either calcium carbonate (whiting) or
sodium carbonate (washing soda crystals) - until effervescence ceases. At
this point the solution is neutralised and may be disposed of safely."

Sounds like a practical answer.

Hope this helps,
Neil

--
Neil Johnson :: Computer Laboratory :: University of Cambridge ::
http://www.njohnson.co.uk          http://www.cl.cam.ac.uk/~nej22
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