I've wondered about this, too, and I've read a few things "somewhere" - i.e.
I can't actually swear they're true, but they seem to add up:
Ammonium Persulphate as-is is a mild fertiliser without much toxicity. Once
copper is dissolved in it, we get Copper Sulphate which is a little more
toxic. This should be evaporated and disposed of in your local hazardous
waste facility - you evaporate because at "non-hobby" quantities, you pay by
weight. However, CuSO4 is also commonly used as a pool fungicide
(algicide?), so folks with pools often just throw it in there - i.e. it's
not that toxic to humans.
Now, the following I do have evidence for:
Looks like the original poster is in Australia, as I am. At least in NSW you
can dispose of "hobby chemicals" for free on special days which rotate
around the local councils:
http://www.environment.nsw.gov.au/households/CleanoutGuide.htmWhen I eventually turn all of my jar of Ammonium Persulphate into blue salt,
that's where I'll be heading, but it will be years!
PG
On Mon, Dec 7, 2009 at 1:34 PM, <tim.wade@...> wrote:
>
>
> Read somewhere - can't find it now of course - that you should let it
> evaporate so that you effectively end up with copper sulphate crystals
> then place sealed bottle and put in the rubbish...
>
> From: Homebrew_PCBs@yahoogroups.com <Homebrew_PCBs%40yahoogroups.com>
> [mailto:Homebrew_PCBs@yahoogroups.com <Homebrew_PCBs%40yahoogroups.com>]
> On Behalf Of Stefan Trethan
> Sent: Monday, 7 December 2009 1:11 AM
>
> To: Homebrew_PCBs@yahoogroups.com <Homebrew_PCBs%40yahoogroups.com>
> Subject: Re: [Homebrew_PCBs] Ammonium Persulfate - poisonous?
>
>
> On it's own it's Xn rating, no idea what it would be with the copper.
> Anyway Xn is enough that you want to read the MSDS.
>
> <http://www.hillbrothers.com/msds/pdf/n/ammonium-persulfate.pdf>
>
> Which is not too bad, seems it's just barely Xn.
>
> Once you add the copper, you are not supposed to flush it down the
> drain anyway, so it doesn't really matter if AP could be disposed of
> that way. Bring it to your local waste disposal facility, in most
> places around the world household hazardous waste can be brought in
> free of charge, to discourage people dumping it illegally.
>
> ST
>
> On Sun, Dec 6, 2009 at 3:54 PM, Anthony Shipman <als@...<als%40iinet.net.au>
> <mailto:als%40iinet.net.au <als%2540iinet.net.au>> > wrote:
> > On Sun, 6 Dec 2009 06:45:22 am designer_craig wrote:
> >> I am not sure if you mean Ammonium Peroxide or Ammonium Persulfate
> but I
> >> had some quantity of the latter sitting around for 15 years and it
> all went
> >> bad and would not etch anything when I tried to etch a board. Not
> sure
> >> what it decomposed to but I suspect it reverted to Ammonium Sulphate.
> >>
> >> Craig
> >
> > BTW how toxic is this stuff (Ammonium Persulfate). The container had
> no
> > warnings on it. I have some etchant with dissolved copper in it. Is it
> > poisonous? What is the best way to dispose of it?
> >
> > --
> > Anthony Shipman Mamas don't let your babies
> > als@... <als%40iinet.net.au> <mailto:als%40iinet.net.au<als%2540iinet.net.au>>
> grow
>
> up to be outsourced.
> >
> >
> > ------------------------------------
> >
> > Be sure to visit the group home and check for new Links, Files, and
> Photos:
> > http://groups.yahoo.com/group/Homebrew_PCBsYahoo! Groups Links
> >
> >
> >
> >
>
> [Non-text portions of this message have been removed]
>
>
>
[Non-text portions of this message have been removed]