They do let copper salts go into the environment at times. Someone
found copper chloride firebox cleaning sticks, and copper sulphate was
(is?) used as pesticide. Fireworks also use metal salts for color. I
think copper sulphate is even naturally occuring as a mineral.
So it's not a crazy "you will kill us all" kind of hazard, but it will
damage wastewater treatment bacteria in significant quantities so you
shouldn't just dump it down the drain. Evaporating sounds like a good
idea, especially since copper sulphate is useful for plating and such.
A while ago someone also suggested mixing it with cement into concrete.
ST
On Mon, Dec 7, 2009 at 6:21 AM, Piers Goodhew <piers@...> wrote:
> 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.htm
>
> When 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]
>
>
>
> ------------------------------------
>
> Be sure to visit the group home and check for new Links, Files, and Photos:
> http://groups.yahoo.com/group/Homebrew_PCBsYahoo! Groups Links
>
>
>
>