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Subject: Re: Persulfate etchants

From: Len Warner <novost@...>
Date: 2009-04-28

At 8:06 pm ((PDT)) Mon Apr 27, 2009, in Digest 2765 Simao Cardoso wrote:

>On Thu, 2009-04-16 at 14:25 +1000, Adam Seychell wrote:
> > Sodium and ammonium persulfates behave very similar,
> > and you cannot reuse either of them. [snip]
>
>[snip most of Simao's reply] but to
>end with all the doubts the etchant reaction is:
>Na2(SO4)2 + Cu+ --> Na2SO4 + CuSO4
>Or like this?
>Na2(SO4)2 + H20--> Na2SO4 + H2SO4 + H2O2
>H2O2 + H2SO4 + Cu --> CuSO4 + 2H2O
>basically both are right but the second ends with
>the speculation that fooled me right?

Please explain: what speculation? Also note that the
second of the three reactions is not balanced :-(


Regards, LenW