>From: "Phil" <phil1960us@...> >Reply-To: Homebrew_PCBs@yahoogroups.com >To: Homebrew_PCBs@yahoogroups.com >Subject: [Homebrew_PCBs] Re: Regenerating etchant?? >Date: Mon, 15 Nov 2004 03:01:27 -0000 > > > >--- In Homebrew_PCBs@yahoogroups.com, Adam Seychell <a_seychell@y...> >wrote: > > Thats not the full story, the regeneration reaction consumes both >oxygen > > (from air) and free hydrochloric acid. Overall it is; > > > > CuCl + O + 2HCl -> CuCl2 + H20 > >This doesn't balance. where does the other Cl go? > >But the reaosn for my post is a question about this process. I can >bubble for 48+ hrs and get slow etching ( about 1 hr) but if I add 50 >mL of 35% H2O2 (2.5 L of etchant) it takes about 1/3 the time. Acid >level look right and SG is getting towards 1.17. I think there must >be some other reaction taking place - any one able to shed light on this? Are you heating it? CuCl2 needs to be warm to work properly. Leon
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RE: [Homebrew_PCBs] Re: Regenerating etchant??
2004-11-15 by Leon Heller