--- In
Homebrew_PCBs@yahoogroups.com, Adam Seychell
<adam_seychell@y...> wrote:
...
> If you want to remove copper then easiest approach is throw in some
scrap
> iron and/or aluminum while the etchant is still slightly acidic. The
copper
> precipitates as copper metal and aluminium/iron goes into solution.
> After about 1 week the solution will be crystal clear with brown copper
> sludge on the bottom. Syphon out most of the liquid being careful
not to
> disturb the sediment, neutralize the remaining sludge and leave few
days to
> dry to a dark crust. Works well with spent ammonium persulfate
etchant and
> CuCl. But I havn't tried treating FeCl3 etchant this way.
Adam, would you post this in the Files section, in the Acid Etching
folder?
This is great info. I'm very uncomfortable just dumping this stuff,
not etched very many boards so mostly I just dumped baking soda into
FeCl (yuck) let it dry and put it in the trash.
BTW, if anyone near Tacoma, WA wants a bunch of dry FeCl, I have
several pounds to get rid of. Give me a couple of chunks of PCB and
they are yours. I'm going to try making some CuCl.
Steve