--- In
Homebrew_PCBs@yahoogroups.com, "Stefan Trethan"
<stefan_trethan@...> wrote:
>
> On Fri, 30 Jun 2006 14:54:28 +0200, Robert Hedan
> <robert.hedan@...> wrote:
>
> >
> > I've once gotten a dose of ammonia (fridge) and another of
chlorine (from
> > the pool) and never want to breath toxic fumes like that, ever. I
think
> > each one cost me 5 years of my life each.
> > I'm wary of mixing chemicals, so I'm taking the time to gather as much
> > information on this process first. I'd even go so far as
scrapping this
> > FeCl and buying another gallon before screwing this up.
> > Robert
> > :)
>
>
> I would prefer to start with a "clean" CuCl batch anyway, what reason
> would one have to keep that horrible "stain in a bottle" in it? I mean
> does the FeCl actually do any good? Also you won't be able to see
etching
> progress with it, normal CuCl is transparent enough if you place a
lamp
> behind the board (i found a small fluorescent light like sold for car
> repair works well).
>
> Regenerating CuCl is fairly safe. I mean the HCl is dangerous, sure,
but
> nothing like chlorine gas. Just wear adequate protection and have the
> proper respect towards the chemicals and you will be fine.
>
> ST
Over the years, I've wondered about regenerating Ferric Chloride,
too. One approach I've tied is reverse electroplating the Copper
(from the Copper Chloride) out of the solution, replacing it with
Iron. It seems to work, in that I definitely produced Copper on
on the cathode, while the Iron anode was dissolved (Actually, my
current density was a bit high, so I produced crystals of metallic
Copper on the cathode). Of course, one concern is that you don't
produce Chlorine gas (and, if you do, you want to make VERY sure
you don't breathe it!).
I don't remember how the resulting solution worked (It's been quite
a number of years ago.), although my main idea at the time was
removing the Copper from the spent solution (since dissolved Copper
compounds are lethal to most biological life forms).
Anyway, I don't know that I'd recommend this to anyone, but it may
be something to think about (especially if there are any
electrochemists in the group).
Dave