If you "revigorate" it with a slug of HCl after etching a board or two, over time the Fe will oxidise and settle as insoluble FeO. Then just decant it. That's how I quite unintentionally converted from FeCl to CuCl. Didn't dawn on me until I started looking at the chemistries involved.
--- On Sat, 6/28/08, Leon <leon355@...> wrote:
From: Leon <leon355@...>
Subject: Re: [Homebrew_PCBs] Ferric Chloride - Alternatives
To: Homebrew_PCBs@yahoogroups.com
Date: Saturday, June 28, 2008, 3:02 PM
----- Original Message -----
From: "Stefan Trethan" <stefan_trethan@ gmx.at>
To: <Homebrew_PCBs@ yahoogroups. com>
Sent: Saturday, June 28, 2008 6:59 PM
Subject: Re: [Homebrew_PCBs] Ferric Chloride - Alternatives
> Yes, but doesn't that just produce CuCl contaminated with dirty FeCl
> (AKA "Stain from Hell")?
Yes, but they are both etchants, so the regeneration works. Do it for long
enough and the FeCl3 will gradually disappear. 8-)
Leon
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