On 28/11/11 10:19, DaveC wrote:
> OK, everybody, chime in here and share how you dispose of your etchant.
>
> I've got metal pipes so need to know what to do.
>
> But then again, with my weak concentration, maybe I've got nothing to
> worry about...
I've been using the same FeCl in a tank for the last 2+ years and top it up with
hardware-shop muratic acid (HCl). It's probably converted to CuCl etchant now.
FeCl is a flocculating agent for sewer treatment. With dissolved copper from
etching, it is highly toxic to plants and makes an ∗excellent∗ weed killer.