I have a flask of ferric chloride which was used to etch some copper -- and, inadvertently, some hardened steel. At this point, I believe the solution contains

 

[ce]FeCl3 + FeCl2 + CuCl2[/ce]

 

I'd like to salvage as much etchant as I can. Is there any way to

 

1. Remove the cupric chloride? Perhaps by converting it into something that isn't water-soluble and hence will precipitate out?
   
2. Oxidise the iron(II) chloride back to iron(III) chloride?
   

 

Thanks!

Cupric chloride is a fine etchant in it's own right. In fact, if you prepare an etching bath of it, and continue to add HCl, you can simply restore it by bubbling air through the mix. I believe that Ferric chloride may be restored the same way, but I'm not sure how readily the air oxidation proceeds.