Chemist514 - 6-5-2007 at 12:04
Just a quick question to the chemically inclined masses.
After evaporating 2 litres or so of water out of a large batch of HCL/H2O2 copper etchant I was left with fine green crystals, and alot of HCL, then a
stainless steel spatula fell into it. *GROAN* In any case there is now a trail of black through the dish and it's obviously been contaminated with
iron maybe chromium but i thought that was hard to disolve in HCL.
Can I just recrystalize the batch and take out less crystals from the batch? Or is the iron going to have to be removed first? ill proly scrap the
batch in that case cause with no noticable damage to the spatula there cant be much to take out.
Hope everyones projects are going well, all the best!
woelen - 6-5-2007 at 12:58
I would try to take out the black trail as much as possible and for the rest I would recrystallize from distilled water (also good for getting rid of
excess HCl from the CuCl2.2H2O). I would not really worry about the trace impurity, which remains after this treatment.
12AX7 - 6-5-2007 at 15:09
Don't forget about the nickel, too.
Might be able to recrystallize it. Nickel and Fe(II) might be hard to remove, and in my experience, Cr(III) is a bitch to remove from solution
(deliquescent).
If nothing else, you can cementate the copper out with say, iron metal, and burn it back to copper chloride later.
Tim