You don't need to add more copper. The dark green is cuprous chloride.
Add more H2O2 or bubble air through it to convert it to cupric chloride.
It will turn a lighter green as it converts. You may need to add acid if
it doesn't etch very well. IME bubbling air through it takes quite a
long time. You need fine air bubbles like you get from an air stone but
air stones disintegrate in the acid.
Les
Howard wrote:
> Hi
> I have been doing etching with HCI (Spirits of salt 32%)
> and H202 (6%) in a mix of 1 part HCI to 1 part H202, in small
> amounts (.5ltr), after etching i then put the acid into a 3ltr
> bottle, now the bottle is full of medium to dark green stuff!
>
> So now i would like to make use of it to make CuCI.
> Now i think that i need to add some copper to the mix and pump
> some air in.
>
> I have a Mega-UK type of tank with a built in air pump and heater
> it holds about 5ltrs. Could i just put the 3ltrs of used mix into
> the tank, add some copper(how much?) and turn on the air(how long for?)
>
> When will i know when it is converted to CuCI ?
>
> Hope that someone can put me right on this
>
> Regards
> Howard
>