Homebrew PCBs

I am following up on a comment in an earlier thread, to the effect that starting with 2 parts drug store hydrogen peroxide + 1 part Muriatic acid, one cannot ever get to the point of having CuCl2. (BTW, please forgive & correct if I do not get the chemical formulas right. Chemistry was a LONG time ago!)

I am concerned / disappointed, because I have been saving my used etchant, made from the above, thinking that I would eventually build a tank to bubble in air to regenerate it, etc. But now it sounds like I would do better to neutralize what I have and start over.

1) Is that right, or is there any way to use the used etchant I now have on hand?

2) What do I need to do to make up an etchant mix that WOULD serve as the base for CuCl2?

Many thanks ...

Andy