Which is safer to work with, AR or Hcl+peroxide?

[Subzero_01]

Hello friends,
I have been successfully working with very dilute AR solution for quite some time now when stripping gold from pcb's.
Now I wonder if peroxide method would be better, safer, faster?
Have 30% peroxide available and nitric as well, so thats not the problem.
I work in the open with full face high end breathing protection and small fan to push fumes away.
So what would community recommend?

 

[butcher]

Do some research in the cupric chloride leaching or etching process, often wrongly called the AP or acid peroxide process on the forum, where we form cupric chloride CuCl2 (using HCl and 3% H2O2 or air bubbled into the acidic solution) to dissolve copper and base metals into solutions normally leaving gold (the process is not fast but it is very efficient) for recovery of gold.

The copper chloride can be used and reused, or rejuvenated, over and over, with small additions of acid and air or oxygen.

For dissolving fine gold, you can look into using HCl and more concentrated peroxide to form chlorine in solution (does not form copious amounts of salts, or affect pH to a great deal), or the HCl and sodium hypochlorites (bleach) to dissolve gold which does form more salts and does drastically affect the pH.

 

[Jado]

Agree with Butcher 100% on Cupric Chloride method. To directly answer your Qs…
Better) Yes and No.
Safer) Negligible vs cold AP, Hard yes vs hot AP, scrubber is a fairly easy DIY for Cl gas vs NOx.
Faster) Definitely not.

The big thing is what you’re confident using.