i soaked PCB in hcl solution for 2 month, suddenly when i mixed with h2o2 there is a brown bubble coming out and the solution turns into brown, what
chemical is this ( the PCB i used mostly from clf lamp)macckone - 21-1-2019 at 21:28
Copper is rather inert to HCl, however peroxide will make it much more reactive.
After 2 months you finally started to dissolve the copper.
However you will also dissolve other things that will not be as soluble.
Silver and lead have a small solubility and are usually considered insoluble
but they are soluble enough to separate from the pcb board under these conditions.
copper chloride complexes and be red, yellow or blue depending on the primary state.
They can also be a mixture which can give browns or greens.
The usual procedure is to add excess HCl and peroxide until the board is clean of copper.
Then filter to remove gunk, usually silver and lead.
Finally you plate the copper onto something.phlogiston - 22-1-2019 at 02:00
Oxygen/air also can help dissolve the copper, but it is slow unless you actively bubble air through the solution.
Seems like a very elaborate way to recover a very small amount of copper.fusso - 22-1-2019 at 07:14
