metricp - 12-9-2024 at 02:44
Hello, Has anyone here tried regenerating, recycling or re-using piranha solution before? We go through quite a lot to dissolve cyclized polyisoprene
films and I'm trying to find a way that we could filter/dispose the dissolved polymer and reuse the piranha solution. I imagine the hydrogen peroxide
will just degrade and we'd need to add more, but if we could recover at least the sulphuric acid, this would be very useful.
Sulaiman - 12-9-2024 at 09:45
I imagine that the polymer will be entirely converted to CO2 and H2O by the piranha solution,
so concentration to about 70% w/w sulphuric acid could be easily recovered by boiling off water,
above 70% there will be lots of acid fumes,
but you could continue boiling until 95 to 98%,
but, the catalyst byproducts will accumulate if the acid is not distilled - which is possibly an option.
Please note disclaimer below 
Deathunter88 - 12-9-2024 at 22:26
Probably not worth the effort in an actual profession lab setting.