I have seen other people post about making a “still” to clean the used IPA. So I tried it with a pressure cooker and a coil of copper pipe in a cooler for the condenser.
Well that attempt worked but was very slow. And if you used to much heat the IPA would boil and run dirty IPA into the condenser. It also was very slow and not be worth the time.
So I had an idea to use a vacuum pump to see if it would speed things up. First attempt I put the pump pulling the vapor from the pressure cooker. That made the pump get very hot so I moved the pump to pull from the condenser. That worked pretty good, still not fast but it may be worth it. What happens is pulling the vacuum keeps the IPA from boiling and it keeps all hoses and the pressure cooker lid tightly sealed. So basically you use a lot of heat on the pressure cooker and that speeds things up.
I did not measure the speed or timing yet but will do so next time. What was left over in the pressure cooker was a thick molasses. I had been doing clear and black resin. I need to find a way to clean that out of the pressure cooker.