Going back to at least 2020 on this forum, there have been various suggestions on how to extend the life of IPA. A few months ago, I purchased a 3-gal capacity stainless steel system made by Vevor and sold on Amazon. Just search for “Vevor still 3 gallon” to find options. Mine included the thumper only because that system included a submersible pump I used to circulate cold water thru the cooling pot. This is the same system used by home-distillers and folks who make custom aromatics (that’s where the thumper is used but isn’t needed for IPA).
This equipment paid for itself in 3 cycles compared to buying fresh 99% IPA at $17/gal. It’s efficient (about 80-83% reusable IPA from a 3-gallon batch), quick (about 3 hours), and environmentally friendly. Residue after distillation is scraped out of the pot and spread on cardboard outside where sunlight cures the sludge making it inert and “garbage friendly”. The jugs containing fresh IPA are refilled with clean, clear IPA, 1 gallon at a time. There is no “life expectancy” on recycled IPA … just keep running the dirty stuff thru the system, do a clean out, and keep going. No more messing with disposing of IPA that’s “only” 10% saturated with resin!