Distillation removes most byproducts but not enough to really matter. Their boiling points aren’t different enough and like with ethanol, distillation concentrates the bad stuff. It depends on the fermentation source but even vodka becomes significantly more drinkable when properly filtered.
18% requires a lot of tricks if you’re going the classical EC1118 route* but you can easily get 20% in a week or two from just turbo yeast (although its nigh undrinkable). I haven’t seen many reliable reports of 30% but plenty of 24-26%.
Distillation removes most _kinds_ of byproducts, but leaves some kinds nearly untouched. Eg no sugars come over, but unless really careful you get all kinds of weird other alkanols, like methanol, and other volatile crap.
Filtering can remove that crap, yes.
I didn't know that there are yeasts that are so much more alcohol tolerant. Interesting.
18% requires a lot of tricks if you’re going the classical EC1118 route* but you can easily get 20% in a week or two from just turbo yeast (although its nigh undrinkable). I haven’t seen many reliable reports of 30% but plenty of 24-26%.
* which IIRC is capable of 21% en extremis