You left out pressure-swing distillation which doesn't require any "fun" substances to break the azeotrope. I'm not sure if it's used commercially for ethanol t

You left out pressure-swing distillation which doesn't require any "fun" substances to break the azeotrope. I'm not sure if it's used commercially for ethanol though? I believe it's more expensive. Also the really high purity stuff (for HPLC and the like) has the "fun" chemicals removed from it and a chemical analysis printed on the side of the jug. Benzene content can be well below safe drinking water standards depending on the product. Pretty sure you'd be paying more at that point than just buying taxed vodka though.