The thing about making alcohol fuels is that they need to be close to pure ethanol. A gallon of wash may net you a quart of 100 proof. Run it through again and that quart turns into a half quart or less of 140 proof. Run that through again and you may get a pint of 180 proof. 180 still has 10% water and other stuff that may not burn. See where I am going here. Ethanol plants or vodka distilleries produce 190+ proof but do it with a column still which for a home fuel maker is very expensive.