Red hot header pipe

a friend told me that if you buy a 5 gal beer/wine making glass jug and fill it with gas, if you let it sit awhile- the ethanol will seperate and you can just syphon out the crap and have good straight gas. Havent tried this yet, but it sounds feasible. He said it didnt sit long- just a week or 2, maybe 3. Cant remember.
I will ask the list to see if others tried that. I will prob get alot of snake oil comments, but we will see lol.