Pulling ethanol out of gas

Another thing to consider when removing the ethanol from E10 gasoline (read Bruce Hamilton's 4 part Gasoline FAQ) is that ethanol is one of the higher octane components in unleaded gasoline. It has a blending MON (Motor Octane Number) of 102 and an RON (Research Octane Number) of 129. The CLC octane rating is 115.5. So if you manage to remove it you'll be left with gasoline that has a considerably lower octane rating than what you started with. (and less quantity of it too!)

Also, refineries can get away with initially refining lower octane fuel because eventually the final octane rating is BOOSTED when ethanol is added at the final distribution plant prior to shipment to the fueling station.

Chum lee