[WardL]

E10 gasoline will consume water until it is totally saturated. The next drop of water (or condensation in the tank) will cause a phase separation where most of the water will drop down to the bottom of the tank. The ethanol will split between the gas and the water, but most of the ethanol will be in the water phase leaving about 4% of the ethanol in the gasoline phase. No engine will run on the water and the 4% ethanol gasoline probably has 85 octane. I don't know how a Fitch fuel catalyst could counter thermodynamics.