Using that "phase separation" method is also a way to make non-ethanol gas from ethanol gas. The result is allegedly about 2 pump octane numbers lower than the base fuel. Ethanol is an octane enhancer.
Rather than a graduated cylinder, a calibrated fruit jar would work, too. Easier to find, just that you generally have to get six or twelve at a time.
Starting with the base leaded gasoline of prior times, it allegedly takes 5% more crude to make unleaded fuel than leaded fuel. Guess how much shortfall there was on the first energy crisis? 5%. No loss in energy level, though.
The first ReFormulatedFuel (RFG) was supposed, according to Chevron (who had a very extensive "back part" of their website devoted to such, back in the '90s) result in about l3.5% less fuel economy, which I was able to document on the car I was driving at the time (1970 Skylark 350 2bbl, CA emissions). Later E10 is supposed to yield about 6% less fuel economy than E0.
The Ethanol Lobby has now got E15 approved for year round sale, rather than just "smog season". They claim it makes newer cars run better and more economically, but with adaptive engine controls and ONE more octane number above E10, I'd like to see their significant data on that! Locally, it's 5cents gallon less money than E10 (at the same station). One survey they touted claimed that consumers wanted E15 (about 60% of whom didn't know what it was, just that it was less expensive with allegedly better performance and mpg, so what's not to like?).
So, consider ethanol to be a "fuel extended" for normal gasoline, rather than a "cleaner burning" fuel (any data to prove that?) per se. Biobutanol is related to ethanol, can be produced in converted ethanol facilities, with NONE of the issues of ethanol. BB at 16.5% yields better emissions than E10, with NONE of the downside issues of E10. And it's been approved by the EPA for use in motor fuel for years!
Some state legislatures put the use of ethanol into their state laws a while back, to that's all that can be added in those particular states . . . unless the laws change (no chance of that, any time soon, I suspect).
The interesting thing is that when they remodeled the WalMart fuel stations (Murphy USA oil company supplied), they added non-ethanol fuel into their product offerings. About 30cents/gallon more, though. There are supposed to be some private brands of fuel in the southern Midwest which sell a full selection of octanes in ethanol-free fuel. One of the ethanol-free gasoline websites had a state by state listing of ethanol free fuel availability, most of which are usually private-brand fuels near marinas, at 87 octane or there abouts. Not sure how up-to-date their listings are.
Just some thoughts,
CBODY67