Possibly- I really don't know. But since Ethanol is close to the specs (volatility, etc.) of gasoline I don't see the point. Possibly a blend of 95% Ethanol/ 5% Biodiesel (for example) would raise the BTU value of the fuel while still allowing it to function in conventional spark igniiton engines, but I haven't tested this myself. Might be a good project for somebody with the time to tinker.
Actually, as mentioned on the thread, clean vegetable oil will function in a diesel engine without further refining- just don't let the car get chilly, as the vegetable oil will turn to goo and clog filters, fuel injectors, etc.
(Petroleum diesel does this also, just at much lower temperatures.)
I can imagine a future engine designed to run on a mixture of grain alcohol and vegetable oil.
As I recall, some early vehicles had special heated manifolds which allowed their spark-ignition engines to run on cheaper "distillate" (modern day diesel) after the engine was warm. The engines were started on gasoline from a smaller tank when cold.