You can always test it to see if there is ethanol in it or not, or you can also buy the stuff with the ethanol and remove it. Get yourself a junker freezer. Pour a measured amount of water into the gas. Put the mixture into the freezer. The water should absorb the ethanol. Remove ice from mixture. Measure amount after thawing.

It might be possible to not use the freezer, since gas is usually lighter than water, after mixing with amount of water allow to settle and drain off the water from the bottom.

I don't know if I would trust my skills after the experiment to use the gas or not but at least you will get an idea if there is ethanol and how much is in it.

This is all backyard science!