What to do with old gas/diesel?

[etpm]

My grandfather had a little discreet distilling business during the prohibition period. He always told me that to avoid making poisonous alcohol, to only use copper or glass for the distillation pot and tubes. He told me that the toxic alcohol (methanol) came about when people used tin or galvanized pots for distillation. IDK if he was correct, but that is something I remember him talking about.

He was incorrect. The methanol, along with other poisons, is a natural result of the fermentation process. During the distilling process different chemicals will boil off at different temperatures. First are the "Heads", then the good stuff which is the ethanol, then comes the "Tails". Good distillers can tell by the taste what is OK to drink. Even mediocre distillers can tell pretty close. Of course this is not exact, but it gets pretty close. Ethanol is not the only desired product unless vodka is being made. The flavors desired depend to a very large part on the skill of the distiller. Distillers will save the heads and tails to add to subsequent batches because of the inexactness of the process. I'm talking about small operations. There are several small distilleries close to me and I have done some machining and welding for a few distilleries. Because of my innate curiosity and the helpful nature of some nice folks I was shown and taught a lot about distilling. I even bought a couple books, one of them being authored by a fellow who was helping a new distillery get going. I got to taste the stuff straight from the still and learned a little about the stages of the product. Very informative and lots of fun.
Eric