A chemist has recommended MEK. But I don't know where to get it or how to dispose of it after.

I guess I could just burn it, like I did the 15 gallons of bad gas. I put it in a 35 gallon drum and lit it. I was concerned it would light off with a big bang, but no. It sure did burn for hours though, and left a sludge on the bottom that won't burn. I even mixed some gas back in it, but the gas burned off leaving the sludge. I'll probably pour it in my waste oil. Before the EPA, such stuff made good weed killer.