Tetrahydrofuran Azeotrope?

Hello everyone!

I got some pvc primer from DoIt, and the container says it contains acetone, THF, MEK, and cyclohexanone. I am fractionally distilling it as we speak.

I slowly heated it until the thermometer at the top read 56 C, the boiling point of acetone. It stayed constant for a long time, then the drops ceased so I cranked up the temperature. As we speak, the still's temp reads 63 C, and a BUNCH of liquid is coming out. I thought it is THF... but then I tested it for a ketone by adding NaOH and iodine, and CHI3 formed ... Does THF form an azeotrope with anything else? THere is no contaminates that I can think of! Why is there a ketone there?

By the way, is there a way to qualitatively test for THF?

Thanks,
SciHide

P.S. I am distilling over ferrous sulfate to avoid peroxides