subsecret - 1-12-2013 at 11:35
Yesterday, I distilled about 250 mL of dichloromethane from Crown Handi-Strip paint stripper.
--Let me give you some background:
About a week ago, I bought a rubber stopper so I could distill the DCM straight from the can. While I was test-fitting the stopper into the can, it
fused to the rim (likely) because of the DCM. I went at it with needle-nose pliers, but it fell in. The stopper dissolved, giving the paint stripper a
yellow-orange tint.
The contaminated paint stripper was placed in a flask, and a distillation apparatus was constructed. The DCM distilled for about 3 hours at 40-45 C,
and I added several more volumes of paint stripper to the flask through the course of the distillation. It proceeded at a fast drip rate, about 2
drops per second.
After I collected about 200 mL of clean DCM, I turned off the heat source (a steam bath, in this case). I let the apparatus cool down some, and then I
poured some water into the still pot to cool it completely. As the water hit the yellow-orange liquid in the still pot, an emulsion or suspension (I
suspect) formed, taking a milky yellow color. Luckily, the DCM that distilled was clear and seemed to be clean. A second distillation may be conducted
in the future.
What could the milky emulsion be?
Any help is greatly appreciated.
DJF90 - 1-12-2013 at 12:04
It'll be all the shit in the paint stripper that isn't as volatile as DCM.
I'd dry and re-distill your DCM, collecting only what passes at 39-40 *C.
subsecret - 1-12-2013 at 13:01
Thank you.