Sciencemadness Discussion Board

strange extraction

soma - 8-1-2016 at 02:48

I was doing an extraction using hexane and basic water. I refluxed the solution slightly 1st and then let it cool til it wasn't boiling. Then I shook the solution.

When I went to vent it, it suddenly foamed up and sprayed out of the flask.

After trying a few more times I found that if I waited for a bit before venting, it wouldn't foam up. But if I vented it immediately, it would foam.

Anyone explain what happened?

Thanks.

SunriseSunset - 8-1-2016 at 04:56

I would just guess that because you didn't wait for it to cool down to room temperature, and there were still elevated temperatures, perhaps since the water held more heat energy and the phases mixed again, you boiled the hexane again. Seems about right. Especially since it didn't foam up until you released the pressure.

[Edited on 8-1-2016 by SunriseSunset]