Sciencemadness Discussion Board

5+ liter vacuum distillation

lancer3000 - 4-5-2013 at 20:54

Good evening SM.

I had a couple questions and concerns regarding larger scale vacuum distillations. I would like to run through my plans and ask for a inspection on said topic.

Normally I have done vacuum distillations in the 1000 to 2000ml range. I would like to step it up to 5 Liters.

1. Use a heating mantle/ stirrer combo all in one unit. There are some from China that are reasonable, but the questionable part is the stirrer function. I have had trouble stirring even the 2 liters with a stirplate/oil or sand bath. Going to 5L I am only imagining what a import mantle/stirrer could possible due.
2. At this scale, is introducing a gas inlet tube or capillary tube to induce a type of stirring more advisable, instead of the magnetic stir bar?
3. Is running a 5L RBF under vacuum a larger risk, due to the larger surface area/stress on the glass? Is a plexiglass shield necessary?
4. Is 24/40 joints still a suitable size?

I believe these are the main questions I have, but if anyone has tips on a vacuum distillation of this size then please let me know. I am quite experienced with vacuum distillations at the smaller scale, so general procedure is a no brainer, just scaling up brings a couple worries that may be easily quelled.


CaliusOptimus - 5-5-2013 at 21:23

The answers to your questions depend entirely on what it is that you plan to distill.

What temp?
How much vacuum?
How viscous?
How likely to super heat?