Running rotovape in 45* ambient temps

Anyone have any tricks or tips or is it even possible to run a rotovap (5l) in 40-45*f ambient temps? If so, what are you putting over the water bath and flask to help keep temps where there supposed to be?

Would there be any issues of the etoh condensing before its hitting the condenser?

I’d rather not do a run in a spare bedroom with a fan blowing air outside.

You’ll be fine, get some of those ptfe plastic balls to keep the water from steaming everywhere.

Edit: Looks like there’s PP ones too, probably cheaper and just as effective.


I was looking for a cover of sorts like.on the fancy rotos and spd’s to go over the water bath.

Do you think ill have any condensing issues thru the vapor track from the work flask, thru the rotary motor to the condenser?

I’m not sure what you specifically call that area.

It won’t be much of an issue, should only slow down the recovery. That whole piece gets super hot as the hot vapor passes through it.


your all good, the vapor will heat the system.


I was gonna say…the system under enough vacuum should be fine. If anything, colder ambient temps makes the condenser not have to work as hard and will help condense solvent on the cold glass as well. This is a benefit, not a hinderance. Maybe consider using white mineral oil in your bath.


I have 2 gallons of glycol for my spd chiller I can use. Sweet, time to move back out in my 20x20 “tile room”, aka my lab.

I was afraid of cracking my condenser glass or uneven heating of the work flask as it spins .

Borosilicate glass can handle the temp differences, it is built for it. Hell, its continually below freezing outside here right now. I had a fantasy of filling a tank outside with glycol, on the north face of a building where the winter sun never shines, and pumping it in and out for a continual subzero bath.

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Use oil instead of water


Use duratherm s, or something that has a bery degradation problem,and if you want you can deacrb and volitales strip right in your roto

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