Roto vape

is There anything better to use for a roto other then water? I’m finding I’m constantly adding more water. Does anyone have any input at all? All comments good and bad are appreciated.

I don’t understand the question, also title should read" rotovap" or “rotery evaporator”. The vapeing is best left to the pros!:stuck_out_tongue_winking_eye:


Lol I’m calling for all pros to help this little guy become part of the elite.

Raise the solution temperature before it hits the roto and lower the bath water. Anything over 50C is going to evap water rather quickly.

Ok thanks. Is water the best solution to use in the roto bath? Also what do you think for the chiller solution?

Water works fine. I use Cryo-tek 100. Cheap and effective.

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You can use a hydroponics style chiller running glycol. I use a chill king for my “chain gang” of rotary evaporators.

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I appreciate all the input

Add ping pong balls to the bath, this will greatly reduce evaporation.

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I use oil. It doesnt evaporate at all so I rarely have to add any.

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I don’t like the nasty films that from oil baths, it could also be a possible source of cross contamination.

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It has not been an issue for me yet. Tests are still coming out clean but I may need to keep an eye out for that.

@Sidco_Cat has some pretty cool aluminum ingots at a show that I believe were for replacing the water in your bath

Dry baths? Can’t be used in a roto. Any wobble in the flask you risk breakage.

No these were closer to sand, but larger partical size. Little bits of aluminum

My understanding is that you are having issues with your water bath for your roto evaporating too quickly.

Use mineral or silicone oil instead of water.

Or work to use a stronger vacuum so your solvent you are trying to boil off will be removed at lower temperatures.

I guess in true italian nature you could add sodium chloride which will very slightly raise the boiling point. Cooks your pasta faster :open_mouth:


Yeah like bb’s? I’ve seen people use them an alternative to sand baths. When you said ingot a large peice of metal came to mind. Be carefull lowering your roto with bb’s, I could see a broken vapor duct from the stress of trying to displace all that material.

HI , what is the ratio to mix for Cryo-tek ? Do You mix with distilled water ? Thanks