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Chemistry Forums for Students => Undergraduate General Chemistry Forum => Topic started by: Rick on April 12, 2018, 10:59:36 AM

Title: Removal of solvent using rot evap
Post by: Rick on April 12, 2018, 10:59:36 AM
If I am writing the experimental section of a report and use a rotary evaporator to remove a solvent from a liquid phase to afford a solid product is it more correct to say "The solvent was then removed using a rotary evaporator" or "The product was then concentrated in vacuo"?
Title: Re: Removal of solvent using rot evap
Post by: P on April 12, 2018, 11:43:10 AM
Personally I think the first one sounds better.  You could phrase that same sentence many many ways.

How about - "The product was collected via a rotary evaporator"  or, "the solvent was driven off via rotary evaporation"... or "the product was purified via rotary evaporation"  etc....  something like that.

It's up to you and both of your suggestions are technically correct imo, but the first one seems to flow better in my mind.
Title: Re: Removal of solvent using rot evap
Post by: wildfyr on April 12, 2018, 01:48:49 PM
Both are perfectly clear and correct, however I would consider the first one to be more modern and precise. *in vacuo* can also just mean simple distilled off using a shlenk line using house vac.

Typically I would remove 99% of the solvent with a rotovap, then hi-vac it on my line for some time between 20 minutes and a 24 hours depending on the material (polymers need more time).

If you did the same, then perhaps say "The majority of the solvent was removed by rotary evaporator, then the material was subjected to high-vacuum overnight on a shlenk line." Its precise, simple to understand, and fully detailed.