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What are Rotary Evaporators and How Do They Work?

A lab evaporator is a standard piece of chemistry equipment for removing solvents from samples or creating a concentrated form. How do rotary evaporators – also called rotating evaporators or rotovaps – work? Let’s take a look.

What is Rotary Evaporation?

RE200-Pro flask

Evaporation is a gentle, efficient way to remove solvents and the process of rotary evaporation is a reduced-pressure distillation.

It involves placing a sample within a round-bottomed flask, which is then placed in the rotovap’s heated water bath and rotated. A vacuum pump reduces the pressure above the solvent. This draws the solvent away from the sample (distributed as a thin film across the flask's interior, while the compound remains. A glass condenser cools the solvent, which is then recovered in a collection bottle.

What are the Advantages of Using Rotary Evaporators?

One of the main advantages of a rotary evaporator is its speed. Since the flask doesn’t have to be heated to the solvent’s boiling point, the process is faster, more gentle and less likely to damage the sample by causing thermal decomposition.

The lower temperature of the water bath also causes less wear and tear on the rotovap, extending the life of the apparatus.

What is a Rotovap used for?

The extraction of solid drugs is one of the primary uses of a rotary evaporator. Removing water from liquids and trace components also produces a concentrate, which is often useful for a variety of applications besides medicine.

Rotary evaporator distillation can be used in cannabis- and solvent-based extractions, as well as molecular gastronomy (a food science that examines the physical and chemical transformations that occur during cooking) for the preparation of distillates and extracts.

Selecting a Rotary Evaporator


RE100-Pro Rotary Evaporator

Sonic Supply offers a selection of high-quality DLAB rotary evaporators, including the RE100-Pro Rotary Evaporator with Glassware Condenser Set and the RE200-Pro 20 Liter Digital Rotary Evaporator.

The RE100-Pro Rotary Evaporator comes with a glassware condenser set. The temperature of its large 5L water/oil heating bath ranges from ambient to 180°C. It holds several patents, including a unique condenser with a 1,500cm cooling surface.

DLAB’s RE200-Pro 20 Liter Digital Rotary Evaporator includes a double-layer, high-efficiency condenser for efficient sample recovery. A switching valve allows for continuous collection without compromising the system vacuum and solvent distillation. The unit’s heating bath features an insulated structural design that allows a far lower surface temperature than the bath.

RE200-Pro Rotary Evaporator

If you have any questions about rotary evaporators, call or email us. We’re here to help!


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