Generally, the component liquids of interest in applications of rotary evaporation are research solvents that one desires to remove from a sample after an extraction, such as following a natural product isolation or a step in an organic synthesis. Vacuum evaporators as a class function because lowering the pressure above a bulk liquid lowers the boiling points of the component liquids in it.
Modern equipment often adds features such as digital control of vacuum, digital display of temperature and rotational speed, and vapor temperature sensing.
Commercial instruments are available that include the basic features, and various traps are manufactured to insert between the evaporation flask and the vapor duct. Glassware used in the vapor stream and condenser can be simple or complex, depending upon the goals of the evaporation, and any propensities the dissolved compounds might give to the mixture (e.g., to foam or "bump"). The vacuum system used with rotary evaporators can be as simple as a water aspirator with a trap immersed in a cold bath (for non-toxic solvents), or as complex as a regulated mechanical vacuum pump with refrigerated trap.
A mechanical or motorized mechanism to quickly lift the evaporation flask from the heating bath. A condensate-collecting flask at the bottom of the condenser, to catch the distilling solvent after it re-condenses. A condenser with either a coil passing coolant, or a " cold finger" into which coolant mixtures such as dry ice and acetone are placed. A heated fluid bath (generally water) to heat the sample. 
A vacuum system, to substantially reduce the pressure within the evaporator system. A vapor duct that is the axis for sample rotation, and is a vacuum-tight conduit for the vapor being drawn off the sample. A motor unit that rotates the evaporation flask or vial containing the user's sample. The main components of a rotary evaporator are: In research the most common form is the 1L bench-top unit, whereas large scale (e.g., 20L-50L) versions are used in pilot plants in commercial chemical operations. Walter Büchi developed a world first commercial rotary evaporator, which separates substances with different boiling points, and greatly simplifies work in research laboratories. It was first commercialized by the Swiss company in 1957. Rotary evaporators are also used in molecular cooking for the preparation of distillates and extracts.Ī simple rotary evaporator system was invented by Lyman C. When referenced in the chemistry research literature, description of the use of this technique and equipment may include the phrase "rotary evaporator", though use is often rather signaled by other language (e.g., "the sample was evaporated under reduced pressure"). A rotary evaporator ( rotovap) is a device used in chemical laboratories for the efficient and gentle removal of solvents from samples by evaporation.
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