Rotary evaporators are distillation units that incorporate an efficient condenser with a rotary flask system. As the flask containing the solvent is rotated it continually transfers a thin layer of liquid over the entire inner surface. This gives a very large surface area for evaporation that is effected by heating from the accessory water or oil bath. The solvent steam is cooled by a high-efficiency glass condenser and recovered in the collection bottle, which greatly improves the evaporation efficiency, especially for the concentration and purification of the biologic which is easily decomposed at high temperature.
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