The rotary evaporators are essential laboratory equipment for concentration, crystallization, drying, separation and solvent recovery in pharmaceutical,chemical and bio-pharmaceutical fields and other fields. The basic working process can be described below. The rotating flask is heated thermostatically and can rotate at a constant speed. Then the material forms a large area of thin film on the inner surface of the flask. The solvent vapor is recycled in the collecting bottle after being cooled by high-efficiency glass condenser, which greatly improves the evaporation efficiency. A rotary evaporator is especially suitable for the concentration and purification of biological products which are easy to decompose and denature at high temperature.
The rotary evaporator has become more and more popular since it was invented due to it does possess much more advantages than other distillation equipment, as follows:
1. The rotary evaporator has a faster evaporation rate.
The rotating flask is a specially designed part of the rotary evaporator, which can rotate at a constant speed so that materials can form a widespread film evenly on the inner surface of the flask, which greatly improves the evaporation efficiency. As well, continuous feeding and high vacuum degree contributes to the faster evaporation rate.
2. The rotary evaporator has a better security.
The stainless steel and aluminum alloy are widely used in the mechanical structure, and all glass parts are made of heat-resistant high borosilicate glass, which ensure a better security. Besides, the water/oil bath can be equipped with transparent covers to prevent splashing, and anti-explosion frequency changer and dynamo are available as well. All of these designs contribute to better security.
3. The rotary evaporator has a more convenient operation.
It’s much more convenient to use a rotary evaporator, because of the electrodeless speed regulation, digital display K Type Sensor and intelligent temperature control and other designs adopted by it.
In conslusion, the rotary evaporator is more widely used than other distillation equipment. It is generally used for the extraction and concentration of solid drugs, which can prevent the spray of chemicals. What’s more, people also use a rotary evaporator to concentrate liquid through removing water from it. Yet the reduced pressure evaporator and traditional evaporator can only be used for drying of easily decomposable liquid medicines compared to the rotary evaporator.