Rotary evaporator is mainly used for concentration, crystallization, drying, separation and coal recovery in the pharmaceutical, chemical and biopharmaceutical industries. The principle is as follows: the rotating bottle rotates at a constant speed under vacuum condition and heating condition at a constant temperature, and the material forms a large-area film on the bottle wall and evaporates efficiently. The dissolved coal vapor is cooled by a high-efficiency glass condenser and recovered in a collecting bottle,thereby greatly improving the evaporation efficiency, and is particularly selected for the concentration and purification of biological products which are easily decomposed and degenerated by high temperature.
Rotary evaporator has many advantages, however, there are still some disadvantages about rotary evaporator. They are as follows:
- Rotary evaporator can only process a single sample However, short path distillation can process several sample materials at the same time in one equipment, which makes up the rotary evaporator’s disadvantage.
- In the rotary evaporator equipment, the sealed equipment has a limited life, and needs to be replaced regularly. Therefore, it will take rotary evaporator users more time and money to replace the sealed equipment regularly.
- The sample materials may be exposed in the air, which will cause the contamination of the sample materials and extracted materials. The contamination of sample materials will cause the impurity of extracted materials, which decreases the quality of the experiments.
- In the rotary evaporator equipment, the glassware needs to be cleaned very often, because rotary evaporator needs a totally clean container to guarantee the purity of materials. If there is any impurity in the glassware, the extracted materials will be not pure.