A 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 flask rotates at a constant speed and temperature under vacuum and heating condition, and the material forms a large-area film on the inner wall of the flask, evaporating efficiently. The dissolved coal vapor is cooled by a high-efficiency glass condenser and recovered in a receiving flask, thereby greatly improving a evaporation efficiency. And the rotary evaporator is particularly selected for the concentration and purification of biological products which are easily decomposed and degenerated by high temperature.
A rotary evaporator has many advantages, however, there are still some disadvantages as well. They are as follows:
- A rotary evaporator can only process a single sample. However, short path distillation can process several sample materials at the same time in one equipment.
- In the rotary evaporator equipment, the sealed equipment has a limited life, and needs to be replaced regularly. Therefore, it will take 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 a 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.
What is the Function of a Rotary Evaporator?
A rotary evaporator is an essential separation equipment, which can remove a valtile solvent from a liquid mixture through evaporation and condensation. For example, a rotary evaporator can be used to remove ethanol from the mixture of ethanol and cbd oil in order to improve the purity of cbd oil. Also, it can be used to remove water within fruit juice, in order to make the fruit juice have a higher concentration. It can be seen that a rotary evaporator has a great number of functions.
What is the Primary Advantage of a Rotary Evaporator over Traditional Distillation?
Higher efficiency, together with better accuracy, is the primary advantage of using a rotary evaporator over distillation.
A rotary evaporator is electronically controlled so that the rotation of the flask can be kept at a constant speed, and the mixture can form a film on the inner surface of the flask, creating a larger surface for heating. All of these factors contribute to the faster evaporation speed of solvent, which means higher efficiency and better accuracy.
But the distillation is less efficient and accurate than a rotary evaporator. When adopting the distillation, a mixture is heated to the temperature at which one component will boil. Then the vapor from the hot mixture is collected and recondensed into liquid, which is fast. But actually many kinds of mixtures cannot be separated this way.
Therefore, comparing to the distillation, a rotary evaporator is more widely used in the chemical laboratories, industrial, bio-pharmaceutical and food-making fields.