Rotary evaporator, also called rotary evaporating machine, is a commonly used equipment in laboratories. It consists of a motor, distillation flask, heating pot, condenser, etc. It is mainly used for continuous distillation of volatile solvents under reduced pressure, and is Used in chemistry, chemical industry, bio-medicine and other fields.

Under negative pressure, the evaporating flask rotates in a constant temperature water bath, and the solution forms a thin film on the flask wall, increasing the evaporation area, to achieve efficient evaporation at low temperature, condensation recovery, concentration and separation of materials.

So, how to select a rotary evaporator? Before purchasing a rotary evaporator, ask yourself the following questions: What is the amount of distillation at one time? How many samples need to be distilled every day? What are the expected solvents for distillation? What is the approximate range of the boiling point of the solvent? Are these solvents flammable and explosive, or toxic and harmful? Once the experimental requirements and the type of solvent to be distilled are determined, we can start purchasing a rotary evaporator.

I. Determine the specifications of the rotary evaporator

The specifications of the rotary evaporator are usually distinguished by the volume of the evaporating flask.The size of the evaporating flask depends on the quantity of the material to be evaporated. Generally speaking, 2L, 3L, 5L rotary evaporators are suitable for small-scale laboratory tests, while 5L, 10L , 20L are suitable for pilot test, and 20L or 50L is suitable for pilot test and production. Of course, under special circumstances, we can also use the continuous feed tube to expand the volume of the evaporating flask, thereby expanding the continuous distillation volume to a certain extent.

II. Determine the distillation tasks that the rotary evaporator needs to complete

Distillation efficiency is critical. The distillation efficiency of a rotary evaporator determines the number of samples that can be distilled every day. In the case of the same solvent, the higher the distillation efficiency, the more samples are distilled. If the sample volume is large, more consideration is needed in the distillation efficiency.