Rotary evaporator is a device based on the principle of vacuum distillation, widely used in fields such as chemistry, chemical engineering, biomedicine, etc. Its core working principle is to improve evaporation efficiency and achieve liquid separation and purification through pressure reduction and rotation.

The working principle of a rotary evaporator mainly includes the following aspects:

• Vacuum distillation: The rotary evaporator reduces the internal pressure through a vacuum system, lowering the boiling point of the liquid and allowing distillation to occur at lower temperatures.

Rotating flask: The flask containing the liquid mixture to be separated rotates under the drive of the motor, and the liquid forms a thin film on the inner wall of the flask, increasing the evaporation area.

Heating: The flask is usually heated by a water bath or oil bath to vaporize the volatile components in the liquid mixture.

• Condensation: The vaporized steam enters the condenser and is cooled by a cooling medium before re condensing into a liquid, which is collected in a receiving bottle.

The main components of a rotary evaporator include:

Rotating flask: usually a pear shaped or circular glass container with various capacity sizes, connected to a motor through a sealed rotating joint.

• Condenser: Generally a double-layer sleeve structure, the cooling medium circulates in the interlayer, and the cooling efficiency depends on the temperature and flow rate of the cooling medium.

Vacuum system: including vacuum pump and vacuum controller, used to reduce the air pressure inside the system.

Heating device: usually a water bath or oil bath, with a temperature controller to accurately set the heating temperature.

The rotary evaporator has a wide range of applications in multiple fields:

Chemistry and chemical engineering: used for dehydration, deacidification, concentration, purification, separation, etc., suitable for the separation of plant extracts, concentration of biochemical drugs, etc.

• Biopharmaceuticals: Used for the preparation of natural plant extracts, traditional Chinese medicine, catalysts, anticancer drugs, etc.

Food industry: used for the purification and concentration of food additives.