The water bath rotary evaporator drives the evaporation bottle to rotate at a constant speed through an electronic control system. This design enables the liquid sample to form a uniform thin film on the inner wall of the bottle, increasing the contact area between the solution and the heat source, laying the foundation for efficient evaporation. The supporting vacuum pump is responsible for reducing the internal pressure of the system. According to physical principles, the boiling point of the solvent will significantly decrease in low-pressure environments. This negative pressure state not only allows distillation to be carried out at lower temperatures, but also accelerates the process of molecular escape, making it particularly suitable for handling high boiling point or thermosensitive substances.

The evaporator bottle is placed in an accurately controlled water bath, providing gentle and uniform heat energy through stable hot water circulation. Compared to direct flame heating, the water bath method can avoid local overheating that may cause sample decomposition, while ensuring a more uniform distribution of heat. Under the combined action of centrifugal force generated by rotation, reduced pressure environment, and continuous heating, the solvent rapidly vaporizes and is re condensed and recovered through a condensing device. This process fully achieves effective separation of solute and solvent, and maintains a low working temperature throughout the entire process.

Precautions for using a water bath rotary evaporator:

1. Water bath related: Distilled water should be added to the water bath to prevent scaling inside the pot; And electricity cannot be supplied when there is no water. Due to the high water temperature in the water bath, the water evaporates continuously. It is necessary to check the water level every half an hour, and when it is low, water must be added to prevent the water from evaporating completely.

2. Instrument maintenance and safety: The surface of the instrument should avoid contamination with organic solvents. When the vacuum degree does not reach 0.08Mpa, the sealing ring should be replaced in a timely manner to avoid damaging the machine. A straightened rotating bottle must be used, otherwise it will damage the glass straight tube.

3. Standard operating sequence: When using, first draw a small vacuum (about 0.03MPa), then turn on the rotation to prevent the distillation flask from slipping off; When stopping, first stop the rotation, hold the distillation flask with your hand, let it breathe, and wait for the vacuum degree to drop to around 0.04MPa before stopping the vacuum pump to prevent the distillation flask from falling off and being sucked back.

4. Other precautions: When the work is completed or suspended, the vacuum should be released to prevent the backflow of sewage in the vacuum pump. During the cleaning process, be careful and handle all glassware with care to prevent breakage.