1、 Preparation before operation
1. Check the integrity of the equipment: Confirm that the evaporator bottle, condenser tube, collection bottle, sealing ring and other components are not damaged or aged, and the oil level of the vacuum pump should be within the normal range.
2. Assembly equipment: Fix the evaporator bottle on the rotating shaft, ensure a tight connection with the condenser tube, and turn on the cooling water circulation system.
3. Sample preparation: Pour the concentrated solution into an evaporation bottle, with the liquid level not exceeding 2/3 of the bottle capacity (organic solvent not exceeding 1/3).
2、 Operation process
1. Vacuum pumping: Slowly start the vacuum pump and adjust the vacuum degree to 0.08-0.09 MPa (depending on the boiling point of the solvent).
2. Heating and Rotation:
Set the water bath temperature (such as controlling ethanol evaporation at around 80 ℃).
Start the rotating motor, reduce the initial speed, and gradually accelerate after the solution forms a uniform thin film.
3. Monitoring process: Observe the evaporation status to prevent boiling (zeolite can be added or heating can be paused).
3、 End operation
1. Release vacuum: First turn off the heating and slowly open the vent valve after the evaporation bottle cools down.
2. Disassembly and cleaning: Stop rotating, remove the evaporator bottle and collection bottle, turn off the power and cooling water.
4、 Precautions
1. Safety protection: Wear goggles and lab coats to avoid solvent splashing.
2. Temperature control: Thermally sensitive samples require low-temperature operation to prevent component decomposition.
3. Maintenance: Regularly check the sealing ring and vacuum pump to avoid dry boiling of the water bath pot.