Rotary evaporator is mainly composed of: motor, distillation flask, heating pot, condenser tube and other parts commonly used in laboratory equipment. Commonly used configurations are shown in the figure below:
1. Common configuration of rotary evaporator and precautions for use
1) Heating water bath: the general heating medium is clean water. If there is a special need for temperature, it can be replaced with silicone oil or high-temperature silicone oil! Although the manufacturer will provide a cover on the water bath, the frequency of use is not high during use; the static time can prevent dust from entering the water bath or oil bath, and keep the water bath or oil. Bath clean.
2) Condenser: The general cooling medium is water. If the ambient temperature is high and the condensation effect is not good, it can be replaced with an ethanol bath, and the device is equipped with a circulating refrigerator. The ethanol after cooling is pressed into the condenser for cooling treatment. In extremely cold weather, when the condenser is still not in use, the water in the condenser should be drained overnight to prevent the water from solidifying and expanding and rupturing the condenser.
3) Decompression equipment: often configured as a water pump. For some solvents with high boiling points, the water pump can be replaced with an oil pump. Pay attention to the requirements of the equipment when replacing it.
2. Tips for using rotary evaporator
Experience in the use of the rotary evaporator. During the use of the rotary evaporator, the water in the water bath, the water in the pump and the entire device must be kept clean and clean.
1). In the use of rotary evaporation, high temperature silicone grease is used between the rotary bottle and the rotary evaporator. The ground bottle and the main body are connected together, and a plastic standard mouth clip is provided. The connection is not very strong, and the rotary steaming bottle is often dropped into the water bath during use.
2) During the use of rotary evaporator, if there is a power failure, the water in the water pump will be poured back into the rotary evaporator system.
3) In the rotary evaporation, if the boiling point of the solvent is low, it is easy to occur during the rotary evaporation process. The rotary evaporation liquid in the rotary evaporation bottle will flush into the condenser tube, and then into the wetted bottle. The above situation is always inevitable. If the rotary steaming is kept clean, then the formed oil-water mixture, or liquid-solid mixture, can be filtered, concentrated and refined, and column separation is used to obtain the target product. If it is not clean, just wait to cry!
3. Pilot Rotary Evaporator
In the market, the rotary evaporator is used as a pilot plant, and the volume is generally 50L. The operation used is not much different from the laboratory rotary evaporator.
1. The rotary steaming bottle is basically fixed, and the height of the oil bath is raised and lowered by the iron frame to adjust the contact between the oil bath and the rotary steaming bottle;
2. When feeding, it is different from directly pouring the material into the rotary steaming bottle in the laboratory. The reaction liquid to be rotated is sucked in through the feeding valve.
4. Precautions for the use of rotary evaporator
Precautions for use:
1. Add distilled water to the water bath to avoid scale formation in the pot;
2. There is no water in the water bath and cannot be energized;
3. Avoid organic solvents on the surface of the instrument;
4. When the vacuum degree does not reach 0.08Mpa, the sealing ring should be replaced in time to avoid damage to the machine;
5. It is necessary to use a straightened rotating bottle, otherwise it will damage the glass straight pipe.