Before purchasing a rotary evaporator, it is necessary to clarify some questions, such as the amount of one-time distillation, the approximate number of samples that need to be distilled every day, what solvents are expected to be distilled, what is the approximate range of the boiling points of the solvents, and whether these solvents are Flammable, explosive or toxic and harmful solvents. Once you have determined your experimental requirements and the type of solvent to be distilled, you can start shopping for a rotary evaporator.

First, clarify the specifications of the rotary evaporator

The specifications of the rotary evaporator are usually distinguished by the volume of the evaporating bottle. The size of the evaporating bottle required depends on the quantity of the material to be evaporated. Generally speaking, 2L, 3L, and 5L rotary evaporators are suitable for small laboratory experiments; 5L, 10L and 20L are suitable for pilot test; 20L and 50L are suitable for pilot test and production. Of course, under special circumstances, the volume of the evaporating flask can also be expanded by means of the continuous feeding pipe, thereby expanding the volume of one continuous distillation to a certain extent. There are also water baths and oil baths.

2. Clarify the distillation tasks that the rotary evaporator needs to complete

1. Distillation efficiency

The distillation efficiency of the rotary evaporator determines the number of samples that can be distilled per day. In the case of the same solvent, the higher the distillation efficiency, the greater the number of samples to be distilled. If the sample volume is large, it is necessary to pay more attention to the distillation efficiency when purchasing a rotary evaporator www.yuxiang17.com.

2. Security risk assessment

The safety risk of distillation mainly comes from the solvent and heating medium of distillation.

1) If the heating medium is silicone oil, the ignition point should be at least 25°C higher than the maximum temperature of the heating pot.

2) If the distillation solvent is flammable and explosive, explosion-proof glass components can be used as the first choice. After distillation, it is best if the instrument can automatically deflate, so as to avoid manual deflation too fast and cause explosion.

3) To optimize the laboratory environment, a secondary condensation device can be selected to maximize the recovery of the distillation solvent.

3. The most important thing about the rotary evaporator is that the sealing is better:

Tightness is the first reference for rotary evaporators. This is related to the normal use and service life of the instrument. The sealing service life has a great relationship with the design level, manufacturing level, and selection of materials of different manufacturers. "Actual vacuum degree" and "vacuum holding time" are specific measurement standards.

4. The grinding mouth of the rotary bottle is generally 24 and 29 mouths:

Ports 24 and 29 are standard ports commonly used in laboratories. The 29 ports have high strength and are easy to clean. They are more suitable for matching with imported rotary evaporators, and are also conducive to optional bottle withdrawal devices. The vacuum pump is an essential product for the rotary evaporator, and the circulating water vacuum pump is mostly used.

5. Condensation effect

The temperature of tap water varies greatly with the seasons, and the temperature in summer is relatively high, the solvent recovery rate is low, and the tap water is easy to cause discoloration and scaling of the condenser.

The plan is to select a suitable low-temperature coolant circulating pump. The selection is to pay attention to the appropriate combination of "refrigeration capacity" and "low temperature", as well as "circulation interface" and "circulation volume and circulation pressure". The company provides supporting low-temperature equipment.

6. Improve the service life of the rotary evaporator

Do not use it according to the instruction manual.

When the reaction is completed, the rotary evaporator should be cleaned in time.

The outer wall of the rotary evaporator should be kept clean.

The rotary evaporator is controlled by imported high-grade inverter, and the stepless speed regulation makes the glass rotary bottle rotate at a constant speed, and the material forms a large-area uniform film on the bottle wall, and then the rotary bottle is heated evenly by a controllable constant temperature water bath. Under the high-speed evaporation, the solvent vapor is cooled by the high-efficiency glass double condenser and recovered in the collection bottle.

The rotary evaporator is a device that uses an evaporating flask (flask) to increase the evaporation area and place it in a water bath under reduced pressure while rotating and heating, so that the solution in the flask is diffused and evaporated. It is an ideal essential basic instrument for concentration, drying and recycling in chemical industry, pharmaceutical industry, colleges and universities and scientific research laboratories for manufacturing and analysis experiments.