The rotary evaporator is an indispensable instrument for evaporating, distilling, separating chemicals, using rotating flasks to dry powder and crystallization in the scientific research and production process of medicine, chemical, biological products, and other industries.
1.Working principle Lab 20l/50l rotary evaporator working principle is to use the water (oil) bath unit heating to control the temperature of the rotating bottle, and the rotating mechanism to drive the rotating bottle to run at a preset speed to make the solvent in the bottle form a thin film, increase the evaporation area, and then form a condenser and a vacuum acquisition device. The vacuum cooling unit is a system device that efficiently separates or distills materials.
2. Main components and their functions a. Motor Classified by function, the motors of the lab 20l/50l rotary evaporator are divided into rotating motors and lifting motors. The rotating electric machine is the main component of the rotating mechanism, and it can be an AC motor or a DC motor. The user can control the steady-state speed of the rotating bottle by setting the rotating speed through the “speed regulator” and “SET” keys set on the operation panel; the lifting motor is the driving part of the rotating bottle lifting mechanism, generally a DC 24V motor.
b.Rotating bottle The rotating bottle is the core component for holding materials and performing rotary evaporation. Generally speaking, the volume is divided into 1L, 2L, 5L, 10L, 20L, 50L. 1L and 2L rotating bottles are used for small-scale experiments in the laboratory; 5L and above rotating bottles are used for pilot trials or production.
c. Vacuum system Lab rotary evaporator is composed of glass components such as a rotating bottle, glass rotating shaft, three-way bottle, condenser, recovery bottle of the rotary evaporator, and external vacuum acquisition and control device. Used to reduce the air pressure in the evaporation system and improve the evaporation efficiency.
d. Water (oil) bath The water (oil) bath is the heating source of the rotating bottle. The user can adjust the temperature of the bath through the control system to change the evaporation rate of the material.
e. Condenser Generally, a double serpentine condenser tube is used. This structure can increase the heat exchange area and improve condensation efficiency. The condenser is equipped with an external low-temperature circulating liquid pipeline interface and a pressure reducing device interface, which can be connected to a “low-temperature source and temperature control device” or a “vacuum acquisition and control device” as needed to further improve the condensation efficiency.
f. Recycle bottles The recovery bottle is connected to the lower part of the condenser, and the condensed solvent is collected and temporarily stored in the bottle.
3. Factors that affect the evaporation rate of the rotary evaporator Bath temperature, rotating speed of rotating bottle, system negative pressure state, condenser temperature control, and condenser structure.
4.Selection Before purchasing a lab rotary evaporator, you should first clarify the classification of the use environment. If the operating environment is an explosion-hazardous place, you should choose an instrument with the corresponding explosion-proof level.
If the place of use is a corrosive environment, the corrosion resistance requirements should be emphasized when purchasing the instrument. Otherwise, the operating rate and the expected service life of the instrument will be difficult to guarantee.
Most common lab rotary evaporators produced by manufacturers have a dustproof and waterproof rating of IP20 and are not suitable for use in strong magnetic fields, corrosive environments, and explosive hazardous locations
The volume of the rotating bottle is another key indicator of purchasing a rotary evaporator. The user can determine the volume of the rotating bottle according to the number of experimental materials and then determine the instrument selection.