Rotary evaporator composition, working principle, use steps _ solvent _ condensation _ boiling point

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Originally published as can you really use a tape measure? ☞ This is article 8321 posted by Metalworking

Original title: Composition, working principle and use steps of rotary evaporator Working principle of rotary evaporator The distillation flask rotates at a constant speed at the most appropriate speed through motor control to increase the evaporation area, and the evaporation flask is in a negative pressure state through vacuum pumping to reduce the boiling point of the solution and accelerate the evaporation speed. Vacuum evaporators are used as a means of evaporation, because lowering the pressure above the liquid will lower the boiling point of the component liquid, thus speeding up the evaporation rate to a certain extent. The evaporation bottle is arranged in the water bath kettle to be heated at constant temperature while rotating, and the solution in the bottle is heated, diffused and evaporated under the condition of negative pressure in the rotating bottle. The evaporation system can be sealed and decompressed to 400 to 600 millimeters of mercury,wiped film distillation, the solvent in the distillation flask is heated by a heating bath, the heating temperature can be close to the boiling point of the solvent, meanwhile,cbd crystallization equipment, the solvent can be rotated at a speed of 50 to 160 revolutions per minute to form a film to increase the evaporation area, and in addition, the hot vapor can be quickly liquefied under the action of a high-efficiency condenser tube to accelerate the distillation rate. Main components of rotary evaporator 1. Rotate the motor ? Drive the evaporation bottle by rotation. 2. Evaporation piping ? The support shaft for the evaporation bottle to rotate and vacuum seal the pipe to extract the steam from the material. 3. Vacuum system ? Reduce the pressure in the evaporator system and lower the boiling point of the material. 4. Heat the bath pan Water or oil is often used to heat the material. 5. Condenser In order to speed up the condensation efficiency, it is usually made into a double snake ring type, and then add a condensing agent such as dry ice and acetone to condense the sample. 6. Condensate collection bottle at bottom of condenser ? Used to capture the distillation solvent after recondensation and collect the sample. 7. Lifting device , a mechanical or motorized mechanism that quickly lifts an evaporation flask from a heated bath. Operation steps of rotary evaporator 1. Height adjustment: manual lifting, rotary vacuum evaporator ,thin film distillation, rotate the hand wheel on the column, clockwise to rise, reverse to fall. Electric lifting, hand touch up key to lift the host, hand touch down key to lower the host. 2. There are two external joints on the condenser, which are used to connect the cooling water. One end is connected to the inlet water, and the other end is connected to the outlet water. Generally, it is used to connect the tap water. The lower the temperature of the condensed water, the better the effect. The upper end is equipped with a vacuum pump, which is used for vacuum pumping. 3. Before starting the machine, turn the speed control knob to the left, connect the power switch indicator light, and then slowly turn it to the right to the required speed. Use medium and low speed for half of the large evaporation bottle, and use lower speed for the solution with high viscosity. The flask is standard interface No.224, with 500ml and 1000ml flasks attached, and the amount of solution is generally not more than 505. Typically in rotary evaporation applications, the constituent liquid of interest is the study solvent that one wishes to remove from the sample after extraction, for example after a step in natural product isolation or organic synthesis, where the liquid solvent can be removed without undue heating of the often complex and sensitive solvent mixture. Rotary evaporation is commonly and conveniently used to separate "low-boiling" solvents such as n-hexane or ethyl acetate from compounds that are solid at room temperature and pressure. However,jacketed glass reactor, if there is minimal co-evaporation (azeotropic behavior), and sufficient difference in boiling points at the selected temperature and reduced pressure, careful application also allows the solvent to be removed from the sample containing the liquid compound. Return to Sohu to see more Responsible Editor:.

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