Connectez-vous pour accéder plus rapidement aux meilleurs offres. Cliquez ici si vous n'avez pas encore un compte.

Precautions and Principle Analysis of Rotary Evaporator _ Flask Emploi Plein temps

1er mars 2023 à 4h58   Répétiteur   Saint-Louis   87 vues Référence: 460
Détails de l'annonce

Original title: Precautions and Principle Analysis of Rotary Evaporator Rotary evaporator Rotary evaporator, also known as rotary evaporator, is a common laboratory equipment, which is composed of motor, distillation flask, heating pot, condenser tube and other parts. It is mainly used for continuous distillation of volatile solvents under reduced pressure, and is used in chemistry, chemical industry, biomedicine and other fields. Structural principle of rotary evaporator: The distilling flask is a eggplant-shaped or round-bottomed flask with a standard ground joint, and is connected with a pressure reducing pump through a highly refluxing serpentine condensing tube, and the other opening of the refluxing condensing tube is connected with a receiving flask with a ground joint for receiving the evaporated organic solvent. A three-way piston is arranged between the condenser tube and the pressure reducing pump, when the system is communicated with the atmosphere, the distillation flask and the liquid receiving flask can be taken down to transfer the solvent, and when the system is communicated with the pressure reducing pump, the system should be in a pressure reducing state. When using, the pressure should be reduced first, and then the motor should be started to rotate the distillation flask. At the end, the machine should be stopped first, and then the atmosphere should be opened to prevent the distillation flask from falling off during rotation. As a heat source for distillation, it is often equipped with a corresponding thermostatic water tank. Working principle of rotary evaporator: By electronic control, the flask is rotated at a constant speed at a suitable speed to increase the evaporation area. The evaporation flask was brought to a negative pressure state by a vacuum pump. An evaporation flask is place in a water bath for constant temperature heat while rotating, and that solution in the flask is heated, rotary vacuum evaporator ,nutsche filter dryer, diffused and evaporate in the rotating flask under negative pressure. The rotary evaporator system can be sealed and decompressed to 400 to 600 mm Hg; the solvent in the distillation flask is heated by a heating bath, and the heating temperature can be close to the boiling point of the solvent; at the same time, the rotary evaporator system can rotate at a speed of 50 to 160 revolutions per minute, so that the solvent forms a film and the evaporation area is increased. In addition, under the action of the high-efficiency cooler, the hot steam can be quickly liquefied and the evaporation rate can be accelerated. Expand the full text Usage of rotary evaporator: 1. Turn on the low temperature coolant circulation pump Note that press the power button and then press the cooling button to start the cycle after the temperature is reduced to the required temperature. 2. Turn on the water pump to circulate water 3. Mount the distillation flask and secure with a clip Turn on the vacuum pump and start to rotate when there is a certain vacuum. 4. Adjust the height of distillation flask , spin speed, and set that appropriate bath temperature. 5. Stop rotating after steaming ? Open the atmosphere again, then stop the water pump, and finally remove the distillation flask. 6 Stop the low-temperature cooling liquid circulating pump, stop the water bath for heating, turn off the circulating water of the water pump, pour out the solvent in the receiving bottle, and clean the buffer ball and the receiving bottle. Precautions for use of rotary evaporator: 1. When in use, a small vacuum should be pumped first. (About 0.03 MPa), and then start the rotation to prevent the distillation flask from falling off; when stopping, stop the rotation first, hold the distillation flask by hand, open the atmosphere, and stop the vacuum pump when the vacuum degree drops to about 0.04 MPa to prevent the distillation flask from falling off and sucking back. 2. Each interface ? Sealing surface, sealing ring and joint shall be coated with a layer of vacuum grease before installation. 3. Water must be added before the heating tank is powered on. ? Dry firing without water is not allowed. 4. If the vacuum degree is too low, pay attention to check the joints. Air tightness of vacuum tube and glass bottle. 5. During rotary evaporation of air-sensitive substances Connect a nitrogen balloon to the exhaust port, introduce a burst of nitrogen to discharge the air in the rotary evaporator, and then connect the sample bottle for rotary evaporation. After steaming, release nitrogen to boost the pressure, then turn off the pump, and then take down the sample bottle and seal it. 6. If the sample is very viscous ? Slow down the rotation speed and rotate slowly by hand to form a new liquid level to facilitate the evaporation of solvent. (Photo: Pixabay) Last week's highlights How much do you know about cooling bath? Excellent! Good habits in the laboratory,jacketed glass reactor, you are the master of the experiment! Dry Goods | LC/MS Experience and Spectrum Analysis Determination and Extension of Validity Period of Common Reagents in Laboratory Unveiling the mystery of the moon is inseparable from the help of instruments and meters. Move your hands, you can give Xiaoyi a little star. Twinkle twinkle little star Share and like, don't you click one? Return to Sohu to see more Responsible Editor:.

Description de la société
Precautions and Principle Analysis of Rotary Evaporator _ Flask