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Detailed operating instructions for the rotary evaporator (condensed version)

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Detailed operating instructions for the rotary evaporator (condensed version)

Original Title: Detailed Operating Instructions for Rotary Evaporator (Simplified Version) Detailed operating instructions for the rotary evaporator (condensed version) Rotary evaporator is the equipment for purification and distillation test. Through constant temperature heating, the evaporation bottle rotates under negative pressure to make the material form a film evenly on its inner wall, evaporate efficiently, and then condense to recover the solvent, so as to achieve the effect of purification and separation. Is the chemical industry, institutions of higher learning and scientific research laboratories and other units for the manufacture and analysis of experiments on the concentration, drying, recovery and other more ideal essential basic instruments. At present, the production technology of laboratory equipment in our country is very mature, and more and more university laboratories have begun to use advanced equipment, especially the rotary evaporator (http://www.antaiyq.com/), which is mainly used for continuous distillation of large amounts of volatile solvents under reduced pressure. In particular, the reaction product can be separated and purified by concentrating the extract liquid and distilling the receiving liquid during chromatographic separation. The basic principle of rotary evaporator is vacuum distillation, that is, under vacuum, when the solvent is distilled, the distillation flask is continuously rotating. In recent years, it has been widely used in university laboratories. In addition to university laboratories, other industries have begun to use new distillers, such as chemical industry, machinery, food and other industries. The rotary evaporator is a comprehensive rotary evaporator for oil bath and water bath. The design of the whole machine is beautiful, reasonable and compact, the operation is simple and convenient, the temperature control is accurate, and the performance is reliable. The rotary evaporator can be used for both water bath and oil bath, and the temperature range is from room temperature to 180 deg C. The heat pipe automatically stops heat when that temperature is higher than the set temperature. The water bath pot has small volume and rapid temperature rise. The heating pot adopts Teflon compound pot, which is easy to clean. The steam conduit combines the advantages of foreign rotating seal systems. The specially designed steam conduit and vacuum sealing system are composed of PTFE composite materials, which have long service life and good sealing effect. After special process technology treatment, the sealing, corrosion resistance and wear resistance are enhanced. The integrated design of the steam seal pipe can prevent the occurrence of cross contamination, rotary vacuum evaporator ,thin film distillation, and the disassembly and cleaning are extremely convenient. Use procedure of rotary evaporator 1. Height adjustment: manual lifting, 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 connected with 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 to connect the vacuum pump. 3. Turn the speed control knob to the minimum to the left before starting the machine. Connect the power switch and the indicator light is on. 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. Flask is standard interface No.224, with 500ml and 1000ml flasks attached, and the amount of solution is generally not more than 505. Working principle of rotary evaporator The apparatus is electronically controlled so that the flask is rotated at a constant speed at the most suitable speed to increase the evaporation area. The evaporation flask was brought to a negative pressure state by a vacuum pump. And that evaporation flask is place in a water bath for constant temperature heat while rotating, and the solution in the flask is heated, 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. Use of rotary evaporator Rotary evaporator is mainly used for continuous distillation of large amounts of volatile solvents under reduced pressure. In particular, the reaction product can be separated and purified by concentrating the extract liquid and distilling the receiving liquid during chromatographic separation. The basic principle of rotary evaporator is vacuum distillation, that is, under vacuum, when the solvent is distilled, the distillation flask is continuously rotating. Structure: The distillation flask can be a pear-shaped or round-bottomed flask with a standard ground joint, which is connected to a pressure reduction pump through a highly refluxed serpentine condenser tube, and the other opening of the refluxed condenser tube is connected to 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,wiped film distillation, 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. Return to Sohu to see more Responsible Editor:. toptiontech.com

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