Micro-negative pressure rotary evaporation all-in-one machine

Abstract

The invention relates to the technical field of chemistry and chemical engineering experimental equipment, in particular to a micro-negative pressure rotary evaporation all-in-one machine which comprises a distillation system, a heat exchange system and a controller which are mutually associated. The distillation system comprises an evaporation bottle, a two-way pipe, a locking mechanism, a driving motor, a vapor-liquid distributor, a condenser, a recovery bottle, an air pump and an air supply pipe which are connected in sequence, and is used for distilling, separating and purifying the volatile solvent; the heat exchange system comprises a compressor, a hot bathing pool, a cold bathing pool and a low-temperature pump and is used for heating an evaporation bottle of the evaporation system and refrigerating a condenser; the controller is used for controlling and adjusting the operation states of the distillation system and the heat exchange system, so that the volatile solvent is efficiently distilled and recycled in the closed micro-negative pressure distillation system. The micro-negative pressure rotary evaporation all-in-one machine has the beneficial effects that the bumping phenomenon of a common rotary evaporator can be completely eradicated, and the micro-negative pressure rotary evaporation all-in-one machine has the advantages of high distillation efficiency, environment friendliness and the like.

Description

Technical Field

[0001] The invention relates to the technical field of chemical experimental equipment, and in particular to a micro-negative pressure rotary evaporation integrated machine. Background Art

[0002] As a device that can quickly distill volatile reagents, the rotary evaporator is one of the most commonly used instruments in chemical laboratories, especially organic chemistry laboratories. The reasons why it can achieve efficient distillation of volatile reagents are mainly as follows: 1. The distillation flask is heated by a high-temperature water bath to increase the temperature of the solution to be evaporated; 2. The solution to be evaporated forms a layer of liquid film on the inner surface of the rotating reagent bottle, increasing the effective evaporation area of ​​the volatile reagent; 3. The vacuum pump is used to further reduce the vapor pressure in the distillation flask and increase the evaporation rate of the volatile solvent; 4. The vaporized reagent is liquefied in the low-temperature condenser and flows into the collection bottle, achieving rapid distillation of the volatile reagent at a lower temperature. Therefore, rotary evaporators generally have two disadvantages: 1. While providing vacuum conditions for the rotary evaporator, the vacuum pump will emit a certain amount of volatile solvents into the atmosphere. If not properly controlled, it will cause certain harm to the surrounding environment, especially the personal safety of the experimenters; 2. When the vacuum degree and / or the water bath temperature increases to a certain level, the solution in the distillation flask will splash and bubble, which will not only pollute the inner cavity of the rotary evaporator, but also reduce the product yield and the working efficiency of the equipment.

[0003] In order to reduce the pollution of the distillate solvent in the recovery bottle caused by solvent boiling, the Chinese Patent Office published a rotary evaporator (CN 109759161B), which can divide the recovery bottle into multiple areas by using intersecting partitions, and accurately guide the distillate into different recovery areas through a diversion device. This setting can not only effectively prevent the solvent in the diversion tube from flowing into two adjacent recovery areas during the reduced pressure distillation of the rotary evaporator, but also prevent the solvents in the recovery area from contaminating each other when the solvent boils. In addition, a rotary evaporator (CN 110215947B) published by the Chinese Patent Office prevents the solution in the rotary bottle from being sprayed into the receiving bottle due to boiling under reduced pressure by providing a three-way receiving pipe between the condensation system and the rotating device, and providing a funnel-shaped device and a second circular plate in the receiving pipe. Although the above work can reduce the adverse effects of the rotary evaporator boiling phenomenon on the experiment to a certain extent, it cannot fundamentally eliminate the rotary evaporator boiling phenomenon, and the vacuum system supporting the rotary evaporator also has the risk of solvent leakage. Summary of the invention

[0004] In view of the above-mentioned shortcomings of the prior art, the present invention provides a micro-negative pressure rotary evaporator integrated machine for solving the problems of the prior art. The provided micro-negative pressure rotary evaporator integrated machine comprises an interrelated distillation system, a heat exchange system and a controller, which can achieve efficient distillation and recovery of volatile solvents in a micro-negative pressure environment of a sealed distillation system. The effective benefit of the present invention is that the provided micro-negative pressure rotary evaporator integrated machine can not only completely eliminate the violent boiling phenomenon of the rotary evaporator, but also has the advantages of high working efficiency, environmental friendliness and high safety.

[0005] To achieve the above object, the technical solution adopted by the present invention is:

[0006] Provided is a micro-negative pressure rotary evaporator, comprising a distillation system, a heat exchange system and a controller which are interrelated and integrated in design.

[0007] Furthermore, the distillation system of the present invention comprises an evaporating flask, a two-way pipe, a locking mechanism, a driving motor, a vapor-liquid distributor, a condenser, a recovery bottle, an air pump and an air supply pipe connected in sequence, and is used for evaporation, liquefaction and recovery of volatile solvents.

[0008] Furthermore, the heat exchange system of the present invention comprises a compressor, a cold bath, a hot bath and a cryogenic pump, which are used to heat the evaporating flask and cool the condenser of the distillation system.

[0009] Furthermore, the evaporating flask of the distillation system of the present invention has a flask mouth connected to a vapor-liquid distributor via two-way pipes and is used for containing the solution to be evaporated.

[0010] Furthermore, the two-way pipe of the distillation system of the present invention is fixed inside the locking mechanism and can be rotated around the axis at an adjustable speed under the drive of the driving motor.

[0011] Furthermore, the vapor-liquid distributor of the distillation system of the present invention is simultaneously connected to the air inlet of the condenser, the liquid inlet of the recovery bottle, the air supply pipe and the two-way pipe, so that the gas and liquid entering the vapor-liquid distributor can flow in different directions under the dual effects of gravity and the air pump.

[0012] Furthermore, the distillation system condenser of the present invention comprises an air inlet, an air outlet, a liquid inlet, a serpentine coil and a liquid outlet. Under the action of the coolant of the heat exchange system, the volatile solvent is liquefied and flows into the collecting bottle through the solid-liquid separator, and the non-condensable gas is discharged from the condenser through the air outlet.

[0013] Furthermore, the air delivery pipe of the present invention comprises an upper port, an expansion pipe and a lower port, the outer wall of the expansion pipe is sealed and connected to the upper left side of the vapor-liquid distributor, the upper port is connected to the condenser outlet through an air pump, and the lower port extends into the interior of the evaporating flask through the vapor-liquid distributor and the two-way pipe.

[0014] Furthermore, the air pump of the distillation system of the present invention is used to send the non-condensable gas discharged from the gas outlet of the condenser back to the evaporation flask through the air supply pipe.

[0015] Furthermore, the heat exchange system compressor of the present invention comprises a cooling end and a heat dissipation end; the cooling end is connected to the cold bath refrigerator to provide a cold source for the cold bath; the heat dissipation end is connected to the hot bath radiator to provide a heat source for the hot bath.

[0016] Furthermore, the heat exchange system heat bath of the present invention comprises a radiator for containing a heat bath medium and heating the evaporating flask.

[0017] Furthermore, the cold bath pool of the heat exchange system of the present invention comprises a refrigerator, a liquid outlet and a liquid return port; the liquid outlet of the cold bath pool is connected to the liquid inlet of the evaporation system condenser serpentine tube through a low-temperature pump, and the liquid return port of the cold bath pool is connected to the liquid outlet of the evaporation system condenser serpentine tube, and is used to hold the cooling medium and circulate the cooling medium into the evaporation system condenser serpentine tube under the push of the low-temperature pump.

[0018] Furthermore, the controller of the present invention is used to control the switch and working status of the distillation system and the heat exchange system. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In order to more clearly illustrate the technical solution of the present invention, the drawings required for use in the embodiments and application examples will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For relevant technical personnel, other drawings can be derived based on the present invention without paying creative work.

[0020] Figure 1 It is a schematic diagram of the overall structure of a micro-negative pressure rotary evaporation integrated machine provided by the present invention;

[0021] Figure 2 It is a structural schematic diagram of an evaporation system of a micro-negative pressure rotary evaporator provided by the present invention;

[0022] Figure 3 It is a structural schematic diagram of a heat exchange system of a micro-negative pressure rotary evaporator provided by the present invention;

[0023] Figure 1 to Figure 3Explanation of reference numerals: 100: distillation system; 110: evaporation flask; 120: two-way pipe; 130: locking mechanism; 140: driving motor; 150: vapor-liquid distributor; 160: condenser; 161: air inlet; 162: serpentine coil; 163: air outlet; 164: liquid inlet; 165: liquid outlet; 170: recovery bottle; 171: liquid collecting port; 180: air pump; 190: air supply pipe; 191: upper port; 192: expansion pipe; 193: lower port; 200: heat exchange system; 210: compressor; 211: heating end; 212: cooling end; 220: hot bath; 221 radiator; 230: cold bath; 231: refrigerator; 232: liquid outlet; 233: liquid return port; 240: cryogenic pump; 300: controller. DETAILED DESCRIPTION

[0024] In order to make the purpose, technical solution and advantages of the present invention clearer, the technical solution of the present invention will be clearly and completely described below in conjunction with the accompanying drawings. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by relevant technicians without creative work are within the scope of protection of the present invention.

[0025] In the description of the present invention, it should be noted that the terms such as "connected", "connected" and "connected" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integrated connection; it can be directly connected, indirectly connected through an intermediate medium, or connected internally between two components; directional words such as "upper", "lower", "left", "right", "top", "bottom" and "end" are based on the drawings in the specification, and relevant technical personnel can understand the actual meaning of the above terms in the present invention according to the specific circumstances. Example 1

[0026] like Figure 1 to Figure 3 The micro-negative pressure rotary evaporator shown in the figure comprises an integrated and interrelated distillation system 100, a heat exchange system 200 and a controller 300.

[0027] The distillation system 100 includes an evaporating flask 110, a two-way pipe 120, a locking mechanism 130, a driving motor 140, a vapor-liquid distributor 150, a condenser 160, a recovery bottle 170, an air pump 180 and an air supply pipe 190; the heat exchange system 200 includes a compressor 210, a hot bath 220, a cold bath 230 and a cryogenic pump 240.

[0028] The condenser 160 includes an air inlet 161 , a serpentine coil 162 , an air outlet 163 , a liquid inlet 164 and a liquid outlet 165 .

[0029] The air supply pipe 190 includes an upper port 191 , an expansion pipe 192 and a lower port 193 .

[0030] The hot bath 220 has a built-in radiator 221 .

[0031] The cold bath 230 includes a refrigerator 231 , a liquid outlet 232 and a liquid return port 233 .

[0032] The evaporating flask 110 has a flask mouth 111 which is connected to the lower end of the two-way pipe 120 .

[0033] The upper end of the two-way pipe 120 is connected to the lower right side of the vapor-liquid distributor 150 , and is fixed inside the locking mechanism 130 , and can rotate around the axis at an adjustable speed under the action of the driving motor 140 .

[0034] The vapor-liquid distributor 150 is connected to the air inlet 161 of the condenser 160 at the top and to the liquid collecting port 171 of the recovery bottle 170 at the bottom. The upper left side is sealed to the outer wall of the expansion tube 192 of the air supply pipe 190, and the lower right side is connected to the upper end of the two-way pipe 120.

[0035] The condenser 160 includes an air inlet 161, a serpentine coil 162, an air outlet 163, a liquid inlet 164 and a liquid outlet 165; the air inlet 161 is connected to the upper end of the vapor-liquid distributor 150; the air outlet 163 is connected to the upper end 191 of the air supply pipe 190 through the air pump 180.

[0036] The lower port 193 of the air supply pipe 190 is inserted into the evaporation flask 100 through the vapor-liquid distributor 150 and the two-way pipe 120 .

[0037] The compressor 210 has a heating end 211 connected to a radiator 221 , and a cooling end 212 connected to a refrigerator 231 .

[0038] The liquid outlet 232 of the cold bath 230 is connected to the liquid inlet 164 of the serpentine tube 162 through the cryogenic pump 240 , and the liquid return port 233 is connected to the liquid outlet 165 of the serpentine tube 162 .

[0039] The controller 300 controls the switch and working status of the driving motor 140 and the air pump 180 of the distillation system 100 and the compressor 210 and the cryogenic pump 240 of the heat exchange system 200 through control lines.

[0040] The general operation method of the micro-negative pressure rotary evaporator is as follows: The first step is to clean and dry all components of the micro-negative pressure rotary evaporator distillation system, and press Figure 1The related components are assembled together according to the connection relationship shown; the second step is to use a silicone tube to connect the liquid outlet 232 and the liquid return port 233 of the cold bath 230 to the liquid inlet 164 and the liquid outlet 165 of the condenser 160 respectively; the third step is to add an appropriate amount of distilled water and coolant to the hot bath 220 and the cooling pool 230 respectively; the fourth step is to add an appropriate amount of solvent to be evaporated into the evaporation bottle 100; the fifth step is to turn on the power supply to power on the air pump 180, the compressor 210, the cryopump 240 and the controller 300; the sixth step is to use the controller 3 00 sets the speed of the driving motor 140 and the operating temperatures of the hot bath 220 and the cold bath 230, and starts the driving motor 140 and the compressor 210 to work; the seventh step, when the temperatures of the hot bath 220 and the cold bath 230 reach the set temperatures, turns on the cryogenic pump 240 to allow the cooling medium to circulate between the cold bath 230 and the condenser 160; the eighth step, turns on the air pump 180, driving the solvent vapor and the non-condensable gas in the evaporating bottle 110 to enter the condenser 160 through the two-way pipe 120 and the vapor-liquid separator 150 in turn.

[0041] The working principle of the micro-negative pressure rotary evaporation integrated machine is as follows: After the solvent vapor to be evaporated and the non-condensable gas enter the condenser 160, the solvent vapor to be evaporated condenses and gathers on the surface of the serpentine tube 162 due to its low boiling point, and enters the recovery bottle 170 through the vapor-liquid distributor 150 under the action of gravity; at the same time, the non-condensable gas re-enters the evaporation bottle 110 through the air outlet 163 of the condenser 160, the air pump 180, and the air supply pipe 190 under the action of the air pump 180 to participate in the micro-negative pressure distillation. Since the liquefaction of the solvent vapor makes the closed distillation system a micro-negative pressure system, the micro-negative pressure rotary evaporator provided by this patent can not only realize the efficient distillation of the solvent, but also eliminate the boiling phenomenon that often occurs in the rotary evaporator. In addition, the closed distillation system gives the micro-negative pressure rotary evaporator many advantages, including environmental friendliness and high safety. Application Example 1

[0042] The micro-negative pressure rotary evaporator involved in Example 1 is used as a rotary distillation device to perform micro-negative pressure distillation on deionized water. The volume of the evaporating flask 100 is 500 ml, the mass of the deionized water in the evaporating flask 100 is 200 g, the temperature of the hot bath 220 is set to 60 degrees Celsius, and the temperature of the cold bath 230 is set to 5 degrees Celsius. When each system of the micro-negative pressure rotary evaporator meets the working requirements, the air pump 180 and the cold pump 240 are turned on to perform micro-negative pressure distillation on the deionized water. The experiment was repeated three times, and the average distillation rate was approximately 100 grams per hour, and the average recovery rate was approximately 95%. Application Example 2

[0043] The micro-negative pressure rotary evaporator involved in Example 1 is used as a rotary distillation device to perform micro-negative pressure distillation on anhydrous ethanol. The volume of the evaporating flask 100 is 500 ml, the mass of the anhydrous ethanol in the evaporating flask 100 is 200 g, the temperature of the hot bath 220 is set to 40 degrees Celsius, and the temperature of the cold bath 230 is set to minus 5 degrees Celsius. When each system of the micro-negative pressure rotary evaporator meets the working requirements, the air pump 180 and the cold pump 240 are turned on to perform micro-negative pressure distillation on anhydrous ethanol. The experiment was repeated three times, and the average distillation rate was about 150 grams per hour, and the average recovery rate was about 97%. Application Example 3

[0044] The micro-negative pressure rotary evaporator involved in Example 1 is used as a rotary distillation device to perform micro-negative pressure distillation on dichloromethane. The volume of the evaporating flask 100 is 500 ml, the mass of dichloromethane in the evaporating flask 100 is 200 grams, the temperature of the hot bath 220 is set to 25 degrees Celsius, and the temperature of the cold bath 230 is set to minus 20 degrees Celsius. When each system of the micro-negative pressure rotary evaporator meets the working requirements, the air pump 180 and the cold pump 240 are turned on to perform micro-negative pressure distillation on dichloromethane. The experiment was repeated three times, and the average distillation rate was about 400 grams per hour, and the average recovery rate was about 99%. Application Example 4

[0045] The micro-negative pressure rotary evaporator involved in Example 1 is used as a rotary distillation device to perform micro-negative pressure distillation on ethyl acetate. The volume of the evaporating flask 100 is 500 ml, the mass of ethyl acetate in the evaporating flask 100 is 200 g, the temperature of the hot bath 220 is set to 30 degrees Celsius, and the temperature of the cold bath 230 is set to minus 15 degrees Celsius. When each system of the micro-negative pressure rotary evaporator meets the working requirements, the air pump 180 and the cold pump 240 are turned on to perform micro-negative pressure distillation on ethyl acetate. The experiment was repeated three times, and the average distillation rate was about 450 grams per hour, and the average recovery rate was about 98%. Application Example 5

[0046] The micro-negative pressure rotary evaporator involved in Example 1 is used as a rotary distillation device to perform micro-negative pressure distillation on petroleum ether (boiling range: 60-90 degrees Celsius). The volume of the evaporating flask 100 is 500 ml, the mass of the petroleum ether in the evaporating flask 100 is 200 grams, the temperature of the hot bath 220 is set to 30 degrees Celsius, and the temperature of the cold bath 230 is set to minus 20 degrees Celsius. When each system of the micro-negative pressure rotary evaporator meets the working requirements, the air pump 180 and the cold pump 240 are turned on to perform micro-negative pressure distillation on the petroleum ether. The experiment was repeated three times, and the average distillation rate was about 390 grams per hour, and the average recovery rate was about 98%.

[0047] Finally, it is to be noted that the description of the composition of the micro-negative pressure rotary evaporator integrated machine in the present invention and the above-mentioned application examples have fully demonstrated that the micro-negative pressure rotary evaporator integrated machine provided by the present invention can be widely used for micro-negative pressure distillation of various reagents. Due to space limitations, it is impossible to list the appearance dimensions, connection methods and applicable micro-negative pressure experiments of the micro-negative pressure rotary evaporator integrated machine provided by the present invention one by one, so the above-mentioned embodiments and application examples are only used to illustrate the technical solution of the present invention, rather than to limit it; although the present invention has been described in detail with reference to the above-mentioned embodiments and application examples, relevant technical personnel should understand that it is still possible to modify the technical solutions recorded in the above-mentioned embodiments, or to replace some of the technical features therein by equivalents; and these modifications or equivalent replacements do not make the essence of the corresponding technical solutions deviate from the spirit and protection scope of the present invention.

Claims

1. A micro-negative pressure rotary evaporator, characterized in that: It includes the interconnected distillation system, heat exchange system and controller in an integrated design.

2. According to claim 1, a micro-negative pressure rotary evaporator is characterized in that: The distillation system is equipped with some or all accessories including an evaporating flask, a two-way pipe, a locking mechanism, a driving motor, a vapor-liquid distributor, a condenser, a recovery bottle, an air pump and an air delivery pipe; preferably, all accessories are equipped.

3. The micro-negative pressure rotary evaporator according to claim 1, characterized in that: The heat exchange system is equipped with some or all accessories including a compressor, a hot bath, a cold bath and a cryogenic pump; preferably, all accessories are equipped.

4. The micro-negative pressure rotary evaporator according to claim 1, characterized in that: The distillation system, heat exchange system and controller are designed in an integrated manner.

5. The micro-negative pressure rotary evaporator according to claim 2, characterized in that: The lower end of the air delivery pipe of the distillation system is inserted into the evaporation flask through a vapor-liquid distributor and a two-way pipe.

6. The micro-negative pressure rotary evaporator according to claim 2, characterized in that: The distillation system is a closed cycle distillation system that does not emit solvent vapor to the surrounding environment during operation.

7. The micro-negative pressure rotary evaporator according to claim 5, characterized in that: The solvent vapor and the circulating non-condensable gas in the closed distillation system enter the condenser together under the push of the air pump and are liquefied inside the condenser; the liquefied solvent flows into the recovery bottle through the vapor-liquid distributor; the non-condensable gas, under the push of the air pump, returns to the evaporation bottle through the air delivery pipe to participate in the micro-negative pressure distillation again.

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