Distillation purification device for the preparation of diethyl malonate

Abstract

A distillation and purification device for preparing diethyl malonate relates to the technical field of distillation equipment, comprising a support base, a heating tank is vertically fixed on the top of the support base, a heating assembly is provided on the inner bottom of the heating tank, a pressure reducing assembly is provided at a position above the heating assembly in the heating tank, a boosting assembly and a plurality of condensing assemblies are also provided on the top of the support base, the plurality of condensing assemblies are evenly distributed around the boosting assembly along the circumference, the plurality of condensing assemblies are connected to the inner cavity of the heating tank through the boosting assembly, a feed valve connected to the inner cavity of the heating tank is fixedly provided at a position between the heating assembly and the pressure reducing assembly on the outer wall of the heating tank, and a discharge valve connected to the inner cavity of the heating tank is fixedly provided at the bottom of the heating tank. The present invention solves the problems of uneven heating of the filtrate by the existing distillation device for preparing diethyl malonate; the problem of long time required for complete condensation of the vaporized diethyl malonate; and the problem of slow evaporation rate of liquid diethyl malonate in the filtrate when the filtrate is heated.

Description

Technical Field

[0001] The invention relates to the technical field of distillation equipment, in particular to a distillation purification device for preparing diethyl malonate. Background Art

[0002] Diethyl malonate is an important fine chemical raw material. Since the methylene hydrogen in its molecule can be easily replaced by various groups, it can generate a variety of important derivatives and is widely used in various chemical production fields, including food, medicine, pesticides, industrial dyes, liquid crystal materials and other industries. In recent years, with the further development and application of downstream products of diethyl malonate at home and abroad, the demand for diethyl malonate has increased sharply, and the domestic demand for diethyl malonate is relatively large.

[0003] The preparation process of diethyl malonate is as follows: ethyl chloroacetate, magnetic silica gel-immobilized cobalt metal complex acetate, ammonia water, and ethanol are added to a stainless steel autoclave, mixed evenly, the air in the autoclave is replaced with carbon monoxide, and then carbon monoxide is filled in and maintained at a certain pressure, heated and stirred for reaction to obtain a reaction solution, the reaction solution is cooled, filtered and separated to obtain a filtrate, and the filtrate is distilled to obtain the product diethyl malonate, so a distillation device is required in the preparation process of diethyl malonate.

[0004] The existing distillation device for preparing diethyl malonate gradually exposed its shortcomings during use, which are mainly manifested in the following aspects:

[0005] First, the filtrate is heated unevenly, resulting in a long time for the filtrate to reach the target temperature. Specifically, the distillation tank in the existing distillation device is usually heated by a heating jacket installed on its outer wall. During the process of heating the distillation tank body by the heating jacket, the temperature of the middle area inside the distillation tank is much lower than the temperature of the surrounding areas. Therefore, the filtrate in the tank is heated unevenly, resulting in a long time for the filtrate to reach the target temperature.

[0006] Second, it takes a long time to completely condense the vaporized diethyl malonate, resulting in low distillation efficiency. Specifically, in order to ensure that the vaporized diethyl malonate can be completely condensed, the flow rate of the vaporized diethyl malonate is usually reduced to make it flow slowly, thereby increasing the contact time between the diethyl malonate and the condensation component, so that the diethyl malonate is fully in contact with the condensation component for condensation. Therefore, it takes a long time to completely condense the vaporized diethyl malonate, resulting in low distillation efficiency.

[0007] Third, the evaporation rate of liquid diethyl malonate in the filtrate is slow. Specifically, the evaporation rate of liquid diethyl malonate in the distillation tank is affected by factors such as the liquid temperature and the air pressure in the tank. At a certain temperature, the lower the air pressure in the tank, the faster the evaporation rate of liquid diethyl malonate. As mentioned in the second question, in order to ensure that the vaporized diethyl malonate can be completely condensed, the flow rate of the vaporized diethyl malonate is usually reduced to prolong its contact time with the condensation component. Reducing the flow rate of the vaporized diethyl malonate will inevitably cause it to accumulate in the distillation tank. Therefore, the air pressure in the distillation tank is relatively high, which in turn slows the evaporation rate of the liquid diethyl malonate.

[0008] In summary, the prior art obviously has inconveniences and defects in practical use, so it is necessary to improve it. Summary of the invention

[0009] In view of the defects in the prior art, the technical problem to be solved by the present invention is to provide a distillation purification device for the preparation of diethyl malonate, which can not only heat the filtrate evenly, but also heat the filtrate quickly, thus shortening the time required for the filtrate to reach the target temperature and greatly improving the heating efficiency of the filtrate;

[0010] The device can also perform pressurization treatment on the diethyl malonate to be condensed, and make the pressurized diethyl malonate reciprocate through the condensation assembly for condensation. The boiling point of the diethyl malonate can be increased by pressurization, thereby reducing the difference between the actual temperature and the boiling point of the vaporized diethyl malonate, thereby accelerating the condensation speed of the diethyl malonate and improving the distillation efficiency.

[0011] The device can also reciprocately provide a low-pressure environment in the tank during the process of heating and vaporizing the liquid diethyl malonate in the tank, thereby accelerating the evaporation rate of the liquid diethyl malonate.

[0012] To solve the above problems, the present invention provides the following technical solutions:

[0013] A distillation and purification device for preparing diethyl malonate, comprising a support base, a heating tank is vertically fixed on the top of the support base, a heating assembly is provided on the inner bottom of the heating tank, a pressure reducing assembly is provided at a position above the heating assembly in the heating tank, a pressurizing assembly and a plurality of condensing assemblies are also provided on the top of the support base, a plurality of the condensing assemblies are uniformly distributed around the pressurizing assembly along the circumferential direction, a plurality of the condensing assemblies are connected to the inner cavity of the heating tank through the pressurizing assembly, a feed valve connected to the inner cavity of the heating tank is fixedly provided at a position of the outer wall of the heating tank between the heating assembly and the pressure reducing assembly, and a discharge valve connected to the inner cavity of the heating tank is fixedly provided at the bottom of the heating tank;

[0014] The heating component includes an outer fixed cylinder vertically penetrating the bottom of the heating tank, an inner fixed cylinder with an opening at the bottom coaxially arranged inside the outer fixed cylinder, the bottom of the inner fixed cylinder is fixedly connected to the inner bottom of the outer fixed cylinder, the top of the inner fixed cylinder passes through the outer fixed cylinder upward and extends into the heating tank, a liquid pumping cylinder with openings at both ends is coaxially arranged inside the inner fixed cylinder, the top and bottom of the liquid pumping cylinder are fixedly connected to the inner top of the inner fixed cylinder and the inner bottom of the outer fixed cylinder respectively, a partition is coaxially fixedly connected to the position of the inner wall of the liquid pumping cylinder located in the heating tank, a liquid pumping piston is coaxially provided at a position above the partition inside the liquid pumping cylinder and is slidably and sealingly connected to the inner wall thereof, a driving rod is fixedly connected to the top of the liquid pumping piston, the top of the driving rod passes through the inner fixed cylinder upward and is connected to the decompression assembly, and the driving rod is slidably connected to the inner fixed cylinder.

[0015] The inner bottom of the heating tank is evenly distributed with a plurality of vertically fixed heating cylinders along the circumferential direction, the upper outer wall and the lower outer wall of the heating cylinder are respectively fixedly connected with an upper connecting pipe and a lower connecting pipe connected with the inner cavity thereof, one of the ports of the upper connecting pipe is connected with the inner cavity of the inner fixed cylinder, and one of the ports of the lower connecting pipe is connected with the inner cavity of the outer fixed cylinder, the outer wall of the heating cylinder is fixedly sleeved with a plurality of heat-conducting fins evenly distributed along its axial direction at a position between the upper connecting pipe and the lower connecting pipe, the inner bottom of the heating cylinder is coaxially fixedly connected with a drain pipe, the upper port of the drain pipe extends upward through the heating cylinder to the outside, and the partition A liquid inlet main pipe is coaxially fixedly connected to the bottom of the partition, and a liquid inlet check valve is provided on the liquid inlet main pipe. A plurality of liquid inlet branch pipes connected to the lower port thereof are evenly distributed along the circumferential direction below the liquid inlet main pipe. One of the ports of the liquid inlet branch pipe passes through the liquid extraction cylinder, the inner fixed cylinder and the outer fixed cylinder in sequence and extends to the inner bottom of the heating tank. A plurality of liquid outlet pipes are evenly distributed along the circumferential direction at the bottom of the partition, and a liquid outlet check valve is provided on the liquid outlet pipe. One of the ports of the plurality of liquid outlet pipes passes through the liquid extraction cylinder and the inner fixed cylinder in sequence, and respectively coaxially passes through the plurality of lower connecting pipes and is connected to the plurality of liquid discharge pipes accordingly.

[0016] A hot water inlet pipe and a hot water outlet pipe connected to the hot water unit are provided below the heating tank. One of the ports of the hot water inlet pipe is connected to the inner cavity of the outer fixed cylinder. One of the ports of the hot water outlet pipe passes through the outer fixed cylinder and is connected to the inner cavity of the inner fixed cylinder.

[0017] The inner bottom of the heating tank is evenly distributed along the circumference with a plurality of drive shafts that are arranged to rotate along a plumb line. The plurality of drive shafts and a plurality of heating cylinders are alternately arranged along the circumference. The outer wall of the drive shaft is evenly distributed along the circumference with a plurality of stirring blades.

[0018] As an optimized solution, the decompression assembly includes a decompression circular plate vertically slidingly sealed to the inner wall of the heating tank, the top of the driving rod is fixedly connected to the bottom of the decompression circular plate, the top of the decompression circular plate is evenly distributed with a plurality of slide grooves along the circumferential direction, the bottom of the slide groove is provided with a sliding plate along the radial sliding seal of the decompression circular plate, the bottom of the slide groove is penetrated with an exhaust hole, the top of the decompression circular plate is coaxially fixed with a support cylinder, the support cylinder is coaxially provided with a slidably arranged driving circular plate, the outer wall of the support cylinder is evenly distributed with a plurality of avoidance grooves penetratingly arranged along the circumferential direction, the side wall of the driving circular plate is evenly distributed with a plurality of swinging plates hinged thereto along the circumferential direction, one end of a plurality of the swinging plates respectively passes through a plurality of avoidance grooves to extend to the outside, and are correspondingly hinged to a plurality of the sliding plates.

[0019] As an optimized solution, the condensation assembly includes a support plate vertically fixedly arranged on the top of the support base, the end of the support plate is vertically reciprocatingly slidably provided with a vertically arranged condensation tank, a fixedly arranged condensation cylinder is coaxially arranged in the condensation tank, the outer wall of the condensation cylinder is slidably and sealedly connected to the inner wall of the condensation tank, an external fixed tube is coaxially fixedly connected to the inner top of the condensation cylinder, an internal fixed tube is coaxially arranged inside the external fixed tube, the top of the internal fixed tube is fixedly connected to the inner top of the condensation cylinder, the bottoms of the external fixed tube and the internal fixed tube both pass downward through the condensation cylinder and the condensation tank in turn, and are fixedly connected to the top of the support base, the external fixed tube is slidably and sealedly connected to the condensation tank, and the outer wall of the external fixed tube is located at a position below the inner part of the condensation cylinder and is circumferentially distributed with a plurality of holes that are connected to the inner cavity The outer wall of the inner fixed tube is located at the upper part of the condensing cylinder and is evenly distributed along the circumferential direction with a plurality of upper liquid tubes connected to its inner cavity. One of the ports of the upper liquid tube passes through the outer fixed tube and extends into the condensing cylinder. The condensing cylinder is evenly distributed along the circumferential direction with a plurality of vertically arranged condensing tubes. The top and bottom of the condensing tube extend upward and downward to the outside of the condensing cylinder respectively. The outer wall of the condensing tube is located at the position fixed in the condensing cylinder and is equipped with a plurality of heat exchange fins evenly distributed along its axial direction. A cold water inlet pipe and a cold water outlet pipe connected to the chiller are provided below the condensing tank. One of the ports of the cold water inlet pipe is connected to the inner cavity of the outer fixed tube, and one of the ports of the cold water outlet pipe passes through the outer fixed tube and is connected to the inner cavity of the inner fixed tube.

[0020] A lifting circular plate is coaxially provided at a position above the condensing cylinder in the condensing tank and is connected to the condensing cylinder in a sliding and sealing manner. Two limiting cylinders are vertically fixed on the inner top of the condensing tank. Two vertically arranged lifting rods are fixedly connected to the top of the lifting circular plate. The tops of the two lifting rods extend into the two limiting cylinders respectively and are correspondingly connected to the two limiting cylinders in a sliding manner. Compression springs are provided in the limiting cylinders. The two ends of the compression springs are correspondingly pressed against the lifting rods and the inner tops of the limiting cylinders. A through hole is provided through the top of the condensing tank.

[0021] A drain valve connected to the inner cavity of the condensation tank is fixedly provided at the bottom of the condensation tank.

[0022] As an optimized solution, the boosting assembly includes a vertically fixed boosting tank, a boosting piston with a sliding seal is coaxially arranged in the boosting tank, a follower rod with a vertical reciprocating sliding arrangement is fixedly connected to the bottom of the boosting piston, the bottom end of the follower rod extends downward through the boosting tank to the outside, and is slidably connected to the boosting tank, an intake pipe connected to the inner cavity of the boosting tank is coaxially fixed to the top of the boosting tank, an intake check valve is provided on the intake pipe, one of the ports of the intake pipe is connected to the inner cavity of the heating tank, a plurality of exhaust pipes connected to the inner cavity of the boosting tank are evenly distributed along the circumferential direction on the top of the boosting tank, an exhaust valve and an exhaust check valve are provided on the exhaust pipes, and one end of a plurality of the exhaust pipes is correspondingly connected to the inner cavities of a plurality of condensing tanks.

[0023] As an optimized solution, the bottom of the booster tank is fixedly connected to two vertically arranged support vertical plates, the bottom of the support vertical plates is fixedly connected to the top of the support base, a support cross plate is horizontally arranged between the two support vertical plates, the opposite side walls of the support cross plate are fixedly connected to the two support vertical plates respectively, and a control reciprocating telescopic cylinder is fixedly arranged on the top of the support cross plate, and the telescopic end of the control reciprocating telescopic cylinder is fixedly connected to the driven rod.

[0024] As an optimized solution, a plurality of drive motors are fixedly provided at the bottom of the heating tank, and the output ends of the plurality of drive motors all pass through the heating tank and are fixedly connected to a plurality of drive shafts accordingly.

[0025] As an optimized solution, a rotatably arranged single-thread screw is coaxially provided on the inner top of the support tube, the bottom end of the single-thread screw passes through the driving circular plate and is rotatably connected to the inner bottom of the support tube, and the single-thread screw is threadedly connected to the driving circular plate.

[0026] As an optimized solution, a servo motor is fixedly provided on the top of the support tube, and the output end of the servo motor passes through the support tube and is fixedly connected to the single-thread screw.

[0027] As an optimized solution, two built-in telescopic cylinders are fixedly provided on the inner top of the heating tank, and the telescopic ends of the two built-in telescopic cylinders are fixedly connected to the pressure reducing circular plate.

[0028] As an optimized solution, the condensation tank is slidably connected to the support plate through a fixed plate, and two driving reciprocating telescopic cylinders are fixedly provided at the top of the support base below the condensation tank, and the telescopic ends of the driving reciprocating telescopic cylinders are fixedly connected to the condensation tank.

[0029] Compared with the prior art, the present invention has the following beneficial effects:

[0030] 1. When heating the filtrate in the heating tank, the hot water of the hot water unit enters the outer fixed cylinder through the hot water inlet pipe, and enters into several heating cylinders through several lower connecting pipes respectively. The hot water in the heating cylinder enters the inner fixed cylinder through the upper connecting pipe, and is discharged to the hot water unit through the hot water outlet pipe for reheating. During the circulation of hot water, the driving motor drives the driving shaft and the stirring blades to rotate, thereby stirring the filtrate in the heating tank. At the same time, the built-in telescopic cylinder drives the pressure reducing circular plate to rise and fall, thereby driving the driving rod and the liquid pumping piston to slide vertically. When the liquid pumping piston slides upward, the filtrate at the bottom of the heating tank enters into the liquid pumping cylinder in one direction through several liquid inlet branches, the liquid inlet main pipe and the liquid inlet one-way valve, and the liquid pumping piston slides downward. When the stirring blade is moved, the filtrate in the liquid extraction cylinder enters into the plurality of liquid discharge pipes in one direction through the plurality of liquid discharge pipes and the liquid discharge one-way valves, and the filtrate in the liquid discharge pipe flows upward and is discharged through the upper port thereof, thereby making the filtrate in the heating tank flow vertically, and under the stirring of the stirring blades, the filtrate at all positions in the heating tank can contact with the heating cylinder and the heat-conducting fins and perform heat exchange, thereby being able to evenly heat the filtrate in the heating tank, and the hot water in the heating cylinder can also heat the filtrate when the filtrate passes through the liquid discharge pipe, further accelerating the heating speed of the filtrate, realizing the function of evenly heating the filtrate, and the heating speed of the filtrate is fast, shortening the time required for the filtrate to reach the target temperature, and greatly improving the heating efficiency of the filtrate;

[0031] 2. The built-in telescopic cylinder drives the pressure reducing circular plate to slide vertically. When the pressure reducing circular plate slides downward from the highest position, the servo motor drives the single-thread screw to rotate, thereby controlling the driving circular plate to slide upward. With the cooperation of the swing plate, the sliding plate slides inward and opens the exhaust hole. When the pressure reducing circular plate slides downward to be close to the liquid surface of the filtrate, the vaporized diethyl malonate in the heating tank enters above the pressure reducing circular plate through the exhaust hole. When the pressure reducing circular plate slides upward from the lowest position, the servo motor drives the single-thread screw to rotate, thereby controlling the driving circular plate to slide downward. With the cooperation of the swing plate, the sliding plate slides outward and closes the exhaust hole. When the pressure reducing circular plate slides upward to the highest position, the air pressure in the area of ​​the heating tank below the pressure reducing circular plate is reduced. During the process of the pressure reducing circular plate rising and falling, it can provide a low-pressure environment for the heating tank back and forth, thereby accelerating the evaporation rate of liquid diethyl malonate;

[0032] 3. When one of the exhaust valves is opened, the boost tank is connected to one of the condensing tanks, and the reciprocating telescopic cylinder is controlled to drive the driven rod and the boost piston to slide back and forth vertically. When the boost piston slides downward, the vaporized diethyl malonate in the area above the pressure reducing circular plate in the heating tank enters the boost tank in one direction through the intake pipe and the intake check valve. When the boost piston slides upward, the diethyl malonate in the boost tank enters the condensing tank in one direction through the exhaust pipe and the exhaust check valve. As the content of diethyl malonate in the condensing tank increases, the internal air pressure of the condensing tank increases, the lifting circular plate slides upward, and the compression spring is compressed. When the content of diethyl malonate in the condensing tank reaches a certain value, the vaporized diethyl malonate can be transported to the remaining condensing tanks by controlling the opening and closing of other exhaust valves. The cold water of the chiller passes through the cold water inlet pipe. Enters into the outer fixed tube, and enters into the condenser through several lower liquid pipes. The cold water in the condenser enters into the inner fixed tube through several upper liquid pipes, and is discharged to the chiller through the cold water outlet pipe for re-cooling. In the process of circulating, the cold water can continuously cool down the condenser tube with the cooperation of the heat exchange fins, driving the reciprocating telescopic cylinder to drive the condenser tank to which diethyl malonate is added to slide vertically reciprocatingly. The diethyl malonate in the condenser tank is cooled by reciprocating through the condenser tube. The condensed diethyl malonate is collected at the bottom of the condenser tank. The boiling point of diethyl malonate can be increased by pressurization, thereby reducing the difference between the actual temperature and the boiling point of the vaporized diethyl malonate. At the same time, with the cooperation of several condenser tanks, the condensation speed of diethyl malonate is greatly accelerated, thereby improving the distillation efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] In order to more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the following is a brief introduction to the drawings required for the specific embodiments or the description of the prior art. In all the drawings, similar elements or parts are generally identified by similar reference numerals. In the drawings, the elements or parts are not necessarily drawn according to the actual scale.

[0034] Figure 1 It is a structural schematic diagram of the present invention;

[0035] Figure 2 It is a structural schematic diagram of the heating component of the present invention;

[0036] Figure 3 It is a schematic diagram of the structure inside the outer fixing tube and the inner fixing tube of the present invention;

[0037] Figure 4 It is a structural schematic diagram of the decompression assembly of the present invention;

[0038] Figure 5 It is a structural schematic diagram of the condensation component of the present invention;

[0039] Figure 6It is a schematic diagram of the structure inside the condensing cylinder of the present invention;

[0040] Figure 7 It is a structural schematic diagram of the booster assembly of the present invention;

[0041] Figure 8 It is a schematic diagram of the overall structure of the present invention.

[0042] In the figure: 1-support base; 2-heating component; 3-feeding valve; 4-heating tank; 5-pressure reducing component; 6-built-in telescopic cylinder; 7-condensing component; 8-boosting component; 9-driving reciprocating telescopic cylinder; 10-driving motor; 11-external fixed cylinder; 12-internal fixed cylinder; 13-liquid inlet branch pipe; 14-partition; 15-liquid pumping piston; 16-liquid pumping cylinder; 17-stirring blade; 18-driving shaft; 19-supporting horizontal plate; 20-upper connecting pipe; 21-liquid discharge pipe; 22-heating cylinder; 23-driving rod; 24-heat conducting fin; 25-liquid inlet main pipe; 26-liquid inlet check valve; 27-liquid outlet pipe; 28-liquid outlet check valve; 29-lower connecting pipe; 30-hot water inlet pipe; 31-discharge valve; 32-hot water outlet pipe; 33-pressure reducing circular plate; 34-single threaded rod; 35-support Cylinder; 36-servo motor; 37-avoidance groove; 38-driving circular plate; 39-slide groove; 40-exhaust hole; 41-swing plate; 42-sliding plate; 43-inner fixed tube; 44-outer fixed tube; 45-heat exchange fin; 46-condenser tube; 47-upper liquid pipe; 48-condenser tube; 49-lower liquid pipe; 50-drain valve; 51-support plate; 52-fixed plate; 53-lifting circular plate; 54-lifting rod; 55-limiting cylinder; 56-compression spring; 57-through hole; 58-condenser tank; 59-cold water inlet pipe; 60-cold water outlet pipe; 61-control reciprocating telescopic cylinder; 62-boosting tank; 63-boosting piston; 64-exhaust check valve; 65-exhaust valve; 66-exhaust pipe; 67-intake pipe; 68-intake check valve; 69-driven rod; 70-support vertical plate. DETAILED DESCRIPTION

[0043] The following embodiments of the technical solution of the present invention are described in detail in conjunction with the accompanying drawings. The following embodiments are only used to more clearly illustrate the technical solution of the present invention, and are therefore only used as examples, and cannot be used to limit the protection scope of the present invention.

[0044] like Figures 1 to 8As shown, a rectification and purification device for preparing diethyl malonate comprises a supporting base 1, a heating tank 4 is vertically fixedly arranged on the top of the supporting base 1, a heating assembly 2 is arranged on the inner bottom of the heating tank 4, a pressure reducing assembly 5 is arranged at a position above the heating assembly 2 in the heating tank 4, a boosting assembly 8 and a plurality of condensing assemblies 7 are also arranged on the top of the supporting base 1, the plurality of condensing assemblies 7 are uniformly distributed around the boosting assembly 8 along the circumferential direction, the plurality of condensing assemblies 7 are connected to the inner cavity of the heating tank 4 through the boosting assembly 8, a feed valve 3 connected to the inner cavity of the heating tank 4 is fixedly arranged on the outer wall of the heating tank 4 between the heating assembly 2 and the pressure reducing assembly 5, and a discharge valve 31 connected to the inner cavity of the heating tank 4 is fixedly arranged at the bottom of the heating tank 4;

[0045] The heating assembly 2 includes an outer fixed cylinder 11 vertically penetrating the bottom of the heating tank 4, an inner fixed cylinder 12 with an opening at the bottom is coaxially arranged in the outer fixed cylinder 11, the bottom of the inner fixed cylinder 12 is fixedly connected to the inner bottom of the outer fixed cylinder 11, the top of the inner fixed cylinder 12 extends upward through the outer fixed cylinder 11 into the heating tank 4, a liquid extraction cylinder 16 with openings at both ends is coaxially arranged in the inner fixed cylinder 12, the top and bottom of the liquid extraction cylinder 16 are fixedly connected to the inner top of the inner fixed cylinder 12 and the inner bottom of the outer fixed cylinder 11 correspondingly, a partition 14 is coaxially fixedly connected to the position of the inner wall of the liquid extraction cylinder 16 located in the heating tank 4, a liquid extraction piston 15 is coaxially provided in the position above the partition 14 and is slidably and sealedly connected to the inner wall of the liquid extraction cylinder 16, a driving rod 23 is fixedly connected to the top of the liquid extraction piston 15, the top of the driving rod 23 passes through the inner fixed cylinder 12 upward and is connected to the decompression assembly 5, and the driving rod 23 is slidably connected to the inner fixed cylinder 12,

[0046] The inner bottom of the heating tank 4 is evenly distributed with a plurality of vertically fixed heating tubes 22 along the circumferential direction. The upper outer wall and the lower outer wall of the heating tube 22 are respectively fixedly connected with an upper connecting pipe 20 and a lower connecting pipe 29 connected with the inner cavity thereof. One of the ports of the upper connecting pipe 20 is connected with the inner cavity of the inner fixed tube 12, and one of the ports of the lower connecting pipe 29 is connected with the inner cavity of the outer fixed tube 11. The outer wall of the heating tube 22 is fixedly sleeved with a plurality of heat-conducting fins 24 evenly distributed along the axial direction thereof at a position between the upper connecting pipe 20 and the lower connecting pipe 29. The inner bottom of the heating tube 22 is coaxially fixedly connected with a drain pipe 21. The upper port of the drain pipe 21 extends upward through the heating tube 22 to the outside. The bottom of the partition 14 is fixedly provided with a plurality of heat-conducting fins 24 evenly distributed along the axial direction thereof. A liquid inlet main pipe 25 is coaxially fixedly connected to the bottom of the partition 14, and a liquid inlet check valve 26 is provided on the liquid inlet main pipe 25. A plurality of liquid inlet branch pipes 13 connected to the lower port thereof are uniformly distributed along the circumferential direction below the liquid inlet main pipe 25. One of the ports of the liquid inlet branch pipe 13 passes through the liquid extraction cylinder 16, the inner fixed cylinder 12 and the outer fixed cylinder 11 in sequence and extends to the inner bottom of the heating tank 4. A plurality of liquid outlet pipes 27 are uniformly distributed along the circumferential direction at the bottom of the partition 14, and a liquid outlet check valve 28 is provided on the liquid outlet pipe 27. One of the ports of the plurality of liquid outlet pipes 27 passes through the liquid extraction cylinder 16 and the inner fixed cylinder 12 in sequence, and coaxially passes through a plurality of lower connecting pipes 29 respectively, and then is connected to a plurality of liquid discharge pipes 21 accordingly.

[0047] A hot water inlet pipe 30 and a hot water outlet pipe 32 connected to the hot water unit are provided below the heating tank 4. One of the ports of the hot water inlet pipe 30 is connected to the inner cavity of the outer fixed cylinder 11. One of the ports of the hot water outlet pipe 32 passes through the outer fixed cylinder 11 and is connected to the inner cavity of the inner fixed cylinder 12.

[0048] The inner bottom of the heating tank 4 is evenly distributed along the circumferential direction with a plurality of drive shafts 18 that are arranged to rotate along the plumb line. The plurality of drive shafts 18 and the plurality of heating cylinders 22 are alternately arranged along the circumferential direction. The outer wall of the drive shaft 18 is evenly distributed along the circumferential direction with a plurality of stirring blades 17.

[0049] When the filtrate in the heating tank 4 is heated, the hot water of the hot water unit enters the outer fixed cylinder 11 through the hot water inlet pipe 30, the hot water in the outer fixed cylinder 11 enters the plurality of heating cylinders 22 through the plurality of lower connecting pipes 29 respectively, the hot water in the heating cylinder 22 enters the inner fixed cylinder 12 through the upper connecting pipe 20, and is discharged to the hot water unit through the hot water outlet pipe 32 for reheating. During the circulation of the hot water, the driving shaft 18 drives the stirring blade 17 to rotate, thereby stirring the filtrate in the heating tank 4. At the same time, the decompression assembly 5 drives the driving rod 23 to rise and fall, thereby driving the liquid pumping piston 15 to slide vertically. When the liquid pumping piston 15 slides upward, the filtrate at the bottom of the heating tank 4 enters the liquid pumping cylinder 16 in one direction through the plurality of liquid inlet branches 13, the liquid inlet main pipe 25 and the liquid inlet one-way valve 26, and the liquid pumping piston 1 When sliding downward, the filtrate in the liquid pumping cylinder 16 enters the plurality of liquid discharge pipes 21 in one direction through the plurality of liquid discharge pipes 27 and the liquid discharge one-way valves 28, and the filtrate in the liquid discharge pipes 21 flows upward and is discharged through the upper ports thereof, thereby making the filtrate in the heating tank 4 flow vertically, and under the stirring of the stirring blades 17, the filtrate at all positions in the heating tank 4 can contact and exchange heat with the heating cylinder 22 and the heat-conducting fins 24, thereby making it possible to evenly heat the filtrate in the heating tank 4, and when the filtrate passes through the liquid discharge pipes 21, the hot water in the heating cylinder 22 can also heat it, further accelerating the heating speed of the filtrate, realizing the function of evenly heating the filtrate, and the fast heating speed of the filtrate shortens the time required for the filtrate to reach the target temperature, thereby greatly improving the heating efficiency of the filtrate;

[0050] The decompression assembly 5 can reciprocate to provide a low-pressure environment in the heating tank 4, thereby accelerating the evaporation rate of the liquid diethyl malonate;

[0051] The boosting component 8 can be used to intermittently transport vaporized diethyl malonate to a number of condensing components 7, and can also be used to boost the pressure on the diethyl malonate entering the condensing component 7. The pressurized diethyl malonate can be condensed by the condensing component 7. The boosting component 8 cooperates with the several condensing components 7 to accelerate the condensation rate of diethyl malonate and improve the distillation efficiency.

[0052] The decompression assembly 5 includes a decompression circular plate 33 which is vertically slidably sealed to the inner wall of the heating tank 4. The top of the driving rod 23 is fixedly connected to the bottom of the decompression circular plate 33. The top of the decompression circular plate 33 is uniformly provided with a plurality of slide grooves 39 in the circumferential direction. The bottom of the slide groove 39 is provided with a sliding plate 42 in a radially slidably sealed manner along the decompression circular plate 33. The bottom of the slide groove 39 is penetrated with an exhaust hole 40. The top of the decompression circular plate 33 is coaxially fixedly connected with a support cylinder 35. The support cylinder 35 is coaxially provided with a driving circular plate 38 which is slidably arranged. The outer wall of the support cylinder 35 is uniformly provided with a plurality of avoidance grooves 37 which are penetrated and arranged. The side wall of the driving circular plate 38 is uniformly provided with a plurality of swing plates 41 which are hinged thereto in the circumferential direction. One end of the plurality of swing plates 41 respectively passes through the plurality of avoidance grooves 37 and extends to the outside, and is correspondingly hinged to the plurality of sliding plates 42.

[0053] When the pressure reducing circular plate 33 slides downward from the highest position, the driving circular plate 38 rises to the highest position. With the cooperation of the swing plate 41, the sliding plate 42 slides inward and opens the exhaust hole 40. When the pressure reducing circular plate 33 slides downward to be close to the liquid surface of the filtrate, the vaporized diethyl malonate enters the upper part of the pressure reducing circular plate 33 through the exhaust hole 40 and enters the boosting assembly 8.

[0054] When the pressure reducing circular plate 33 slides upward from the lowest position, the driving circular plate 38 descends to the lowest position. With the cooperation of the swing plate 41, the sliding plate 42 slides outward and closes the exhaust hole 40. During the process of the pressure reducing circular plate 33 sliding upward to the highest position, the air pressure in the area below the pressure reducing circular plate 33 of the heating tank 4 decreases. During the process of the pressure reducing circular plate 33 rising and falling, it can reciprocate to provide a low-pressure environment for the heating tank 4, thereby accelerating the evaporation rate of liquid diethyl malonate.

[0055] The condensation assembly 7 includes a support plate 51 vertically fixedly arranged on the top of the support base 1, and a vertically arranged condensation tank 58 is provided at the end of the support plate 51 for vertical reciprocating sliding. A fixed condensation cylinder 48 is coaxially arranged inside the condensation tank 58, and the outer wall of the condensation cylinder 48 is slidably and sealedly connected to the inner wall of the condensation tank 58. An outer fixed tube 44 is coaxially fixedly connected to the inner top of the condensation cylinder 48, and an inner fixed tube 43 is coaxially arranged inside the outer fixed tube 44. The top of the inner fixed tube 43 is fixedly connected to the inner top of the condensation cylinder 48. The bottoms of the outer fixed tube 44 and the inner fixed tube 43 both pass downward through the condensation cylinder 48 and the condensation tank 58 in sequence, and are fixedly connected to the top of the support base 1. The outer fixed tube 44 is slidably and sealedly connected to the condensation tank 58, and the outer wall of the outer fixed tube 44 is located at the lower part of the condensation cylinder 48 and is circumferentially uniformly provided with a plurality of lower passages connected to its inner cavity. Liquid pipe 49, the outer wall of the inner fixed pipe 43 is located at the upper position in the condensing tube 48, and a plurality of upper liquid pipes 47 connected to its inner cavity are evenly distributed along the circumferential direction, and one of the ports of the upper liquid pipe 47 passes through the outer fixed pipe 44 and extends into the condensing tube 48. A plurality of vertically arranged condensing tubes 46 are evenly distributed along the circumferential direction in the condensing tube 48, and the top and bottom of the condensing tube 46 extend upward and downward to the outside of the condensing tube 48 respectively. The outer wall of the condensing tube 46 is located in the condensing tube 48 and is fixedly sleeved with a plurality of heat exchange fins 45 evenly distributed along its axial direction. A cold water inlet pipe 59 and a cold water outlet pipe 60 connected to the chiller are provided below the condensing tank 58, and one of the ports of the cold water inlet pipe 59 is connected to the inner cavity of the outer fixed pipe 44, and one of the ports of the cold water outlet pipe 60 passes through the outer fixed pipe 44 and is connected to the inner cavity of the inner fixed pipe 43.

[0056] A lifting circular plate 53 is coaxially provided in the condensing tank 58 at a position above the condensing cylinder 48 and is slidably and sealably connected thereto. Two limiting cylinders 55 are vertically fixedly provided at the inner top of the condensing tank 58. Two vertically arranged lifting rods 54 are fixedly connected to the top of the lifting circular plate 53. The tops of the two lifting rods 54 extend into the two limiting cylinders 55 respectively and are correspondingly slidably connected to the two limiting cylinders 55. Compression springs 56 are provided in the limiting cylinders 55. The two ends of the compression springs 56 are correspondingly abutted against the inner tops of the lifting rods 54 and the limiting cylinders 55. A through hole 57 is penetrated through the top of the condensing tank 58.

[0057] A drain valve 50 connected to the inner cavity of the condensation tank 58 is fixedly provided at the bottom thereof;

[0058] The vaporized diethyl malonate enters one of the condensing tanks 58 through the booster assembly 8. As the content of diethyl malonate in the condensing tank 58 increases, the internal air pressure of the condensing tank 58 increases, the lifting circular plate 53 slides upward, and the compression spring 56 is compressed. When the content of diethyl malonate in the condensing tank 58 reaches a certain value, the booster assembly 8 transports the vaporized diethyl malonate to the remaining condensing tanks 58.

[0059] The cold water of the chiller enters the outer fixed tube 44 through the cold water inlet pipe 59, and enters the condenser tube 48 through a plurality of lower liquid pipes 49. The cold water in the condenser tube 48 enters the inner fixed tube 43 through a plurality of upper liquid pipes 47, and is discharged to the chiller through the cold water outlet pipe 60 for cooling. In the process of circulating the cold water, the condenser tube 46 can be continuously cooled with the cooperation of the heat exchange fins 45. The condenser tank 58 to which diethyl malonate is added slides vertically back and forth, and the diethyl malonate in the condenser tank 58 is cooled back and forth through the condenser tube 46. The condensed diethyl malonate is collected at the bottom of the condenser tank 58. The boiling point of diethyl malonate can be increased by pressurization, thereby reducing the difference between the actual temperature and the boiling point of the vaporized diethyl malonate, thereby accelerating the condensation rate of diethyl malonate and improving the distillation efficiency.

[0060] The boosting assembly 8 includes a boosting tank 62 fixedly arranged vertically, a boosting piston 63 with a sliding seal is coaxially arranged in the boosting tank 62, a follower rod 69 with a vertical reciprocating sliding arrangement is fixedly connected to the bottom of the boosting piston 63, the bottom end of the follower rod 69 extends downward through the boosting tank 62 to the outside, and is slidably connected to the boosting tank 62, an intake pipe 67 connected to its inner cavity is coaxially fixedly connected to the top of the boosting tank 62, an intake check valve 68 is arranged on the intake pipe 67, one of the ports of the intake pipe 67 is connected to the inner cavity of the heating tank 4, a plurality of exhaust pipes 66 connected to its inner cavity are uniformly distributed along the circumferential direction on the top of the boosting tank 62, an exhaust valve 65 and an exhaust check valve 64 are arranged on the exhaust pipe 66, and one end of the plurality of exhaust pipes 66 is correspondingly connected to the inner cavity of the plurality of condensing tanks 58;

[0061] When the boost piston 63 slides downward, the vaporized diethyl malonate in the heating tank 4 enters the boost tank 62 in one direction through the intake pipe 67 and the intake check valve 68. When the boost piston 63 slides upward, the diethyl malonate in the boost tank 62 enters the condensing tank 58 in one direction through the exhaust pipe 66 and the exhaust check valve 64. The connectivity between several condensing tanks 58 and the boost tank 62 can be adjusted by controlling the opening and closing of the exhaust valve 65.

[0062] The bottom of the booster tank 62 is fixedly connected to two vertically arranged support vertical plates 70, the bottom of the support vertical plates 70 is fixedly connected to the top of the support base 1, a support cross plate 19 is horizontally arranged between the two support vertical plates 70, the opposite side walls of the support cross plate 19 are fixedly connected to the two support vertical plates 70, and a control reciprocating telescopic cylinder 61 is fixedly arranged on the top of the support cross plate 19, and the telescopic end of the control reciprocating telescopic cylinder 61 is fixedly connected to the driven rod 69.

[0063] A plurality of driving motors 10 are fixedly disposed at the bottom of the heating tank 4 , and output ends of the plurality of driving motors 10 all pass through the heating tank 4 and are fixedly connected to a plurality of driving shafts 18 correspondingly.

[0064] A rotatably arranged single-thread screw 34 is coaxially disposed on the inner top of the support tube 35 . The bottom end of the single-thread screw 34 passes through the driving circular plate 38 and is rotatably connected to the inner bottom of the support tube 35 . The single-thread screw 34 is threadedly connected to the driving circular plate 38 .

[0065] A servo motor 36 is fixedly provided on the top of the support tube 35 , and an output end of the servo motor 36 passes through the support tube 35 and is fixedly connected to the single-thread screw 34 .

[0066] Two built-in telescopic cylinders 6 are fixedly provided on the inner top of the heating tank 4 , and the telescopic ends of the two built-in telescopic cylinders 6 are fixedly connected to the pressure reducing circular plate 33 .

[0067] The condensation tank 58 is slidably connected to the support plate 51 through the fixed plate 52 , and two driving reciprocating telescopic cylinders 9 are fixedly provided at the top of the support base 1 below the condensation tank 58 , and the telescopic ends of the driving reciprocating telescopic cylinders 9 are fixedly connected to the condensation tank 58 .

[0068] The working principle of this device is:

[0069] Filtrate is added to the heating tank 4 through the feed valve 3. When the filtrate in the heating tank 4 is heated, the hot water of the hot water unit enters the outer fixed cylinder 11 through the hot water inlet pipe 30, and enters into the plurality of heating cylinders 22 through the plurality of lower connecting pipes 29 respectively. The hot water in the heating cylinder 22 enters the inner fixed cylinder 12 through the upper connecting pipe 20, and is discharged to the hot water unit through the hot water outlet pipe 32 for reheating. During the circulation of hot water, the driving motor 10 drives the driving shaft 18 and the stirring blade 17 to rotate, thereby stirring the filtrate in the heating tank 4. At the same time, the built-in telescopic cylinder 6 drives the pressure reducing circular plate 33 to rise and fall, thereby driving the driving rod 23 and the liquid pumping piston 15 to slide vertically. When the liquid pumping piston 15 slides upward, the filtrate at the bottom of the heating tank 4 enters in one direction through the plurality of liquid inlet branches 13, the liquid inlet main pipe 25 and the liquid inlet check valve 26. When the liquid pumping piston 15 slides downward, the filtrate in the liquid pumping cylinder 16 enters the plurality of liquid discharge pipes 21 in one direction through the plurality of liquid discharge pipes 27 and the liquid discharge one-way valve 28, and the filtrate in the liquid discharge pipe 21 flows upward and is discharged through the upper port thereof, thereby making the filtrate in the heating tank 4 flow vertically, and under the stirring of the stirring blade 17, the filtrate at all positions in the heating tank 4 can contact and exchange heat with the heating cylinder 22 and the heat-conducting fins 24, thereby being able to evenly heat the filtrate in the heating tank 4, and when the filtrate passes through the liquid discharge pipe 21, the hot water in the heating cylinder 22 can also heat it, further accelerating the heating speed of the filtrate, realizing the function of evenly heating the filtrate, and the fast heating speed of the filtrate shortens the time required for the filtrate to reach the target temperature, thereby greatly improving the heating efficiency of the filtrate;

[0070] The built-in telescopic cylinder 6 drives the pressure reducing circular plate 33 to slide vertically. When the pressure reducing circular plate 33 slides downward from the highest position, the servo motor 36 drives the single-thread screw 34 to rotate, thereby controlling the driving circular plate 38 to slide upward. With the cooperation of the swing plate 41, the sliding plate 42 slides inward and opens the exhaust hole 40. In the process of the pressure reducing circular plate 33 sliding downward to be close to the liquid surface of the filtrate, the vaporized diethyl malonate in the heating tank 4 enters above the pressure reducing circular plate 33 through the exhaust hole 40. When the pressure reducing circular plate 33 slides upward from the lowest position, the servo motor 36 drives the single-thread screw 34 to rotate, thereby controlling the driving circular plate 38 to slide downward. With the cooperation of the swing plate 41, the sliding plate 42 slides outward and closes the exhaust hole 40. In the process of the pressure reducing circular plate 33 sliding upward to the highest position, the air pressure in the area below the pressure reducing circular plate 33 of the heating tank 4 is reduced. In the process of the pressure reducing circular plate 33 rising and falling, it can reciprocate to provide a low-pressure environment for the heating tank 4, thereby accelerating the evaporation rate of the liquid diethyl malonate.

[0071] When one of the exhaust valves 65 is opened, the boost tank 62 is connected to one of the condensing tanks 58, and the reciprocating telescopic cylinder 61 is controlled to drive the driven rod 69 and the boost piston 63 to slide back and forth vertically. When the boost piston 63 slides downward, the vaporized diethyl malonate in the area above the pressure reducing circular plate 33 in the heating tank 4 enters the boost tank 62 in one direction through the intake pipe 67 and the intake check valve 68. When the boost piston 63 slides upward, the diethyl malonate in the boost tank 62 enters the condensing tank 58 in one direction through the exhaust pipe 66 and the exhaust check valve 64. As the content of diethyl malonate in the condensing tank 58 increases, the internal air pressure of the condensing tank 58 increases, the lifting circular plate 53 slides upward, and the compression spring 56 is compressed. When the content of diethyl malonate in the condensing tank 58 reaches a certain value, the vaporized diethyl malonate can be transported to the remaining condensing tanks 58 by controlling the opening and closing of other exhaust valves 65, and the cooling of the chiller Water enters the outer fixed tube 44 through the cold water inlet pipe 59, and enters the condenser tube 48 through a plurality of lower liquid pipes 49. The cold water in the condenser tube 48 enters the inner fixed tube 43 through a plurality of upper liquid pipes 47, and is discharged to the chiller through the cold water outlet pipe 60 for recooling. In the process of circulating, the cold water can continuously cool the condenser tube 46 with the cooperation of the heat exchange fins 45, and drives the reciprocating telescopic cylinder 9 to drive the condenser tank 58 to which diethyl malonate is added to slide vertically reciprocatingly. The diethyl malonate in the condenser tank 58 is cooled by reciprocating through the condenser tube 46. The condensed diethyl malonate is collected at the bottom of the condenser tank 58. The boiling point of diethyl malonate can be increased by pressurization, thereby reducing the difference between the actual temperature and the boiling point of the vaporized diethyl malonate. At the same time, with the cooperation of a plurality of condenser tanks 58, the condensation speed of diethyl malonate is greatly accelerated, thereby improving the distillation efficiency.

[0072] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein by equivalents. These modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present invention, and they should all be included in the scope of the claims and specification of the present invention.

Claims

1. A distillation purification device for the preparation of diethyl malonate, characterized in that: The invention comprises a support base (1), a heating tank (4) is vertically fixedly arranged on the top of the support base (1), a heating component (2) is arranged on the inner bottom of the heating tank (4), a pressure reducing component (5) is arranged in the heating tank (4) at a position above the heating component (2), a pressurizing component (8) and a plurality of condensing components (7) are also arranged on the top of the support base (1), the plurality of condensing components (7) are evenly distributed around the pressurizing component (8) along the circumferential direction, the plurality of condensing components (7) are connected to the inner cavity of the heating tank (4) through the pressurizing component (8), a feed valve (3) connected to the inner cavity of the heating tank (4) is fixedly arranged on the outer wall of the heating tank (4) at a position between the heating component (2) and the pressure reducing component (5), and a discharge valve (31) connected to the inner cavity of the heating tank (4) is fixedly arranged at the bottom of the heating tank (4); The heating assembly (2) comprises an outer fixed cylinder (11) vertically penetrating the inner bottom of the heating tank (4); an inner fixed cylinder (12) with an open bottom is coaxially arranged inside the outer fixed cylinder (11); the bottom of the inner fixed cylinder (12) is fixedly connected to the inner bottom of the outer fixed cylinder (11); the top of the inner fixed cylinder (12) extends upward through the outer fixed cylinder (11) into the heating tank (4); a liquid extraction cylinder (16) with openings at both ends is coaxially arranged inside the inner fixed cylinder (12); the top and bottom of the liquid extraction cylinder (16) correspond to the inner fixed cylinder (12). The inner top of the outer fixed cylinder (11) is fixedly connected to the inner bottom of the outer fixed cylinder (11); the inner wall of the liquid pumping cylinder (16) is coaxially fixedly connected to a partition (14) at a position located inside the heating tank (4); a liquid pumping piston (15) is coaxially provided at a position above the partition (14) inside the liquid pumping cylinder (16) and is slidably and sealedly connected to the inner wall thereof; a driving rod (23) is fixedly connected to the top of the liquid pumping piston (15); the top of the driving rod (23) passes upward through the inner fixed cylinder (12) and is connected to the decompression assembly (5); the driving rod (23) is slidably connected to the inner fixed cylinder (12); The inner bottom of the heating tank (4) is uniformly distributed along the circumferential direction with a plurality of vertically fixed heating tubes (22); the upper outer wall and the lower outer wall of the heating tube (22) are respectively fixedly connected with an upper connecting tube (20) and a lower connecting tube (29) which are connected with the inner cavity thereof; one of the ports of the upper connecting tube (20) is connected with the inner cavity of the inner fixed tube (12); one of the ports of the lower connecting tube (29) is connected with the inner cavity of the outer fixed tube (11); the outer wall of the heating tube (22) is fixedly sleeved with a plurality of heat-conducting fins (24) which are uniformly distributed along the axial direction thereof; the inner bottom of the heating tube (22) is coaxially fixedly connected with a drain pipe (21); the upper port of the drain pipe (21) passes through the heating tube (22) upward and extends to the outside; the bottom of the partition (14) is provided with a plurality of heat-conducting fins (24) which are uniformly distributed along the axial direction thereof; A liquid inlet main pipe (25) is coaxially fixedly connected to the main part of the liquid inlet pipe (25), and a liquid inlet check valve (26) is provided on the main liquid inlet pipe (25). A plurality of liquid inlet branch pipes (13) connected to the lower end thereof are evenly distributed along the circumferential direction below the main liquid inlet pipe (25), and one end of the liquid inlet branch pipe (13) passes through the liquid extraction cylinder (16), the inner fixed cylinder (12) and the outer fixed cylinder (11) in sequence and extends to the inner bottom of the heating tank (4). A plurality of liquid outlet pipes (27) are evenly distributed along the circumferential direction at the bottom of the partition plate (14), and a liquid outlet check valve (28) is provided on the liquid outlet pipe (27). One end of each of the plurality of liquid outlet pipes (27) passes through the liquid extraction cylinder (16) and the inner fixed cylinder (12) in sequence, and respectively coaxially passes through a plurality of lower connecting pipes (29) and is connected to a plurality of liquid discharge pipes (21) accordingly. A hot water inlet pipe (30) and a hot water outlet pipe (32) connected to the hot water unit are provided below the heating tank (4); one of the ports of the hot water inlet pipe (30) is connected to the inner cavity of the outer fixed cylinder (11); one of the ports of the hot water outlet pipe (32) passes through the outer fixed cylinder (11) and is connected to the inner cavity of the inner fixed cylinder (12); The inner bottom of the heating tank (4) is evenly distributed along the circumferential direction with a plurality of drive shafts (18) arranged to rotate along a vertical line, the plurality of drive shafts (18) and the plurality of heating cylinders (22) are alternately arranged along the circumferential direction, and the outer wall of the drive shaft (18) is evenly distributed along the circumferential direction with a plurality of stirring blades (17).

2. The rectification and purification device for the preparation of diethyl malonate according to claim 1, characterized in that: The decompression assembly (5) comprises a decompression circular plate (33) vertically slidably sealed to the inner wall of the heating tank (4); the top of the driving rod (23) is fixedly connected to the bottom of the decompression circular plate (33); the top of the decompression circular plate (33) is uniformly provided with a plurality of slide grooves (39) along the circumferential direction; the bottom of the slide groove (39) is provided with a sliding plate (42) along the radial slidably sealed path of the decompression circular plate (33); the bottom of the slide groove (39) is penetrated by an exhaust hole (40); A support cylinder (35) is coaxially fixedly connected to the top, a driving circular plate (38) is coaxially provided inside the support cylinder (35) and is slidably arranged, a plurality of escape grooves (37) are evenly distributed along the circumferential direction on the outer wall of the support cylinder (35), a plurality of swing plates (41) hingedly connected to the driving circular plate (38) are evenly distributed along the circumferential direction on the side wall of the driving circular plate (38), one end of each of the swing plates (41) respectively passes through the plurality of escape grooves (37) and extends to the outside, and is correspondingly hinged to the plurality of sliding plates (42).

3. The distillation and purification device for preparing diethyl malonate according to claim 1, characterized in that: The condensation assembly (7) comprises a support plate (51) vertically fixedly arranged on the top of the support base (1); a vertically arranged condensation tank (58) is provided at the end of the support plate (51) for vertical reciprocating sliding; a fixedly arranged condensation cylinder (48) is coaxially arranged inside the condensation tank (58); the outer wall of the condensation cylinder (48) is slidably and sealingly connected to the inner wall of the condensation tank (58); an external fixed tube (44) is coaxially fixedly connected to the inner top of the condensation cylinder (48); the inner part of the external fixed tube (44) is coaxially fixedly connected to the inner top of the condensation cylinder (48); The shaft is provided with an inner fixed tube (43), the top of the inner fixed tube (43) is fixedly connected to the inner top of the condensing cylinder (48), the bottoms of the outer fixed tube (44) and the inner fixed tube (43) are downwardly passed through the condensing cylinder (48) and the condensing tank (58) in sequence, and are fixedly connected to the top of the supporting base (1), the outer fixed tube (44) is slidably and hermetically connected to the condensing tank (58), and the outer wall of the outer fixed tube (44) is located at a position below the inner cavity of the condensing cylinder (48) and is uniformly distributed along the circumferential direction. The outer wall of the inner fixed tube (43) is located at an upper position in the condensing cylinder (48) and is evenly distributed along the circumferential direction with a plurality of upper liquid pipes (47) connected to the inner cavity thereof. One of the ports of the upper liquid pipe (47) passes through the outer fixed tube (44) and extends into the condensing cylinder (48). The condensing cylinder (48) is evenly distributed along the circumferential direction with a plurality of vertically arranged condensing tubes (46). The top and bottom of the condensing tubes (46) extend upward and downward, respectively, to the outside of the condensing cylinder (48). The outer wall of the condenser tube (46) is fixedly mounted in a position inside the condenser tube (48) and is provided with a plurality of heat exchange fins (45) evenly distributed along its axial direction. A cold water inlet pipe (59) and a cold water outlet pipe (60) connected to the chiller are provided below the condenser tank (58). One of the ports of the cold water inlet pipe (59) is connected to the inner cavity of the outer fixed tube (44). One of the ports of the cold water outlet pipe (60) passes through the outer fixed tube (44) and is connected to the inner cavity of the inner fixed tube (43). A lifting circular plate (53) is coaxially provided in the condensing tank (58) at a position above the condensing tank (48) and is slidably and sealably connected thereto. Two limiting cylinders (55) are vertically fixedly provided at the inner top of the condensing tank (58). Two vertically arranged lifting rods (54) are fixedly connected to the top of the lifting circular plate (53). The tops of the two lifting rods (54) extend into the two limiting cylinders (55) respectively and are correspondingly slidably connected to the two limiting cylinders (55). Compression springs (56) are provided in the limiting cylinders (55). The two ends of the compression springs (56) are correspondingly abutted against the inner tops of the lifting rods (54) and the limiting cylinders (55). A through hole (57) is provided through the top of the condensing tank (58). A drain valve (50) connected to the inner cavity of the condensation tank (58) is fixedly provided at the bottom thereof.

4. The rectification and purification device for preparing diethyl malonate according to claim 3, characterized in that: The boosting assembly (8) comprises a boosting tank (62) which is fixedly arranged vertically, a boosting piston (63) which is coaxially arranged in the boosting tank (62) and is provided with a sliding seal, a driven rod (69) which is fixedly arranged to slide vertically and reciprocally is fixedly connected to the bottom of the boosting piston (63), the bottom end of the driven rod (69) passes through the boosting tank (62) downward and extends to the outside, and is slidably connected to the boosting tank (62), and a boosting piston (63) which is coaxially fixedly connected to the top of the boosting tank (62) and is in communication with its inner cavity. An air intake pipe (67) is provided on the air intake pipe (67), an air intake check valve (68) is provided on the air intake pipe (67), one of the ports of the air intake pipe (67) is in communication with the inner cavity of the heating tank (4), a plurality of exhaust pipes (66) in communication with the inner cavity of the boost tank (62) are evenly distributed along the circumferential direction on the top of the boost tank (62), the exhaust pipes (66) are each provided with an exhaust valve (65) and an exhaust check valve (64), and one end of the plurality of exhaust pipes (66) is correspondingly in communication with the inner cavities of the plurality of condensing tanks (58).

5. The distillation and purification device for preparing diethyl malonate according to claim 4, characterized in that: The bottom of the boost tank (62) is fixedly connected to two vertically arranged support vertical plates (70), the bottom of the support vertical plates (70) is fixedly connected to the top of the support base (1), a support cross plate (19) is horizontally arranged between the two support vertical plates (70), the opposite side walls of the support cross plate (19) are fixedly connected to the two support vertical plates (70), and a control reciprocating telescopic cylinder (61) is fixedly arranged on the top of the support cross plate (19), and the telescopic end of the control reciprocating telescopic cylinder (61) is fixedly connected to the driven rod (69).

6. The distillation purification device for preparing diethyl malonate according to claim 1, characterized in that: A plurality of drive motors (10) are fixedly disposed on the bottom of the heating tank (4), and output ends of the plurality of drive motors (10) all pass through the heating tank (4) and are fixedly connected to a plurality of drive shafts (18) accordingly.

7. The distillation purification device for preparing diethyl malonate according to claim 2, characterized in that: A rotatably arranged single-thread screw (34) is coaxially disposed on the inner top of the support cylinder (35); the bottom end of the single-thread screw (34) passes through a driving circular plate (38) and is rotatably connected to the inner bottom of the support cylinder (35); the single-thread screw (34) is threadedly connected to the driving circular plate (38).

8. The distillation and purification device for preparing diethyl malonate according to claim 7, characterized in that: A servo motor (36) is fixedly provided on the top of the support tube (35); an output end of the servo motor (36) passes through the support tube (35) and is fixedly connected to the single-thread screw (34).

9. The distillation purification device for preparing diethyl malonate according to claim 2, characterized in that: Two built-in telescopic cylinders (6) are fixedly provided on the inner top of the heating tank (4), and the telescopic ends of the two built-in telescopic cylinders (6) are fixedly connected to the pressure reducing circular plate (33).

10. The distillation and purification device for preparing diethyl malonate according to claim 3, characterized in that: The condensing tank (58) is slidably connected to the supporting plate (51) via a fixing plate (52); two driving reciprocating telescopic cylinders (9) are fixedly provided at a position below the condensing tank (58) on the top of the supporting base (1); and the telescopic ends of the driving reciprocating telescopic cylinders (9) are fixedly connected to the condensing tank (58).

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