A kind of diisopropyl succinate esterification reaction device and method

Abstract

The invention relates to the technical field of diisopropyl succinate preparation equipment, and in particular to a diisopropyl succinate esterification reaction device and method. A material box is arranged outside an esterification kettle, and a liquid inlet end of a first movable discharging device is located in the middle of the material box, so that part of the isopropyl alcohol in the material box is first put into the kettle for reaction. During the esterification reaction, steam on the kettle top is condensed by a condenser, and refluxes and separates water through a water separator. The condenser insulates the material box through a heat exchange pipe. When a floating plate in the water separator floats up and approaches an upper sensor, a drain pipe is triggered to drain water, until the floating plate floats down and approaches a lower sensor, triggering to stop draining water. When the floating plate floating rate drops to a predetermined amplitude, the liquid inlet ends of the first movable discharging device and the second movable discharging device are triggered to move downward synchronously, so that isopropyl alcohol is intermittently fed in batches, and the drainage frequency is adaptively adjusted, so that the esterification water separation efficiency in the esterification reaction of diisopropyl succinate is further improved, and the operation is more convenient.

Description

Technical Field

[0001] The invention relates to the technical field of diisopropyl succinate preparation equipment, and in particular to a diisopropyl succinate esterification reaction device and method. Background Art

[0002] At present, diisopropyl succinate is mainly used as a raw material for producing dipyrrolopyrrole in China. Dipyrrolopyrrole is a red high-performance organic pigment with a wide range of applications. For the preparation and production of diisopropyl succinate, the esterification reaction of maleic anhydride and isopropanol can be adopted. After all the raw materials including maleic anhydride, isopropanol, a dehydrating agent and a catalyst are added at one time, under the action of the dehydrating agent, the esterification reaction is carried out while separating water, that is, the water is separated by reflux simultaneously, and the generated water is separated, so that the reaction equilibrium moves to the direction of generating more esters, thereby improving the yield of esters. In the prior art, a conventional esterification reactor is adopted, all the raw materials are put into the reactor at one time, and a condenser is connected to the top of the reactor, and a water separator is connected to the bottom of the condenser. The dehydrating agent has a low boiling point and is easy to evaporate and evaporate in the esterification reaction in the reactor. The steam is taken out, and the steam on the top of the kettle is condensed by the condenser and refluxed through the water separator to separate the water, that is, the separated dehydrating agent is refluxed into the reactor, and the excess water is discharged. Existing Chinese patent documents such as CN109078594A discloses a 7110 methyl polyurethane curing agent reactor, CN211463119U discloses a multi-material condensate water separator for an esterification reactor, CN215312379U discloses a water separator for an esterification reactor, and CN211463120U discloses a condensate water separator for an esterification reactor, etc., all of which use similar esterification equipment and principle methods. However, it is found in actual production that the efficiency of esterification and water separation is still not high enough, and when the water separator is drained, it is necessary to manually observe the water separation interface in the water separator and drain appropriately, which is inconvenient for actual production operation and still needs to be further optimized. Summary of the invention

[0003] In view of this, the purpose of the present invention is to provide a diisopropyl succinate esterification reaction device and method to solve the problems that the efficiency of esterification and water separation in the existing diisopropyl succinate esterification reaction needs to be further improved and the water separation operation is inconvenient.

[0004] Based on the above purpose, the present invention provides a diisopropyl succinate esterification reaction device, including an esterification kettle, a condenser is externally connected to the top of the esterification kettle, and a water separator is connected to the bottom of the condenser:

[0005] A steam pipe is externally connected to the top of the esterification kettle, and the steam pipe is connected to the condenser;

[0006] A flattened material box is mounted outside the top of the esterification kettle, and a liquid filling port is connected to the top of the material box for adding isopropyl alcohol into the material box. A first movable discharger is arranged in the material box, and a liquid inlet end of the first movable discharger is located in the material box, and a liquid outlet end of the first movable discharger passes out of the material box and downwardly penetrates into the esterification kettle. A heating plate is arranged on the material box, and a heat exchange pipe is arranged in the heating plate, and the heating plate is connected to a condenser through the heat exchange pipe.

[0007] The bottom end of the water separator is connected to a drain pipe, the side end of the water separator is connected to a reflux pipe, one end of the reflux pipe is connected to the esterification kettle, a float plate is provided in the water separator, the float plate floats on the interface between the dehydrating agent and water recovered in the water separator, a second movable discharging device is provided in the water separator, the liquid inlet end of the second movable discharging device passes through the top of the float plate upward, and is connected to an upper sensor, the liquid outlet end of the second movable discharging device is fixed in the water separator and connected to the reflux pipe, a lower sensor is provided in the water separator below the upper sensor, when the float plate floats up and approaches the upper sensor, the drain pipe is triggered to start drainage, until the float plate floats down and approaches the lower sensor, the drain pipe is triggered to stop drainage, during the esterification reaction, the liquid inlet end of the first movable discharging device and the liquid inlet end of the second movable discharging device are synchronously and intermittently moved downward, so that isopropyl alcohol is intermittently added in batches, and the upper sensor is driven to move downward synchronously.

[0008] Preferably, the steam pipeline includes a first vertical pipe section connected to the top of the esterification kettle, an inclined pipe section connected to the first vertical pipe section, and a second vertical pipe section connected to the inclined pipe section, the bottom end of the second vertical pipe section is connected to the top of the water separator, and the condenser is connected to the inclined pipe section.

[0009] Preferably, the first movable discharging device comprises a vertically mounted fixed flat cylinder, the top end of which is telescopically connected to the movable flat cylinder, the top end of the fixed flat cylinder is fixedly inserted into a material box, the bottom end of the fixed flat cylinder passes out of the material box and downwardly into the esterification kettle, the liquid inlet end of the first movable discharging device is located at the top side end of the movable flat cylinder, and the liquid outlet end of the first movable discharging device is located at the bottom end of the fixed flat cylinder.

[0010] Preferably, the bottom end of the fixed flat cylinder is connected to a flat liquid outlet head, and a plurality of liquid outlet holes are arranged at intervals along the length direction of the liquid outlet end of the flat liquid outlet head for dispersing and adding isopropanol into the kettle.

[0011] Preferably, the second movable discharging device includes a vertically arranged fixed flat tube, the top end of the fixed flat tube is telescopically connected to the movable flat tube, the fixed flat tube is fixed to the inner side of the water distributor, the liquid inlet end of the second movable discharging device is located at the top side end of the movable flat tube, and the liquid outlet end of the second movable discharging device is located at the bottom side end of the fixed flat tube and is connected to the reflux pipe.

[0012] Preferably, after isopropyl alcohol is added into the esterification kettle through the material box and the first movable discharger, until the esterification reaction is completed, the movable flat cylinder and the movable flat tube continue to move downward synchronously, so that the liquid inlet end of the first movable discharger is completely inserted into the fixed flat cylinder, and the liquid inlet end of the second movable discharger is completely inserted into the fixed flat tube, which is used to close the liquid outlet of the material box and the reflux liquid outlet of the water divider.

[0013] Preferably, the top end of the movable flat cylinder is connected with a connecting rod, one end of the connecting rod passes out of the material box and downwardly penetrates into the water distributor to be connected with the top end of the movable flat tube.

[0014] Preferably, a vertical groove is opened on the inner end of the water divider, the side edge of the floating plate penetrates into the vertical groove, the lower sensor is arranged on the inner bottom end of the vertical groove, the inner side of the top end of the second movable discharger is connected with a horizontal platform, the horizontal platform penetrates into the vertical groove, and the upper sensor is arranged at the bottom end of the horizontal platform.

[0015] The present invention also provides a method for esterification of diisopropyl succinate, comprising the following steps:

[0016] A flat material box is arranged outside the top of the esterification kettle. All the isopropanol liquid required for esterification preparation is added into the material box at one time. The remaining maleic anhydride, dehydrating agent and catalyst materials are added into the esterification kettle. The liquid inlet end of the first movable discharger is located in the middle of the material box, so that part of the isopropanol in the material box is firstly fed into the kettle by the first movable discharger for reaction. During the esterification reaction, the steam at the top of the kettle is condensed by the condenser and refluxed and separated by the water separator. The condenser is connected to the heating plate at the bottom of the material box through a heat exchange pipe to keep the isopropanol in the material box warm. The floating plate always floats on the interface between the dehydrating agent and water recovered in the water separator. When the floating plate floats up and approaches the upper sensor, the drain pipe is triggered to start drainage, until the floating plate floats down and approaches the lower sensor, triggering the drain pipe to stop drainage, thereby realizing automatic drainage. By sensing that the reaction temperature in the esterification kettle rises to a preset amplitude, and by sensing that the floating rate of the floating plate drops to a predetermined amplitude through the upper sensor and the lower sensor, the liquid inlet end of the first active discharging device and the liquid inlet end of the second active discharging device are triggered to move downward synchronously, so that isopropyl alcohol is intermittently added in batches, and the drainage frequency is adaptively adjusted.

[0017] Preferably, when the esterification reaction is completed and the upper sensor and the lower sensor sense that the float plate is no longer floating, the liquid inlet end of the first movable discharging device and the liquid inlet end of the second movable discharging device are triggered to continue to move downward synchronously, so that the liquid inlet end of the first movable discharging device and the liquid inlet end of the second movable discharging device are closed, thereby facilitating the re-addition of isopropyl alcohol and the complete collection of the dehydrating agent.

[0018] The beneficial effects of the present invention are as follows: a flattened material box is arranged outside the top of the esterification kettle, and the liquid inlet end of the first movable discharger is located in the middle of the material box, so that part of the isopropyl alcohol in the material box is first fed into the kettle by the first movable discharger for reaction. During the esterification reaction, the steam on the top of the kettle is condensed by the condenser and refluxed through the water separator for water separation. The condenser is connected to the heating plate at the bottom of the material box through a heat exchange pipe to keep the isopropyl alcohol in the material box warm. The floating plate in the water separator always floats on the interface between the dehydrating agent and water recovered in the water separator. When the floating plate floats up and approaches the upper sensor, The drain pipe is triggered to start drainage until the float plate floats down and approaches the lower sensor, which triggers the drain pipe to stop drainage, thereby realizing automatic drainage. By sensing that the reaction temperature in the esterification kettle rises to a preset amplitude, and the upper sensor and the lower sensor sense that the floating rate of the float plate drops to a predetermined amplitude, the liquid inlet end of the first active discharger and the liquid inlet end of the second active discharger are triggered to move downward synchronously, so that isopropyl alcohol is intermittently added in batches, and the drainage frequency is adaptively adjusted, so as to further improve the efficiency of esterification and water separation in the esterification reaction of diisopropyl succinate, and achieve a more convenient operation. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In order to more clearly illustrate the technical solutions in the present invention or the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings in the following description are only for the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0020] Figure 1 It is a schematic diagram of the overall structure of the present invention;

[0021] Figure 2 It is a schematic structural diagram of the flat liquid discharge head of the present invention;

[0022] Figure 3 It is a structural schematic diagram of the liquid inlet end of the first movable discharging device and the liquid inlet end of the second movable discharging device of the present invention when they are in an initial neutral state;

[0023] Figure 4 It is a structural schematic diagram of the first movable discharger of the present invention;

[0024] Figure 5 It is a structural schematic diagram of the second movable discharger of the present invention;

[0025] Figure 6 to Figure 7 It is a structural schematic diagram of the liquid inlet end of the first movable discharging device and the liquid inlet end of the second movable discharging device of the present invention when they move downward synchronously and intermittently;

[0026] Figure 8 It is a structural schematic diagram of the liquid inlet end of the first movable discharging device and the liquid inlet end of the second movable discharging device of the present invention when they are synchronously moved downward and closed.

[0027] The markings in the figure are:

[0028] 1. Esterification kettle; 100. Feeding port; 200. Driving device; 300. Lifting cylinder; 2. Condenser; 3. Water distributor; 31. Drain pipe; 32. Reflux pipe; 33. Vertical groove; 4. Steam pipe; 41. First vertical pipe section; 42. Oblique pipe section; 43. Second vertical pipe section; 5. Material box; 51. Liquid feeding port; 6. First movable discharger; 61. Fixed flat cylinder; 62. Movable flat cylinder; 63. Flat liquid discharge head; 64. Liquid discharge hole; 7. Heating plate; 71. Heat exchange pipe; 8. Floating plate; 9. Second movable discharger; 91. Fixed flat tube; 92. Movable flat tube; 10. Upper sensor; 11. Lower sensor; 12. Connecting rod; 13. Horizontal platform; 14. Telescopic thin rod; 15. Inner tube. DETAILED DESCRIPTION

[0029] In order to make the objectives, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with specific embodiments.

[0030] It should be noted that, unless otherwise defined, the technical terms or scientific terms used in the present invention should be understood by people with ordinary skills in the field to which the present invention belongs. The "first", "second" and similar words used in the present invention do not indicate any order, quantity or importance, but are only used to distinguish different components. "Include" or "comprise" and similar words mean that the elements or objects appearing before the word include the elements or objects listed after the word and their equivalents, without excluding other elements or objects. "Connect" or "connected" and similar words are not limited to physical or mechanical connections, but may include electrical connections, whether direct or indirect. "Up", "down", "left", "right" and the like are only used to indicate relative positional relationships. When the absolute position of the described object changes, the relative positional relationship may also change accordingly.

[0031] like Figure 1 , Figure 2 , Figure 3 , Figure 4 , Figure 5As shown, a diisopropyl succinate esterification reaction device comprises an esterification kettle 1, a condenser 2 is externally connected to the top of the esterification kettle 1, and a water separator 3 is connected to the bottom of the condenser 2. When the esterification reaction is carried out in the esterification kettle 1, the steam on the top of the kettle is condensed through the condenser 2 and refluxed through the water separator 3. A steam pipe 4 is externally connected to the top of the esterification kettle 1, and the steam pipe 4 is connected to the condenser 2. A flat material box 5 is mounted outside the top of the esterification kettle 1, and the material box 5 is connected to the bottom of the condenser 2. The top of the box 5 is connected with a liquid adding port 51 for adding isopropanol into the box 5. A first movable discharger 6 is arranged in the box 5. The liquid inlet end of the first movable discharger 6 is located in the box 5. The liquid outlet end of the first movable discharger 6 passes out of the box 5 and goes downward into the esterification kettle 1. A heating plate 7 is arranged on the box 5. A heat exchange pipe 71 is arranged in the heating plate 7 and is connected to the condenser 2 through the heat exchange pipe 71. A drain pipe 31 is connected to the bottom end of the water separator 3. A reflux pipe 32 is connected to the side end of the water separator 3, one end of the reflux pipe 32 is connected to the esterification kettle 1, a floating plate 8 is provided in the water separator 3, the floating plate 8 floats on the interface between the dehydrating agent and water recovered in the water separator 3, a second movable discharging device 9 is provided in the water separator 3, the liquid inlet end of the second movable discharging device 9 passes through the top of the floating plate 8 upward, and is connected to an upper sensor 10, the liquid outlet end of the second movable discharging device 9 is fixed in the water separator 3 and connected to the reflux pipe 32, a lower sensor 11 is provided in the water separator 3 below the upper sensor 10, when the floating plate 8 floats up and approaches the upper sensor 10, the drain pipe 31 is triggered to start drainage, until the floating plate 8 floats down and approaches the lower sensor 11, the drain pipe 31 is triggered to stop drainage, during the esterification reaction, the liquid inlet end of the first movable discharging device 6 and the liquid inlet end of the second movable discharging device 9 are synchronously and intermittently moved downward, so that isopropyl alcohol is intermittently added in batches, and the upper sensor 10 is driven to move downward synchronously.

[0032] The present invention is based on the existing diisopropyl succinate esterification reactor and condensation water separation device, comprising an esterification kettle 1, a condenser 2 is externally connected to the top of the esterification kettle 1, and a water separator 3 is connected to the bottom of the condenser 2. When the esterification reaction is carried out in the existing esterification kettle 1, all raw materials including maleic anhydride, isopropanol, a dehydrating agent and a catalyst are added at one time, and the reaction temperature is about 85°C. Since the boiling point of the dehydrating agent is relatively low, it is easy to evaporate and bring out water vapor during the esterification reaction in the kettle. The steam on the top of the kettle is condensed by the condenser 2. , and refluxes through the water separator 3 for water separation. The condensed water, dehydrating agent and a small amount of excess isopropanol are collected in the water separator 3. The dehydrating agent is insoluble in water and has a lower density than water. Therefore, it naturally precipitates in the water separator 3 to form a clear oil-water interface. The dehydrating agent refluxes into the esterification kettle 1 through the upper part of the water separator 3 to continue to participate in dehydration. The isopropanol is dissolved in water and discharged from the bottom of the water separator 3 along with the water. The discharged water can be recycled by distillation and other means to recover the isopropanol therein, thereby realizing the reaction preparation process of esterification and reflux water separation.

[0033] In this regard, a steam pipe 4 is externally connected to the top of the esterification kettle 1, and the steam pipe 4 is connected to the condenser 2. Specifically, the steam pipe 4 includes a first vertical pipe section 41 connected to the top of the esterification kettle 1, an inclined pipe section 42 connected to the first vertical pipe section 41, and a second vertical pipe section 43 connected to the inclined pipe section 42. The bottom end of the second vertical pipe section 43 is connected to the top of the water separator 3. The condenser 2 is connected to the inclined pipe section 42, and the inclined pipe section 42 is arranged to be inclined downward to form a Figure 1 The shape of the steam pipe 4 shown is conducive to the collection, full condensation and reflux of steam. The condenser 2 adopts a cylindrical structure design and is connected to the inclined pipe section 42. The outer wall of the condenser 2 is wound with a condensation pipe, which can be spirally wound on the outer wall of the inclined pipe section 42. A cooling medium circulates in the condensation pipe for heat exchange to condense the steam in the inclined pipe section 42 into liquid and flow into the water separator 3. A flat material box 5 is mounted outside the top of the esterification kettle 1, and a liquid filling port is connected to the top of the material box 5. 51, used to add all the isopropanol liquid required for one-time esterification preparation into the material box 5, the esterification kettle 1 is also provided with a feeding port 100, used to add other materials required for esterification preparation, the material box 5 is provided with a heating plate 7, the heating plate 7 is provided with a heat exchange pipe 71, and is connected to the condenser 2 through the heat exchange pipe 71. Specifically, the heating plate 7 can be attached to the bottom end surface of the material box 5, and the heat exchange pipe 71 can be attached to the bottom end surface of the material box 5 in a serpentine shape to fully exchange heat with the material box 5. Specifically, as Figure 1 As shown, the refrigerant feed end of the condensing pipe of the condenser 2 is at the upper position, and the refrigerant discharge end of the condensing pipe of the condenser 2 is at the lower position, and is connected to the refrigerant feed end of the heat exchange pipe 71, so that the refrigerant becomes hot after heat exchange through the steam pipe 4, and the residual temperature is used to keep the isopropanol in the material box 5 warm, which is beneficial for its efficient participation in the esterification reaction after feeding. The refrigerant is cooled after heat exchange through the material box 5, and then discharged from the refrigerant discharge end of the heat exchange pipe 71 and further actively cooled, and then recycled to the condenser 2 for condensation, thereby realizing an efficient circulation heat exchange solution;

[0034] At the same time, a first movable discharger 6 is provided in the material box 5, the liquid inlet end of the first movable discharger 6 is located in the material box 5, the liquid outlet end of the first movable discharger 6 passes out of the material box 5, and passes downward into the esterification kettle 1, the bottom end of the water divider 3 is connected to a drain pipe 31, the side end of the water divider 3 is connected to a reflux pipe 32, one end of the reflux pipe 32 is connected to the esterification kettle 1 for reflux water separation, and a floating plate 8 is provided in the water divider 3. The floating plate 8 adopts a hollow structure design with multiple holes and is made of a material with a density between water and dehydrating agent, so that the floating plate 8 always floats between the dehydrating agent and water recovered in the water divider 3. On the dividing interface, a second movable discharger 9 is provided in the water divider 3, the liquid inlet end of the second movable discharger 9 passes through the top of the floating plate 8 upward, and is connected to an upper sensor 10, the liquid outlet end of the second movable discharger 9 is fixedly arranged in the water divider 3, and is connected to the reflux pipe 32, and a lower sensor 11 is provided correspondingly below the upper sensor 10 in the water divider 3. Specifically, the upper sensor 10 and the lower sensor 11 can adopt existing conventional waterproof distance sensors, ultrasonic sensors, touch sensors and other components to sense the distance between the floating plate 8. During the esterification reaction, the drain pipe 31 is in In the initial default closed state, the liquid inlet end of the first movable discharger 6 and the liquid inlet end of the second movable discharger 9 are in the initial middle state, that is, the liquid inlet end of the second movable discharger 9 is in the middle position in the water separator 3, and the liquid inlet end of the first movable discharger 6 is in the middle position in the material box 5, so that about 50% of the total amount of isopropanol in the material box 5 is first fed into the kettle by the first movable discharger 6 for reaction. During the reaction, as water and dehydrating agent are continuously collected in the water separator 3, as the water level rises, the float plate 8 moves up, but affected by the position of the upper sensor 10, the float plate 8 cannot move up more than the second movable discharger 9. At the liquid inlet end, the dehydrating agent always flows back into the kettle along the liquid inlet end of the second movable discharging device 9 and the reflux pipe 32, and the height of the liquid inlet end of the second movable discharging device 9 remains unchanged during the upward movement of the floating plate 8, so that more and more dehydrating agent is refluxed, until the floating plate 8 floats up and approaches the upper sensor 10, triggering the drain pipe 31 to start draining, and the floating plate 8 begins to move down, until the floating plate 8 floats down and approaches the lower sensor 11, triggering the drain pipe 31 to stop draining. During the esterification reaction, the liquid inlet end of the first movable discharging device 6 and the liquid inlet end of the second movable discharging device 9 move down synchronously and intermittently, so that isopropyl alcohol can be added intermittently in batches. Specifically, Figure 1 , Figure 3 As shown, when the liquid inlet end of the first movable discharger 6 and the liquid inlet end of the second movable discharger 9 are in the initial middle state, about 50% of the total amount of isopropanol in the material box 5 is first fed into the kettle by the first movable discharger 6 for reaction. Since the amount of isopropanol in the kettle is not much, the reaction temperature in the kettle can reach a higher temperature of about 92-98°C. After a period of reaction and water separation, the amount of water separation will be significantly reduced and the temperature in the kettle will rise to about 100-105°C, triggering the liquid inlet end of the first movable discharger 6 and the liquid inlet end of the second movable discharger 9 to continue to move downward synchronously, as shown in FIG. Figure 6As shown, about 25% of the total amount of isopropanol in the material box 5 is then added to the kettle, and the reflux water is continued. After a period of water separation, as the amount of water separation is significantly reduced and the temperature in the kettle rises to about 110-115°C, the liquid inlet end of the first movable discharger 6 and the liquid inlet end of the second movable discharger 9 continue to move downward synchronously, as shown in FIG. Figure 7 As shown, the remaining 25% or so of isopropanol is added, and reflux and water separation are continued until no water is discharged, and the esterification is completed. Compared with the traditional process in which isopropanol is added to the reaction all at once, the reaction temperature in the kettle is about 80-90°C. Adding isopropanol in small amounts in batches can increase the reaction temperature, accelerate the reaction rate, shorten the time, reduce energy consumption, increase the profit, and help further improve the esterification efficiency. The water discharge of the water separator 3 is automatically controlled by the upper sensor 10 and the lower sensor 11, and the operation is more convenient. The reaction temperature can be monitored in real time by the thermometer in the kettle. By sensing the rise in reaction temperature and the obvious decrease in the floating rate of the floating plate 8 sensed by the upper sensor 10 and the lower sensor 11, it means that the water separation amount is significantly reduced, and the triggering The liquid inlet end of the first movable discharger 6 and the liquid inlet end of the second movable discharger 9 continue to move downward synchronously to realize automatic feeding of isopropyl alcohol. At the same time, after each feeding of isopropyl alcohol, the reaction is further deepened, and the water separation amount is continuously reduced. Since the liquid inlet end of the second movable discharger 9 moves downward synchronously, the frequency of controlling the floating plate 8 to float close to the upper sensor 10 increases, which is beneficial to stirring the water distributor 3 to divide water, and promoting the drainage frequency of the drain pipe 31, thereby facilitating further improvement of the water separation efficiency, and also promoting the efficiency of real-time separation of part of the isopropyl alcohol in the drainage. In addition, when the sensor senses that the floating rate of the floating plate 8 is approaching zero, it can trigger the liquid inlet end of the first movable discharger 6 and the liquid inlet end of the second movable discharger 9 to continue to move downward synchronously. Figure 8 As shown, the liquid inlet end is closed. At this time, the second movable discharger 9 no longer takes in liquid, and the temperature in the kettle causes the dehydrating agent to continue to evaporate until it is completely collected by the water separator 3. The first movable discharger 6 no longer takes in liquid, which makes it convenient to re-add isopropanol to the material box 5 for the next batch of esterification preparation. The water separator 3 discharges the remaining water, and all the dehydrating agent can be recovered for use in the next batch of esterification preparation, thereby achieving further improvement in the efficiency of esterification and water separation in the esterification reaction of diisopropyl succinate, and more convenient operation.

[0035] The drain pipe 31 may be provided with a switch valve electrically connected to the upper sensor 10 and the lower sensor 11 to trigger the on-off control of the drain pipe 31 .

[0036] In an embodiment of the present invention, Figure 1 , Figure 2 , Figure 3 , Figure 4 , Figure 5As shown, the first movable discharger 6 includes a vertical fixed flat cylinder 61, and the top end of the fixed flat cylinder 61 is telescopically connected to the movable flat cylinder 62. The first movable discharger 6 is located on the side of the material box 5 close to the esterification kettle 1, and the length direction of the first movable discharger 6 is parallel to the length direction of the side of the material box 5. The fixed flat cylinder 61 and the movable flat cylinder 62 are similar to the existing telescopic cylinder structure design, but are flattened. Even if there is a gap at the connection between the fixed flat cylinder 61 and the movable flat cylinder 62, a small amount of liquid material flows directly into the fixed flat cylinder 61 along the gap, which has little effect on the discharge. The top end of the fixed flat cylinder 61 is fixedly inserted into the material box 5, and the bottom end of the fixed flat cylinder 61 passes through the outside of the material box 5 and is fixedly inserted downward into the esterification kettle 1. The liquid inlet end of the first movable discharger 6 is located at the top side end of the movable flat cylinder 62, as shown in FIG. Figure 4 As shown, it is located at the top right opening of the movable flat cylinder 62 , the bottom opening of the movable flat cylinder 62 is used to communicate with the fixed flat cylinder 61 , and the liquid outlet end of the first movable discharger 6 is located at the bottom end of the fixed flat cylinder 61 .

[0037] In an embodiment of the present invention, Figure 1 , Figure 2 , Figure 3 , Figure 4 , Figure 5 As shown, the bottom end of the fixed flat cylinder 61 is connected to a flat liquid outlet head 63, and a plurality of liquid outlet holes 64 are arranged at intervals along the length direction of the liquid outlet end of the flat liquid outlet head 63 for dispersing and adding isopropyl alcohol into the kettle.

[0038] In an embodiment of the present invention, Figure 1 , Figure 2 , Figure 3 , Figure 4 , Figure 5 As shown, the second movable discharger 9 includes a vertical fixed flat tube 91, the top of the fixed flat tube 91 is telescopically connected to a movable flat tube 92, the fixed flat tube 91 is fixed to the inner side of the water distributor 3, the structural design of the fixed flat tube 91 and the movable flat tube 92 is similar to the fixed flat cylinder 61 and the movable flat cylinder 62, and the liquid inlet end of the second movable discharger 9 is located at the top side end of the movable flat tube 92, as shown in FIG. Figure 5 As shown, the liquid outlet end of the second movable discharger 9 is located at the bottom side end of the fixed flat tube 91, as shown in FIG. Figure 5 As shown, it is located at the bottom left opening of the fixed flat tube 91 and is connected to the return pipe 32 . The bottom opening of the movable flat tube 92 is used to communicate with the fixed flat tube 91 .

[0039] In an embodiment of the present invention, Figure 1 , Figure 2 , Figure 3 , Figure 4 , Figure 5As shown, after the isopropanol is added into the esterification reactor 1 through the feed box 5 and the first movable discharger 6, the movable flat cylinder 62 and the movable flat tube 92 continue to move downward synchronously until the esterification reaction is completed. Figure 8 As shown, the liquid inlet end of the first movable discharger 6 is completely inserted into the fixed flat cylinder 61, and the liquid inlet end of the second movable discharger 9 is completely inserted into the fixed flat tube 91, which is used to close the liquid outlet of the material box 5 and the reflux liquid outlet of the water separator 3, so as to facilitate the re-addition of isopropyl alcohol and the complete collection of the dehydrating agent.

[0040] In an embodiment of the present invention, Figure 1 , Figure 2 , Figure 3 , Figure 4 , Figure 5 As shown, the top of the movable flat cylinder 62 is connected to a connecting rod 12, one end of the connecting rod 12 passes through the outside of the material box 5, the connecting rod 12 extends by bending, and passes downward into the water separator 3, and is connected to the top of the movable flat tube 92, wherein a driving device 200 for driving the agitator in the kettle to rotate is provided at the top of the esterification kettle 1, and specifically, a driving component such as a lifting cylinder 300 may be provided beside the driving device 200 to drive the connecting rod 12 to rise and fall, and optionally, the lifting cylinder 300 may also be provided on the material box 5 and connected to the middle position of the connecting rod 12.

[0041] In an embodiment of the present invention, Figure 1 , Figure 2 , Figure 3 , Figure 4 , Figure 5 As shown, a vertical groove 33 is opened at the inner end of the water divider 3, and the side edge of the floating plate 8 penetrates into the vertical groove 33 to facilitate the limiting of the floating plate 8. The lower sensor 11 is arranged on the inner bottom end of the vertical groove 33, and the inner side of the top end of the second movable discharger 9 is connected to a horizontal platform 13, which penetrates into the vertical groove 33, and the upper sensor 10 is arranged at the bottom end of the horizontal platform 13.

[0042] Among them, the top end of the water divider 3 can also be vertically connected with a telescopic thin rod 14, the fixed end of the telescopic thin rod 14 is fixedly connected to the top end of the water divider 3, and the bottom end of the movable end of the telescopic thin rod 14 is connected to the floating plate 8, which is conducive to the vertical directional up and down movement of the limiting floating plate 8. The side of the top end of the water divider 3 away from the return pipe 32 can also be vertically connected with an inner tube 15, the top of the inner tube 15 is connected to the bottom end of the second vertical pipe section 43, the bottom end of the inner tube 15 passes through the floating plate 8 and is located below the vertical groove 33, which is used to drain liquid to the bottom of the water divider 3, which is conducive to more complete oil-water separation. More preferably, the inner tube 15 can also adopt the existing conventional telescopic sleeve structure design, the horizontal platform 13 can be extended horizontally and connected to the movable end of the inner tube 15, so as to drive the movable end of the inner tube 15 to move up and down synchronously, so as to better facilitate bottom drainage and oil-water separation.

[0043] The present invention also provides a method for esterification of diisopropyl succinate, comprising the following steps:

[0044] A flattened material box 5 is mounted outside the top of the esterification kettle 1. All the isopropanol liquid required for esterification preparation is added into the material box 5 at one time. The remaining maleic anhydride, dehydrating agent and catalyst materials are added into the esterification kettle 1. The liquid inlet end of the first movable discharger 6 is located in the middle of the material box 5, so that part of the isopropanol in the material box 5 is firstly fed into the kettle by the first movable discharger 6 for reaction. During the esterification reaction, the steam at the top of the kettle is condensed by the condenser 2 and refluxed through the water separator 3 for water separation. The condenser 2 is connected to the heating plate 7 at the bottom of the material box 5 through the heat exchange pipe 71, which is used to keep the isopropanol in the material box 5 warm. The plate 8 always floats on the interface between the dehydrating agent and water recovered in the water separator 3. When the floating plate 8 floats up and approaches the upper sensor 10, the drain pipe 31 is triggered to start drainage, until the floating plate 8 floats down and approaches the lower sensor 11, the drain pipe 31 is triggered to stop drainage, thereby realizing automatic drainage. By sensing that the reaction temperature in the esterification kettle 1 rises to a preset amplitude, and by sensing that the floating rate of the floating plate 8 drops to a predetermined amplitude through the upper sensor 10 and the lower sensor 11, the liquid inlet end of the first movable discharger 6 and the liquid inlet end of the second movable discharger 9 are triggered to move downward synchronously, so that isopropyl alcohol is intermittently added in batches, and the drainage frequency is adaptively adjusted.

[0045] More preferably, when the esterification reaction is completed and the upper sensor 10 and the lower sensor 11 sense that the float plate 8 is no longer floating, the liquid inlet end of the first movable discharging device 6 and the liquid inlet end of the second movable discharging device 9 are triggered to continue to move downward synchronously, so that the liquid inlet end of the first movable discharging device 6 and the liquid inlet end of the second movable discharging device 9 are closed, thereby facilitating the re-addition of isopropyl alcohol and the complete collection of the dehydrating agent.

[0046] Those skilled in the art should understand that the discussion of any of the above embodiments is merely illustrative and is not intended to imply that the scope of the present invention is limited to these examples. Under the concept of the present invention, the technical features in the above embodiments or different embodiments may be combined, the steps may be implemented in any order, and there are many other variations of the different aspects of the present invention as described above, which are not provided in detail for the sake of simplicity.

Claims

1. A diisopropyl succinate esterification reaction device, comprising an esterification kettle (1), the top of the esterification kettle (1) is externally connected to a condenser (2), the bottom of the condenser (2) is connected to a water separator (3), characterized in that: A steam pipe (4) is externally connected to the top of the esterification kettle (1), and the steam pipe (4) is connected to the condenser (2); A material box (5) of flat design is arranged outside the top of the esterification kettle (1), and a liquid adding port (51) is connected to the top of the material box (5) for adding isopropyl alcohol into the material box (5). A first movable discharger (6) is arranged in the material box (5), and a liquid inlet end of the first movable discharger (6) is located in the material box (5), and a liquid outlet end of the first movable discharger (6) passes out of the material box (5) and downwardly penetrates into the esterification kettle (1). A heating plate (7) is arranged on the material box (5), and a heat exchange pipe (71) is arranged in the heating plate (7), and the heating plate (7) is connected to the condenser (2) via the heat exchange pipe (71); The bottom end of the water separator (3) is connected to a drain pipe (31), the side end of the water separator (3) is connected to a reflux pipe (32), one end of the reflux pipe (32) is connected to the esterification kettle (1), a floating plate (8) is provided in the water separator (3), the floating plate (8) floats on the interface between the dehydrating agent and water recovered in the water separator (3), a second movable discharger (9) is provided in the water separator (3), the liquid inlet end of the second movable discharger (9) penetrates upward through the top end of the floating plate (8) and is connected to an upper sensor (10), and the liquid outlet end of the second movable discharger (9) It is fixedly arranged in the water separator (3) and connected to the reflux pipe (32). A lower sensor (11) is correspondingly arranged below the upper sensor (10) in the water separator (3). When the floating plate (8) floats up and approaches the upper sensor (10), the drain pipe (31) is triggered to start draining water, until the floating plate (8) floats down and approaches the lower sensor (11), the drain pipe (31) is triggered to stop draining water. During the esterification reaction, the liquid inlet end of the first movable discharger (6) and the liquid inlet end of the second movable discharger (9) are synchronously and intermittently moved downward, so that isopropyl alcohol is intermittently added in batches, and the upper sensor (10) is driven to move downward synchronously. The first movable discharger (6) comprises a vertical fixed flat cylinder (61), the top end of the fixed flat cylinder (61) is telescopically connected to a movable flat cylinder (62), the top end of the fixed flat cylinder (61) is fixedly inserted into the material box (5), the bottom end of the fixed flat cylinder (61) passes out of the material box (5) and downwardly passes into the esterification kettle (1), the liquid inlet end of the first movable discharger (6) is located at the top side end of the movable flat cylinder (62), and the liquid outlet end of the first movable discharger (6) is located at the bottom end of the fixed flat cylinder (61); The bottom end of the fixed flat cylinder (61) is connected to a flat liquid outlet head (63), and a plurality of liquid outlet holes (64) are arranged at intervals along the length direction of the liquid outlet end of the flat liquid outlet head (63) for dispersing and adding isopropanol into the kettle; The second movable discharger (9) comprises a vertical fixed flat tube (91), the top end of the fixed flat tube (91) is telescopically connected to a movable flat tube (92), the fixed flat tube (91) is fixed to the inner side of the water distributor (3), the liquid inlet end of the second movable discharger (9) is located at the top side end of the movable flat tube (92), and the liquid outlet end of the second movable discharger (9) is located at the bottom side end of the fixed flat tube (91) and is connected to the return pipe (32); After the isopropyl alcohol is added into the esterification kettle (1) via the material box (5) and the first movable discharger (6), until the esterification reaction is completed, the movable flat cylinder (62) and the movable flat tube (92) continue to move downward synchronously, so that the liquid inlet end of the first movable discharger (6) completely penetrates into the fixed flat cylinder (61), and the liquid inlet end of the second movable discharger (9) completely penetrates into the fixed flat tube (91), so as to seal the liquid outlet of the material box (5) and the reflux liquid outlet of the water distributor (3); By sensing that the reaction temperature in the esterification kettle (1) rises to a preset amplitude, and by sensing that the floating speed of the floating plate (8) decreases to a predetermined amplitude through the upper sensor (10) and the lower sensor (11), the liquid inlet end of the first movable discharger (6) and the liquid inlet end of the second movable discharger (9) are triggered to move downward synchronously, so that isopropyl alcohol is intermittently added in batches.

2. A diisopropyl succinate esterification reaction device according to claim 1, characterized in that: The steam pipeline (4) comprises a first vertical pipe section (41) connected to the top of the esterification kettle (1), an inclined pipe section (42) connected to the first vertical pipe section (41), and a second vertical pipe section (43) connected to the inclined pipe section (42); the bottom end of the second vertical pipe section (43) is connected to the top end of the water separator (3); and the condenser (2) is connected to the inclined pipe section (42).

3. A diisopropyl succinate esterification reaction device according to claim 1, characterized in that: The top end of the movable flat cylinder (62) is connected to a connecting rod (12), one end of which passes out of the material box (5) and downwardly penetrates into the water distributor (3) to be connected to the top end of the movable flat tube (92).

4. A diisopropyl succinate esterification reaction device according to claim 1, characterized in that: A vertical groove (33) is provided at the inner end of the water distributor (3), and the side edge of the floating plate (8) penetrates into the vertical groove (33). The lower sensor (11) is arranged on the inner bottom end of the vertical groove (33). A horizontal platform (13) is connected to the inner side of the top end of the second movable discharger (9), and the horizontal platform (13) penetrates into the vertical groove (33). The upper sensor (10) is arranged at the bottom end of the horizontal platform (13).

5. A method for esterification of diisopropyl succinate, wherein the method adopts the diisopropyl succinate esterification reaction device as claimed in any one of claims 1 to 4 to carry out the reaction, characterized in that: The following steps are involved: A material box (5) of flat design is arranged outside the top of the esterification kettle (1), and all the isopropyl alcohol liquid required for esterification preparation is added into the material box (5) at one time. The remaining maleic anhydride, dehydrating agent and catalyst material are added into the esterification kettle (1). The liquid inlet end of the first movable discharger (6) is located in the middle of the material box (5), so that part of the isopropyl alcohol in the material box (5) is firstly added into the kettle through the first movable discharger (6) for reaction. During the esterification reaction, the steam at the top of the kettle is condensed by the condenser (2) and refluxed and separated through the water separator (3). The condenser (2) is connected to the heating plate (7) at the bottom of the material box (5) through a heat exchange pipe (71) to keep the isopropyl alcohol in the material box (5) warm. The water separator (3) The inner floating plate (8) always floats on the interface between the dehydrating agent and water recovered in the water separator (3). When the floating plate (8) floats up and approaches the upper sensor (10), the drain pipe (31) is triggered to start draining, until the floating plate (8) floats down and approaches the lower sensor (11), the drain pipe (31) is triggered to stop draining, thereby realizing automatic drainage. When the reaction temperature in the esterification kettle (1) rises to a preset amplitude and the floating rate of the floating plate (8) drops to a predetermined amplitude through the upper sensor (10) and the lower sensor (11), the liquid inlet end of the first movable discharger (6) and the liquid inlet end of the second movable discharger (9) are triggered to move downward synchronously, so that isopropyl alcohol is intermittently added in batches and the drainage frequency is adaptively adjusted.

6. A method for esterification of diisopropyl succinate according to claim 5, characterized in that: When the esterification reaction is completed and the upper sensor (10) and the lower sensor (11) sense that the floating plate (8) is no longer floating, the liquid inlet end of the first movable discharger (6) and the liquid inlet end of the second movable discharger (9) are triggered to continue to move downward synchronously, so that the liquid inlet end of the first movable discharger (6) and the liquid inlet end of the second movable discharger (9) are closed.

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