An apparatus for synthesizing hydroxypivalyl piperidine

Abstract

The utility model provides a kind of hydroxyl pivalic acid neopentyl glycol monoester synthesis device, wherein the synthesis device includes: disproportionation reactor, refining system;The inside of the disproportionation reactor is connected by conveying pipeline from bottom to top and is provided with one section of mixed reaction zone and two section reaction zones;The one section of mixed reaction zone is provided with micro-interface unit, and the micro-interface unit is connected with the mixed feed inlet being arranged in the side wall of the disproportionation reactor;The two section reaction zones are provided with flat plug flow reaction component, and the top of the two section reaction zones is provided with discharge port, and the discharge port is connected with the refining system;The refining system includes scraper evaporator, condenser, rectifying column connected in sequence.The conversion rate and selectivity of HPN are significantly improved by integrating micro-interface reinforcement and flat plug flow reaction technology, effectively inhibiting side reactions and reducing energy consumption.

Description

Technical Field

[0001] This utility model relates to the field of preparation of neopentyl glycol monoester of hydroxypentyl pivalate. Specifically, this application pertains to an apparatus and method for synthesizing neopentyl glycol monoester of hydroxypentyl pivalate. Background Technology

[0002] Neopentyl hydroxypentanoate (HPN), chemically named 2,2-dimethyl-3-hydroxypropionic acid-2,2-dimethyl-3-hydroxypropyl ester, is a versatile novel diol with significant applications in polyester, lubricant, and high-grade furniture paint production. Its unique molecular structure, including a long carbon chain, high molecular weight, multiple methyl branches, and side methyl groups, endows polymers synthesized from it with excellent thermal stability, hydrolysis resistance, oxidation resistance, and molecular skeleton flexibility. However, current HPN synthesis methods have significant limitations, mainly consisting of two steps: the first step involves formaldehyde and isobutyraldehyde reacting under an alkaline catalyst to generate the intermediate 2,2-dimethyl-3-hydroxypropanal (HPA), a relatively mature step; the second step involves HPPA undergoing a disproportionation reaction under a catalyst to generate HPN, but this step is time-consuming and involves batch reactions, lacking a continuous process flow, resulting in low product purity and severely restricting the large-scale production of HPN.

[0003] In the existing process, the purified HPA aqueous solution reacts with the catalyst in a batch stirred tank for 1.5 to 2 hours, followed by distillation to obtain HPN. This process suffers from low reaction efficiency and the inability to achieve continuous production. Furthermore, during the HPN purification process, high-boiling-point impurities and inorganic salts in the reboiler easily clog the equipment and discharge pipes, further impacting production efficiency and product quality.

[0004] In view of the above, this application is hereby submitted. Utility Model Content

[0005] The primary objective of this application is to provide a synthesis apparatus for neopentyl glycol monoester of hydroxypentanoic acid. This apparatus achieves efficient dispersion and mass transfer of reactants by integrating micro-interface enhancement and plug flow reaction technology, and precisely controls the temperature and pressure of the reaction process, thereby significantly improving the conversion rate and selectivity of HPN, effectively suppressing side reactions, and reducing energy consumption.

[0006] The second objective of this application is to provide a method for synthesizing neopentyl glycol monoester of hydroxypentanoic acid using an apparatus that is simple to operate and operates under mild conditions.

[0007] To achieve the above objectives, this application provides the following technical solution: An apparatus for synthesizing neopentyl glycol monoester of hydroxypentanoic acid, comprising: a disproportionation reactor and a purification system; The disproportionation reactor is configured from bottom to top with a first-stage mixing reaction zone and a second-stage reaction zone connected by a conveying pipe. The first-stage mixing reaction zone is equipped with a micro-interface unit, which is connected to a mixing inlet located on the side wall of the disproportionation reactor. The second-stage reaction zone is equipped with a plug flow reaction assembly, and a discharge port is located at the top of the second-stage reaction zone, which is connected to the purification system. The purification system includes a scraped evaporator, a condenser, and a distillation column connected in sequence.

[0008] Furthermore, an external circulation pipeline is provided outside the mixing reaction zone, the external circulation pipeline including a micro-interface circulation pump and a high-low temperature circulation machine; the inlet of the micro-interface circulation pump is connected to the outlet of the mixing reaction zone; the high-low temperature circulation machine is located between the outlet of the micro-interface circulation pump and the mixing reaction zone, and the outlet of the high-low temperature circulation machine is connected to the conveying pipeline.

[0009] Furthermore, the plug flow reaction assembly includes a multi-layered baffle structure with adjustable angles, the baffles being arranged in a staggered manner; the baffles can be arranged in any of the following ways to guide the material: horizontal arrangement, vertical arrangement, or a combination of horizontal and vertical arrangement.

[0010] Furthermore, the area of ​​each of the baffles accounts for 5 / 8 to 4 / 5 of the radial or axial cross-sectional area of ​​the two-stage reaction zone, and the spacing between adjacent baffles is 0.1 to 0.3 times the diameter of the two-stage reaction zone.

[0011] Furthermore, it also includes a reagent addition unit, the outlet of which is connected to the feed inlet of the scraped evaporator or the discharge pipe between the discharge outlet at the top of the second-stage reaction zone and the feed inlet of the scraped evaporator.

[0012] Furthermore, the distillation column is provided with a top outlet for discharging light components, a side outlet for discharging neopentyl glycol monoester of hydroxypentyl acid on the side wall, and a bottom outlet for discharging heavy components at the bottom.

[0013] Furthermore, the bottom of the distillation column is also provided with a bottom outlet, which is connected to the feed inlet of the scraped evaporator or the discharge pipe through a second external circulation pipeline to realize the recovery of products in the heavy components.

[0014] Furthermore, it also includes a premixing tank, the side wall of which is provided with a raw material inlet and a catalyst inlet, and the other side wall of which is provided with a mixing outlet, which is connected to the mixing inlet of the disproportionation reactor via a feed pump.

[0015] Compared with the prior art, the beneficial effects achieved by this application are as follows: This application innovatively integrates micro-interface enhancement and plug flow reaction technology, achieving a disruptive breakthrough in the synthesis process of neopentyl glycol monoester of hydroxypentanoic acid. The device employs a three-stage synergistic design consisting of a premixing tank, a micro-interface unit, and a plug flow reaction assembly. The combination of a first-stage micro-interface enhancement and a second-stage plug flow reaction continuously enhances the mass transfer and mixing efficiency in the early stages of the reaction, ensuring full contact between the raw materials and the catalyst, instantly initiating and accelerating the disproportionation reaction, thereby significantly increasing the reaction rate under mild conditions. Subsequently, the material enters the upper plug flow reaction assembly, where staggered multi-layered baffles effectively suppress backmixing, ensuring all materials have nearly uniform residence times. This allows the reaction to proceed smoothly and thoroughly towards completion, minimizing the formation of byproducts. This seamless integration perfectly combines the two core steps of "enhancing the initial reaction" and "ensuring complete reaction," successfully reducing the reaction time from 1.5–2 hours in traditional processes to 45–60 minutes, while achieving high performance indicators of HPA conversion and HPN selectivity of no less than 98%. Further, in the refining process, an innovative fluidizing agent was introduced to form a dynamic lubricating film, enabling the scraped evaporator to operate stably under high-temperature conditions and successfully overcoming the problem of frequent clogging in existing technologies. This solved the problem of HPN not being able to be produced continuously and on a large scale, and shortened the reaction time. The conversion rate of HPN was also significantly improved under mild conditions. Attached Figure Description

[0016] Various other advantages and benefits will become apparent to those skilled in the art upon reading the following detailed description of preferred embodiments. The accompanying drawings are for illustrative purposes only and are not intended to limit the scope of the invention. Furthermore, the same reference numerals denote the same parts throughout the drawings. In the drawings: Figure 1 This is a schematic diagram of the structure of a synthesis apparatus for neopentyl glycol monoester of hydroxypentanoic acid according to the present invention; Figure 2 This is a schematic diagram of the baffle arrangement in the two-stage reaction zone of this utility model.

[0017] Figure reference numerals: 1. HPA feed line, 2. Catalyst feed line, 3. Premix tank, 4. Feed pump, 5. Disproportionation reactor, 6. First stage mixing reaction zone, 7. Second stage reaction zone, 8. Scraped evaporator, 9. Condenser, 10. Distillation column, 11. Transfer line, 12. Micro-interface unit, 13. Micro-interface circulation pump, 14. High and low temperature circulator, 15. Baffle plate, 16. Reagent addition unit, 17. Discharge line, 18. Top outlet, 19. Side outlet, 20. Bottom outlet, 21. Second external circulation line, 22. Bottom outlet. Detailed Implementation

[0018] The technical solution of this utility model will be clearly and completely described below with reference to the accompanying drawings and specific embodiments. However, those skilled in the art will understand that the embodiments described below are only some embodiments of this utility model, not all embodiments, and are only used to illustrate this utility model, and should not be regarded as limiting the scope of this utility model. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of this utility model. Where specific conditions are not specified in the embodiments, conventional conditions or conditions recommended by the manufacturer shall be followed. Where the manufacturers of reagents or instruments are not specified, they are all conventional products that can be purchased commercially.

[0019] In the description of this utility model, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the accompanying drawings and are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this utility model. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0020] In the description of this utility model, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "joining" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model based on the specific circumstances.

[0021] To more clearly illustrate the technical solution of this utility model, the following detailed description is provided in conjunction with the accompanying drawings and specific embodiments. This description is for explanation purposes only and not for limitation.

[0022] This embodiment provides an apparatus for synthesizing neopentyl glycol monoester of hydroxypentanoic acid, the schematic diagram of which is shown below. Figure 1 As shown. Through ingenious engineering design, this device effectively solves the technical problems of low reaction efficiency, difficulty in continuous production, and easy clogging of equipment during product refining in traditional production processes.

[0023] Traditional preparation processes typically involve reacting formaldehyde and isobutyraldehyde to generate an aqueous HPA solution. This reaction solution requires steps such as isobutyraldehyde and catalyst recovery and purification to obtain refined HPA. Subsequently, the refined HPA undergoes a disproportionation reaction with the catalyst in a batch stirred reactor, a process that usually takes 1.5 to 2 hours. After the reaction is complete, the final HPN product is obtained through distillation. This traditional technical approach has several significant drawbacks: the disproportionation reaction time is long, the entire reaction process remains in a batch operation mode, resulting in low reaction efficiency and the inability to achieve continuous production.

[0024] The synthesis apparatus of this invention specifically includes: a premixing tank 3, a disproportionation reactor 5, a scraped evaporator 8, a condenser 9, and a distillation column 10. In the reaction section, the apparatus first includes a premixing tank 3. One side of the premixing tank 3 is connected to an HPA feed pipe 1 and a catalyst feed pipe 2, used to initially mix the raw material HPA and the catalyst at 60-100℃. This design aims to accommodate the feeding and dispersion requirements of catalysts in different physical states, ensuring sufficient wetting and dispersion of solid catalysts, or achieving uniform miscibility of liquid catalysts, creating conditions for subsequent efficient reactions. It effectively prevents the agglomeration and sedimentation of solid catalysts and avoids the stratification or uneven distribution of liquid catalysts, thereby ensuring the stability of the feed concentration of various catalysts and guaranteeing reliable continuous production from the source. The catalyst of this invention can be one or more of magnesium hydroxide, magnesium oxide, silica / magnesium oxide, acetylacetonate, benzoylpyruvate, and tetrabutyl titanate.

[0025] The premixed material is then pumped by the feed pump 4 to a first-stage mixing reaction zone 6 of the disproportionation reactor 5. This first-stage mixing reaction zone 6 is equipped with a micro-interface unit 12. The main purpose of the micro-interface unit 12 is to deeply enhance the premixed material through its unique high-speed shearing and mixing capabilities. Through mechanical action, the catalyst and liquid raw materials are further dispersed, forming a more uniform and stable mixing system, thereby significantly increasing the reaction contact area and enhancing the mass transfer process. In this first-stage mixing reaction zone 6, the reaction temperature is controlled at 70-100℃, and the pressure is maintained at 0.1-0.5 MPaG. This enhanced dispersion effect greatly promotes the contact efficiency between reactants, thus increasing the reaction rate. Simultaneously, an external circulation pipeline is provided outside this first-stage mixing reaction zone 6. A portion of the reaction liquid is drawn out by the micro-interface circulation pump 13 and returned to the conveying pipeline 11 after precise temperature control by a high-low temperature circulator. Furthermore, the design of the external circulation pipeline not only removes reaction heat in a timely manner to prevent local overheating, but also promotes the continuous dispersion of the catalyst, further enhancing the mixing effect of the system and achieving the uniformity and stability of the reaction system, providing key support for improving reaction selectivity and conversion rate. After the reactants have reacted in the mixing reaction zone 6, a portion of them are then returned to the micro-interface unit 12 via the transfer pipe 11 to further enhance the dispersion, mass transfer, and heat transfer processes in the reaction system. Through this reflux, the catalyst and HPA feedstock pass through the high-shear zone multiple times, effectively preventing catalyst sedimentation or agglomeration and maintaining a highly dispersed state for continuous disproportionation. Simultaneously, this loop acts as a highly efficient internal thermal management system. The micro-interface circulation pump 13 removes the heat of reaction as it draws out the reactants. The reactants then flow through the high-low temperature circulator 14, an external heat exchanger, where they can be precisely cooled or heated to the target temperature before being reinjected into the disproportionation reactor 5. This not only precisely controls the reaction temperature, preventing side reactions caused by localized overheating and improving reaction selectivity, but also significantly enhances the heat transfer efficiency within the system, ensuring the reaction proceeds under optimal and constant temperature conditions.

[0026] The other portion of the reactants enters the second-stage reaction zone 7, which aims to complete the final stage of the reaction and ensure high and stable selectivity of the product. In the second-stage reaction zone 7 for HPA disproportionation to HPN, the arrangement and structural parameters of the baffles 15 must closely match the flow characteristics of the reactants and the reaction requirements. Its most direct and crucial effect is to significantly constrain and guide the flow path of the reactants. Figure 2 The baffle 15 can be arranged horizontally, vertically, or in a combination of both. Each arrangement is suitable for different scenarios: vertical arrangement is more suitable for reaction systems that require enhanced radial mixing, as it can increase the intensity of local turbulence by radially diverting the reactants; horizontal and vertical combination arrangement can flexibly adjust the flow trajectory of the reactants to meet the multi-dimensional mass transfer requirements of complex reaction systems; and horizontal arrangement, with its strong constraint on the vertical flow of reactants, makes it easier to achieve controllable extension of the reaction path, which is especially suitable for continuous reactions such as HPA that require full contact with the catalyst. Meanwhile, the area of ​​the baffle 15 needs to be controlled within 5 / 8 to 4 / 5 of the radial or axial cross-sectional area of ​​the reaction zone. This range avoids insufficient material guiding force due to an excessively small area, which could easily lead to local short-circuit flow, while preventing a surge in flow resistance due to an excessively large area, which could cause material stagnation or excessive pressure drop. The spacing between adjacent baffles 15 is set to 0.1 to 0.3 times the diameter of the reaction zone. This takes into account the turbulence intensity and residence time when the material turns. If the spacing is too small, the material will turn too frequently, increasing energy consumption and flow resistance. If the spacing is too large, the reaction path cannot be effectively extended, making it difficult to ensure sufficient contact. This range of parameters provides space for HPA disproportionation reactions of different reaction scales and different material viscosities, ensuring that reaction efficiency and device stability are considered on the basis of continuous operation.

[0027] Specifically, in this embodiment, horizontally arranged baffles 15 are selected, with their area occupying 4 / 5 of the radial direction of the two-stage reaction zone 7. From the perspective of reaction requirements, the HPA disproportionation reaction needs to avoid the local stagnation problem of traditional batch reactors, and at the same time, it is necessary to extend the contact time between HPA raw materials and catalysts to improve conversion rate. The horizontally arranged baffles 15 can forcibly guide the vertically flowing reactants, forcing them to turn along the surface of the baffles 15 to form a "Z-shaped" continuous flow trajectory, completely eliminating dead zones and laying the foundation for continuous production. The area is set to 4 / 5 of the radial direction because this parameter can achieve an optimal balance between guidance and flowability. The 1 / 5 reserved flow gap can ensure smooth flow of reactants, avoid excessive pressure drop, and increase the flow velocity of reactants at the gap through the cross-sectional contraction effect, forming local turbulence, breaking the diffusion boundary layer between reactants and catalysts, accelerating the mass transfer process, and further improving the conversion rate of HPA. At the same time, the spacing parameter between adjacent baffles 15 is 0.2 times the diameter of the reaction zone, which is an optimized value after trade-offs. If the spacing is too small, although it can further shorten the material turning cycle, it will result in the space between adjacent baffles 15 being too narrow, and the flow resistance of the reactants will increase sharply. Not only will it require additional pressure to maintain the flow, but it may also cause short-circuit flow due to excessively high local flow velocity. Some reactants will pass through quickly without fully reacting, which will reduce the reaction conversion rate. If the spacing is too large, the space between adjacent baffles 15 will be too large. The reactants will have a long straight flow section before turning, which will easily form a laminar flow state, reduce the mass transfer efficiency, and make it impossible to make full use of the space in the second-stage reaction zone 7 to extend the contact time, which will make it difficult to meet the reaction time requirements of the HPA disproportionation reaction. The 0.2x spacing design perfectly balances flow resistance and mass transfer efficiency: on the one hand, this spacing provides sufficient turning space for the reactants, avoiding increased energy consumption due to excessive resistance, while ensuring a stable transition flow between adjacent baffles 15. During turning, the change in flow velocity generates moderate turbulence, promoting uniform mixing of HPA and catalyst. On the other hand, the 0.2x spacing allows for the reasonable setting of the number of baffles 15 within the limited height of the two-stage reaction zone 7. It avoids the baffles being too dense due to too small a spacing, or the baffles being too numerous due to too large a spacing, thus preventing the reaction path from being insufficiently extended. This ensures that in continuous feeding mode, the reactants can obtain sufficient reaction time through multiple turnings, laying the foundation for improving HPA conversion rate.

[0028] When the above-mentioned technical features are combined, they form a synergistic effect, producing a synergistic effect of 1+1>2, and completely solving the problems of traditional HPA disproportionation reaction processes. In terms of material flow and reaction path optimization, the horizontally arranged large-area baffles 15 force the material to form a Z-shaped baffle trajectory, while the spacing of 0.2 times the diameter precisely controls the step length of each baffle segment. This ensures that the reactants have sufficient time to contact the catalyst in each flow segment, and through reasonable step length design, the overall reaction path is extended to 4 to 6 times that without baffles. Compared with other spacing and area combinations, it can more efficiently utilize the space of the two-stage reaction zone 7, achieving a unity of continuous flow and full reaction, fundamentally breaking through the efficiency bottleneck of traditional batch processes. Secondly, in terms of improving mass transfer and reaction uniformity, the 1 / 5 radial gap and 0.2 times diameter spacing reserved in the large-area baffle plate create a dual turbulence effect: when the material passes through the 1 / 5 gap, the cross-sectional contraction causes a primary velocity increase, forming local turbulence; after entering the 0.2 times diameter spacing region between adjacent baffle plates, the flow changes direction and generates secondary turbulence. The dual turbulence completely breaks the diffusion boundary layer between reactants and catalyst, accelerates molecular mass transfer, and avoids the problem of insufficient or excessive turbulence that may be caused by a single parameter. This allows HPA molecules to bind to the active sites of the catalyst uniformly and quickly, significantly improving the disproportionation reaction conversion rate and reducing residual impurities. Finally, in terms of reactor stability and product purity assurance, the combination of these two factors can effectively suppress the formation of high-boiling-point substances and equipment blockage: the small reaction units divided by horizontal large-area baffles, combined with the orderly flow formed by appropriate spacing, ensure uniform heat transfer and avoid local overheating that could lead to side reactions; at the same time, stable Z-shaped flow and moderate turbulence can continuously flush the inner wall of the reaction zone and the surface of the baffles, preventing inorganic salt crystals from adhering and agglomerating, and further ensuring long-term continuous operation of the equipment, reducing downtime and maintenance caused by blockage, ultimately realizing continuous, efficient and high-purity production of HPN synthesis, providing key technical support for its large-scale application.

[0029] In other words, the integrated micro-interface component 12 and baffle 15 design in this invention creates a flow field characteristic that ensures there are no dead zones or short-circuit channels inside the disproportionation reactor 5, allowing for efficient utilization of the reactor's volume and contributing to continuous production. This maximizes reaction efficiency without increasing the volume of the disproportionation reactor 5, which helps shorten the total residence time to 45-60 minutes.

[0030] In the process of the HPN reaction liquid, after passing through the plug flow reaction assembly, being fed into the scraped evaporator 8 via the purification system from the top outlet of the second-stage reaction zone 7, the discharge pipe 17 between the outlet of the reagent addition unit 16 and the inlet of the scraped evaporator in this embodiment is connected. This design allows the HPN reaction liquid to be mixed with the fluidizing agent before entering the scraped evaporator 8, with the addition amount accounting for 0.5%-5% of the mass of the HPN reaction liquid. This design specifically addresses the long-standing problem of equipment scaling and pipe blockage caused by high-boiling-point impurities, inorganic salts, and catalyst residues during the purification process. In this embodiment, the added fluidizing agent is polyethylene glycol (400-800 g / mol). The addition of the fluidizing agent significantly improves the flowability of high-viscosity materials, reduces the tendency of the HPN reaction liquid to adhere to the heat transfer surface, and provides a guarantee for the stable operation of the subsequent evaporation and separation process. The mixed material enters the scraped evaporator 8 and operates under high temperature conditions of 180-200℃ and high vacuum conditions of 500-600 Pa. The scraped evaporator 8 is equipped with rotating scrapers inside, which continuously renew the heat transfer surface through mechanical scraping. This enhances heat transfer efficiency and prevents coking or fouling of materials on the high-temperature wall surface, allowing HPN and light components to evaporate efficiently and achieve preliminary separation from heavy components, salts, and catalyst residues. The heavy components, salts, and a small amount of catalyst, along with the fluidizing agent, are discharged through pipelines at the bottom of the scraped evaporator 8. The evaporated gaseous components enter the condenser 9 to be condensed into liquid, and then sent to the distillation column 10 for final purification.

[0031] The distillation column 10 operates under a negative pressure of 0.6-12 kPa. High-purity product separation is achieved through precise control of the temperature gradient and gas-liquid balance within the column. Light component impurities are discharged from the top outlet; high-purity HPN product is collected through the side outlet. Specifically, the HPN product prepared by this synthesis device has a purity ≥99.9%. The heavy components in the reboiler are partially discharged as waste from the bottom outlet 20, and the remaining portion is returned from the bottom outlet 22 to the discharge pipe 17 via the second circulation pipeline 21, where it mixes with the HPN reaction liquid and fluidizing agent and re-enters the scraped evaporator 8 for further processing. The purpose of the second circulation pipeline 21 is to recover entrained neopentyl hydroxypentanoic acid monoester, improving the overall utilization rate of raw materials, reducing waste emissions, lowering production costs, and ensuring that the synthesis device meets the requirements of green chemistry and sustainable development.

[0032] In other words, the synthesis apparatus of this invention, through the innovative integration of the micro-interface enhancement unit 12, the plug flow reaction component, and the fluidizing agent-assisted purification system, successfully constructs an efficient, continuous, and stable HPN production path. The HPA disproportionation reaction conversion rate is ≥98%, and the HPN selectivity is ≥98%. The purpose of using this synthesis apparatus is not only to replace the traditional inefficient batch process, but also to improve the conversion rate and product yield of synthesized HPN, solve the engineering problems restricting the large-scale production of HPN, improve reaction efficiency and HPN purity, achieve long-term stable operation of the synthesis apparatus, and significantly reduce energy and material consumption.

[0033] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this utility model, and are not intended to limit it. Although the utility model has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of this utility model.

Claims

1. An apparatus for synthesizing neopentyl glycol monoester of hydroxypentanoic acid, characterized in that, include: Disproportionation reactor, purification system; The disproportionation reactor is configured from bottom to top with a first-stage mixing reaction zone and a second-stage reaction zone connected by a conveying pipe. The first-stage mixing reaction zone is equipped with a micro-interface unit, which is connected to a mixing inlet located on the side wall of the disproportionation reactor. The second-stage reaction zone is equipped with a plug flow reaction assembly, and a discharge port is located at the top of the second-stage reaction zone, which is connected to the purification system. The purification system includes a scraped evaporator, a condenser, and a distillation column connected in sequence.

2. The apparatus for synthesizing neopentyl glycol monoester of hydroxypentanoic acid according to claim 1, characterized in that, An external circulation pipeline is provided outside the mixing reaction zone. The external circulation pipeline includes a micro-interface circulation pump and a high-low temperature circulation machine. The inlet of the micro-interface circulation pump is connected to the outlet of the mixing reaction zone. The high-low temperature circulation machine is located between the outlet of the micro-interface circulation pump and the mixing reaction zone. The outlet of the high-low temperature circulation machine is connected to the conveying pipeline.

3. The apparatus for synthesizing neopentyl glycol monoester of hydroxypentanoic acid according to claim 1, characterized in that, The plug flow reaction assembly includes a multi-layered baffle structure with adjustable angles, the baffles being arranged in a staggered manner; the baffles can be arranged in any of the following ways to guide the material: horizontal, vertical, or a combination of horizontal and vertical.

4. The apparatus for synthesizing neopentyl glycol monoester of hydroxypentanoic acid according to claim 3, characterized in that, The area of ​​each of the baffles accounts for 5 / 8 to 4 / 5 of the radial or axial cross-sectional area of ​​the two-stage reaction zone, and the spacing between adjacent baffles is 0.1 to 0.3 times the diameter of the two-stage reaction zone.

5. The apparatus for synthesizing neopentyl glycol monoester of hydroxypentanoic acid according to claim 1, characterized in that, It also includes a reagent addition unit, the outlet of which is connected to the feed inlet of the scraped evaporator or the discharge pipe between the discharge outlet at the top of the second-stage reaction zone and the feed inlet of the scraped evaporator.

6. The apparatus for synthesizing neopentyl glycol monoester of hydroxypentanoic acid according to claim 5, characterized in that, The distillation column is provided with a top outlet for discharging light components, a side outlet for discharging neopentyl glycol monoester of hydroxypentyl acid on the side wall, and a bottom outlet for discharging heavy components at the bottom.

7. The apparatus for synthesizing neopentyl glycol monoester of hydroxypentanoic acid according to claim 6, characterized in that, The distillation column is also provided with a bottom outlet, which is connected to the feed inlet of the scraped evaporator or the discharge pipe through a second external circulation pipeline to realize the recovery of products in heavy components.

8. The apparatus for synthesizing neopentyl glycol monoester of hydroxypentanoic acid according to any one of claims 1-7, characterized in that, It also includes a premixing tank, which has a raw material inlet and a catalyst inlet on its side wall, and a mixing outlet on its other side wall. The mixing outlet is connected to the mixing inlet of the disproportionation reactor via a feed pump.

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