High-purity pivalic acid continuous synthesis process based on ratio optimization and temperature and pressure regulation

Abstract

The invention relates to the technical field of synthesis of pivalic acid, and discloses a high-purity pivalic acid continuous synthesis process based on ratio optimization and temperature and pressure regulation. The method comprises the following steps: firstly, acquiring synthetic raw materials, pretreating in a molar ratio range, conveying into a reaction container, and setting reaction parameters to obtain an initial reaction solution; secondly, configuring a parameter optimizer, optimizing reaction parameters to obtain optimal reaction parameters, and feeding back the optimal reaction parameters to the parameter optimizer for reaction to obtain a synthetic reaction solution; transferring the synthetic reaction liquid into a hydrolysis kettle, hydrolyzing, standing, layering to obtain an upper-layer product, a middle-layer product and a lower-layer product, and separating to obtain a pivalic acid crude product; and finally, washing and layering the crude pivalic acid product to obtain a to-be-rectified material, and putting the to-be-rectified material into a rectification device for rectification and purification to obtain high-purity pivalic acid. According to the method, the purpose of continuously synthesizing the high-purity pivalic acid is achieved by optimizing the proportion and regulating and controlling the temperature and the pressure.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of pivalic acid synthesis, in particular to a high-purity pivalic acid continuous synthesis process based on optimized proportioning and temperature-pressure regulation. BACKGROUND

[0002] Pivalic acid (2,2-dimethylpropanoic acid) is an important fine chemical intermediate with wide applications in the synthesis of resins, medicines, pesticides, fragrances, and initiators, etc. due to its unique steric hindrance effect. In particular, high-purity pivalic acid is a key raw material for producing high-efficiency catalysts, high-end medicines, and heat-resistant polymer monomers, and the market demand is growing. Currently, the mainstream method for industrial production of pivalic acid is the synthesis path based on the Koch reaction, i.e. the carbonylation reaction of isobutylene, carbon monoxide, and water under the action of a strong acid catalyst. However, the existing technology, especially the process aiming to realize continuous production, still faces significant challenges in how to accurately control the reaction process to obtain high-purity, low-impurity products. Achieving stable and efficient continuous production of high-purity pivalic acid has become the key to improving the technical level of the industry and reducing production costs.

[0003] The existing continuous synthesis process of pivalic acid is usually based on the improved Koch method, and the process is as follows: after mixing the raw material isobutylene with excess carbon monoxide gas, it is continuously fed into a reactor containing a strong acid catalyst such as concentrated sulfuric acid, boron trifluoride, or their composite, and the carbonylation reaction is carried out under high temperature and high pressure conditions. The reaction product then enters a separation system, the catalyst is separated out, and the pivalic acid product is purified.

[0004] The traditional continuous synthesis process of pivalic acid often uses excess catalyst or reactants to pursue high conversion rate, which not only increases the material circulation load and energy consumption, but also easily generates various by-products, making the subsequent separation and purification complex, greatly affecting the final product yield. At the same time, the lack of control accuracy of reactant proportioning and temperature and pressure causes the reaction process to be unstable, and the quality difference between batches of products is large. SUMMARY

[0005] In view of the problems in the related art, the present application provides a high-purity pivalic acid continuous synthesis process based on optimized proportioning and temperature-pressure regulation to overcome the technical problems existing in the prior art.

[0006] To solve the technical problems, the present application is realized by the following technical scheme: The present application is a high-purity pivalic acid continuous synthesis process based on optimized proportioning and temperature-pressure regulation, comprising the following steps: S1, feed control: obtain synthesis raw materials and pretreat in the molar ratio range to obtain pretreated raw materials, set the feeding mode, deliver the pretreated raw materials to the reaction vessel and set the reaction parameters to obtain the initial reaction liquid; S2, parameter optimization: configure a parameter optimizer, embed an adaptive multi-strategy particle swarm algorithm in the parameter optimizer, take the maximum pinacolic acid yield of the initial reaction liquid as the optimization target, optimize the reaction parameters, obtain the best reaction parameters, and feedback to the parameter optimizer for reaction to obtain the synthesis reaction liquid; S3, hydrolysis and separation: move the synthesis reaction liquid to a hydrolysis kettle and hydrolyze, separate the upper layer product, middle layer product and lower layer product after standing, and then separate to obtain crude pinacolic acid; S4, rectification and purification: obtain the material to be rectified after water washing and layering treatment of the crude pinacolic acid, configure a rectification device, and input the material to be rectified into the rectification device for rectification and purification to obtain high-purity pinacolic acid.

[0007] Preferably, the obtaining of synthesis raw materials and the pretreatment in the molar ratio range comprises the following steps: Obtain synthesis raw materials, keep the molar ratio of the synthesis raw materials controlled as isobutylene:carbon monoxide:industrial sulfuric acid = 1:(1.05-1.15):(3.4-3.8), and pretreat the synthesis raw materials to obtain pressurized liquid isobutylene and purified carbon monoxide gas.

[0008] Preferably, the delivery of the pretreated raw materials to the reaction vessel and the setting of the reaction parameters comprises the following steps: Configure a reaction vessel, use a metering pump to deliver industrial sulfuric acid and pressurized liquid isobutylene to the upper feed port of the reaction vessel, and then deliver the purified carbon monoxide gas into the bottom gas distributor of the reaction vessel; Set the reaction parameters, which include the reaction vessel pressure, the reaction vessel temperature, the stirring speed and the reaction vessel residence time, and the reaction occurs sufficiently in the reaction vessel to obtain the initial reaction liquid.

[0009] Preferably, the embedding of the adaptive multi-strategy particle swarm algorithm in the parameter optimizer comprises the following steps: Real-time monitor the reaction vessel pressure and feedback the signal to the compressor control system; use a closed-loop control system composed of regulating valves to control the circulating cooling medium of the reaction vessel, measure the reaction vessel temperature, and record the stirring speed in real time; Configure a parameter optimizer, integrate the closed-loop control system composed of the compressor control system and the regulating valves into the parameter optimizer, and transmit the stirring speed and the reaction vessel residence time to the parameter optimizer, and embed the adaptive multi-strategy particle swarm algorithm in the parameter optimizer.

[0010] Preferably, the obtaining the optimal reaction parameters comprises the following steps: Real-time detecting the pivalic acid yield of the initial reaction liquid, establishing a fitness function with the maximum pivalic acid yield of the initial reaction liquid as the optimization target; Randomly generating a particle swarm, assigning each particle in the particle swarm with a set of initial velocity and initial position, each particle in the particle swarm representing a set of reaction parameters, and regarding the process of updating the particle position as the process of optimizing the reaction parameters; Determining the fitness function value of each particle in the particle swarm, introducing an adaptive forgetting mechanism, a centroid traction strategy and a dynamic inertia weight updating strategy to update the particle position, and stopping iteration when the current iteration number reaches the maximum iteration number, at which time the global optimal position, i.e. the optimal reaction parameters, is output.

[0011] Preferably, the obtaining the synthesis reaction liquid comprises the following steps: Feeding the optimal reaction parameters into the parameter optimizer, wherein the optimal reaction parameters include optimal reaction vessel pressure, optimal reaction vessel temperature, optimal stirring speed and optimal reaction vessel residence time, and the parameter optimizer restarts the reaction using the optimal reaction parameters to obtain the synthesis reaction liquid.

[0012] Preferably, the moving the synthesis reaction liquid to the hydrolysis kettle and performing hydrolysis comprises the following steps: Moving the synthesis reaction liquid to the hydrolysis kettle, adding soft water with a temperature lower than 25℃ to the hydrolysis kettle, and using the jacket of the hydrolysis kettle to circulate cooling water to maintain the internal temperature of the hydrolysis kettle rectification device at 15- 25℃ to obtain a post-hydrolysis mixture.

[0013] Preferably, the performing separation treatment to obtain pivalic acid crude product comprises the following steps: Letting the post-hydrolysis mixture stand to obtain upper product, middle product and lower product, and performing separation treatment to obtain the upper product, i.e. pivalic acid crude product.

[0014] Preferably, the pivalic acid crude product is subjected to water washing and layering treatment to obtain a material to be rectified, which comprises the following steps: Transferring the pivalic acid crude product to a washing kettle, adding soft water with a volume of 0.5-1.5 times that of the pivalic acid crude product, stirring at 20-40℃ for 10-30 minutes until the mixture is separated into layers, and separating the lower aqueous phase to obtain the material to be rectified.

[0015] Preferably, the feeding the material to be rectified into a rectification device for rectification and purification comprises the following steps: Configuring a rectification device, adding the material to be rectified into the rectification device, and starting a vacuum system to maintain the absolute pressure of the rectification device within the range of 5-15 kPa; The temperature inside the rectification device is increased to 150-170 DEG C at a rate of 20-40 DEG C per hour, when the rectification device overhead temperature is increased to 90-100 DEG C, the overhead condenser is opened, the reflux ratio (2:1) to (4:1) is maintained, and the front fraction is collected; when the rectification device overhead temperature is in the range of 100-105 DEG C, the reflux ratio (1:1) to (3:1) is adjusted, the temperature inside the rectification device is controlled to be not more than 180 DEG C, at this time, the high-purity tert-pentanoic acid is collected at the top outlet of the rectification device; when the rectification device overhead temperature exceeds 105 DEG C, the reflux ratio (4:1) to (8:1) is adjusted, and the rear fraction is collected; until the temperature inside the rectification device is increased to above 185 DEG C or the rectification device overhead temperature exceeds 110 DEG C, the rectification purification operation is stopped, and the high-purity tert-pentanoic acid is obtained.

[0016] The present application has the following beneficial effects: 1. The present application realizes the full and efficient use of the reaction material by obtaining the synthesis raw material and pre-treating in the molar ratio range, using the accurately optimized molar feeding ratio, ensures that the isobutene is fully converted, under the precise temperature and pressure control, the reaction rate and selectivity are optimized, avoids the batch difference and operation fluctuation in the reaction, is beneficial to ensure the consistency of product yield, also reduces the possibility of increasing the side reaction or causing safety risk due to parameter out of control.

[0017] 2. The present application significantly improves the global search ability and convergence performance of the algorithm in complex and high-dimensional problems by embedding the self-adaptive multi-strategy particle swarm algorithm in the parameter optimizer, compared with the traditional algorithm, the convergence speed, accuracy and stability are improved, the reaction parameters are automatically adjusted according to the real-time feedback yield data, the pressure, temperature and other parameters in the reaction process are accurately controlled, the time for obtaining the best process condition is greatly shortened, and the global optimal solution is accurately locked, so as to directly and effectively improve the yield of tert-pentanoic acid to the highest level, realize the maximization of economic benefit.

[0018] 3. The present application moves the synthesis reaction liquid to the hydrolysis kettle and carries out hydrolysis, adopts step-by-step discharge and middle-layer process treatment, reduces the generation amount of high-acidity waste liquid, reduces the cost and environmental pressure of subsequent three-waste treatment, realizes the maximization of recovery of the main product tert-pentanoic acid, reduces the loss of the product in the separation process, thereby significantly improves the final total yield, and is suitable for industrialized continuous production.

[0019] 4. The application obtains the material to be rectified by washing and layering the crude pivalic acid, and then inputs the material to the rectification device for rectification and purification. By combining high vacuum rectification with precise segmented control of reflux ratio, the front and rear fractions are cut off, preventing the decomposition, polymerization or coking of pivalic acid that may occur under the condition of approaching or exceeding the normal pressure boiling point and high heat. Thus, the main product fraction with high purity is focused and collected, and finally high-purity pivalic acid is obtained, and a high product yield is ensured.

[0020] Of course, implementing any product of the present application does not necessarily require all the advantages described above to be achieved at the same time. BRIEF DESCRIPTION OF DRAWINGS

[0021] In order to more clearly illustrate the technical solutions of the embodiments of the application, the following will briefly introduce the drawings needed to be used in the description of the embodiments. Obviously, the drawings in the following description are only some embodiments of the application, and for those skilled in the art, other drawings can also be obtained from these drawings without creative labor.

[0022] Figure 1 The present application provides a flowchart of a continuous synthesis process of high-purity pivalic acid based on optimized proportioning and temperature-pressure regulation. DETAILED DESCRIPTION

[0023] The technical solutions in the embodiments of the application will be described clearly and completely in the following with reference to the drawings in the embodiments of the application. Obviously, the described embodiments are only some embodiments of the application, but not all the embodiments. Based on the embodiments in the application, all other embodiments obtained by those skilled in the art without creative labor are within the protection scope of the application. Embodiment 1

[0024] Further, in order to better introduce the technical solutions of the embodiments of the application, as shown in the drawings, Figure 1 the embodiments of the present application provide a continuous synthesis process of high-purity pivalic acid based on optimized proportioning and temperature-pressure regulation, which specifically includes the following contents: S1, feed control: obtaining synthesis raw materials and pretreating them in a molar ratio range to obtain pretreated raw materials, setting a feed mode, conveying the pretreated raw materials to a reaction vessel and setting reaction parameters to obtain an initial reaction liquid; The S1 includes the following steps: S11, obtaining synthesis raw materials, the synthesis raw materials including isobutene, carbon monoxide and industrial sulfuric acid with a concentration of 80%-90%; keeping the molar ratio of the synthesis raw materials controlled as isobutene:carbon monoxide:industrial sulfuric acid = 1: (1.05-1.15):(3.4-3.8); The membrane separation device is configured to mix carbon monoxide and hydrogen to obtain industrial synthesis gas with a carbon monoxide volume content of 45% to 50%, and then the industrial synthesis gas is introduced into the membrane separation device to obtain purified carbon monoxide gas with a purity higher than 98%; the isobutylene is placed in an isobutylene storage tank and inert gas is introduced to maintain the pressure in the isobutylene storage tank at 0.5 to 1.0 MPa to obtain pressurized liquid isobutylene; the pressurized liquid isobutylene and the purified carbon monoxide gas are used as pretreated raw materials; S12, a reaction container is configured, a metering pump is used to deliver industrial sulfuric acid with a concentration of 80% to 90% and pressurized liquid isobutylene to an upper feed port of the reaction container, and a rated feed flow rate is maintained, and then the purified carbon monoxide gas is delivered into a gas distributor at the bottom of the reaction container; reaction parameters are set, the reaction parameters include reaction container pressure, reaction container temperature, stirring speed and reaction container residence time, wherein the reaction container pressure is controlled to be in the range of 5.5 to 6.0 MPa, the reaction container temperature is maintained in the range of 45 to 50°C, the stirring device of the reaction container is started, the stirring speed is controlled to be in the range of 200 to 250 rpm, the pretreated raw materials are controlled to be in the range of 1.5 to 2.0 hours in the reaction container residence time, and the reaction is fully carried out in the reaction container to obtain an initial reaction liquid, and the initial reaction liquid is continuously produced from the bottom outlet of the reaction container; In this embodiment, the synthesis raw materials are obtained and pretreated in a molar ratio range to obtain pretreated raw materials, which are delivered to the reaction container and the reaction parameters are set to obtain the initial reaction liquid; this method uses an accurately optimized molar feed ratio to achieve full and efficient use of the reaction materials, an appropriate excess of carbon monoxide ensures that isobutylene, one of the key reactants, is fully converted, and under precise temperature and pressure control, the reaction rate and selectivity are optimized, avoiding batch-to-batch differences and operational fluctuations in the reaction, which is conducive to ensuring the consistency of product yield and reducing the possibility of increasing side reactions or causing safety risks due to parameter loss of control; specifically, for example, taking 1500 tons of per year of tert-pentanoic acid as a benchmark, the molar ratio of isobutylene:carbon monoxide:sulfuric acid is set to 1:1.1:3.6, wherein the amount of 85% sulfuric acid is 580 L / h, and the amount of isobutylene is 240 L / h; a continuous stirred tank reactor is used, the reactor is equipped with temperature and pressure sensors and an automatic control system to achieve precise temperature and pressure control, through temperature and pressure control, the reaction temperature is controlled at 40±5°C, the total pressure is maintained at 3.0 MPa, and the carbon monoxide partial pressure is about 2.5 MPa; isobutylene and sulfuric acid are first premixed through a static mixer, carbon monoxide is introduced from the bottom of the reactor, and stirring (speed 300 rpm) is used to ensure full dispersion, under the catalysis of sulfuric acid, isobutylene and carbon monoxide undergo Koch reaction to generate tert-pentanoic acid, and an online pH meter and a chromatograph are arranged at the bottom outlet of the reaction container to monitor the reaction conversion rate and by-products; S2. Parameter optimization: Configure a parameter optimizer, which incorporates an adaptive multi-strategy particle swarm optimization algorithm. With the maximum yield of pentanoic acid in the initial reaction solution as the optimization objective, optimize the reaction parameters to obtain the best reaction parameters, and feed them back to the parameter optimizer to carry out the reaction and obtain the synthetic reaction solution. S2 includes the following steps: S21. A pressure sensor is used to monitor the pressure of the reaction vessel in real time and feed the signal back to the compressor control system; a closed-loop control system consisting of regulating valves is used to control the circulating cooling medium of the reaction vessel, and a temperature sensor is used to measure the temperature of the reaction vessel; the stirring device records the stirring speed in real time. A parameter optimizer is configured to integrate the closed-loop control system consisting of the compressor control system and the regulating valve into the parameter optimizer, and the stirring speed and residence time of the reaction vessel are transmitted to the parameter optimizer; the particle swarm algorithm is improved by integrating the adaptive forgetting mechanism, the centroid traction strategy and the dynamic inertia weight update strategy to obtain the adaptive multi-strategy particle swarm algorithm, and the adaptive multi-strategy particle swarm algorithm is built into the parameter optimizer. S22. Real-time monitoring of the pentavolic acid yield of the initial reaction solution; using the maximum pentavolic acid yield of the initial reaction solution as the optimization objective; establishing a fitness function; and using a parameter optimizer to optimize the reaction parameters to obtain the optimal reaction parameters. The specific steps are as follows: S221. Generate a search space based on the range of reaction parameters, randomly generate a particle swarm within the search space, assign each particle in the swarm an initial velocity and initial position, and set the number of particles in the swarm to [value missing]. p The particle swarm dimension is q In a particle swarm, each particle represents a set of reaction parameters, and the process of updating the particle position is regarded as the process of optimizing the reaction parameters. S222. Determine the fitness function value of each particle in the particle swarm, introduce an adaptive forgetting mechanism, set the forgetting interval length, and each particle in the particle swarm searches for the optimal position within the forgetting interval length based on its fitness function value as the learning object for position update. Set the current iteration number to t The maximum number of iterations is , No. t During the nth iteration i The position of each particle is , No. t During the nth iteration i The velocity of each particle is Set inertia weights and update them using a dynamic inertia weight update strategy to obtain new inertia weights. ; S223. Adopting a centroid-traction strategy, the... tIn the next iteration, the fitness function value of each particle in the swarm is determined, and the particles are sorted according to their fitness function values. Elite particles are selected, and the number of elite particles is determined based on the size of the swarm. The average position of all elite particles is calculated to obtain the position of the particle swarm's center of mass. The learning intensities for the individual optimal position and the global optimal position during the particle position update process are respectively... and , and Represents a random number between the interval [0, 1], the th i Individual particles t The individual's historical best position in the next iteration is Update the particle position to obtain the first... t At the +1st iteration, the... i Particle velocity ,in M Indicates the position of the particle swarm's center of mass; According to the t At the +1st iteration, the... i The velocity of the nth particle was calculated. t At the +1st iteration, the... i Particle position ; At this point, the parameter optimizer uses the first... t At the +1st iteration, the... i The reaction parameters corresponding to each particle position are used to run the system until the system reaches a steady state. The yield of tervastatin under steady state is calculated, and the fitness function value of the particle is determined. The particle position is updated again, and the next iteration begins. The iteration continues until the current iteration number reaches the maximum iteration number, at which point the iteration stops and the globally optimal position, i.e. the optimal reaction parameters, is output. S23. The optimal reaction parameters are fed back to the parameter optimizer. The optimal reaction parameters include the optimal reaction vessel pressure, the optimal reaction vessel temperature, the optimal stirring speed, and the optimal reaction vessel residence time. The parameter optimizer uses the optimal reaction parameters to restart the reaction and obtain the synthesis reaction solution. In this embodiment, an adaptive multi-strategy particle swarm optimization algorithm is built into the parameter optimizer. The algorithm aims to optimize the reaction parameters by achieving the maximum pentanoic acid yield of the initial reaction solution. The optimal reaction parameters are then fed back to the parameter optimizer to produce the synthesized reaction solution. This improved algorithm significantly enhances the global search capability and convergence performance in complex and high-dimensional problems. Compared to traditional algorithms, it shows improvements in convergence speed, accuracy, and stability. This method automatically adjusts reaction parameters based on real-time yield data, precisely controlling parameters such as pressure and temperature during the reaction process. This significantly shortens the time required to obtain optimal process conditions and precisely locks... The goal is to determine the global optimal solution, thereby directly and effectively maximizing the yield of pentylene acid and achieving maximum economic benefits. Specifically, for example, a pressure sensor is used to monitor the pressure of the reaction vessel in real time and feed the signal back to the compressor control system. A closed-loop control system consisting of a temperature sensor and regulating valves is used to control the temperature of the reaction vessel by adjusting the flow rate of the circulating cooling medium. The rotational speed of the stirring device is recorded in real time and transmitted to the control system, integrated into a parameter optimizer. This parameter optimizer is deployed on a host industrial computer or a high-performance industrial server, which uses industrial Ethernet protocols (such as Profinet and Modbus) to achieve this. The system establishes bidirectional data communication between the TCP / IP and DCS / PLC control stations. The control station connects to field sensors (pressure transmitters, temperature sensors, online chromatographs) and actuators (compressor frequency converters, cooling water regulating valves, and stirring motor frequency converters) via I / O modules. Initial baseline parameters are: reaction vessel pressure 5.8 MPa, reaction vessel temperature 47°C, stirring speed 220 rpm, and reaction vessel residence time 1.7 hours. The real-time detected initial pentylamino acid yield (65.2%) is used as the baseline. Maximizing this yield is the optimization objective. A fitness function is established, and a parameter optimizer is initiated for optimization. The particle swarm size is set to 30, the particle dimension to 4, and the search space is: reaction vessel pressure (5.5-6.0 MPa), reaction vessel temperature (45-50°C), stirring speed (200-250 rpm), and reaction vessel residence time (1.5-2 hours).Starting at 0 hours, 30 particles (30 different combinations of reaction parameters) are randomly generated, and each particle is assigned a random initial velocity. The parameter optimizer runs the reaction system using the reaction parameters corresponding to the current particle position. After the system reaches a new steady state, the pentyl acid yield is calculated using online chromatography, and this yield value is used as the fitness function value of the current particle. A forgetting interval length is set, and the historical best position is found within the forgetting interval as the learning object. A new inertial weight is calculated, elite particles are selected, and the position of the particle swarm centroid is determined. The particle velocity and position are updated, and the parameter optimizer then runs the system using the new parameter combination, calculates the yield, and starts the next iteration. The iteration process is repeated until the maximum number of iterations (100) is reached, at which point the optimization stops, and the global optimum is output. The optimal reaction parameters, namely a set of parameters that maximize the yield of pivalic acid, were determined. These optimal parameters included an optimal reaction vessel pressure of 5.7 MPa, an optimal reaction vessel temperature of 58 °C, an optimal stirring speed of 230 rpm, and an optimal residence time of 1.8 hours. The parameter optimizer controlled the entire reaction system to operate continuously under these optimal parameters, resulting in a high-yield synthesis reaction solution. The entire optimization process was expected to be completed within 30-48 hours. After optimization was initiated, a significantly better yield than the initial conditions was achieved on the first working day, and the result converged to near the global optimum within approximately two days. Subsequently, the parameter optimizer could switch to monitoring mode, periodically fine-tuning to compensate for long-term disturbances such as the slow decline in catalyst activity. The pivalic acid yield was significantly increased by 72.7%, with an hourly output of 196.1 kg / h and an annual output of 1569 tons. S3. Hydrolysis and separation: The synthesis reaction solution is transferred to a hydrolysis vessel and hydrolyzed. After standing, the upper, middle and lower layers are obtained by separation. Then, crude tervaline is obtained. S3 includes the following steps: S31. Transfer the synthetic reaction solution to a hydrolysis reactor, add soft water at a temperature below 25°C to the hydrolysis reactor, ensuring that the mass ratio of soft water to synthetic reaction solution is (0.5-1.5):1, and use the jacket of the hydrolysis reactor to circulate cooling water to maintain the internal temperature of the hydrolysis reactor distillation device at 15-25°C, to obtain the hydrolyzed mixture. S32. The hydrolyzed mixture is allowed to stand to obtain an upper layer product, a middle layer product, and a lower layer product. The lower layer product is dilute sulfuric acid, which is discharged through the outlet valve at the bottom of the hydrolysis reactor and recovered as a recycled product. The upper layer product is crude pentameric acid, which is further separated by discharging it through the outlet valve at the top of the hydrolysis reactor and collecting the crude pentameric acid. The middle layer product is retained in the hydrolysis reactor, and 1%-5% of its mass of bentonite is added as a separation aid. The stirring device of the hydrolysis reactor is started and stirred at a speed of 50-150 rpm for 20-60 minutes to obtain a mixed slurry. The mixed slurry is subjected to solid-liquid separation through a high-speed filtration device, and the filtered liquid is collected. The liquid is then subjected to hydrolysis separation again, and the solid filter residue separated by hydrolysis is discharged as waste. In this embodiment, the synthesis reaction solution is transferred to a hydrolysis reactor and hydrolyzed. After standing, the upper, middle, and lower layers are obtained and separated to obtain crude penvalerate. This method uses stepwise discharge and middle layer processing, reducing the amount of high-acidity waste liquid generated, lowering the cost and environmental pressure of subsequent waste treatment, maximizing the recovery of the main product penvalerate, and reducing product loss during separation, thereby significantly improving the final total yield and making it suitable for continuous industrial production. Specifically, for example, the synthesis reaction solution (whose main components are penvalerate, sulfuric acid, water, and a small amount of by-products) is continuously transported to the hydrolysis reactor. Soft water at a temperature below 25°C is added to the hydrolysis reactor, with the mass ratio of soft water to the synthesis reaction solution controlled at 1:1. Circulating cooling water is introduced to precisely control the temperature of the hydrolysis process, maintaining the temperature of the mixture in the reactor at 20±5°C. The stirring device of the hydrolysis reactor is started and stirred at 100 rpm for 15 minutes to ensure that the soft water and the reaction solution are fully mixed and homogeneous, completing the hydrolysis process and obtaining the hydrolyzed mixture. After hydrolysis, the mixture was allowed to stand for 60 minutes. Under gravity, the mixture clearly separated into three layers: the upper layer was mainly an organic phase, namely crude pentovalinic acid; the middle layer was an emulsion layer containing small amounts of pentovalinic acid, water, sulfuric acid, and solid impurities; and the lower layer was an aqueous phase, consisting of dilute sulfuric acid with a concentration of approximately 20-30%. The lower layer of dilute sulfuric acid was completely discharged through the outlet valve at the bottom of the hydrolysis reactor as a recovered product, demonstrating the environmental friendliness and economic efficiency of the process. The upper layer of crude pentovalinic acid was discharged and collected through the outlet valve at the top of the hydrolysis reactor. The remaining product after standing in the hydrolysis reactor… In the middle layer emulsion in the reactor, 3% of the middle layer emulsion mass of bentonite is added as a separation aid. The stirring device of the hydrolysis reactor is started and stirred at 100 rpm for 40 minutes to fully mix the bentonite with the middle layer emulsion, obtaining a mixed slurry. The mixed slurry is then passed through a high-speed filtration device for solid-liquid separation. Designed for acidic and viscous materials, it can achieve rapid and continuous filtration and unloading. The clear liquid mixture is collected and returned to the hydrolysis reactor. The retained solid matter is discharged from the filtration device as waste and disposed of safely. S4. Distillation and purification: The crude pentovalic acid is washed with water and subjected to stratification to obtain the material to be distilled. A distillation apparatus is configured, and the material to be distilled is fed into the distillation apparatus for distillation and purification to obtain high-purity pentovalic acid. S4 includes the following steps: S41. Transfer the crude pentovalinic acid to a washing vessel, add 0.5-1.5 times the volume of the crude pentovalinic acid in soft water, stir at 20-40°C for 10-30 minutes until it settles and separates into layers, separate the lower aqueous phase, and obtain the material to be distilled. S42. Configure a distillation apparatus, specifically a distillation kettle, add the material to be distilled into the distillation apparatus, start the vacuum system, and maintain the absolute pressure of the distillation apparatus within the range of 5-15 kPa. The internal temperature of the distillation unit is raised to 150-170℃ at a rate of 20-40℃ per hour. When the temperature at the top of the distillation unit reaches 90-100℃, the top condenser is turned on, and the reflux ratio is maintained at (2:1)-(4:1) to collect the foremilk. When the temperature at the top of the distillation unit is in the range of 100-105℃, the reflux ratio is adjusted to (1:1)-(3:1) to control the internal temperature of the distillation unit to not exceed 180℃. At this time, high-purity pentametic acid is collected at the top outlet of the distillation unit. When the temperature at the top of the distillation unit exceeds 105℃, the reflux ratio is adjusted to (4:1)-(8:1) to collect the hind fraction. The distillation and purification operation is stopped when the internal temperature of the distillation unit rises above 185℃ or the temperature at the top of the distillation unit exceeds 110℃ to obtain high-purity pentametic acid. In this embodiment, crude penvalerate is washed with water and subjected to stratification to obtain the material to be refined. This material is then fed into a distillation unit for purification to obtain high-purity penvalerate. The purification process, combining high-vacuum distillation with precise segmented control of the reflux ratio, clearly separates the fore- and post-distillate fractions, preventing decomposition, polymerization, or coking of penvalerate that may occur when it approaches or exceeds its atmospheric boiling point and is under high heat. This allows for the focusing and collection of the high-purity main product fraction, ultimately yielding high-purity penvalerate and ensuring a high product yield. Specifically, for example, the collected penvalerate... The crude acid product is transferred from the intermediate storage tank to the washing vessel. Soft water of equal volume to the crude pentyl acid product is added to the washing vessel, and the stirring device is started. The mixture is stirred at 150 rpm for 20 minutes to ensure sufficient contact between the water and the crude product, dissolving any remaining water-soluble impurities. After stirring is stopped, the mixture is allowed to stand for 45 minutes. Under gravity, the mixture clearly separates into layers. The lower aqueous phase (containing dissolved impurities and trace amounts of acid) is completely discharged through the outlet valve at the bottom of the washing vessel and sent to the wastewater treatment system. The upper organic phase (material to be refined) is retained. A distillation apparatus (mainly including a distillation vessel, a packed column, and a top condenser) is then configured. (Instructions, etc.) The material to be distilled is added to the distillation vessel. The vacuum system is activated to maintain the absolute pressure of the entire distillation unit at 10 kPa to significantly lower the boiling point of the material and prevent product decomposition or coking due to high temperatures. The material in the distillation vessel is heated to 160°C at a heating rate of 30°C per hour. When the temperature at the top of the column reaches 92-98°C, the top condenser is turned on, maintaining a reflux ratio of 3:1. The fraction collected at this stage is the foremilk (mainly low-boiling-point impurities and trace amounts of water). When the temperature at the top of the column stabilizes in the range of 100-104°C, the reflux ratio is adjusted to 2:1, and the temperature is controlled... The internal temperature of the distillation vessel does not exceed 180℃. The main fraction, which is high-purity pentametic acid, is collected from the top outlet of the distillation unit. When the temperature at the top of the column exceeds 105℃, it indicates that the high-purity product has been distilled off. The reflux ratio is adjusted to 6:1, and the collection of the later fraction (mainly high-boiling-point byproducts and impurities) begins. When the internal temperature of the distillation vessel rises to 185℃ or the temperature at the top of the column exceeds 110℃, heating is immediately stopped, the vacuum system is shut off, and the distillation operation is terminated. The small amount of residue remaining in the distillation vessel is treated as waste liquid. Throughout the process, the pentametic acid recovery rate is 95%, and the purity of pentametic acid is ≥99.8%. Example 2

[0025] Based on Example 1, but differing from Example 1, only the reaction vessel pressure was optimized, while the reaction vessel temperature, stirring speed, and residence time were fixed. Specifically, the search space was determined as follows: reaction vessel pressure (5.5-6.0 MPa), reaction vessel temperature (45-50°C), stirring speed (200-250 rpm), and residence time (1.5-2.0 hours). The initial reaction vessel pressure was set to 5.8 MPa, the reaction vessel temperature to 48°C, the stirring speed to 225 rpm, and the residence time to 1.75 hours. The parameter optimizer was activated for optimization, and the reaction system was run using the reaction parameters corresponding to the current particle position. After the system reached a new steady state, the online chromatograph... The yield of pivalic acid at this moment was analyzed and calculated, and this yield value was used as the fitness function value of the current particle. The iteration process was repeated, and the optimization was stopped when the maximum number of iterations (100) was reached. The optimal reaction vessel pressure of 5.9 MPa was obtained. The parameter optimizer controlled the entire reaction system to switch to the optimal parameters and continue to operate. At this time, the yield of pivalic acid was 68.5%, the hourly output was 183.9 kg / h, and the annual output was 1471 tons. The higher yield directly translates into higher production efficiency and economic benefits. The optimization effect comes from the linear gain brought about by the improvement of a single factor. At the same time, multiple key parameters are optimized. The synergistic effect between them cannot be achieved by single parameter optimization, thus significantly improving the reaction performance and bringing considerable economic benefits. Example 3

[0026] Based on Example 1, but differing from Example 1, only the reaction vessel temperature was optimized, while the reaction vessel pressure, stirring speed, and residence time were fixed. Specifically, the search space was determined as follows: reaction vessel pressure (5.5-6.0 MPa), reaction vessel temperature (45-50°C), stirring speed (200-250 rpm), and residence time (1.5-2.0 hours). The initial reaction vessel temperature was set to 48°C, the reaction vessel pressure was fixed at 5.75 MPa, the stirring speed at 225 rpm, and the residence time at 1.75 hours. The parameter optimizer was activated for optimization, and the reaction system was run using the reaction parameters corresponding to the current particle position. After the system reached a new steady state, the online chromatograph was used for analysis. The yield of pentavonic acid at this moment was calculated and used as the fitness function value of the current particle. The iteration process was repeated, and the optimization was stopped when the maximum number of iterations of 100 was reached. The optimal reaction vessel temperature of 49.5℃ was obtained. The parameter optimizer controlled the entire reaction system to switch to the optimal parameters and run continuously. At this time, the yield of pentavonic acid was 68.0%, the hourly output was 183.4 kg / h, and the annual output was 1469 tons. The optimization effect comes from the linear gain brought about by the improvement of a single factor. Single parameter optimization limits the potential of temperature optimization because other parameters are fixed in a non-optimal state. At the same time, the effectiveness of reaction temperature is heavily dependent on pressure, mixing efficiency (rotation speed) and reaction time (residence time), resulting in the final result being far inferior to multi-parameter optimization. Example 4

[0027] Based on Example 1, but differing from Example 1, only the stirring speed was optimized, while the reaction vessel pressure, temperature, and residence time were fixed. Specifically, the search space was determined as follows: reaction vessel pressure (5.5-6.0 MPa), reaction vessel temperature (45-50°C), stirring speed (200-250 rpm), and residence time (1.5-2.0 hours). The initial stirring speed was set to 200 rpm, the reaction vessel pressure was fixed at 5.75 MPa, the reaction vessel temperature at 47.5°C, and the residence time at 1.75 hours. The parameter optimizer was then activated for optimization, and the reaction system was run using the reaction parameters corresponding to the current particle position until the system reached the optimal parameters. After reaching a new steady state, the yield of pentavonic acid was calculated using online chromatography and used as the fitness function value of the current particle. The iteration process was repeated until the maximum number of iterations (100) was reached, at which point the optimization was stopped, yielding an optimal stirring speed of 235 rpm. The parameter optimizer controlled the entire reaction system to switch to the optimal parameters and continue operating. At this point, the yield of pentavonic acid was 67.8%, the hourly output was 182.9 kg / h, and the annual output was 1460 tons. The optimization effect came from the linear gain brought about by the improvement of a single factor. Although the single-parameter optimization found the optimal stirring speed of 235 rpm, the gas-liquid mass transfer and reaction kinetics were still not optimal due to the lack of coordinated optimization of pressure and temperature, which limited the yield improvement. Example 5

[0028] Based on Example 1, but differing from Example 1, only the residence time in the reaction vessel was optimized, while the reaction vessel pressure, temperature, and stirring speed were fixed. Specifically, the search space was determined as follows: reaction vessel pressure (5.5-6.0 MPa), reaction vessel temperature (45-50°C), stirring speed (200-250 rpm), and reaction vessel residence time (1.5-2.0 hours). The initial reaction vessel residence time was set to 2.0 hours, and the reaction vessel pressure, temperature, and stirring speed were fixed at 5.75 MPa, 47.5°C, and 225 rpm. The parameter optimizer was then activated to perform optimization, and the reaction system was run using the reaction parameters corresponding to the current particle position until the system reached a new steady state. Subsequently, the online chromatograph analyzed and calculated the yield of pentavonic acid at this moment, and used this yield value as the fitness function value of the current particle. The iteration process was repeated, and when the maximum number of iterations of 100 was reached, the optimization was stopped, and the optimal residence time of the reaction vessel was obtained as 1.8 hours. The parameter optimizer controlled the entire reaction system to switch to the optimal parameters and run continuously. At this time, the yield of pentavonic acid was 68.2%, the hourly output was 183.9 kg / h, and the annual output was 1468 tons. The optimization effect came from the linear gain brought about by the improvement of a single factor. Although the single parameter optimization found the optimal residence time of 1.9 h, the reaction temperature and pressure were not optimal, and the reaction rate itself was limited, requiring a longer compensation time, but still could not achieve the synergistic optimization effect. Example 6

[0029] Based on Example 1, but unlike Example 1, the molar ratio of the synthetic raw materials was not maintained within the range of isobutylene:carbon monoxide:industrial sulfuric acid = 1:(1.05-1.15):(3.4-3.8). Specifically, the synthetic raw materials were obtained, and the molar ratio of the synthetic raw materials was maintained at isobutylene:carbon monoxide:industrial sulfuric acid = 1:0.95:3.0. Based on an annual production of 1500 tons of terpentine, the feed rate of 85% sulfuric acid was 483 L / h, and the feed rate of isobutylene was 240 L / h. At this time, the yield of terpentine was measured. Compared to Example 1, the production cost and waste treatment load decreased by 8.2% for tervastatin, the raw material cost for the product increased by 15%, and the waste treatment load increased by 25%. Insufficient carbon monoxide prevented the Koch reaction from proceeding fully, limiting the yield. Insufficient sulfuric acid reduced catalytic efficiency and also resulted in insufficient water in the reaction system, further inhibiting the main reaction and promoting side reactions such as isobutylene polymerization, leading to a significant decrease in yield. At the same time, the energy consumption required for separating and purifying byproducts also increased accordingly, and the amount of waste gas, waste liquid, and waste residue generated increased significantly. Example 7

[0030] Based on Example 1, the difference from Example 1 is that, during the distillation purification process, the fore- and post-distillate fractions were not separated, and the reflux ratio was not controlled or adjusted. Specifically, the vacuum system was started to maintain the absolute pressure of the distillation apparatus within the range of 10 kPa, and the internal temperature of the distillation apparatus was raised to 150-170°C at a rate of 20-40°C per hour, and the temperature at the top of the distillation column was raised to the range of 90-100°C. The top condenser was then turned on, and the reflux ratio was maintained at (2:1)-(4:1). At this time, the purity of terpentine and terpentine were measured. The recovery rate of pentanoic acid and the stability of the process were analyzed. Compared with Example 1, the purity decreased by 4.3% and the recovery rate of pentanoic acid decreased by 7%. It is impossible to effectively separate light and heavy impurities with similar boiling points, and the product can only reach a lower grade. A large amount of qualified pentanoic acid product is collected or discarded along with the impurities at the beginning and end, resulting in a low overall yield. The later stage of the reactor temperature is high, and the high boiling point is constantly heated in the reactor, which can easily lead to coking and equipment blockage, increase the cleaning frequency and safety hazards. Although the process seems to be simplified, it cannot guarantee the long-term, stable and safe operation of the production equipment.

[0031] In the embodiments 1-7 above, regarding the feedback of optimal reaction parameters to the parameter optimizer, the parameter optimizer does not directly send instructions to the actuator; the optimal reaction parameters output by the algorithm are first written into an independent, monitored setpoint storage area of ​​the DCS; the original basic loop control system of the DCS (such as pressure PID control loop, temperature PID control loop) will continue to run, continuously receiving these new optimal reaction parameters, and smoothly adjusting the production process to the target state with its own safe rate and logic; a seamless switching logic and upper and lower limit interlocks are set between the parameter optimizer and the DCS; any setpoint given by the optimizer must be verified by the safety value of the DCS. If it exceeds the process safety range, the setpoint will be automatically intercepted and ignored by the DCS and an alarm will be triggered, thereby ensuring that the optimization process will never endanger production safety; finally, the parameter optimizer restarts the reaction using the optimal reaction parameters to obtain the synthetic reaction liquid.

[0032] In the description of this specification, references to terms such as "an embodiment," "example," "specific example," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0033] The preferred embodiments of the invention disclosed above are merely illustrative of the invention. These preferred embodiments do not exhaustively describe all details, nor do they limit the invention to the specific implementations described. Clearly, many modifications and variations can be made based on the content of this specification. This specification selects and specifically describes these embodiments to better explain the principles and practical applications of the invention, thereby enabling those skilled in the art to better understand and utilize the invention.

Claims

1. A continuous synthesis process for high-purity pentovalinic acid based on optimized formulation and temperature / pressure control, characterized in that, Includes the following steps: S1. Feed control: Obtain the synthetic raw materials and pretreat them within the molar ratio range to obtain pretreated raw materials. Set the feeding method, transport the pretreated raw materials to the reaction vessel, and set the reaction parameters to obtain the initial reaction solution. S2. Parameter optimization: Configure a parameter optimizer, which incorporates an adaptive multi-strategy particle swarm optimization algorithm. With the maximum yield of pentanoic acid in the initial reaction solution as the optimization objective, optimize the reaction parameters to obtain the best reaction parameters, and feed them back to the parameter optimizer to carry out the reaction and obtain the synthetic reaction solution. S3. Hydrolysis and separation: The synthesis reaction solution is transferred to a hydrolysis vessel and hydrolyzed. After standing, the upper, middle and lower layers are obtained by separation. Then, crude tervaline is obtained. S4. Distillation and purification: The crude pentameric acid is washed with water and subjected to stratification to obtain the material to be distilled. A distillation apparatus is configured, and the material to be distilled is fed into the distillation apparatus for distillation and purification to obtain high-purity pentameric acid.

2. The continuous synthesis process of high-purity pentovalinic acid based on optimized ratio and temperature and pressure control according to claim 1, characterized in that, The process of obtaining synthetic raw materials and pretreating them within a molar ratio range includes the following steps: Obtain the synthetic raw materials, and maintain the molar ratio of the synthetic raw materials as isobutylene:carbon monoxide:industrial sulfuric acid = 1:(1.05-1.15):(3.4-3.8); pretreat the synthetic raw materials to obtain pressurized liquid isobutylene and purified carbon monoxide gas.

3. The continuous synthesis process of high-purity pentovalinic acid based on optimized ratio and temperature and pressure control according to claim 2, characterized in that, The process of conveying the pretreated raw material to the reaction vessel and setting the reaction parameters includes the following steps: Configure a reaction vessel, use a metering pump to deliver industrial sulfuric acid and pressurized liquid isobutylene to the upper feed port of the reaction vessel, and then deliver purified carbon monoxide gas into the bottom gas distributor of the reaction vessel. Set reaction parameters, including reaction vessel pressure, reaction vessel temperature, stirring speed, and reaction vessel residence time, and allow the reaction to fully occur in the reaction vessel to obtain an initial reaction solution.

4. The continuous synthesis process of high-purity pentovalinic acid based on optimized ratio and temperature and pressure control according to claim 3, characterized in that, The method of embedding the adaptive multi-strategy particle swarm optimization algorithm in the parameter optimizer includes the following steps: The pressure of the reaction vessel is monitored in real time and the signal is fed back to the compressor control system; a closed-loop control system consisting of regulating valves is used to control the circulating cooling medium of the reaction vessel, measure the temperature of the reaction vessel, and record the stirring speed in real time. The parameter optimizer is configured to integrate the closed-loop control system consisting of the compressor control system and the regulating valve into the parameter optimizer, and to transmit the stirring speed and the residence time of the reaction vessel to the parameter optimizer. An adaptive multi-strategy particle swarm algorithm is built into the parameter optimizer.

5. The continuous synthesis process of high-purity pentovalinic acid based on optimized ratio and temperature and pressure control according to claim 4, characterized in that, Obtaining the optimal reaction parameters includes the following steps: The yield of pentavonic acid in the initial reaction solution is monitored in real time, and a fitness function is established with the maximum yield of pentavonic acid in the initial reaction solution as the optimization objective. A swarm of particles is randomly generated, and each particle in the swarm is assigned an initial velocity and an initial position. Each particle in the swarm represents a set of reaction parameters, and the process of updating the particle position is regarded as the process of optimizing the reaction parameters. The fitness function value of each particle in the particle swarm is determined, and an adaptive forgetting mechanism, a centroid traction strategy, and a dynamic inertia weight update strategy are introduced to update the particle position until the current iteration number reaches the maximum iteration number, at which point the iteration stops and the global optimal position, i.e. the optimal reaction parameters, is output.

6. The continuous synthesis process of high-purity pentovalinic acid based on optimized ratio and temperature and pressure control according to claim 5, characterized in that, The process of obtaining the synthetic reaction solution includes the following steps: The optimal reaction parameters are fed back to the parameter optimizer. The optimal reaction parameters include the optimal reaction vessel pressure, optimal reaction vessel temperature, optimal stirring speed, and optimal reaction vessel residence time. The parameter optimizer uses the optimal reaction parameters to restart the reaction and obtain the synthesis reaction solution.

7. The continuous synthesis process of high-purity pentovalinic acid based on optimized ratio and temperature and pressure control according to claim 6, characterized in that, The step of transferring the synthesis reaction solution to a hydrolysis vessel and performing hydrolysis includes the following steps: The synthesis reaction solution is transferred to a hydrolysis reactor, soft water at a temperature below 25°C is added to the hydrolysis reactor, and circulating cooling water is introduced through the jacket of the hydrolysis reactor to maintain the internal temperature of the hydrolysis reactor at 15-25°C, thus obtaining the hydrolyzed mixture.

8. The continuous synthesis process of high-purity pentovalinic acid based on optimized ratio and temperature and pressure control according to claim 7, characterized in that, The subsequent separation process to obtain crude pentovalinic acid includes the following steps: The hydrolyzed mixture was allowed to stand to obtain the upper, middle and lower products. The upper product, namely crude tervaline, was then separated to obtain the upper product.

9. The continuous synthesis process of high-purity pentovalinic acid based on optimized ratio and temperature and pressure control according to claim 8, characterized in that, The crude tervaline, after being washed with water and subjected to stratification, yields the material to be distilled through the following steps: The crude pentovalinic acid is transferred to a washing vessel, and soft water with a volume of 0.5-1.5 times that of the crude pentovalinic acid is added. The mixture is stirred at 20-40°C for 10-30 minutes until it settles and separates into layers. The lower aqueous phase is then separated to obtain the material to be distilled.

10. The continuous synthesis process of high-purity pentovalinic acid based on optimized ratio and temperature and pressure control according to claim 9, characterized in that, The step of feeding the material to be distilled into the distillation apparatus for distillation purification includes the following steps: Configure a distillation apparatus, add the material to be distilled into the distillation apparatus, start the vacuum system, and maintain the absolute pressure of the distillation apparatus within the range of 5-15 kPa; The internal temperature of the distillation unit is raised to 150-170℃ at a rate of 20-40℃ per hour. When the temperature at the top of the distillation unit reaches 90-100℃, the top condenser is turned on, and the reflux ratio is maintained at (2:1)-(4:1) to collect the foremilk. When the temperature at the top of the distillation unit is in the range of 100-105℃, the reflux ratio is adjusted to (1:1)-(3:1) to control the internal temperature of the distillation unit to not exceed 180℃. At this time, high-purity pentametic acid is collected at the top outlet of the distillation unit. When the temperature at the top of the distillation unit exceeds 105℃, the reflux ratio is adjusted to (4:1)-(8:1) to collect the hind fraction. The distillation purification operation is stopped when the internal temperature of the distillation unit rises above 185℃ or the temperature at the top of the distillation unit exceeds 110℃ to obtain high-purity pentametic acid.

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