2,5-furandicarboxylic acid batch production system using furanate as raw material and process flow thereof

Abstract

The present application belongs to the technical field of FDCA production, and particularly relates to a system and process flow for batch production of 2,5-furan dicarboxylic acid with furanate as raw material. The system comprises a loaded particle preparation unit, which is prepared by immersing inert particles in a mother liquor, and then drying to obtain loaded particles loaded with furanate and catalyst; a reaction unit for reaction of the loaded particles with carbon dioxide to convert the furanate into furan dicarboxylic acid; a product separation unit for immersing the reacted loaded particles in a solvent to separate the furan dicarboxylic acid from the inert particles, and recycle the inert particles; a product refining unit for acidifying the solution from the product separation unit to convert the furan dicarboxylic acid into 2,5-furan dicarboxylic acid crude product; and the 2,5-furan dicarboxylic acid crude product is dissolved again, evaporated, crystallized and dried to obtain refined 2,5-furan dicarboxylic acid. The present application has moderate energy consumption, high reaction efficiency, and lower cost of produced 2,5-furan dicarboxylic acid.

Description

Technical Field

[0001] This invention belongs to the field of FDCA production technology, and specifically relates to a system and process for batch production of 2,5-furandicarboxylic acid using furoate as raw material. Background Technology

[0002] 2,5-Furandicarboxylic acid (FDCA) is a derivative of furan. Due to the presence of an aromatic ring in its molecular structure, it can effectively improve the heat resistance and mechanical properties of bio-based polymers. It is considered an ideal substitute for the petroleum-based monomer terephthalic acid (PTA) and can also replace isophthalic acid, adipic acid, succinic acid, bisphenol A, etc. in the synthesis of bio-based polymers such as polyesters, polyamides, and epoxy resins, showing huge market potential.

[0003] It has been reported that FDCA can currently be prepared from various starting materials, including 5-hydroxymethylfurfural (HMF), furoate, hexonic acid, and diethylene glycol. The route using HMF as a starting material is currently the mainstream industrial route, and pilot-scale plants have already been built. However, HMF is mostly derived from the hydrolysis of food raw materials such as glucose, fructose, and galactose, which is not only relatively expensive, but large-scale production also requires consideration of the coordination between food and industrial applications. Using inedible lignocellulose for preparation further increases the price of the raw materials. Furthermore, the reaction requires precious metal catalysts, all of which contribute to the high cost of FDCA produced via this route.

[0004] For routes to prepare FDCA from furoate, the reaction conditions are generally considered harsh, energy consumption is high, and temperature has a significant impact on the conversion rate. Therefore, industrial processes for preparing FDCA from furoate are rarely reported to date. However, the preparation of FDCA from furoate requires the consumption of carbon dioxide (CO2), which also addresses the social issue of carbon sequestration. Since furoate, carbon dioxide, and catalysts are all inexpensive and readily available, FDCA produced via this route can be produced at a lower cost and is more competitive in the market. Summary of the Invention

[0005] To address the aforementioned problems, the present invention aims to provide a system and process for batch production of 2,5-furandicarboxylic acid using furoate as raw material. This system and process have moderate energy consumption, high reaction efficiency, and lower cost of producing 2,5-furandicarboxylic acid.

[0006] To achieve the above objectives, the present invention adopts the following technical solution: An embodiment of the present invention provides a system for batch production of 2,5-furandicarboxylic acid using furoate as a raw material, comprising: The loaded particle preparation unit involves immersing inert particles in a mother liquor made by dissolving furoate and catalyst in a solvent; then drying the immersed particles to obtain loaded particles loaded with furoate and catalyst. The reaction unit is used to fully contact and react the supported particles with carbon dioxide under set temperature and pressure conditions to convert furoate into furan dicarboxylate. The product separation unit is used to immerse the reacted loaded particles in a solvent to separate furan dicarboxylate from the inert particles, allowing the inert particles to be recycled. In the product refining unit, the solution from the product separation unit is acidified to convert furanyl dicarboxylate into crude 2,5-furanyl dicarboxylic acid. The crude 2,5-furanyl dicarboxylic acid is then dissolved again, evaporated and crystallized, and dried to obtain refined 2,5-furanyl dicarboxylic acid.

[0007] The loaded particle preparation unit includes a salt dissolving tank, a fluid conveying device, a loading process vessel, a centrifugal filter, a fluid recovery device, and a drying device. The salt dissolving tank is connected to the loading process vessel via the fluid conveying device. The loading process vessel is connected to the centrifugal filter via a pipeline. The centrifugal filter is connected to the salt dissolving tank via the fluid recovery device. The salt dissolving tank is used to dissolve solid salt and prepare a mother liquor. The fluid conveying device is used to transport the mother liquor to the loading process vessel, which is used to immerse inert particles in the mother liquor to obtain loaded particles. The centrifugal filter is used to separate the loaded particles and the mother liquor. The fluid recovery device is used to transport the mother liquor back to the salt dissolving tank. The drying device is used to dry the loaded particles.

[0008] The loaded particle preparation unit also includes a crusher, which is used to crush the solid salt into fine particles and then inject them into the salt dissolving tank. The salt dissolving tank is equipped with a stirrer to stir the solution and accelerate the dissolution of the solid salt. The fluid conveying equipment includes a conveying pipeline and a mother liquor feed pump and a feed filter installed on the conveying pipeline; the fluid recovery equipment includes a mother liquor recovery tank, a mother liquor recovery pump and a recovery liquid filter, wherein the mother liquor recovery tank is connected to the centrifugal filter through a recovery pipeline and is used to recover the mother liquor separated by the centrifugal filter; the mother liquor recovery tank is connected to the salt dissolving tank through a circulation pipeline, and the mother liquor recovery pump and the recovery liquid filter are sequentially installed on the circulation pipeline.

[0009] The reaction unit includes a fluidized bed reactor, a carbon dioxide heat exchange system, a heat pump system, a condenser, and a gas-liquid separator. The fluidized bed reactor and the gas-liquid separator are connected by a carbon dioxide delivery pipeline and a carbon dioxide recovery pipeline to form a circulating delivery pipeline. The fluidized bed reactor is used to load particles to react with carbon dioxide. The carbon dioxide output from the fluidized bed reactor passes through the carbon dioxide recovery pipeline, the condenser, and then enters the gas-liquid separator. The carbon dioxide heat exchange system and the heat pump system are both connected between the carbon dioxide delivery pipeline and the carbon dioxide recovery pipeline for heat exchange. A carbon dioxide compressor is installed on the carbon dioxide delivery pipeline to compress the delivered carbon dioxide gas.

[0010] The bottom of the fluidized bed reactor is equipped with a gas distributor, which is connected to the carbon dioxide delivery pipeline via a metal hose. An electric heater is installed on the carbon dioxide delivery pipeline, and the electric heater is connected to the reaction temperature control system. The reaction temperature control system detects the reaction temperature inside the fluidized bed reactor through a reaction temperature monitoring sensor. The fluidized bed reactor is equipped with a jacketed temperature control system on the outside, which is used to provide temperature compensation for the fluidized bed reactor. The upper part of the fluidized bed reactor is equipped with a wire mesh filter and a reactor differential pressure monitoring system for detecting the pressure difference between the upper and lower sides of the wire mesh filter. When the wire mesh filter is clogged, the reactor differential pressure monitoring system will sound an alarm. The top of the fluidized bed reactor is equipped with a reactor pressure control system, which is used to control the gas pressure inside the fluidized bed reactor.

[0011] The carbon dioxide recovery pipeline is equipped with a cyclone separator and a bag filter, which are located between the carbon dioxide heat exchange system and the heat pump system. A flow control system is provided between the carbon dioxide delivery pipeline and the carbon dioxide recovery pipeline. When the pressure on the carbon dioxide delivery pipeline exceeds a set value, the flow control system releases carbon dioxide from the carbon dioxide delivery pipeline into the carbon dioxide recovery pipeline.

[0012] The product separation unit includes n sequentially connected separation units. Each unit includes a washing tank, a centrifugal filter, and a solution tank. The bottom of the washing tank is connected to the centrifugal filter via a pipeline, and the top of the washing tank is connected to the solution tank of the next stage via a pipeline equipped with a solution lift pump. The load particles washed in the washing tank enter the centrifugal filter for filtration. The filtered load particles enter the washing tank of the next stage separation unit. The solution filtered by the centrifugal filter enters the solution tank, and the solution in the solution tank is transported to the washing tank of the previous stage via the solution lift pump.

[0013] The product refining unit includes a filtration device, a reverse osmosis system, a fluid conveying device, an acidification tank, a dissolving device, an evaporation crystallization system, and a drying device arranged sequentially along the process flow. The filtration device is used to filter and decolorize the salt solution sent from the product separation unit; the reverse osmosis system is used to concentrate the salt solution; the fluid conveying device is used to send the concentrated refined brine into the acidification tank, which is used to acidify the refined brine. Under acidic conditions, furanyl dicarboxylate is converted into 2,5-furanyl dicarboxylic acid and precipitates due to saturation. After most of the water is removed by the crude product centrifugal filter, it becomes crude 2,5-furanyl dicarboxylic acid. Crude 2,5-furandicarboxylic acid is sequentially dissolved, crystallized, and dried using a dissolving device, an evaporation crystallization system, and a drying device to obtain refined 2,5-furandicarboxylic acid.

[0014] Another embodiment of the present invention provides a process flow for the batch production of 2,5-furandicarboxylic acid using furoate as a raw material, comprising the following steps: A solution is prepared by dissolving furoate and catalyst in a solvent in a predetermined ratio. Inert particles are immersed in a solution to load furoate and catalyst onto the inert particles, thus obtaining loaded particles. The loaded particles are brought into full contact with carbon dioxide under set temperature and pressure conditions to react and convert furoate into furanyl dicarboxylate. The loaded particles after the reaction are immersed in a solvent to separate furan dicarboxylate from the inert particles, and the inert particles are recycled. The solution after separation of inert particles is acidified to convert furanyl dicarboxylate into crude 2,5-furanyl dicarboxylic acid; the crude 2,5-furanyl dicarboxylic acid is dissolved, evaporated and crystallized, and dried to obtain purified 2,5-furanyl dicarboxylic acid.

[0015] The loaded particles and carbon dioxide react in a fluidized bed reactor at a temperature of 260℃~320℃ and a pressure of 0.6~1.2MPa. The carbon dioxide gas, after being distributed by a gas distributor, propels the loaded particles into a fluidized state at high speed and uniformly. The carbon dioxide gas after the reaction is cooled and dust removed and can be recycled.

[0016] The advantages and beneficial effects of this invention are as follows: This invention provides a system for batch production of 2,5-furandicarboxylic acid using furoate as a raw material. First, reactants and catalysts are loaded onto inert particles to prepare supported particles. These supported particles then react with carbon dioxide gas in a specially designed fluidized bed reactor to generate 2,5-furandicarboxylic acid. This promotes interphase mass transfer, increases the reaction rate and conversion rate, and simultaneously avoids the adhesion and agglomeration of reaction products. The loaded particles after reaction are processed to achieve the reuse of the inert particles. The reaction products are dissolved in water and subjected to a series of purification operations to finally obtain 2,5-furandicarboxylic acid with high purity. This process employs multiple energy-saving measures, ensuring reaction conversion rate while reducing energy consumption, which is conducive to large-scale industrial production. Attached Figure Description

[0017] Figure 1 This is a structural block diagram of a system for batch production of 2,5-furandicarboxylic acid using furoate as a raw material, according to one embodiment of the present invention. Figure 2 This is a schematic diagram of the structure of the loaded particle preparation unit in this invention; Figure 3This is a schematic diagram of the structure of the reaction unit in this invention; Figure 4 This is a schematic diagram of the product separation unit in this invention; Figure 5 This is a schematic diagram of the product refining unit in this invention; In the diagram: 1-Crusher, 2-Salt dissolving tank, 3-Mother liquor feed pump, 4-Feed filter, 5-Loaded process vessel, 6-Centrifugal filter, 7-Mother liquor recovery tank, 8-Mother liquor recovery pump, 9-Recovery liquid filter, 10-Double cone dryer, 11-Boiled bed reactor, 111-Gas distributor, 112-Jacketed thermostatic system, 113-Reaction temperature control system, 114-Reaction temperature monitoring sensor, 115-Reactor differential pressure monitoring system, 116-Reactor pressure control system, 117-Wire mesh filter, 118-Metal hose, 12-Carbon dioxide heat exchange system, 13-Cyclone separator, 14-Bag filter, 15-Heat pump system, 16-Condenser, 17-Gas-liquid separator, 18-Carbon dioxide compressor, 19-Flow control system, 20-Electric heater, 21-Primary washing vessel, 22-Primary centrifugal filter, 23-nth solution tank. 24-n-time washing vessel, 25-n-time centrifugal filter, 26-primary solution tank, 27-primary solution lift pump, 28-n-time solution lift pump, 29-automatic backwash filter, 30-primary filtrate tank, 31-decolorization feed pump, 32-activated carbon adsorption tank, 33-decolorization filtrate tank, 34-reverse osmosis feed pump, 35-reverse osmosis system, 36-recycled water tank, 37-refined brine tank, 38-acidification tank feed pump, 39-acidification tank, 40-crude product centrifugal filter, 41-secondary dissolution tank, 42-evaporation crystallization feed pump, 43-MVR evaporation crystallization system, 44-product centrifugal filter, 45-product double cone dryer. Detailed Implementation

[0018] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be described in detail below with reference to the accompanying drawings and specific embodiments.

[0019] like Figure 1As shown, one embodiment of the present invention provides a batch production system for 2,5-furandicarboxylic acid using furoate as raw material, including a supported particle preparation unit, a reaction unit, a product separation unit, and a product purification unit. The supported particle preparation unit immerses inert particles in a mother liquor prepared by dissolving furoate and a catalyst in a solvent, ensuring thorough wetting. The wetting particles are then dried to obtain supported particles loaded with furoate and the catalyst. The reaction unit is used to fully contact and react the supported particles with carbon dioxide under set temperature and pressure conditions, converting furoate into furandicarboxylic acid, while the byproduct water can be reacted. The process involves removing inert particles; the product separation unit immerses the reacted loaded particles in a solvent to separate furanyl dicarboxylate from the inert particles, allowing for the recycling of the inert particles; the product refining unit filters, decolorizes, and concentrates the solution from the product separation unit, then adds acid for acidification, converting furanyl dicarboxylate into 2,5-furanyl dicarboxylic acid. The 2,5-furanyl dicarboxylic acid precipitates due to its solubility in water, yielding crude 2,5-furanyl dicarboxylic acid. This crude 2,5-furanyl dicarboxylic acid is then dissolved again, evaporated, and crystallized to obtain moist refined 2,5-furanyl dicarboxylic acid, which is then dried to obtain the final product.

[0020] like Figure 2 As shown in the embodiment of the present invention, the loaded particle preparation unit includes a salt dissolving tank 2, a fluid conveying device, a loading process vessel 5, a centrifugal filter 6, a fluid recovery device, and a drying device. The salt dissolving tank 2 is connected to the loading process vessel 5 via the fluid conveying device. The loading process vessel 5 is connected to the centrifugal filter 6 via a pipeline. The centrifugal filter 6 is connected to the salt dissolving tank 2 via the fluid recovery device. The salt dissolving tank 2 is used to dissolve solid salt and prepare a mother liquor. The fluid conveying device is used to convey the mother liquor to the loading process vessel 5, which is used to immerse inert particles in the mother liquor to obtain loaded particles. The centrifugal filter 6 is used to separate the loaded particles and the mother liquor. The fluid recovery device is used to return the mother liquor to the salt dissolving tank 2. The drying device is used to dry the loaded particles. Preferably, the drying device is a double-cone dryer 10.

[0021] Furthermore, the loaded particle preparation unit also includes a crusher 1, which is used to crush solid salt into fine particles and then inject them into the salt dissolving tank 2. The salt dissolving tank 2 is equipped with a stirrer to stir the solution and accelerate the dissolution of solid salt. The fluid conveying equipment includes a conveying pipeline and a mother liquor feed pump 3 and a feed filter 4 installed on the conveying pipeline; the fluid recovery equipment includes a mother liquor recovery tank 7, a mother liquor recovery pump 8, and a recovery liquid filter 9. The mother liquor recovery tank 7 is connected to a centrifugal filter 6 through a recovery pipeline and is used to recover the mother liquor separated by the centrifugal filter 6. The mother liquor recovery tank 7 is connected to the salt dissolving tank 2 through a circulation pipeline, and the mother liquor recovery pump 8 and the recovery liquid filter 9 are sequentially installed on the circulation pipeline.

[0022] Specifically, furoate A and catalyst B, which have the same alkali metal cation, are mixed in a certain proportion, crushed into fine particles by crusher 1, and then injected into salt dissolving tank 2. The solution used for dissolution is the mother liquor for subsequent processes. If insufficient, deionized water is added according to the analytical data. In this embodiment, catalyst B is carbonate. Salt dissolving tank 2 is equipped with a stirrer to accelerate the dissolution of solid salt. The prepared mother liquor is sent to feed filter 4 by mother liquor feed pump 3, and the filtered mother liquor flows into loading process vessel 5. In loading process vessel 5, after a period of time, inert particles C are fully wetted by mother liquor and become loaded particles D. After complete wetting, the loaded particles and mother liquor are unloaded into centrifugal filter 6. After high-speed centrifugation, the moisture content of the loaded particles is about 20%~40%. The wetted loaded particles are placed in double cone dryer 10 and dried at 100~120°C under normal pressure. The mother liquor separated from centrifugal filter 6 flows into mother liquor recovery tank 7. The mother liquor is pressurized by the mother liquor recovery pump 8, filtered by the recovery liquid filter 9, and then enters the salt dissolving tank 2 for reuse in the loading process vessel 5. The entire loading particle preparation unit is operated in batches.

[0023] like Figure 3 As shown, in an embodiment of the present invention, the reaction unit includes a fluidized bed reactor 11, a carbon dioxide heat exchange system 12, a heat pump system 15, a condenser 16, and a gas-liquid separator 17. The fluidized bed reactor 11 and the gas-liquid separator 17 are connected by a carbon dioxide delivery pipeline and a carbon dioxide recovery pipeline to form a circulating delivery pipeline. The fluidized bed reactor 11 is used to load particles to react with carbon dioxide. The carbon dioxide output from the fluidized bed reactor 11 enters the gas-liquid separator 17 through the carbon dioxide recovery pipeline and the condenser 16. The carbon dioxide heat exchange system 12 and the heat pump system 15 are both connected between the carbon dioxide delivery pipeline and the carbon dioxide recovery pipeline for heat exchange. A carbon dioxide compressor 18 is provided on the carbon dioxide delivery pipeline to compress the delivered carbon dioxide gas.

[0024] In an embodiment of the present invention, a gas distributor 111 is provided at the bottom of the fluidized bed reactor 11. The gas distributor 111 is connected to a carbon dioxide delivery pipeline via a metal hose 118. An electric heater 20 is provided on the carbon dioxide delivery pipeline. The electric heater 20 is connected to a reaction temperature control system 113. The reaction temperature control system 113 detects the reaction temperature inside the fluidized bed reactor 11 via a reaction temperature monitoring sensor 114. The power of the electric heater 20 is controlled by the measured temperature inside the fluidized bed reactor 11. A jacketed constant temperature system 112 is provided on the outside of the fluidized bed reactor 11 to provide temperature compensation for the fluidized bed reactor 11. A wire mesh filter 117 and a reactor differential pressure monitoring system 115 for detecting the pressure difference between the upper and lower sides of the wire mesh filter 117 are provided at the top of the fluidized bed reactor 11. When the wire mesh filter 117 becomes clogged, the reactor differential pressure monitoring system 115 sends an alarm to the system. A reactor pressure control system 116 is provided at the top of the fluidized bed reactor 11 to control the gas pressure inside the fluidized bed reactor 11.

[0025] In an embodiment of the present invention, a cyclone separator 13 and a bag filter 14 are provided on the carbon dioxide recovery pipeline, and the cyclone separator 13 and the bag filter 14 are located between the carbon dioxide heat exchange system 12 and the heat pump system 15; a flow control system 19 is provided between the carbon dioxide conveying pipeline and the carbon dioxide recovery pipeline. When the pressure on the carbon dioxide conveying pipeline exceeds a set value, the flow control system 19 releases the carbon dioxide in the carbon dioxide conveying pipeline into the carbon dioxide recovery pipeline.

[0026] Specifically, such as Figure 2As shown, the dried loaded particles from the loaded particle preparation unit are loaded into the fluidized bed reactor 11 of the reaction unit. The reaction temperature inside the fluidized bed reactor 11 is 260℃~320℃. CO2 gas at 0.6~1.2MPa, after being acted upon by the gas distributor 111, propels the loaded particles into a fluidized state at high speed and uniformly. At this time, the loaded particles are in full and uniform contact with carbon dioxide, which enhances the interphase mass transfer and improves the rate and conversion rate of furoate to furanyl dicarboxylate. The fluidized loaded particles rise to the upper section of the reactor. Due to the reactor's expansion design, the CO2 gas flow rate decreases, and the loaded particles lose their upward propulsion and fall to the lower section of the reactor. The loaded particles thus move back and forth between the upper and lower sections of the fluidized bed reactor 11, and the reaction time lasts for 6~24 hours. The reactor temperature is controlled by the reaction temperature control system 113 by adjusting the power of the electric heater 20. Heat loss from the reactor is compensated by the jacketed constant temperature system 112. The reactor pressure is regulated by the reactor pressure control system 116. The CO2 gas after the reaction, carrying the water produced in the reaction, exits the reactor through a wire mesh filter 117. To prevent overpressure in the reactor caused by clogging of the wire mesh filter 117, a reactor differential pressure monitoring system 115 is installed inside the reactor. The CO2 gas exiting the reactor undergoes thorough heat exchange with the CO2 gas entering the reactor in the carbon dioxide heat exchange system 12. After being depressurized and cooled, the gas passes through a cyclone separator 13 and a bag filter 14 to remove fine dust. Heat is then recovered by a heat pump system 15, and the gas is further cooled to 35°C~40°C by a condenser 16. At this point, the water carried by the CO2 gas condenses and precipitates out. The water is then removed in the gas-liquid separator 17 and is recycled for the next cycle. The recycled CO2 gas is pressurized to the required system pressure by a carbon dioxide compressor 18. CO2 gas M can be added to the gas-liquid separator 17 as needed. The required CO2 gas flow rate into the reactor is precisely regulated by a flow control system 19, and excess CO2 gas is returned to the inlet of the condenser 16 via a bypass. The CO2 gas entering the reactor is first preheated by heat recovered from the heat pump system 15, then further heated by the CO2 gas exiting the reactor through the carbon dioxide heat exchange system 12, and finally heated to the required reaction temperature by the electric heater 20. The entire reaction unit operates in batches. It is designed that only the fluidized bed reactor 11 needs to be depressurized during loading and unloading of particles, while the other equipment can maintain pressure, thus achieving energy saving.

[0027] like Figure 4As shown in the embodiment of the present invention, the product separation unit includes n-stage separation units connected in sequence. Each stage includes a washing tank, a centrifugal filter, and a solution tank. The bottom of the washing tank is connected to the centrifugal filter through a pipeline, and the top of the washing tank is connected to the solution tank of the next stage through a pipeline equipped with a solution lift pump 27. The load particles washed in the washing tank enter the centrifugal filter for filtration. The filtered load particles enter the washing tank of the next stage separation unit. The solution filtered by the centrifugal filter enters the solution tank, and the solution in the solution tank is transported to the washing tank of the previous stage through the solution lift pump 27.

[0028] Specifically, after the reaction is complete, the reaction product N (loaded particles) is immersed in a primary washing tank 21. The solution used for immersion is discharged from the next washing tank, and the subsequent process follows the same principle. The material discharged from the primary washing tank 21 is separated by a primary centrifugal filter 22, and the loaded particles are then fed into the next washing tank, while the solution enters the nth solution tank 23. The solution discharged from the next washing tank is then used to immerse the loaded particles in the previous washing tank, and the subsequent process continues in this manner. Since the loaded particles fed into the primary washing tank 21 contain the most reaction products, and the concentration of reaction products in the solution used is also high, the solution in the nth solution tank 23 has the highest concentration of reaction products and can be sent to the product purification unit. The inert particles discharged from the nth washing tank contain the least amount of raw materials and reactants and can be sent to the loaded particle preparation unit for reuse. Reclaimed water or deionized water E can be injected into the nth washing tank. The entire product separation unit operates in batch mode.

[0029] Specifically, the product separation unit is washed 1 to 10 times, preferably 2 to 3 times.

[0030] like Figure 5 As shown in the embodiment of the present invention, the product refining unit includes a filtration device, a reverse osmosis system 35, a fluid conveying device, an acidification tank 39, a dissolving device, an evaporation crystallization system, and a drying device arranged sequentially along the process flow. The filtration device is used to filter and decolorize the salt solution sent from the product separation unit; the reverse osmosis system is used to concentrate the salt solution; the fluid conveying device is used to send the concentrated refined brine into the acidification tank 39, which is used to acidify the refined brine. Furan dicarboxylate is converted into 2,5-furan dicarboxylic acid under acidic conditions and precipitates due to saturation. After most of the water is removed by the crude product centrifugal filter 40, it becomes crude 2,5-furan dicarboxylic acid. The crude 2,5-furan dicarboxylic acid is then dissolved, crystallized, and dried sequentially by the dissolving device, the evaporation crystallization system, and the drying device to obtain refined 2,5-furan dicarboxylic acid.

[0031] In this embodiment, the filtration equipment includes an automatic backwash filter 29, a primary filtrate tank 30, a decolorizing feed pump 31, an activated carbon adsorption tank 32, and a decolorizing filtrate tank 33 connected in sequence; the reverse osmosis system 35 is connected to the decolorizing filtrate tank 33 via a reverse osmosis feed pump 34; the reverse osmosis system 35 is also connected to a recycled water tank 36. The fluid transport equipment includes a refined brine tank 37 and an acidification tank feed pump 38, with the refined brine tank 37 supplying refined brine to the acidification tank 39 via the acidification tank feed pump 38. The dissolving equipment includes a secondary dissolving tank 41 and an evaporation crystallization feed pump 42, with the secondary dissolving tank 41 supplying the dissolving solution to the evaporation crystallization system via the evaporation crystallization feed pump 42. The evaporation crystallization system includes an MVR evaporation crystallization system 43 connected to a product centrifugal filter, and the drying equipment is a product double-cone dryer 45.

[0032] Specifically, the solution from the product separation unit is finely filtered by the automatic backwash filter 29 and then sent to the activated carbon adsorption tank 32 for decolorization, adsorbing colored impurities from the solution. The clean, colorless solution is concentrated by the reverse osmosis system 35. The water produced by this process can be reused in the final washing of the loaded particles in the product separation unit, maximizing water reuse. Simultaneously, the increased solution concentration reduces the energy consumption of the MVR evaporation crystallization system 43 and the acid consumption of subsequent acidification. The concentrated refined brine is sent to the acidification tank 39, where hydrochloric acid F is added based on analytical data. This converts furanyl dicarboxylate into 2,5-furanyl dicarboxylic acid under acidic conditions, causing it to precipitate due to saturation. After most of the water is removed by the crude product centrifugal filter 40, it becomes crude 2,5-furanyl dicarboxylic acid H. Crude 2,5-furandicarboxylic acid H is redissolved in a secondary dissolution tank 41 and recrystallized into higher purity 2,5-furandicarboxylic acid via an MVR evaporation crystallization system 43. After most of the water is separated by a product centrifugal filter 44, the wet 2,5-furandicarboxylic acid G is fed into a product double-cone dryer 45 for drying, yielding the final product, 2,5-furandicarboxylic acid. In the product refining unit, the production process from the nth solution lift pump 28 to the MVR evaporation crystallization system 43 can be continuously operated by matching the batch capacity and operating time of the preceding units, thereby reducing the equipment size of the product refining unit and lowering the initial investment. The product centrifugal filter 44 and the product double-cone dryer 45 are operated in batches.

[0033] In the embodiments of this invention, when the loaded particles react with carbon dioxide, the loaded particles become fluidized under the action of the carbon dioxide gas flow, greatly increasing the contact area between different phases, promoting interphase mass transfer, improving the reaction rate and conversion rate, and simultaneously preventing the adhesion and agglomeration of reaction products. A heat exchanger system and a heat pump system are used to achieve heat exchange between the carbon dioxide gas entering and exiting the fluidized bed reactor, realizing efficient energy utilization and achieving the goal of reducing energy consumption. The carbon dioxide heat exchange system includes multiple heat exchangers connected in series or parallel, suitable for different gas temperature ranges. The flow rate of carbon dioxide entering the fluidized bed reactor is precisely controlled by a flow control system, and the adjustment method adopts bypass regulation to meet the carbon dioxide gas demand of the fluidized bed reactor.

[0034] Based on the above design concept, another embodiment of the present invention provides a process flow for batch production of 2,5-furandicarboxylic acid using furoate as a raw material as described above, including the following steps: A solution is prepared by dissolving furoate and catalyst in a solvent in a predetermined ratio. Inert particles are immersed in a solution to load furoate and catalyst onto the inert particles, thus obtaining loaded particles. The loaded particles are brought into full contact with carbon dioxide under set temperature and pressure conditions to react and convert furoate into furanyl dicarboxylate. The loaded particles after the reaction are immersed in a solvent to separate furan dicarboxylate from the inert particles, and the inert particles are recycled. The solution after separation of inert particles is acidified to convert furanyl dicarboxylate into crude 2,5-furanyl dicarboxylic acid; the crude 2,5-furanyl dicarboxylic acid is dissolved, evaporated and crystallized, and dried to obtain purified 2,5-furanyl dicarboxylic acid.

[0035] Specifically, the loaded particles and carbon dioxide react in a fluidized bed reactor at a temperature of 260℃~320℃ and a pressure of 0.6~1.2MPa. The carbon dioxide gas, after being distributed by a gas distributor, propels the loaded particles into a fluidized state at high speed and uniformly. The carbon dioxide gas after the reaction is cooled and dust removed and can be recycled.

[0036] In the embodiments of the present invention, inert particles refer to spherical or near-spherical particles with a porous structure, which have a certain mechanical strength and will not break in large quantities due to collisions in the reaction unit; inert particles will not soften or deform in high-temperature environments below 850°C; inert particles will not break in an environment of 3MPa; the most important characteristic of inert particles is that they will not chemically react with furfuryl salts, catalysts, carbon dioxide, 2,5-furandicarboxylic acid and water; Furthermore, the supported particles are inert particles loaded with a certain proportion of furoate and catalyst; the cation of furoate can be one or more alkali metal ions; the catalyst is a carbonate that has the same alkali metal cation as the furoate.

[0037] This invention provides a process for batch production of 2,5-furandicarboxylic acid using furoate as a raw material. The process involves loading reactants and catalyst onto inert particles to prepare supported particles. These supported particles then react with carbon dioxide gas in a specially designed fluidized bed reactor to generate 2,5-furandicarboxylic acid. This process promotes interphase mass transfer, increases the reaction rate and conversion rate, and simultaneously prevents product aggregation and agglomeration. The loaded particles are then processed to allow for the reuse of the inert particles. The reaction product is dissolved in water and undergoes a series of purification operations to finally obtain high-purity 2,5-furandicarboxylic acid. This process employs multiple energy-saving measures, ensuring high reaction conversion rate while reducing energy consumption, thus facilitating large-scale industrial production.

[0038] The above embodiments merely illustrate the basic principles and characteristics of the present invention. The present invention is not limited to the above embodiments. Various changes and modifications can be made to the present invention without departing from its spirit and scope, and all such changes and modifications fall within the scope of the present invention as claimed. The scope of protection of the present invention is defined by the appended claims and their equivalents.

Claims

1. A system for batch production of 2,5-furandicarboxylic acid using furoate as raw material, characterized in that, include: The loaded particle preparation unit involves immersing inert particles in a mother liquor made by dissolving furoate and catalyst in a solvent; then drying the immersed particles to obtain loaded particles loaded with furoate and catalyst. The reaction unit is used to fully contact and react the supported particles with carbon dioxide under set temperature and pressure conditions to convert furoate into furan dicarboxylate. The product separation unit is used to immerse the reacted loaded particles in a solvent to separate furan dicarboxylate from the inert particles, allowing the inert particles to be recycled. In the product refining unit, the solution from the product separation unit is acidified to convert furanyl dicarboxylate into crude 2,5-furanyl dicarboxylic acid; the crude 2,5-furanyl dicarboxylic acid is then dissolved again, evaporated and crystallized, and dried to obtain refined 2,5-furanyl dicarboxylic acid. The loaded particle preparation unit includes a salt dissolving tank (2), a fluid conveying device, a loaded process vessel (5), a centrifugal filter (6), a fluid recovery device, and a drying device. The salt dissolving tank (2) is connected to the loaded process vessel (5) through the fluid conveying device. The loaded process vessel (5) is connected to the centrifugal filter (6) through a pipeline. The centrifugal filter (6) is connected to the salt dissolving tank (2) through the fluid recovery device. The salt dissolving tank (2) is used to dissolve solid salt and prepare mother liquor. The fluid conveying device is used to transport the mother liquor to the loaded process vessel (5). The loaded process vessel (5) is used to immerse inert particles in the mother liquor to obtain loaded particles. The centrifugal filter (6) is used to separate the loaded particles and the mother liquor. The fluid recovery device is used to transport the mother liquor back to the salt dissolving tank (2). The drying device is used to dry the loaded particles. The reaction unit includes a fluidized bed reactor (11), a carbon dioxide heat exchange system (12), a heat pump system (15), a condenser (16), and a gas-liquid separator (17). The fluidized bed reactor (11) and the gas-liquid separator (17) are connected by a carbon dioxide delivery pipeline and a carbon dioxide recovery pipeline to form a circulating delivery pipeline. The fluidized bed reactor (11) is used to load particles to react with carbon dioxide. The carbon dioxide output from the fluidized bed reactor (11) enters the gas-liquid separator (17) through the condenser (16) via the carbon dioxide recovery pipeline. The carbon dioxide heat exchange system (12) and the heat pump system (15) are both connected between the carbon dioxide delivery pipeline and the carbon dioxide recovery pipeline for heat exchange. A carbon dioxide compressor (18) is provided on the carbon dioxide delivery pipeline to compress the delivered carbon dioxide gas. The product separation unit includes n-stage separation units connected in sequence. Each stage includes a washing tank, a centrifugal filter and a solution tank. The bottom of the washing tank is connected to the centrifugal filter through a pipeline, and the top of the washing tank is connected to the solution tank of the next stage through a pipeline with a solution lift pump (27). The load particles washed by the washing tank enter the centrifugal filter for filtration. The filtered load particles enter the washing tank of the next stage separation unit. The solution filtered by the centrifugal filter enters the solution tank. The solution in the solution tank is transported to the washing tank of the previous stage through the solution lift pump (27). The product refining unit includes a filtration device, a reverse osmosis system, a fluid conveying device, an acidification tank (39), a dissolving device, an evaporation crystallization system, and a drying device arranged sequentially along the process flow. The filtration device is used to filter and decolorize the salt solution sent from the product separation unit; the reverse osmosis system is used to concentrate the salt solution; the fluid conveying device is used to send the concentrated refined brine into the acidification tank (39), which is used to acidify the refined brine. Furan dicarboxylate is converted into 2,5-furan dicarboxylic acid under acidic conditions and precipitates due to saturation. After most of the water is removed by the crude product centrifugal filter (40), it becomes crude 2,5-furan dicarboxylic acid. Crude 2,5-furandicarboxylic acid is sequentially dissolved, crystallized, and dried using a dissolving device, an evaporation crystallization system, and a drying device to obtain refined 2,5-furandicarboxylic acid.

2. The batch production system for 2,5-furandicarboxylic acid using furoate as raw material according to claim 1, characterized in that, The loaded particle preparation unit also includes a crusher (1), which is used to crush solid salt into fine particles and then inject them into the salt dissolving pool (2). The salt dissolving pool (2) is equipped with a stirrer to stir the solution and accelerate the dissolution of solid salt. The fluid transport equipment includes a transport pipeline and a mother liquor feed pump (3) and a feed filter (4) installed on the transport pipeline; the fluid recovery equipment includes a mother liquor recovery tank (7), a mother liquor recovery pump (8) and a recovery liquid filter (9), wherein the mother liquor recovery tank (7) is connected to the centrifugal filter (6) through a recovery pipeline and is used to recover the mother liquor separated by the centrifugal filter (6); the mother liquor recovery tank (7) is connected to the salt dissolving tank (2) through a circulation pipeline, and the mother liquor recovery pump (8) and the recovery liquid filter (9) are sequentially installed on the circulation pipeline.

3. The batch production system for 2,5-furandicarboxylic acid using furoate as raw material according to claim 1, characterized in that, The bottom of the fluidized bed reactor (11) is provided with a gas distributor (111), which is connected to the carbon dioxide delivery pipeline through a metal hose (118). An electric heater (20) is provided on the carbon dioxide delivery pipeline, which is connected to a reaction temperature control system (113). The reaction temperature control system (113) detects the reaction temperature inside the fluidized bed reactor (11) through a reaction temperature monitoring sensor (114). The fluidized bed reactor (11) is provided with a jacketed temperature control system (112) on the outside, which is used to provide temperature compensation for the fluidized bed reactor (11). The upper part of the fluidized bed reactor (11) is provided with a wire mesh filter (117) and a reactor differential pressure monitoring system (115) for detecting the pressure difference between the upper and lower sides of the wire mesh filter (117). When the wire mesh filter (117) is blocked, the reactor differential pressure monitoring system (115) will alarm. The top of the fluidized bed reactor (11) is provided with a reactor pressure control system (116), which is used to control the gas pressure inside the fluidized bed reactor (11).

4. The batch production system for 2,5-furandicarboxylic acid using furoate as raw material according to claim 1, characterized in that, The carbon dioxide recovery pipeline is equipped with a cyclone separator (13) and a bag filter (14), which are located between the carbon dioxide heat exchange system (12) and the heat pump system (15). A flow control system (19) is provided between the carbon dioxide delivery pipeline and the carbon dioxide recovery pipeline. When the pressure on the carbon dioxide delivery pipeline exceeds the set value, the flow control system (19) releases the carbon dioxide in the carbon dioxide delivery pipeline into the carbon dioxide recovery pipeline.

5. A process flow for batch production of 2,5-furandicarboxylic acid using furoate as raw material according to any one of claims 1-4, characterized in that, Includes the following steps: A solution is prepared by dissolving furoate and catalyst in a solvent in a predetermined ratio. Inert particles are immersed in a solution to load furoate and catalyst onto the inert particles, thus obtaining loaded particles. The loaded particles are brought into full contact with carbon dioxide under set temperature and pressure conditions to react and convert furoate into furanyl dicarboxylate. The loaded particles after the reaction are immersed in a solvent to separate furan dicarboxylate from the inert particles, and the inert particles are recycled. The solution after separating inert particles is acidified to convert furanyl dicarboxylate into crude 2,5-furanyl dicarboxylic acid; the crude 2,5-furanyl dicarboxylic acid is dissolved, evaporated and crystallized, and dried to obtain purified 2,5-furanyl dicarboxylic acid.

6. The process flow according to claim 5, characterized in that, The loaded particles and carbon dioxide react in a fluidized bed reactor at a temperature of 260℃~320℃ and a pressure of 0.6~1.2MPa. The carbon dioxide gas, after being distributed by a gas distributor, propels the loaded particles into a fluidized state at high speed and uniformly. The carbon dioxide gas after the reaction is cooled and dust removed and can be recycled.

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