Process for preparing bisphenol A by continuously reinforcing condensation reaction of acetone and phenol

Abstract

The invention relates to a process for preparing bisphenol A by continuously reinforcing condensation reaction of acetone and phenol. The bisphenol A is obtained by feeding phenol and acetone into a fixed bed membrane reactor for condensation reaction, in-situ dehydration, concentration, solvent recovery, crystallization and separation. In the process, a fixed bed membrane reactor is filled with a catalyst to catalyze the condensation reaction of reactants acetone and phenol; meanwhile, the wall surface of the fixed bed membrane reactor is made of a CHA molecular sieve membrane material with a high silica-alumina ratio, and water generated by reaction is removed in situ. According to the process technology, water generated in a bisphenol A reaction system can be effectively removed in situ, the water content in the product is reduced to 0.5 wt% or below, and compared with a conventional bisphenol A production process, the energy consumption for dehydration and separation of the product bisphenol A is reduced by 35-45%. The timely removal of water reduces the influence on the resin catalyst, and the service life of the resin catalyst is prolonged by 2-3 times, so that the reaction system maintains high selectivity and high product yield.

Description

Technical Field

[0001] The invention relates to a process for preparing bisphenol A by strengthening the condensation reaction of acetone and phenol, and in particular to a process for preparing bisphenol A by continuously strengthening the condensation reaction of acetone and phenol by combining in-situ catalysis with in-situ dehydration.

[0002] The purpose of the present invention is to propose a process for preparing bisphenol A by continuously strengthening the condensation reaction of acetone and phenol by combining in-situ catalysis with in-situ dehydration. Bisphenol A is obtained by feeding phenol and acetone into a fixed bed membrane reactor for condensation reaction, in-situ dehydration, concentration, solvent recovery, crystallization and separation. In the process, the fixed bed membrane reactor is filled with a catalyst (solid particles) to catalyze the condensation reaction of the reactants acetone and phenol; at the same time, the wall of the fixed bed membrane reactor is a molecular sieve with a CHA topological structure as a membrane to remove the water generated by the reaction in situ. The process technology can effectively remove the water generated in the bisphenol A reaction system in situ, so that the water content in the product is reduced to less than 0.5wt%. Compared with the conventional bisphenol A production process, the energy consumption of dehydration and separation of the product bisphenol A is reduced by 35-45%. The timely removal of water reduces the impact on the resin catalyst, and the life of the resin catalyst is increased by 2-3 times, so that the reaction system maintains high selectivity and high product yield. Background Art

[0003] Bisphenol A (BPA), chemical name 2,2-bis(4-hydroxyphenyl)propane, is a widely used organic chemical raw material, mainly used in the production of polycarbonate, epoxy resin and other polymer materials. At present, ion exchange resin is used as a catalyst in the industry to catalyze the synthesis of bisphenol A from phenol and acetone. The process is simple, has low corrosion to equipment, and emits less waste. The catalyst used in this process is an ion exchange resin obtained by sulfonation or thiol modification with styrene or substituted styrene as a monomer, divinylbenzene as a crosslinker, and liquid paraffin as a porogen. It has the characteristics of high catalytic activity and good selectivity. However, the water generated in the condensation reaction of acetone and phenol leads to a decrease in the activity of the resin catalyst, especially in the middle and late stages of the reaction, the catalytic activity of the resin catalyst is greatly reduced, resulting in a decrease in the yield of bisphenol A; and the reaction rate is slowed down, resulting in a decrease in the production efficiency of bisphenol A. At the same time, the water generated by the condensation reaction will also increase the energy consumption of the separation and purification process of the condensation product bisphenol A.

[0004] In the industrial production of bisphenol A, the resin catalyst that absorbs water during the reaction is usually subjected to regular dehydration and regeneration treatment to improve the activity and reaction rate of the catalyst. The process is complicated, and it is necessary to stop the feed to interrupt the reaction, empty the reaction raw materials and products in the reactor, and then perform a resin dehydration treatment on the resin catalyst bed by purging with a high-temperature inert atmosphere and eluting with an eluent phenol. The amount of eluent phenol used in the dehydration process is large, which increases equipment and operating costs. At the same time, this intermittent non-continuous dehydration treatment operation for the resin catalyst has a long treatment time and cannot continuously treat the water generated in the removal reaction, resulting in low bisphenol A production efficiency. Although the resin catalyst can be restored to use after dehydration treatment, its essence is to separate the phenol acetone condensation reaction process from the dehydration treatment process, and it is not possible to achieve simultaneous dehydration treatment in the phenol acetone condensation reaction. This step-by-step reaction and dehydration process causes the water generated in the first step of the phenol-acetone condensation reaction to be unable to be removed in time, but requires the subsequent second step of dehydration to complete the activity recovery of the resin catalyst, so the water generated in the first step of the reaction will still affect the catalytic performance and life of the resin catalyst, which then leads to low efficiency in the first step of the reaction. It can be seen that this treatment method does not effectively dehydrate the water generated in the first step of the phenol-acetone condensation reaction, that is, such treatment does not play the role of strengthening the first step of the phenol-acetone condensation reaction process. And an effective method that can strengthen the phenol-acetone condensation reaction is to remove water in time during the reaction to reduce the impact of water on the resin catalyst and maintain the high catalytic performance of the resin catalyst. It can be seen that the existing bisphenol A production technology has problems such as low production efficiency and low product yield caused by the inability to remove water in time in the reaction.

[0005] In view of the problems existing in the intermittent and discontinuous dehydration of the above-mentioned resin catalyst, an in-situ dehydration method is adopted, that is, the water generated by the condensation reaction is immediately removed during the resin catalytic condensation reaction to reduce the influence of water on the resin catalyst, so that the resin catalyst maintains a high catalytic activity and generates more bisphenol A; at the same time, timely removal of the water generated in the reaction can promote the condensation chemical reaction of acetone and phenol to generate bisphenol A, which is beneficial to increase the reaction rate of bisphenol A. In industry, attempts are made to adopt the method of reactive distillation, that is, combining the phenol-acetone condensation reaction with the water distillation separation process, and using the relative volatility difference between water and other components to achieve water removal. Although this method can continuously remove the water generated in the reaction in situ, due to the high freezing point and small relative volatility difference of phenol, acetone and product bisphenol A, the water removal effect in the reactive distillation process is poor and the reaction energy consumption is high, and the phenol-acetone condensation reaction process cannot be effectively strengthened. The key point to solve this problem is to continuously strengthen the dehydration process in the reaction to achieve the production of bisphenol A.

[0006] It can be seen that the in-situ dehydration method can improve the reaction rate and yield of bisphenol A, which is of great significance to the development of bisphenol A production technology. The membrane reactor, that is, the reactor equipped with membrane materials, can selectively pass the by-products produced by the reaction through the membrane materials and flow out of the reactor while the reaction is in progress, thereby realizing the in-situ separation of products and by-products. At present, there are few reports on membrane reactors for bisphenol A reactions, especially membrane reactors for in-situ dehydration of bisphenol A reactions. The key to the industrial application of bisphenol A membrane reactors lies in membrane materials with high water permeability selectivity and membrane reactors.

[0007] In terms of membrane materials, membrane materials that can selectively permeate water are divided into two types: organic membranes and inorganic membranes.

[0008] Organic membrane materials, mainly represented by polyvinyl alcohol separation membranes, have poor water permeability and low packing density, and poor in-situ dehydration effect. The literature (Chemical Reaction Engineering and Technology, 1995, 11 (1): 86-91) reported that the use of polyimide pervaporation membranes to continuously remove the product water of the reaction effectively accelerated the reaction rate and increased the single-pass yield of bisphenol A. However, due to the weak acidity of phenol in the phenol-acetone condensation reaction, the organic membrane material will swell and deform, and even the skeleton structure of the membrane material will change or be destroyed, resulting in a decrease in the stability of the membrane material and a shortened service life, which cannot meet the requirements of industrial use.

[0009] Inorganic membrane materials, especially molecular sieve membranes, have excellent dehydration performance and are not easy to swell, and have good industrial application prospects. The literature Industrial & Engineering Chemistry Research, 2013, 52 (19): 6336-6342. It reports the use of NaA molecular sieves for in-situ dehydration of the esterification reaction of acetic acid and n-propanol. The literature Journal of Membrane Science, 2015, 486: 189-194 reports the use of a membrane reactor with NaA molecular sieves for in-situ dehydration of methanol etherification reaction. The literature (Journal of Chemical Engineering of Colleges and Universities, 2021, 35 (4): 649-656. The NaA molecular sieve obtained by hydrothermal synthesis is attached to the hollow fiber α-Al 2 O 3 The support was used as a molecular sieve membrane element to construct a pervaporation membrane reactor for liquid-phase etherification of ethanol and tert-butanol, which significantly improved the selectivity and yield of the product.

[0010] In terms of membrane reactors, patent US20090170964A1 discloses a technology for in-situ water dehydration of reactions (such as Fischer-Tropsch reaction) using a fixed bed membrane reactor, wherein the reactor includes a membrane assembly having a fixed water permeable membrane in fluid communication with a reaction zone, allowing water produced in the reaction zone to be selectively removed from the reaction zone as a permeate flow, while allowing the retained reaction products to remain in the reaction zone and be discharged as a retained flow.

[0011] During the condensation reaction of phenol and acetone catalyzed by the resin catalyst, some acidic sites in the resin catalyst are free in the mixture of reactants and products, resulting in an acidic pH value of the reaction system and a weak acidity of the reactant phenol. Therefore, it is not guaranteed that the in-situ dehydration membrane can function under acidic conditions, that is, the in-situ dehydration membrane material needs to have a certain acid resistance. The NaA molecular sieve structure of the conventional NaA molecular sieve membrane is unstable, and the aluminum in its skeleton is easily removed from the molecular sieve skeleton by reacting with acid, resulting in the enlargement of the pores of the NaA molecular sieve membrane, and other molecules can also pass through, and then the ability to selectively permeate water decreases. It can be seen that the NaA molecular sieve membrane is not suitable for in-situ dehydration treatment in the bisphenol A reaction process.

[0012] From the above review and analysis, it can be seen that in the resin-catalyzed synthesis of bisphenol A reaction system, there is no in-situ dehydration membrane material and membrane reactor suitable for the catalytic condensation reaction to produce bisphenol A. The existing reported membrane materials cannot achieve in-situ dehydration. But more importantly, it is necessary to meet the requirements of the synthesis of bisphenol A reaction process and catalytic reaction at the same time. Therefore, according to the characteristics of the in-situ dehydration process of the bisphenol A reaction, it is necessary to match the membrane material, catalytic reaction, and reaction process, and design a membrane catalysis-in-situ dehydration reactor for resin catalyst and membrane separation to strengthen the in-situ dehydration process in the reaction.

[0013] To this end, the present invention aims to solve the problems that in the process of catalyzing the condensation reaction of acetone and phenol to produce bisphenol A, the water generated by the condensation reaction occupies the active center of the resin catalyst and affects the catalytic performance, and at the same time, the water in the product consumes a lot of energy in the subsequent separation and recovery of bisphenol A. A new process for continuously strengthening the condensation reaction of acetone and phenol to produce bisphenol A is developed. Summary of the invention

[0014] The object of the present invention is to provide a process for preparing bisphenol A by continuously strengthening the condensation reaction of acetone and phenol, wherein bisphenol A is obtained by feeding phenol and acetone into a fixed-bed membrane reactor for condensation reaction, in-situ dehydration, concentration, solvent recovery, crystallization and separation. In the process, a catalyst (solid particles) is loaded in the fixed-bed membrane reactor to catalyze the condensation reaction of the reactants acetone and phenol. Meanwhile, the wall of the fixed-bed membrane reactor is a CHA molecular sieve with a high silicon-aluminum ratio as a membrane to remove water generated by the reaction in-situ.

[0015] This process technology can effectively remove the water generated in the bisphenol A reaction system in situ, reducing the energy consumption of dehydration and separation of the product bisphenol A. The timely removal of water reduces the impact on the catalyst, allowing the reaction system to maintain high selectivity and high product yield.

[0016] In order to achieve the purpose of the present invention, the technical solution adopted by the present invention is as follows:

[0017] The invention discloses a process for preparing bisphenol A by continuously intensifying the condensation reaction of acetone and phenol, wherein bisphenol A is obtained by feeding phenol and acetone into a fixed-bed membrane reactor for condensation reaction and in-situ dehydration, concentration, solvent recovery, crystallization and separation.

[0018] The present invention provides a process for continuously strengthening the condensation reaction of acetone and phenol to prepare bisphenol A, such as Figure 1 As shown, the following steps are included:

[0019] 1) Phenol and acetone are added to a fixed bed membrane reactor respectively, and condensed under the action of a resin catalyst to generate a bisphenol A product mixed liquid consisting of bisphenol A, water and other by-products;

[0020] 2) In a fixed bed membrane reactor, the bisphenol A product mixed liquid generated by the condensation is subjected to in-situ dehydration by using a CHA molecular sieve membrane material with a high silicon-aluminum ratio to allow water to pass through the fixed bed reactor to the outside of the fixed bed reactor, thereby obtaining an in-situ dehydrated bisphenol A product mixed liquid;

[0021] 3) sending the bisphenol A product mixed liquid after in-situ dehydration at the outlet of the fixed bed membrane reactor to a concentration tower for concentration;

[0022] 4) The light components obtained from the top of the concentration tower are recovered to obtain phenol and acetone, which are sent to a fixed bed membrane reactor as raw materials to continue to undergo condensation reaction under the action of a resin catalyst to produce bisphenol A;

[0023] 5) The concentrated reaction liquid obtained from the reactor of the concentration tower is sent to a crystallization reactor to be crystallized with phenol to obtain a bisphenol A adduct and a crystallization mother liquor, and then the bisphenol A adduct is sent to a dephenolization reactor to remove phenol to obtain a bisphenol A product.

[0024] The catalyst is an acidic ion exchange resin, the crosslinking degree of the acidic ion exchange resin is 1.0% to 20%, the particle size range is 0.4nm to 5.0nm, and the water content of the acidic ion exchange resin is 20% to 90% by weight of the acidic ion exchange resin.

[0025] The condensation reaction temperature of phenol and acetone in the fixed bed membrane reactor is 45-95° C., and the reaction pressure is 0.1-0.5 MPaA.

[0026] The hourly feed volume of the phenol and acetone is 0.1 to 10 times the volume of the resin catalyst.

[0027] The outside of the fixed bed membrane reactor is connected to a vacuum system, and the vacuum system controls the vacuum degree of the permeate side of the fixed bed membrane reactor to 0.1-3.0 mbar.

[0028] The preparation method of the high silicon-aluminum ratio CHA molecular sieve membrane material used in the fixed bed membrane reactor is as follows: first, a molecular sieve having a *BEA topological structure is dealuminated to obtain a *BEA molecular sieve after dealumination, and then coated on an α-Al 2 O 3 , hollow fiber, mullite, and stainless steel; then, under the action of a crystal directing agent, crystallization is performed to obtain a CHA molecular sieve membrane material with a high silicon-aluminum ratio.

[0029] The crystal-transforming directing agent is one or a combination of sodium oxide, potassium hydroxide, tetramethylammonium hydroxide, tetraethylammonium hydroxide, tetrapropylammonium hydroxide, tetrabutylammonium hydroxide, and ammonia water; the mass ratio of the crystal-transforming directing agent to the dealuminated *BEA molecular sieve is 1:5-200.

[0030] The crystallization conditions are: crystallization at 120-180° C. for 1-120 hours.

[0031] The reaction process flow of the continuous enhanced condensation reaction of acetone and phenol to prepare bisphenol A is different from the prior art in that a fixed bed membrane reactor with an in-situ dehydration function and a reaction separation and recovery process matched therewith are utilized.

[0032] The fixed bed membrane reactor (101) for continuously strengthening the condensation reaction of acetone and phenol to produce bisphenol A of the present invention is shown in the attached Figure 2 The fixed bed membrane reactor is divided into three parts. The interior of the reactor is used to fill the catalyst, and the reactants contact with the catalyst in this area to react and flow to the reactor outlet; the middle part of the reactor is a membrane material, which is used to selectively permeate the products generated inside the reactor into the vacuum system connected to the outside; the outside of the reactor is an area where the water separated by the membrane material flows and flows to the liquid collection device. The fixed bed membrane reactor (101) is filled with a resin catalyst to catalyze the condensation reaction of acetone and phenol; the middle part of the fixed bed membrane reactor is a CHA molecular sieve membrane with a high silicon-aluminum ratio to remove the water generated by the reaction.

[0033] The main innovations of the present invention are:

[0034] (1) Reaction process and fixed bed membrane reactor

[0035] The present invention proposes to combine the catalytic condensation reaction of phenol and acetone with the in-situ dehydration process, and use a fixed bed membrane reactor and a reaction process with in-situ catalytic function and in-situ dehydration function. The fixed bed membrane reactor is filled with a resin catalyst inside, and a CHA molecular sieve membrane with a high silicon-aluminum ratio is installed outside the fixed bed membrane reactor, wherein the resin catalyst catalyzes the condensation reaction of phenol and acetone to generate bisphenol A and water, and then the fixed bed membrane of the molecular sieve membrane removes the reaction product water in situ, and the bisphenol A-containing product after water removal is concentrated, solvent recovered, crystallized, and separated to obtain bisphenol A.

[0036] In the process of the present invention, a fixed bed membrane reactor is innovatively used to replace the traditional fixed bed reactor, that is, the dehydration produced by the condensation reaction of phenol and acetone is removed in situ by using the reactor, thereby strengthening the catalytic-in situ dehydration effect. Compared with the existing industrial production of bisphenol A fixed bed reactor, the resin catalyst regeneration and replacement cycle is 3 months, and the resin catalyst life is 9 months. However, the resin catalyst does not need to be regenerated by using the membrane fixed bed reactor, and the catalyst life is extended to 27 to 36 months. At the same time, the equipment investment and operating costs caused by catalyst regeneration are reduced.

[0037] (2) Membrane materials for fixed bed membrane reactors

[0038] The present invention uses a molecular sieve with a CHA topological structure as an in-situ dehydration membrane for synthesizing bisphenol A. Its structure contains cage columns composed of alternating hexacyclic rings and CHA cages, and has a three-dimensional octahedral pore structure with an orifice diameter of 0.38nm×0.38nm (CHA molecular sieve). The pore size of CHA molecular sieve is larger than that of water molecules, but smaller than that of organic substances such as phenol, acetone and bisphenol A. It is an ideal membrane material for catalytic in-situ dehydration of bisphenol A. CHA molecular sieves are divided into two types: phosphorus aluminum type and silicon aluminum type. Among them, silicon aluminum type CHA molecular sieve has more suitable hydrophilicity and acid resistance. The higher the silicon aluminum ratio of silicon aluminum type CHA molecular sieve membrane, that is, the lower the aluminum content of the molecular sieve framework, the fewer cations that balance the negative charge of the framework, and the stronger the hydrophobicity of the membrane. Since the Al-O bond of the molecular sieve framework is easily hydrolyzed when there is more acid and water, the CHA molecular sieve with a high silicon aluminum ratio has better acid resistance and stability. Therefore, it is necessary to develop CHA molecular sieve membranes with a high silicon-aluminum ratio for bisphenol A membrane reactors to enhance the hydrophobicity, acid resistance and stability of the membranes.

[0039] Although the silicon-aluminum ratio of the silicon-aluminum type CHA molecular sieve can be regulated over a wide range, the silicon-aluminum ratio of the membrane layer of the CHA molecular sieve membrane prepared by using it as a seed is limited in the adjustable range. Compared with the CHA molecular sieve with a conventional silicon-aluminum ratio, the CHA molecular sieve with a high silicon-aluminum ratio (silicon-aluminum ratio is greater than or equal to 5) has a lower aluminum content, which leads to a more stable skeleton of the molecular sieve. The CHA molecular sieve with a low aluminum content has fewer acid sites on the surface and is not easy to cause acid-catalyzed side reactions caused by acid sites. Therefore, the use of CHA molecular sieves with a high silicon-aluminum ratio as a membrane material has a more stable dehydration performance. However, the preparation of CHA molecular sieve membranes with a high silicon-aluminum ratio usually requires the use of expensive organic templates or mineralizers that are harmful to the environment (such as mineralizers containing fluoride ions), resulting in the industrial application of CHA molecular sieve membranes with a high silicon-aluminum ratio being limited. At the same time, the existing high silicon-aluminum ratio CHA molecular sieves cannot be dehydrated in the bisphenol A reaction system because the Al content is still relatively high, that is, the silicon-aluminum ratio is between 5 and 10. Therefore, seeking a cheaper and faster method to prepare high silicon-aluminum ratio CHA molecular sieve is the key to solving the above problems.

[0040] To this end, the present invention proposes to use a relatively inexpensive molecular sieve with a *BEA topological structure, and innovatively use in-situ crystallization to prepare a CHA molecular sieve with a high silicon-aluminum ratio. In this process, the silicon-aluminum β molecular sieve with a *BEA topological structure is contacted with an acid solution for dealumination treatment to obtain a dealuminated β molecular sieve, which is then mixed with an alkaline solution and a template agent, and a high silicon-aluminum ratio CHA molecular sieve is obtained through crystallization, filtration, washing, and drying. That is, a molecular sieve with a *BEA topological structure is used as a raw material to prepare a CHA molecular sieve with a high silicon-aluminum ratio by in-situ crystallization. This method reduces the production cost of membrane materials while obtaining a membrane separation material with excellent dehydration performance.

[0041] The advantages and beneficial effects of the present invention are as follows:

[0042] (1) The present invention relates to a process for preparing bisphenol A by continuously strengthening the condensation reaction of acetone and phenol, which is characterized in that a bisphenol A reaction process is invented, which can separate the water produced by the condensation reaction of phenol and acetone from bisphenol A, phenol, acetone and other by-products, and after in-situ dehydration in a fixed bed membrane reactor, the water content in the product is reduced to below 0.5wt%.

[0043] (2) The present invention relates to a process for preparing bisphenol A by continuously intensifying the condensation reaction of acetone and phenol. The process is characterized in that a bisphenol A reaction process is invented, which uses a fixed bed membrane reactor for in-situ dehydration to reduce the energy consumption of the water separation, purification and recovery process of the bisphenol A product after dehydration. Compared with the conventional bisphenol A production process, the energy consumption of this method is reduced by 35-45%.

[0044] (3) The present invention relates to a process for preparing bisphenol A by continuously strengthening the condensation reaction of acetone and phenol. The process is characterized in that a bisphenol A reaction process is invented, wherein in-situ dehydration is performed in a fixed bed membrane reactor. The water content of the dehydrated product is reduced, and the influence on the resin catalyst for catalyzing the condensation reaction of acetone and phenol is minimized. A high selectivity for the formation of bisphenol A and a bisphenol A product yield are maintained, and the life of the catalyst is increased by 2 to 3 times. BRIEF DESCRIPTION OF THE DRAWINGS

[0045] Figure 1 The process flow diagram of the continuous enhanced condensation reaction of acetone and phenol to produce bisphenol A of the present invention is as follows

[0046] Figure 2 This is a simplified diagram of the structure of a fixed bed membrane reactor.

[0047] Figure 3 XRD spectrum of high silicon-aluminum ratio CHA molecular sieve sample S1 prepared in Example 1

[0048] Figure 4 XRD spectrum of high silicon-aluminum ratio CHA molecular sieve sample S2 prepared in Example 2

[0049] Figure 5 XRD spectrum of high silicon-aluminum ratio CHA molecular sieve sample S3 prepared in Example 3

[0050] Figure 6 XRD spectrum of high silicon-aluminum ratio CHA molecular sieve sample S4 prepared in Example 4

[0051] Figure 7 XRD spectrum of high silicon-aluminum ratio CHA molecular sieve sample S5 prepared in Example 5

[0052] Figure 8 XRD spectrum of high silicon-aluminum ratio CHA molecular sieve sample S6 prepared in Example 6 DETAILED DESCRIPTION

[0053] The present invention is further described in detail below with reference to the accompanying drawings and through specific embodiments. The following embodiments are merely illustrative and not restrictive, and the protection scope of the present invention cannot be limited thereto.

[0054] The following uses specific examples to illustrate the specific implementation process of the method of this application.

[0055] The invention discloses a process for preparing bisphenol A by continuously intensifying the condensation reaction of acetone and phenol, wherein bisphenol A is obtained by feeding phenol and acetone into a fixed-bed membrane reactor for condensation reaction and in-situ dehydration, concentration, solvent recovery, crystallization and separation.

[0056] The reaction process of the present invention for continuously strengthening the condensation reaction of acetone and phenol to prepare bisphenol A is shown in the attached Figure 1Phenol and acetone are added to a fixed bed membrane reactor (101) respectively, and condensed under the action of a resin catalyst to generate a bisphenol A product mixed liquid composed of bisphenol A, water and other by-products; at the same time, the bisphenol A product mixed liquid generated by the condensation is dehydrated in the fixed bed membrane reactor (101) by using a membrane material to allow water to pass through the fixed bed reactor to the outside of the fixed bed reactor, thereby achieving in-situ dehydration to obtain the bisphenol A product mixed liquid after in-situ dehydration; the bisphenol A product mixed liquid after in-situ dehydration is discharged from the fixed bed membrane reactor (101) The phenol and acetone are sent to a concentration tower (102) for concentration; the light components obtained at the top of the concentration tower (102) are recovered to obtain phenol and acetone, which are sent to a fixed bed membrane reactor (101) as raw materials, and continue to undergo condensation reaction under the action of a resin catalyst to produce bisphenol A; the concentrated reaction liquid obtained at the bottom of the concentration tower (102) is sent to a crystallization reactor (103) for crystallization with phenol to obtain a bisphenol A adduct and a crystallization mother liquor; and the bisphenol A adduct is then sent to a dephenolization reactor (104) to remove phenol to obtain a bisphenol A product. The reaction process flow of the continuous enhanced condensation reaction of acetone and phenol to produce bisphenol A of the present invention is different from the prior art in that a fixed bed membrane reactor with an in-situ dehydration function and a reaction separation and recovery process matched therewith are used.

[0057] The fixed bed membrane reactor (101) for continuously strengthening the condensation reaction of acetone and phenol to produce bisphenol A of the present invention is shown in the attached Figure 2 The fixed bed membrane reactor is divided into three parts. The interior of the reactor is used to fill the catalyst, and the reactants contact with the catalyst in this area to react and flow to the reactor outlet; the middle part of the reactor is a membrane material, which is used to selectively permeate the products generated inside the reactor into the vacuum system connected to the outside; the outside of the reactor is an area where water separated by the membrane material flows and flows to the liquid collection device. The fixed bed membrane reactor (101) is filled with a resin catalyst to catalyze the condensation reaction of acetone and phenol; the middle part of the fixed bed membrane reactor is a molecular sieve membrane with a CHA topological structure to remove the water generated by the reaction.

[0058] According to the above-mentioned Figure 1 , 2 The process and equipment, the specific operation examples are as follows:

[0059] Example 1

[0060] A fixed bed membrane reactor (101) is filled with a gel-type acidic ion exchange resin, the crosslinking degree of the resin is 1.0%, the particle size range is 0.4 nm, and the water content of the resin is 20% by weight of the resin; phenol and acetone are reacted under the catalytic action of the acidic ion exchange resin at a reaction temperature of 45°C and a reaction pressure of 0.1 MPaA, and the hourly feed volume of phenol and acetone is 0.1 times the volume of the resin catalyst, to obtain a mixed solution containing a bisphenol A product. The mixed liquid containing bisphenol A product is dehydrated in situ in a fixed bed membrane reactor (101), and the vacuum degree on the permeate side of the fixed bed membrane reactor is controlled at 0.1 mbar; the mixed liquid of the product at the outlet of the fixed bed membrane reactor (101) is sent to a concentration tower (102) for concentration; the light components obtained at the top of the concentration tower (102) are recovered to obtain phenol and acetone, and sent to the fixed bed membrane reactor (101); the concentrated reaction liquid obtained at the bottom of the concentration tower (102) is sent to a crystallization reactor (103) to crystallize with phenol to obtain a bisphenol A adduct and a crystallization mother liquor; the bisphenol A adduct is sent to a dephenolization reactor (104) to remove phenol to obtain a bisphenol A product.

[0061] The membrane carrier of the fixed bed membrane reactor (101) in this embodiment is α-Al 2 O 3 The dehydration membrane is a CHA molecular sieve with a high silicon-aluminum ratio, and its preparation method is as follows: (1) the silicon-aluminum β molecular sieve is dealuminated: 20g of β molecular sieve with a silicon-aluminum ratio of 500 is mixed with 200ml of 13 mol / l nitric acid solution, the ratio of the acid solution liquid volume (ml) to the β molecular sieve solid mass (g) is 10:1 (ml / g), stirred at 120°C for 12 hours, dealuminated, and then filtered, washed, and dried to obtain the dealuminated β molecular sieve D1; (2) the dealuminated β molecular sieve Z is crystallized to prepare CHA molecular sieve: 6.66g of dealuminated β molecular sieve and 100ml of 0.4 mol / l NaOH solution are mixed with 100ml A mixture of 0.4 mol / L tetrapropylammonium hydroxide solution is mixed to obtain a crystallization directing agent, the ratio of the crystallization directing agent to the dealuminated β molecular sieve D1 solid mass (gram) is 1:5 (ml / g), and the mixture is stirred at 120°C for 120 hours for crystallization treatment, and then filtered, washed and dried to obtain a solid sample S1.

[0062] The obtained product was subjected to XRD analysis, and the XRD spectrum was as follows Figure 3As shown, it shows that the product is a molecular sieve with a CHA topological structure; the obtained product is subjected to ICP analysis, and the results are shown in Table 1, indicating that the silicon-aluminum ratio of the product is 27. In summary, it can be seen that the above method is used to prepare a high silicon-aluminum ratio CHA molecular sieve. The obtained high silicon-aluminum ratio CHA molecular sieve is used as a fixed bed membrane reactor for bisphenol A production. The water content of the obtained product is shown in Table 1, which is less than 0.5wt%, achieving a good dehydration effect; the energy consumption of the reaction process is compared, and the bisphenol A production process without using a high silicon-aluminum ratio CHA molecular sieve membrane is used as a reference object to compare the energy consumption reduction of the bisphenol A production process using a high silicon-aluminum ratio CHA molecular sieve membrane. The results are listed in Table 1, which significantly reduces energy consumption; when the bisphenol A production process without using a high silicon-aluminum ratio CHA molecular sieve membrane, the life of the resin catalyst is 6 to 8 months, and when the bisphenol A production process using a high silicon-aluminum ratio CHA molecular sieve membrane is used, the life of the resin catalyst is significantly improved, and the results are listed in Table 1.

[0063] Example 2

[0064] A fixed bed membrane reactor (101) is filled with a gel-type acidic ion exchange resin, the crosslinking degree of the resin is 6.0%, the particle size range is 2.0 nm, and the water content of the resin is 40% by weight of the resin; phenol and acetone are reacted under the catalytic action of the acidic ion exchange resin at a reaction temperature of 70°C and a reaction pressure of 0.5 MPaA, and the hourly feed volume of phenol and acetone is 2.0 times the volume of the resin catalyst, to obtain a mixed solution containing a bisphenol A product. The mixed liquid containing bisphenol A product is dehydrated in situ in a fixed bed membrane reactor (101), and the vacuum degree on the permeate side of the fixed bed membrane reactor is controlled at 0.5 mbar; the mixed liquid of the product at the outlet of the fixed bed membrane reactor (101) is sent to a concentration tower (102) for concentration; the light components obtained at the top of the concentration tower (102) are recovered to obtain phenol and acetone, and sent to the fixed bed membrane reactor (101); the concentrated reaction liquid obtained at the bottom of the concentration tower (102) is sent to a crystallization reactor (103) to crystallize with phenol to obtain a bisphenol A adduct and a crystallization mother liquor; the bisphenol A adduct is sent to a dephenolization reactor (104) to remove phenol to obtain a bisphenol A product.

[0065] The membrane carrier of the fixed bed membrane reactor (101) in this embodiment is α-Al 2 O 3The dehydration membrane is a CHA molecular sieve with a high silicon-aluminum ratio, and its preparation method is as follows: (1) the silicon-aluminum β molecular sieve is dealuminated: 20g of β molecular sieve with a silicon-aluminum ratio of 500 is mixed with 200ml of 13 mol / l nitric acid solution, the ratio of the acid solution liquid volume (ml) to the β molecular sieve solid mass (g) is 20:1 (ml / g), stirred at 120°C for 12 hours, dealuminated, and then filtered, washed, and dried to obtain the dealuminated β molecular sieve D2; (2) the dealuminated β molecular sieve Z is crystallized to prepare CHA molecular sieve: 6.66g of dealuminated β molecular sieve and 100ml of 0.4 mol / l NaOH solution are mixed with 100ml A mixture of 0.4 mol / L tetrapropylammonium hydroxide solution is mixed to obtain a crystallization directing agent, the ratio of the crystallization directing agent to the dealuminated β molecular sieve D2 solid mass (gram) is 1:200 (ml / g), and the mixture is stirred at 180°C for 1 hour for crystallization treatment, and then filtered, washed and dried to obtain a solid sample S2.

[0066] The obtained product was subjected to XRD analysis, and the XRD spectrum was as follows Figure 4 As shown, it shows that the product is a molecular sieve with a CHA topological structure; the obtained product is subjected to ICP analysis, and the results are shown in Table 1, indicating that the silicon-aluminum ratio of the product is 55. In summary, it can be seen that the above method is used to prepare a high silicon-aluminum ratio CHA molecular sieve. The obtained high silicon-aluminum ratio CHA molecular sieve is used as a fixed bed membrane reactor for bisphenol A production. The water content of the obtained product is shown in Table 1, which is less than 0.5wt%, achieving a good dehydration effect; the energy consumption of the reaction process is compared, and the bisphenol A production process without using a high silicon-aluminum ratio CHA molecular sieve membrane is used as a reference object. The energy consumption reduction of the bisphenol A production process using a high silicon-aluminum ratio CHA molecular sieve membrane is compared. The results are listed in Table 1, which significantly reduces energy consumption; when the bisphenol A production process without using a high silicon-aluminum ratio CHA molecular sieve membrane, the life of the resin catalyst is 6 to 8 months, and when the bisphenol A production process using a high silicon-aluminum ratio CHA molecular sieve membrane is used, the life of the resin catalyst is significantly improved, and the results are listed in Table 1.

[0067] Example 3

[0068] A fixed bed membrane reactor (101) is filled with a gel-type acidic ion exchange resin, the crosslinking degree of the resin is 10.0%, the particle size range is 4.0 nm, and the water content of the resin is 60% by weight of the resin; phenol and acetone are reacted under the catalytic action of the acidic ion exchange resin at a reaction temperature of 80°C and a reaction pressure of 0.1 MPaA, and the hourly feed volume of phenol and acetone is 4.0 times the volume of the resin catalyst, to obtain a mixed solution containing a bisphenol A product. The mixed liquid containing bisphenol A product is dehydrated in situ in a fixed bed membrane reactor (101), and the vacuum degree on the permeate side of the fixed bed membrane reactor is controlled at 1.0 mbar; the mixed liquid of the product at the outlet of the fixed bed membrane reactor (101) is sent to a concentration tower (102) for concentration; the light components obtained at the top of the concentration tower (102) are recovered to obtain phenol and acetone, and sent to the fixed bed membrane reactor (101); the concentrated reaction liquid obtained at the bottom of the concentration tower (102) is sent to a crystallization reactor (103) to crystallize with phenol to obtain a bisphenol A adduct and a crystallization mother liquor; the bisphenol A adduct is sent to a dephenolization reactor (104) to remove phenol to obtain a bisphenol A product.

[0069] In this embodiment, the membrane carrier of the fixed bed membrane reactor (101) is a hollow fiber, and the dehydration membrane is a CHA molecular sieve with a high silicon-aluminum ratio. The preparation method thereof is as follows: (1) subjecting the silicon-aluminum β molecular sieve to dealumination treatment: 20 g of β molecular sieve with a silicon-aluminum ratio of 20 is mixed with 200 ml of a 10 mol / l nitric acid solution, wherein the ratio of the volume of the acidic solution (ml) to the solid mass of the β molecular sieve (g) is 5:1 (ml / g), and the mixture is stirred at 120° C. for 12 hours to subject the mixture to dealumination treatment. The dealumination β molecular sieve D3 is then obtained by filtering, washing and drying; (2) subjecting the dealumination β molecular sieve Z to crystallization to prepare the CHA molecular sieve: 6.66 g of the dealumination β molecular sieve and 100 ml of a 0.4 mol / l NaOH solution are mixed with 100 ml of a 10 mol / l nitric acid solution. A mixture of 0.4 mol / L tetrapropylammonium hydroxide solution is mixed to obtain a crystallization directing agent, the ratio of the crystallization directing agent to the dealuminated β molecular sieve D3 solid mass (gram) is 1:100 (ml / g), and the mixture is stirred at 140°C for 48 hours for crystallization treatment, and then filtered, washed and dried to obtain a solid sample S3.

[0070] The obtained product was subjected to XRD analysis, and the XRD spectrum was as follows Figure 5As shown, it shows that the product is a molecular sieve with a CHA topological structure; the obtained product is subjected to ICP analysis, and the results are shown in Table 1, indicating that the silicon-aluminum ratio of the product is 180. In summary, it can be seen that the above method is used to prepare a high silicon-aluminum ratio CHA molecular sieve. The obtained high silicon-aluminum ratio CHA molecular sieve is used as a fixed bed membrane reactor for bisphenol A production. The water content of the obtained product is shown in Table 1, which is less than 0.5wt%, achieving a good dehydration effect; the energy consumption of the reaction process is compared, and the bisphenol A production process without using a high silicon-aluminum ratio CHA molecular sieve membrane is used as a reference object to compare the energy consumption reduction of the bisphenol A production process using a high silicon-aluminum ratio CHA molecular sieve membrane. The results are listed in Table 1, which significantly reduces energy consumption; when the bisphenol A production process without using a high silicon-aluminum ratio CHA molecular sieve membrane, the life of the resin catalyst is 6 to 8 months, and when the bisphenol A production process using a high silicon-aluminum ratio CHA molecular sieve membrane is used, the life of the resin catalyst is significantly improved, and the results are listed in Table 1.

[0071] Example 4

[0072] A fixed bed membrane reactor (101) is filled with a macroporous acidic ion exchange resin, the crosslinking degree of the resin is 10.0%, the particle size range is 5.0 nm, and the water content of the resin is 90% by weight of the resin; phenol and acetone are reacted under the catalytic action of the acidic ion exchange resin at a reaction temperature of 80°C and a reaction pressure of 0.3 MPaA, and the hourly feed volume of phenol and acetone is 4.0 times the volume of the resin catalyst, to obtain a mixed solution containing a bisphenol A product. The mixed liquid containing bisphenol A product is dehydrated in situ in a fixed bed membrane reactor (101), and the vacuum degree on the permeate side of the fixed bed membrane reactor is controlled at 3.0 mbar; the mixed liquid of the product at the outlet of the fixed bed membrane reactor (101) is sent to a concentration tower (102) for concentration; the light components obtained at the top of the concentration tower (102) are recovered to obtain phenol and acetone, and sent to the fixed bed membrane reactor (101); the concentrated reaction liquid obtained at the bottom of the concentration tower (102) is sent to a crystallization reactor (103) to crystallize with phenol to obtain a bisphenol A adduct and a crystallization mother liquor; the bisphenol A adduct is sent to a dephenolization reactor (104) to remove phenol to obtain a bisphenol A product.

[0073] In this embodiment, the membrane carrier of the fixed bed membrane reactor (101) is mullite, and the dehydration membrane is a CHA molecular sieve with a high silicon-aluminum ratio. The preparation method thereof is as follows: (1) subjecting the silicon-aluminum β molecular sieve to dealumination treatment: 20 g of β molecular sieve with a silicon-aluminum ratio of 50 is mixed with 200 ml of 13 mol / l nitric acid solution, the ratio of the acid solution liquid volume (ml) to the β molecular sieve solid mass (g) being 10:1 (ml / g), stirring at 160° C. for 12 hours, subjecting the mixture to dealumination treatment, and then filtering, washing, and drying to obtain dealumination β molecular sieve D4; (2) crystallizing the dealumination β molecular sieve Z to prepare CHA molecular sieve: 6.66 g of dealumination β molecular sieve and 100 ml of 0.4 mol / l NaOH solution are mixed with 100 ml of 100 ml of 100 ml of 0.4 mol / l NaOH solution; A mixture of 0.4 mol / L tetrapropylammonium hydroxide solution is mixed to obtain a crystallization directing agent, the ratio of the crystallization directing agent to the dealuminated β molecular sieve D4 solid mass (gram) is 1:150 (ml / g), and the mixture is stirred at 160°C for 120 hours for crystallization treatment, and then filtered, washed and dried to obtain a solid sample S4.

[0074] The obtained product was subjected to XRD analysis, and the XRD spectrum was as follows Figure 6 As shown, it shows that the product is a molecular sieve with a CHA topological structure; the obtained product is subjected to ICP analysis, and the results are shown in Table 1, indicating that the silicon-aluminum ratio of the product is 330. In summary, it can be seen that the above method is used to prepare a high silicon-aluminum ratio CHA molecular sieve. The obtained high silicon-aluminum ratio CHA molecular sieve is used as a fixed bed membrane reactor for bisphenol A production. The water content of the obtained product is shown in Table 1, which is less than 0.5wt%, achieving a good dehydration effect; the energy consumption of the reaction process is compared, and the bisphenol A production process without using a high silicon-aluminum ratio CHA molecular sieve membrane is used as a reference object to compare the energy consumption reduction of the bisphenol A production process using a high silicon-aluminum ratio CHA molecular sieve membrane. The results are listed in Table 1, which significantly reduces energy consumption; when the bisphenol A production process without using a high silicon-aluminum ratio CHA molecular sieve membrane, the life of the resin catalyst is 6 to 8 months, and when the bisphenol A production process using a high silicon-aluminum ratio CHA molecular sieve membrane is used, the life of the resin catalyst is significantly improved, and the results are listed in Table 1.

[0075] Example 5

[0076] A fixed bed membrane reactor (101) is filled with a gel-type acidic ion exchange resin, the crosslinking degree of the resin is 20.0%, the particle size range is 2.0 nm, and the water content of the resin is 50% by weight of the resin; phenol and acetone are reacted under the catalytic action of the acidic ion exchange resin at a reaction temperature of 75°C and a reaction pressure of 0.1 MPaA, and the hourly feed volume of phenol and acetone is 10 times the volume of the resin catalyst, to obtain a mixed solution containing a bisphenol A product. The mixed liquid containing bisphenol A product is dehydrated in situ in a fixed bed membrane reactor (101), and the vacuum degree on the permeate side of the fixed bed membrane reactor is controlled at 2.0 mbar; the mixed liquid of the product at the outlet of the fixed bed membrane reactor (101) is sent to a concentration tower (102) for concentration; the light components obtained at the top of the concentration tower (102) are recovered to obtain phenol and acetone, and sent to the fixed bed membrane reactor (101); the concentrated reaction liquid obtained at the bottom of the concentration tower (102) is sent to a crystallization reactor (103) to crystallize with phenol to obtain a bisphenol A adduct and a crystallization mother liquor; the bisphenol A adduct is sent to a dephenolization reactor (104) to remove phenol to obtain a bisphenol A product.

[0077] In this embodiment, the membrane carrier of the fixed bed membrane reactor (101) is stainless steel, and the dehydration membrane is a CHA molecular sieve with a high silicon-aluminum ratio. The preparation method thereof is as follows: (1) subjecting the silicon-aluminum β molecular sieve to dealumination treatment: 20 g of β molecular sieve with a silicon-aluminum ratio of 20 is mixed with 200 ml of a 10 mol / l nitric acid solution, wherein the ratio of the acid solution liquid volume (ml) to the β molecular sieve solid mass (g) is 30:1 (ml / g), and the mixture is stirred at 120° C. for 12 hours to subject the mixture to dealumination treatment, and then filtered, washed, and dried to obtain the dealuminated β molecular sieve D5; (2) subjecting the dealuminated β molecular sieve Z to crystallization to prepare the CHA molecular sieve: 6.66 g of the dealuminated β molecular sieve and 100 ml of a 0.4 mol / l NaOH solution are mixed with 100 ml of a 10 mol / l nitric acid solution. A mixture of 0.4 mol / L tetrapropylammonium hydroxide solution is mixed to obtain a crystallization directing agent, the ratio of the crystallization directing agent to the dealuminated β molecular sieve D5 solid mass (gram) is 1:50 (ml / g), and the mixture is stirred at 180°C for 48 hours for crystallization treatment, and then filtered, washed and dried to obtain a solid sample S5.

[0078] The obtained product was subjected to XRD analysis, and the XRD spectrum was as follows Figure 7As shown, it shows that the product is a molecular sieve with a CHA topological structure; the obtained product is subjected to ICP analysis, and the results are shown in Table 1, indicating that the silicon-aluminum ratio of the product is 500. In summary, it can be seen that the above method is used to prepare a high silicon-aluminum ratio CHA molecular sieve. The obtained high silicon-aluminum ratio CHA molecular sieve is used as a fixed bed membrane reactor for bisphenol A production. The water content of the obtained product is shown in Table 1, which is less than 0.5wt%, achieving a good dehydration effect; the energy consumption of the reaction process is compared, and the bisphenol A production process without using a high silicon-aluminum ratio CHA molecular sieve membrane is used as a reference object to compare the energy consumption reduction of the bisphenol A production process using a high silicon-aluminum ratio CHA molecular sieve membrane. The results are listed in Table 1, which significantly reduces energy consumption; when the bisphenol A production process without using a high silicon-aluminum ratio CHA molecular sieve membrane, the life of the resin catalyst is 6 to 8 months, and when the bisphenol A production process using a high silicon-aluminum ratio CHA molecular sieve membrane is used, the life of the resin catalyst is significantly improved, and the results are listed in Table 1.

[0079] Example 6

[0080] A fixed bed membrane reactor (101) is filled with a gel-type acidic ion exchange resin, the crosslinking degree of the resin is 10.0%, the particle size range is 4.0 nm, and the water content of the resin is 60% by weight of the resin; phenol and acetone are reacted under the catalytic action of the acidic ion exchange resin at a reaction temperature of 95° C. and a reaction pressure of 0.1 MPaA, and the hourly feed volume of phenol and acetone is 6.0 times the volume of the resin catalyst, to obtain a mixed solution containing a bisphenol A product. The mixed liquid containing bisphenol A product is dehydrated in situ in a fixed bed membrane reactor (101), and the vacuum degree on the permeate side of the fixed bed membrane reactor is controlled at 1.5 mbar; the mixed liquid of the product at the outlet of the fixed bed membrane reactor (101) is sent to a concentration tower (102) for concentration; the light components obtained at the top of the concentration tower (102) are recovered to obtain phenol and acetone, and sent to the fixed bed membrane reactor (101); the concentrated reaction liquid obtained at the bottom of the concentration tower (102) is sent to a crystallization reactor (103) to crystallize with phenol to obtain a bisphenol A adduct and a crystallization mother liquor; the bisphenol A adduct is sent to a dephenolization reactor (104) to remove phenol to obtain a bisphenol A product.

[0081] The membrane carrier of the fixed bed membrane reactor (101) in this embodiment is α-Al 2 O 3The dehydration membrane is a CHA molecular sieve with a high silicon-aluminum ratio, and its preparation method is as follows: (1) the silicon-aluminum β molecular sieve is dealuminated: 20g of β molecular sieve with a silicon-aluminum ratio of 80 is mixed with 200ml of 13 mol / l nitric acid solution, the ratio of the acid solution liquid volume (ml) to the β molecular sieve solid mass (g) is 10:1 (ml / g), stirred at 120°C for 24 hours, dealuminated, and then filtered, washed, and dried to obtain dealuminated β molecular sieve D6; (2) the dealuminated β molecular sieve Z is crystallized to prepare CHA molecular sieve: 6.66g of dealuminated β molecular sieve and 100ml of 0.4 mol / l NaOH solution are mixed with 100ml A mixture of 0.4 mol / L tetrapropylammonium hydroxide solution is mixed to obtain a crystallization directing agent, the ratio of the crystallization directing agent to the dealuminated β molecular sieve D6 solid mass (gram) is 1:80 (ml / g), and the mixture is stirred at 120°C for 48 hours for crystallization treatment, and then filtered, washed and dried to obtain a solid sample S6.

[0082] The obtained product was subjected to XRD analysis, and the XRD spectrum was as follows Figure 8 As shown, it shows that the product is a molecular sieve with a CHA topological structure; the obtained product is subjected to ICP analysis, and the results are shown in Table 1, indicating that the silicon-aluminum ratio of the product is 430. In summary, it can be seen that the above method is used to prepare a high silicon-aluminum ratio CHA molecular sieve. The obtained high silicon-aluminum ratio CHA molecular sieve is used as a fixed bed membrane reactor for bisphenol A production. The water content of the obtained product is shown in Table 1, which is less than 0.5wt%, achieving a good dehydration effect; the energy consumption of the reaction process is compared, and the bisphenol A production process without using a high silicon-aluminum ratio CHA molecular sieve membrane is used as a reference object to compare the energy consumption reduction of the bisphenol A production process using a high silicon-aluminum ratio CHA molecular sieve membrane. The results are listed in Table 1, which significantly reduces energy consumption; when the bisphenol A production process without using a high silicon-aluminum ratio CHA molecular sieve membrane, the life of the resin catalyst is 6 to 8 months, and when the bisphenol A production process using a high silicon-aluminum ratio CHA molecular sieve membrane is used, the life of the resin catalyst is significantly improved, and the results are listed in Table 1.

[0083] Table 1

[0084]

[0085]

[0086] The preferred embodiments of the present disclosure are described in detail above in conjunction with the accompanying drawings; however, the present disclosure is not limited to the specific details in the above embodiments. Within the technical concept of the present disclosure, a variety of simple modifications can be made to the technical solution of the present disclosure, and these simple modifications all fall within the protection scope of the present disclosure.

[0087] It should also be noted that the various specific technical features described in the above specific embodiments can be combined in any suitable manner without contradiction. In order to avoid unnecessary repetition, the present disclosure will not further describe various possible combinations.

[0088] In addition, various embodiments of the present disclosure may be arbitrarily combined, and as long as they do not violate the concept of the present disclosure, they should also be regarded as the contents disclosed by the present disclosure.

Claims

1. A process for preparing bisphenol A by continuously strengthening the condensation reaction of acetone and phenol, characterized in that: The steps include: 1) Phenol and acetone are added to a fixed bed membrane reactor respectively, and condensed under the action of a resin catalyst to generate a bisphenol A product mixed liquid consisting of bisphenol A, water and other by-products; 2) In a fixed bed membrane reactor, the bisphenol A product mixed liquid generated by the condensation is subjected to in-situ dehydration by using a CHA molecular sieve membrane material with a high silicon-aluminum ratio to allow water to pass through the fixed bed reactor to the outside of the fixed bed reactor, thereby obtaining an in-situ dehydrated bisphenol A product mixed liquid; 3) sending the bisphenol A product mixed liquid after in-situ dehydration at the outlet of the fixed bed membrane reactor to a concentration tower for concentration; 4) The light components obtained from the top of the concentration tower are recovered to obtain phenol and acetone, which are sent to a fixed bed membrane reactor as raw materials to continue to undergo condensation reaction under the action of a resin catalyst to produce bisphenol A; 5) The concentrated reaction liquid obtained from the reactor of the concentration tower is sent to a crystallization reactor to be crystallized with phenol to obtain a bisphenol A adduct and a crystallization mother liquor, and then the bisphenol A adduct is sent to a dephenolization reactor to remove phenol to obtain a bisphenol A product.

2. The process for preparing bisphenol A by continuously strengthening the condensation reaction of acetone and phenol as claimed in claim 1, characterized in that: The catalyst is an acidic ion exchange resin, the catalyst is an acidic ion exchange resin, the crosslinking degree of the acidic ion exchange resin is 1.0% to 20%, the particle size range is 0.4nm to 5.0nm, and the water content of the acidic ion exchange resin is 20% to 90% by weight of the acidic ion exchange resin.

3. The process for preparing bisphenol A by continuously strengthening the condensation reaction of acetone and phenol as claimed in claim 1, characterized in that: The condensation reaction temperature of phenol and acetone in the fixed bed membrane reactor is 45-95°C, and the reaction pressure is 0.1-0.5MpaA.

4. The process for preparing bisphenol A by continuously strengthening the condensation reaction of acetone and phenol as claimed in claim 1, characterized in that: The hourly feed volume of phenol and acetone is 0.1 to 10 times the volume of the resin catalyst.

5. The process for preparing bisphenol A by continuously strengthening the condensation reaction of acetone and phenol as claimed in claim 1, characterized in that: The outside of the fixed bed membrane reactor is connected to a vacuum system, and the vacuum system controls the vacuum degree of the permeate side of the fixed bed membrane reactor to 0.1-3 mbar.

6. The process for preparing bisphenol A by continuously strengthening the condensation reaction of acetone and phenol as claimed in claim 1, characterized in that: The preparation method of the CHA molecular sieve membrane material with a high silicon-aluminum ratio used in a fixed-bed membrane reactor is as follows: first, a molecular sieve with a *BEA topological structure is dealuminated to obtain a *BEA molecular sieve after dealumination, and the dealuminated *BEA molecular sieve is coated on the surface of one of α-Al2O3, hollow fiber, mullite, and stainless steel; then, under the action of a crystallization directing agent, the CHA molecular sieve membrane material with a high silicon-aluminum ratio is crystallized to obtain.

7. The process for preparing bisphenol A by continuously strengthening the condensation reaction of acetone and phenol as claimed in claim 6, characterized in that: The crystal-transforming directing agent is one or a combination of sodium oxide, potassium hydroxide, tetramethylammonium hydroxide, tetraethylammonium hydroxide, tetrapropylammonium hydroxide, tetrabutylammonium hydroxide, and ammonia water; the mass ratio of the crystal-transforming directing agent to the dealuminated *BEA molecular sieve is 1:5-200.

8. The process for preparing bisphenol A by continuously strengthening the condensation reaction of acetone and phenol as claimed in claim 6, characterized in that: The crystallization conditions are 120 to 180° C. for 1 to 120 hours.

9. The process for preparing bisphenol A by continuously strengthening the condensation reaction of acetone and phenol as claimed in claim 1, characterized in that: The fixed bed membrane reactor is divided into three parts. The inside of the reactor is used to fill the catalyst, and the reactants contact the catalyst in this area to react and flow to the reactor outlet; the middle part of the reactor is the membrane material, which is used to selectively permeate the products produced inside the reactor to the vacuum system connected to the outside; the outside of the reactor is the area where water separated by the membrane material flows and flows to the liquid collection device.

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