Method for reducing by-products in a reaction system of bisphenol A

Abstract

An object of the present invention is to provide a method for reducing by-products in a reaction system of bisphenol A. 【Solution means】 A process of sending the mother liquor generated after reacting, concentrating, crystallizing, and separating phenol and acetone to a mother liquor recovery system, a process of subjecting the mother liquor obtained by the mother liquor recovery system to an isomerization reaction by contacting it with a sulfonic acid group-containing metal organic framework catalyst, and a process of sending the product obtained by the isomerization reaction to the mother liquor recovery system and obtaining bisphenol A through crystallization and dephenolization. An isomerization reaction catalyst for by-products of bisphenol A is invented, the amount of sulfonic acid and the pore diameter of the catalyst can be adjusted, the conversion rate of by-products of bisphenol A in the catalytic reaction is high and can reach 28% to 55%, the selectivity of bisphenol A is also high and can reach 80% to 90%, and the by-products of bisphenol A are efficiently converted into bisphenol A is realized.

Description

Technical Field

[0001] The present invention relates to a method for reducing by-products in the reaction system of bisphenol A, and particularly to a method and a catalyst for producing bisphenol A by catalyzing the isomerization of by-products 2,4-BPA, triphenol, and chroman in a catalytic bisphenol A reaction system, and also relates to a method for reducing by-products in the reaction system of bisphenol A.

Background Art

[0002] Bisphenol A (BPA), chemical name 2,2-bis(4-hydroxyphenyl)propane, is a widely used organic chemical raw material produced by condensing phenol and acetone under the action of a catalyst, and is mainly used in the production of polymer materials such as polycarbonate and epoxy resin.

[0003] In the bisphenol A reaction, 2,4-bisphenol A (abbreviated as 2,4-BPA) is produced as a by-product, and p-isopropenylphenol produced by condensing phenol and acetone continues to react with the main product bisphenol A to produce 4-(2,2,4-trimethylchroman-4-yl)phenol (abbreviated as triphenol). In addition, the raw material phenol contains a small amount of mesityl acetone and mesityl acetone produced by acetone itself under acidic catalyst conditions, and can react with phenol by condensation to produce 2-2-4-trimethyl-4-(4'-hydroxyphenyl)-chroman, 1,1,3-trimethyl-1-(4'-hydroxyphenyl)indan-6-ol (abbreviated as chroman). The by-products in the above-mentioned bisphenol A reaction affect the purity and color of the product bisphenol A, and affect the quality of the product and its downstream use. Therefore, the treatment of the crystallization mother liquor is an important step to ensure the quality of the final product and the raw materials.

[0004] To solve the above problems, an isomerization reaction is performed on by-products of bisphenol A to obtain more product bisphenol A. In Patent Document 1, a method for producing bisphenol A from phenol and acetone through a catalytic condensation reaction in the presence of a sulfonated ion exchange resin is disclosed. The concentrated crystallization liquid stream of bisphenol A is targeted and isomerized in the presence of a macroporous sulfonated ion exchange catalyst. In Patent Document 2, after the mixed solution after the reaction of phenol and acetone is concentrated, crystallized, and solid-liquid separated, a part of the obtained mother liquor is subjected to an isomerization treatment, and then crystallized and solid-liquid separated to obtain bisphenol A. A method for producing bisphenol A is disclosed. In Patent Document 3, a product obtained by producing bisphenol from a condensation reaction of a ketone and phenol is subjected to an isomerization reaction with an ion exchange resin having a sulfonic acid group under aqueous conditions, and separated to obtain bisphenol. An isomerization method is disclosed.

[0005] Currently, the industrially used catalyst for catalyzing the isomerization reaction of 2,4-BPA, a by-product of bisphenol A, is an acidic ion exchange resin. However, its catalyst selectivity is relatively low, its catalyst stability is not high, and deactivation due to pore blockage and coke accumulation is likely to occur. This is mainly because the molecular size of the by-products of bisphenol A is large, so a larger reaction space is required. The resin is limited by the degree of cross-linking and swelling, and the pore size adjustment characteristics are poor, which is disadvantageous for the mass transfer and diffusion of by-products during the catalytic reaction. Moreover, the sulfonic acid group and thiol group that exhibit isomerization catalyst activity in the isomerization reaction are likely to flow out of the resin, reducing the catalyst performance and corroding the equipment, and affecting the subsequent separation and product quality.

[0006] In short, in the current reaction process for synthesizing bisphenol A using a resin catalyst, no appropriate method scheme for isomerizing and converting by-products in the reaction to obtain bisphenol A has been considered. In particular, regarding the crystallization mother liquor after the reaction, maximum recovery and concentration of by-products have not been considered, and there is a lack of an appropriate operation scheme for isomerization treatment of multi-component and high-molecular by-products. Therefore, it is necessary to develop a process for efficiently reducing by-products in the bisphenol A reaction system and obtain a catalyst suitable for the by-product isomerization reaction in the bisphenol A reaction system using a manufacturing method capable of adjusting the pore structure and controlling the acidic sites.

[0007] Therefore, paying attention to problems such as poor concentration effect of by-products and low isomerization reaction activity in the process of catalyzing the isomerization treatment of by-products of bisphenol A, the present invention develops a new isomerization treatment method and a compatible and appropriate isomerization catalyst. The main novelty is to react, concentrate, crystallize, and separate phenol and acetone, then collect the bisphenol A-containing by-products generated, obtain a mother liquor rich in by-products of bisphenol A, and propose an isomerization treatment method of sending it to an isomerization reactor. It can adjust the sulfonic acid content and thiol content, use a sulfonic acid group-containing metal-organic framework catalyst suitable for the reaction of bisphenol A high-molecular by-products to catalyze the isomerization of by-products of bisphenol A, and obtain a high conversion rate of by-products of bisphenol A and a bisphenol A yield.

Prior Art Documents

Patent Documents

[0008]

Patent Document 1

Patent Document 2

Patent Document 3

Summary of the Invention

Problems to be Solved by the Invention

[0009] The object of the present invention is to send the mother liquor generated after reacting, concentrating, crystallizing, and separating phenol and acetone to a partial decomposition rearrangement reactor and an isomerization reactor respectively, then subject the mother liquor to an isomerization reaction by contacting it with a metal-organic framework catalyst containing a sulfonic acid group, and crystallize and separate the obtained product to obtain bisphenol A, thereby providing a method for reducing by-products in the reaction system of bisphenol A. By using this method to treat the by-products in the reaction system of bisphenol A, the by-products of bisphenol A can be efficiently converted into bisphenol A, the conversion rate of the by-products of bisphenol A is high, and the yield of the obtained product bisphenol A is also high.

[0010] The isomerization reaction formula is as follows.

[0011] [Chemical formula] [Means for Solving the Problems]

[0012] To achieve the above object, the technical means adopted by the present invention are as follows.

[0013] A method for reducing by-products in the reaction system of bisphenol A, wherein the mother liquor generated after reacting, concentrating, crystallizing, and separating phenol and acetone is partially sent to a decomposition rearrangement reactor and an isomerization reactor respectively, then the mother liquor is subjected to an isomerization reaction by contacting it with a metal-organic framework catalyst containing a sulfonic acid group, and the obtained product is crystallized and separated to obtain bisphenol A.

[0014] A method for reducing by-products in the reaction system of bisphenol A, (a) A step of sending the mother liquor generated after reacting, concentrating, crystallizing, and separating phenol and acetone to a mother liquor recovery system; (b) A step of subjecting the mother liquor obtained by the mother liquor recovery system to an isomerization reaction by contacting it with a metal-organic framework catalyst containing a sulfonic acid group; and (c) The product obtained by the isomerization reaction is sent to a mother liquor recovery system, and bisphenol A is obtained through crystallization and dephenolization. The above method, characterized by including this.

[0015] In the step (a): Phenol and acetone are synthesized in a bisphenol A reactor (101) to obtain bisphenol A. The reaction solution at the outlet of the bisphenol A reactor (101) is sent to a concentration tower (102) for concentration. The light components obtained at the top of the concentration tower (102) as are recovered by a solvent recovery system, a light component The obtained phenol and acetone are sent to the bisphenol A reactor (101). The concentrated reaction solution obtained from 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 the crystallization mother liquor of the reactor. The bisphenol A adduct is sent to a dephenolization reactor (104) to remove phenol to obtain the product bisphenol A. The dephenolization is sent to a mother liquor recovery system (106). The crystallization mother liquor of the reactor is sent to the mother liquor recovery system (106) to recover the mother liquor. The phenol recovered by the mother liquor recovery system (106) is sent to the bisphenol A reactor (101), and the bisphenol A adduct recovered by the mother liquor recovery system (106) is sent to the crystallization reactor (103).

[0016] In the step (b): After the mother liquor recovery system (106) recovers phenol and the bisphenol A adduct, a part of the crystallization mother liquor of the recovery system obtained is sent to an isomerization reactor (107) storing a sulfonic acid group-containing metal organic framework catalyst to carry out an isomerization reaction. After the mother liquor recovery system (106) recovers phenol and the bisphenol A adduct, a part of the crystallization mother liquor of the recovery system obtained is sent to a decomposition rearrangement reactor (108) to carry out a decomposition rearrangement reaction. The obtained decomposition rearrangement product is sent to the mother liquor recovery system (106). In the above isomerization reaction, the catalyst and the mother liquor are brought into contact by a fixed bed reaction. The reaction temperature is 50 - 90 °C, the reaction pressure is 0.1 - 1.0 MPaA, and the liquid hourly space velocity is 0.1 - 10 h -1 is.

[0017] Step (c): The isomerization product at the outlet of the isomerization reactor (107) is sent to the mother liquor recovery system (106), crystallized with phenol via the crystallization reactor (103) to obtain a bisphenol A adduct, enters the dephenolization reactor (104), and phenol is removed to obtain product bisphenol A.

[0018] The crystallization mother liquor of the recovery system in step (a) is a mixture containing 2,4-bisphenol A, phenol, and a bisphenol A adduct, and the isomerization reactor is a fixed-bed reactor.

[0019] The sulfonic acid group-containing metal-organic framework catalyst in step (b) is formed by the coordination bonding of metal ions or metal clusters and organic ligands. The metals contained are one or more combinations of Al, Mg, Ti, Cr, Fe, Cu, Zn, Zr, Ce, and Hf. The organic ligands contained are one or more combinations of terephthalic acid, trimesic acid, and imidazole compounds. The pore diameter of the catalyst is 0.5 nm to 10 nm, the specific surface area is 100 m 2 / g to 5000 m 2 / g, and the sulfonic acid group content is 0.01 mmol / g to 8.0 mmol / g.

[0020] The sulfonic acid group-containing metal-organic framework catalyst is obtained by any of the preparation methods of one-step synthesis, acid treatment after synthesis, or oxidation treatment after synthesis.

[0021] Preparation method for one-step synthesis of sulfonic acid group-containing metal-organic framework catalyst: Dissolve a metal precursor salt and a sulfonic acid group-containing organic ligand in N,N-dimethylformamide, stir, and then allow to stand for crystallization in a crystallization kettle at 140°C to 160°C for 24 hours to 36 hours. Filter the obtained crystallization product, wash it with methanol and N,N-dimethylformamide, and after drying, obtain a sulfonic acid group-containing metal-organic framework material. The metal precursor salt is a combination of one or more of oxides, nitrates, chloride salts, and acetylacetonates of Al, Mg, Ti, Cr, Fe, Cu, Zn, Zr, Ce, and Hf. The sulfonic acid group-containing organic ligand is a combination of one or more of benzoic acid having a sulfonic acid group, terephthalic acid having a sulfonic acid group, trimesic acid having a sulfonic acid group, and imidazole compounds having a sulfonic acid group.

[0022] Preparation method for post-synthesis acid treatment of the sulfonic acid group-containing metal-organic framework catalyst: Dissolve a metal precursor salt and an organic ligand in N,N-dimethylformamide, stir, and then allow to stand for crystallization in a crystallization kettle at 120°C to 160°C for 24 hours to 48 hours. Filter the obtained crystallization product, wash it with methanol and N,N-dimethylformamide, and after drying, obtain a metal-organic framework precursor. Put the obtained metal-organic framework material into a reactor lined with polytetrafluoroethylene, add an acidic liquid, and perform a sulfonation treatment at 100°C to 180°C for 24 hours. Filter, wash, and dry the obtained product to obtain a sulfonic acid group-containing metal-organic framework material. The metal precursor salt is a combination of one or more of oxides, nitrates, chloride salts, and acetylacetonates of Al, Mg, Ti, Cr, Fe, Cu, Zn, Zr, Ce, and Hf. The organic ligand is a combination of one or more of terephthalic acid, trimesic acid, and imidazole compounds that do not contain an amino group or contain an amino group. The metal-organic framework material precursor is formed by the coordination bond between a metal ion or metal cluster and an organic ligand. The acidic liquid is a combination of one or more of sulfuric acid, chlorosulfonic acid, and 1,3-propanesultone.

[0023] Preparation method of post-synthesis oxidation treatment of the sulfonic acid group-containing metal-organic framework catalyst: Dissolve a metal precursor salt and a thiol group-containing organic ligand in N,N-dimethylformamide, stir, and then allow to stand and crystallize in a crystallization kettle at 110 °C to 140 °C for 24 hours to 48 hours. Filter the obtained crystallization product, wash with ethanol, and dry to obtain a metal-organic framework precursor. Put the obtained metal-organic framework material into a reactor lined with polytetrafluoroethylene, add an oxidizing liquid, and perform oxidation treatment at 50 °C to 60 °C for 2 hours to 6 hours. Filter, wash, and dry the obtained product to obtain a sulfonic acid group-containing metal-organic framework material. The metal precursor salt is a combination of one or more of oxides, nitrates, chloride salts, and acetylacetonates of Al, Mg, Ti, Cr, Fe, Cu, Zn, Zr, Ce, and Hf. The organic ligand is a combination of one or more of alkylthiol, aminothiol-containing terephthalic acid, trimesic acid, and imidazole compounds. The metal-organic framework material precursor is formed by the coordination bond between metal ions or metal clusters and organic ligands. The oxidizing liquid is hydrogen peroxide.

Advantages of the Invention

[0024] The advantages and beneficial effects of the present invention are as follows.

[0025] (1) The novel method for reducing by-products in the reaction system of bisphenol A according to the present invention invents an isomerization reaction process of by-products of bisphenol A, efficiently converts the by-products of bisphenol A into bisphenol A, has a high conversion rate of the by-product 2,4-BPA of bisphenol A in the catalytic reaction, can reach 28% to 55%, and also has a high bisphenol A selectivity, which can reach 80% to 90%.

[0026] (2) The novel method for reducing by-products in the reaction system of bisphenol A according to the present invention invents an isomerization reaction catalyst for by-products of bisphenol A, can adjust the amount of sulfonic acid and the pore diameter of the catalyst, has a high conversion rate of by-products of bisphenol A in the catalytic reaction, can reach 28% - 55%, and also has a high selectivity of bisphenol A, which can reach 80% - 90%.

[0027] (3) The novel method for reducing by-products in the reaction system of bisphenol A according to the present invention invents an isomerization reaction catalyst for by-products of bisphenol A, reduces the outflow of acidic functional groups sulfonic acid groups and thiol groups of the catalyst, and is characterized by reducing the corrosion of equipment.

Brief Description of the Drawings

[0028]

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Modes for Carrying Out the Invention

[0029] Hereinafter, the present invention will be described in more detail through specific examples with reference to the accompanying drawings. However, the following examples are merely illustrative and do not limit the present invention, nor are they intended to limit the protection scope of the present invention.

[0030] Hereinafter, the specific implementation process of the method of this application will be described using specific examples.

Example

[0031] (Example 1) In this example, the manufacturing process of bisphenol A is as follows (Figure 1).

[0032] (a) Synthesize phenol and acetone in the bisphenol A reactor (101) to obtain bisphenol A. Send the reaction solution at the outlet of the bisphenol A reactor (101) to the concentration tower (102) for concentration. The light components obtained at the top of the concentration tower (102) as are recovered by the solvent recovery system, a light component and the obtained phenol and acetone are sent to the bisphenol A reactor (101). Send the concentrated reaction solution obtained from the bottom of the concentration tower (102) to the crystallization reactor (103) for crystallization with phenol to obtain a bisphenol A adduct and the crystallization mother liquor of the reactor. The bisphenol A adduct is sent to the de-phenol reactor (104) to remove phenol to obtain the product bisphenol A. The de-phenol mother liquor is sent to the mother liquor recovery system (106). The crystallization mother liquor of the reactor is sent to the mother liquor recovery system (106) to recover the mother liquor. The phenol recovered by the mother liquor recovery system (106) is sent to the bisphenol A reactor (101), and the bisphenol A adduct recovered by the mother liquor recovery system (106) is sent to the crystallization reactor (103).

[0033] (b) After the mother liquor recovery system (106) recovers phenol and bisphenol A adducts, a part of the crystallization mother liquor of the recovery system obtained is sent to an isomerization reactor (107) storing a sulfonic acid group-containing metal-organic framework catalyst for an isomerization reaction. After the mother liquor recovery system (106) recovers phenol and bisphenol A adducts, the crystallization mother liquor of the recovery system is obtained. A part of the crystallization mother liquor of the recovery system is sent to a decomposition rearrangement reactor (108) for a decomposition rearrangement reaction. The obtained decomposition rearrangement product is sent to the mother liquor recovery system (106), and the isomerization product at the outlet of the isomerization reactor (107) is sent to the mother liquor recovery system (106).

[0034] (c) The isomerization product at the outlet of the isomerization reactor (107) is sent to the mother liquor recovery system (106), and bisphenol A is obtained by crystallization and defluorination.

[0035] One-step synthesis preparation process of the sulfonic acid group-containing metal-organic framework catalyst in this example: The metal precursor salt (10 g of zinc tetrachloride) and the ligand (11.6 g of 2-sulfoterephthalic acid) were dissolved in 800 mL of N,N-dimethylformamide, stirred well, injected into a crystallization kettle, and allowed to stand for crystallization at 140 °C for 24 hours. The obtained crystallization product was filtered, washed with methanol and N,N-dimethylformamide, and dried to obtain a sulfonic acid group-containing metal-organic framework material S1. When the obtained product S1 was analyzed by XRD, the XRD spectrum was as shown in Figure 2, indicating that this product is a sulfonic acid group-containing metal-organic framework catalyst having a structure. From Table 1, it can be seen that the specific surface area of the obtained sample S1 is 960 m 2 / g, the average pore diameter is 4.5 nm, and the sulfonic acid group content is 2.85 mmol / g.

[0036] In this example, the prepared sulfonic acid group-containing metal-organic framework material S1 was put into an isomerization reactor, and the catalyst and the mother liquor were brought into contact by a fixed-bed reaction. The reaction temperature was 50 °C, the reaction pressure was 0.1 MPaA, and the liquid hourly space velocity was preferably 0.1 h -1It was. The isomerization reaction of the mother liquor was catalyzed by the sample of the sulfonic acid group-containing metal-organic framework catalyst S1 obtained in Example 1, and the 2,4-BPA conversion rate was 28% and the bisphenol A selectivity was 80%.

[0037] (Example 2) In this example, the manufacturing process of bisphenol A is the same as that of the bisphenol A manufacturing process in Example 1.

[0038] One-step synthesis preparation process of the sulfonic acid group-containing metal-organic framework catalyst in this example: The metal precursor salt (10 g of hafnium chloride) and the ligand (7.4 g of 4,8-disulfonic acid-2,6-naphthalenedicarboxylic acid) were dissolved in 960 mL of N,N-dimethylformamide, stirred well, injected into a crystallization kettle, and left to crystallize statically at 160 °C for 36 hours. The obtained crystallization product was filtered, washed with ethanol, and dried to obtain the sulfonic acid group-containing metal-organic framework material S2. When the obtained product S2 was analyzed by XRD, the XRD spectrum was as shown in Figure 3, indicating that this product is a sulfonic acid group-containing metal-organic framework catalyst having a structure. From Table 1, it can be seen that the specific surface area of the obtained sample S2 is 821 m 2 / g, the average pore diameter is 6.8 nm, and the sulfonic acid group content is 3.46 mmol / g.

[0039] In this example, the prepared sulfonic acid group-containing metal-organic framework material S2 was put into an isomerization reactor, and the catalyst and the mother liquor were brought into contact by a fixed-bed reaction. The reaction temperature was 70 °C, the reaction pressure was 0.2 MPaA, and the liquid hourly space velocity was preferably 10 h -1 It was. The isomerization reaction of the mother liquor was catalyzed by the sample of the sulfonic acid group-containing metal-organic framework catalyst S2 obtained in Example 2, and the 2,4-BPA conversion rate was 38% and the bisphenol A selectivity was 82%.

[0040] (Example 3) In this example, the manufacturing process of bisphenol A is the same as that of the bisphenol A manufacturing process in Example 1.

[0041] One-step synthesis and preparation process of the sulfonic acid group-containing metal-organic framework catalyst in this example: The metal precursor salt (10 g of aluminum nitrate) and the ligand (8.8 g of 1-sulfonic acid trimesic acid) were dissolved in 780 mL of N,N-dimethylformamide, stirred well, injected into a crystallization kettle, and allowed to stand and crystallize at 150 °C for 30 hours. The obtained crystallization product was filtered, washed with ethanol, and dried to obtain the sulfonic acid group-containing metal-organic framework material S3. When the obtained product S3 was analyzed by XRD, the XRD spectrum was as shown in Figure 4, indicating that this product is a sulfonic acid group-containing metal-organic framework catalyst having a structure. From Table 1, it can be seen that the specific surface area of the obtained sample S3 is 803 m 2 / g, the average pore diameter is 6.5 nm, and the sulfonic acid group content is 3.33 mmol / g.

[0042] In this example, the prepared sulfonic acid group-containing metal-organic framework material S3 was charged into an isomerization reactor, and the catalyst and the mother liquor were brought into contact by a fixed-bed reaction. The reaction temperature was 65 °C, the reaction pressure was 0.2 MPaA, and the liquid hourly space velocity was preferably 10 h -1 . The isomerization reaction of the mother liquor was catalyzed by the sample of the sulfonic acid group-containing metal-organic framework catalyst S3 obtained in Example 3, and the 2,4-BPA conversion rate was 39% and the bisphenol A selectivity was 84%.

[0043] (Example 4) In this example, the production process of bisphenol A is the same as the bisphenol A production process of Example 1.

[0044] Preparation process of post-acid treatment after synthesis of sulfonic acid group-containing metal-organic framework catalyst in this example: Dissolve a metal precursor salt (10.5 g of zirconium tetrachloride) and a ligand (10.5 g of terephthalic acid) in 800 mL of N,N-dimethylformamide, stir well, pour it into a crystallization kettle, and let it stand for crystallization at 120 °C for 24 hours. The obtained crystallization product was filtered, washed with methanol and N,N-dimethylformamide, and dried to obtain a metal-organic framework material. The obtained metal-organic framework material was put into a reactor lined with polytetrafluoroethylene, an acidic liquid (100 mL of chlorosulfonic acid) was added, and sulfonation treatment was carried out at 100 °C for 24 hours. The obtained product was filtered, washed, and dried to obtain a sulfonic acid group-containing metal-organic framework material S4. When the obtained product S4 was analyzed by XRD, the XRD spectrum was as shown in Figure 5, indicating that this product is a sulfonic acid group-containing metal-organic framework catalyst having a structure. From Table 1, it can be seen that the specific surface area of the obtained sample S4 is 793 m 2 / g, the average pore diameter is 8.5 nm, and the sulfonic acid group content is 5.57 mmol / g.

[0045] In this example, the manufacturing process of bisphenol A is the same as that of the bisphenol A manufacturing process in Example 1.

[0046] In this example, the prepared sulfonic acid group-containing metal-organic framework material S4 was put into an isomerization reactor, and the catalyst and the mother liquor were brought into contact by a fixed-bed reaction. The reaction temperature was 90 °C, the reaction pressure was 0.5 MPaA, and the liquid hourly space velocity was preferably 0.5 h -1 -1. The sample of the sulfonic acid group-containing metal-organic framework catalyst S4 obtained in Example 4 was used to catalyze the isomerization reaction of the mother liquor, and the 2,4-BPA conversion rate was 37% and the bisphenol A selectivity was 90%.

[0047] (Example 5) In this example, the manufacturing process of bisphenol A is the same as that of the bisphenol A manufacturing process in Example 1.

[0048] Preparation process of post - acid treatment after synthesis of sulfonic acid group - containing metal - organic framework catalyst in this example: Dissolve a metal precursor salt (7.6 g of ferric nitrate nonahydrate) and a ligand (6.5 g of trimesic acid) in 700 mL of N,N - dimethylformamide, stir well, pour it into a crystallization kettle, and let it stand for crystallization at 160 °C for 48 hours. The obtained crystallization product was filtered, washed with ethanol, and dried to obtain a metal - organic framework material. The obtained metal - organic framework material was put into a reactor lined with polytetrafluoroethylene, an acidic liquid (100 mL of 1,3 - propane sultone) was added, and sulfonation treatment was carried out at 180 °C for 24 hours. The obtained product was filtered, washed, and dried to obtain a sulfonic acid group - containing metal - organic framework material S5. When the obtained product S5 was analyzed by XRD, the XRD spectrum was as shown in Figure 6, indicating that this product is a sulfonic acid group - containing metal - organic framework catalyst with a structure. From Table 1, it can be seen that the specific surface area of the obtained sample S5 is 755 m 2 / g, the average pore diameter is 9.2 nm, and the sulfonic acid group content is 4.22 mmol / g.

[0049] In this example, the production process of bisphenol A is the same as that in Example 1 for the production process of bisphenol A.

[0050] In this example, the prepared sulfonic acid group - containing metal - organic framework material S5 was put into an isomerization reactor, and the catalyst and the mother liquor were brought into contact by a fixed - bed reaction. The reaction temperature was 60 °C, the reaction pressure was 1.0 MPaA, and the liquid hourly space velocity was preferably 0.2 h -1 . The sample of the sulfonic acid group - containing metal - organic framework catalyst S5 obtained in Example 5 was used to catalyze the isomerization reaction of the mother liquor, and the 2,4 - BPA conversion rate was 43% and the bisphenol A selectivity was 90%.

[0051] (Example 6) In this example, the production process of bisphenol A is the same as that in Example 1 for the production process of bisphenol A.

[0052] Preparation process of post-acid treatment after synthesis of sulfonic acid group-containing metal-organic framework catalyst in this example: Dissolve a metal precursor salt (10 g of copper nitrate) and a ligand (6.5 g of trimesic acid) in 700 mL of N,N-dimethylformamide, stir well, pour it into a crystallization kettle, and let it stand for crystallization at 130 °C for 48 hours. The obtained crystallization product was filtered, washed with ethanol, and dried to obtain a metal-organic framework material. The obtained metal-organic framework material was put into a reactor lined with polytetrafluoroethylene, an acidic liquid (100 mL of 1,3-propanesultone) was added, and sulfonation treatment was carried out at 180 °C for 24 hours. The obtained product was filtered, washed, and dried to obtain a sulfonic acid group-containing metal-organic framework material S6. When the obtained product S6 was analyzed by XRD, the XRD spectrum was as shown in Figure 7, indicating that this product is a sulfonic acid group-containing metal-organic framework catalyst having a structure. From Table 1, it can be seen that the specific surface area of the obtained sample S6 is 783 m 2 / g, the average pore diameter is 9.4 nm, and the sulfonic acid group content is 4.36 mmol / g.

[0053] In this example, the production process of bisphenol A is the same as that of the bisphenol A production process in Example 1.

[0054] In this example, the prepared sulfonic acid group-containing metal-organic framework material S6 was put into an isomerization reactor, and the catalyst and the mother liquor were brought into contact by a fixed-bed reaction. The reaction temperature was 65 °C, the reaction pressure was 1.0 MPaA, and the liquid hourly space velocity was preferably 0.2 h -1 -1. The sample of the sulfonic acid group-containing metal-organic framework catalyst S6 obtained in Example 6 catalyzed the isomerization reaction of the mother liquor, and the 2,4-BPA conversion rate was 47% and the bisphenol A selectivity was 88%.

[0055] (Example 7) In this example, the production process of bisphenol A is the same as that of the bisphenol A production process in Example 1.

[0056] Preparation process of post-oxidation treatment for the sulfonic acid group-containing metal-organic framework catalyst in this example: Dissolve the metal precursor salt (10 g of chromium nitrate) and the ligand (8.3 g of 2,5-dimercaptoterephthalic acid) in 660 mL of N,N-dimethylformamide, stir well, inject into a crystallization kettle, and let it stand for crystallization at 110 °C for 24 hours. The obtained crystallization product was filtered, washed with ethanol, and dried to obtain a metal-organic framework material. The obtained metal-organic framework material was put into a reactor lined with polytetrafluoroethylene, hydrogen peroxide (20 mL) as the oxidation liquid was added, and it was subjected to oxidation treatment at 50 °C for 2 hours. The obtained product was filtered, washed, and dried to obtain a sulfonic acid group-containing metal-organic framework material S7. When the obtained product S7 was analyzed by XRD, the XRD spectrum was as shown in Figure 8, indicating that this product is a sulfonic acid group-containing metal-organic framework catalyst having a structure. From Table 1, it can be seen that the specific surface area of the obtained sample S7 is 726 m 2 / g, the average pore diameter is 10.5 nm, and the sulfonic acid group content is 6.02 mmol / g.

[0057] In this example, the production process of bisphenol A is the same as that of the bisphenol A production process in Example 1.

[0058] In this example, the prepared sulfonic acid group-containing metal-organic framework material S7 was put into an isomerization reactor, and the catalyst and the mother liquor were brought into contact by a fixed-bed reaction. The reaction temperature was 80 °C, the reaction pressure was 0.7 MPaA, and the liquid hourly space velocity was preferably 3.0 h -1 . The isomerization reaction of the mother liquor was catalyzed by the sample of the sulfonic acid group-containing metal-organic framework catalyst S7 obtained in Example 7, and the conversion rate of 2,4-BPA was 55% and the selectivity of bisphenol A was 87%.

[0059] (Example 8) In this example, the production process of bisphenol A is the same as that of the bisphenol A production process in Example 1.

[0060] Preparation process of post-oxidation treatment for the sulfonic acid group-containing metal-organic framework catalyst in this example: Dissolve the metal precursor salt (10 g of titanium chloride) and the ligand (7.4 g of 4,8-dimercapto-2,6-naphthalenedicarboxylic acid) in 850 mL of N,N-dimethylformamide, stir well, inject into a crystallization kettle, and let it stand for crystallization at 140 °C for 48 hours. Filter the obtained crystallization product, wash it with ethanol, and after drying, obtain a metal-organic framework material. Put the obtained metal-organic framework material into a reactor lined with polytetrafluoroethylene, add the oxidation liquid (35 mL of hydrogen peroxide), carry out oxidation treatment at 60 °C for 6 hours, filter, wash, and dry the obtained product to obtain the sulfonic acid group-containing metal-organic framework material S8. When the obtained product S8 was analyzed by XRD, the XRD spectrum was as shown in Figure 9, indicating that this product is a sulfonic acid group-containing metal-organic framework catalyst with a structure. From Table 1, it can be seen that the specific surface area of the obtained sample S8 is 866 m 2 / g, the average pore diameter is 5.7 nm, and the sulfonic acid group content is 4.38 mmol / g.

[0061] In this example, the production process of bisphenol A is the same as that of the bisphenol A production process in Example 1.

[0062] In this example, the prepared sulfonic acid group-containing metal-organic framework material S8 was put into an isomerization reactor, and the catalyst and the mother liquor were brought into contact by a fixed-bed reaction. The reaction temperature was 70 °C, the reaction pressure was 0.5 MPaA, and the liquid hourly space velocity was preferably 7.0 h -1 . The sample of the sulfonic acid group-containing metal-organic framework catalyst S8 obtained in Example 8 catalyzed the isomerization reaction of the mother liquor, and the conversion rate of 2,4-BPA was 48% and the selectivity of bisphenol A was 89%.

[0063] (Example 9) In this example, the production process of bisphenol A is the same as that of the bisphenol A production process in Example 1.

[0064] Preparation process of post-oxidation treatment for the sulfonic acid group-containing metal-organic framework catalyst in this example: Dissolve the metal precursor salts (6.6 g of magnesium nitrate and 3.4 g of cerium nitrate) and the ligand (6.9 g of 2,5-dimercaptoterephthalic acid) in 820 mL of N,N-dimethylformamide, stir well, pour into a crystallization kettle, and let it stand for crystallization at 120 °C for 36 hours. The obtained crystallization product was filtered, washed with ethanol, and dried to obtain a metal-organic framework material. The obtained metal-organic framework material was put into a reactor lined with polytetrafluoroethylene, hydrogen peroxide (40 mL) as the oxidation liquid was added, and oxidation treatment was carried out at 55 °C for 4 hours. The obtained product was filtered, washed, and dried to obtain a sulfonic acid group-containing metal-organic framework material S9. When the obtained product S9 was analyzed by XRD, the XRD spectrum was as shown in Figure 10, indicating that this product is a sulfonic acid group-containing metal-organic framework catalyst with a structure. From Table 1, it can be seen that the specific surface area of the obtained sample S9 is 833 m 2 / g, the average pore diameter is 5.3 nm, and the sulfonic acid group content is 4.06 mmol / g.

[0065] In this example, the manufacturing process of bisphenol A is the same as that in Example 1 for the production of bisphenol A.

[0066] In this example, the prepared sulfonic acid group-containing metal-organic framework material S9 was put into an isomerization reactor, and the catalyst and the mother liquor were brought into contact in a fixed-bed reaction. The reaction temperature was 65 °C, the reaction pressure was 0.5 MPaA, and the liquid hourly space velocity was preferably 6.0 h -1 -1. The sample of the sulfonic acid group-containing metal-organic framework catalyst S9 obtained in Example 9 was used to catalyze the isomerization reaction of the mother liquor, and the conversion rate of 2,4-BPA was 45% and the selectivity for bisphenol A was 87%.

[0067] In the above examples, the calculation methods for the conversion rate of 2,4-BPA and the selectivity for bisphenol A are as follows.

[0068] (Equation 1) 2,4 - BPA conversion rate = (2,4 - BPA charged amount - unreacted 2,4 - BPA amount) / 2,4 - BPA charged amount × 100%.

[0069] (Equation 2) Bisphenol A selectivity = amount of bisphenol A produced / amount of 2,4 - BPA product × 100%.

[0070] The method described in the present invention proposes a method for isomerizing a mixture containing 2,4 - bisphenol A, phenol, and bisphenol A adduct as a raw material for the by - product 2,4 - bisphenol A in the production of bisphenol A to convert 2,4 - bisphenol A into bisphenol A. In order to reflect the effect of the catalyst in the method described in the present invention to catalyze 2,4 - bisphenol A to be converted into bisphenol A, in Examples 1 to 9, an isomerization reaction was carried out using 2,4 - bisphenol A as a raw material, and the obtained results are shown in Table 2. It can be seen from Table 2 that the sulfonic acid group - containing metal - organic framework catalysts S1 to S9 samples obtained in Examples 1 to 9 have good 2,4 - BPA conversion rates (28% - 55%) and high bisphenol A selectivities (80% - 90%) in the products. This indicates that the sulfonic acid group - containing metal - organic framework catalyst described in the present invention can catalyze the efficient isomerization of 2,4 - BPA to prepare bisphenol A. From the perspective of the effect of the catalyst to catalyze the isomerization reaction of 2,4 - bisphenol A to produce bisphenol A, the method described in the present invention can catalytically convert the by - product 2,4 - BPA in bisphenol A, significantly reduce the content of the by - product 2,4 - BPA, and convert 2,4 - BPA into bisphenol A with a high selectivity. In short, from the above analysis, by using the method described in the present invention, the amount of the by - product 2,4 - bisphenol A in the production of bisphenol A can be significantly reduced, 2,4 - bisphenol A can be converted into bisphenol A with a high selectivity, and the yield of bisphenol A can be improved.

[0071]

Table 1

[0072]

Table 2

[0073] The preferred embodiments of the present disclosure have been described in detail with reference to the accompanying drawings. However, the present disclosure is not limited to the above embodiments, and various simple modifications can be made to the technical means of the present disclosure within the scope of the technical idea of the present disclosure, and such simple modifications are equally included in the protection scope of the present disclosure.

[0074] In addition, each specific technical feature described in the above specific embodiments can be combined in any appropriate manner without contradiction. However, to avoid unnecessary repetition, various combinations possible in the present disclosure are omitted.

[0075] In addition, various embodiments of the present disclosure can be arbitrarily combined, and as long as they do not conflict with the idea of the present disclosure, they should also be regarded as the content disclosed in the present disclosure.

Description of Reference Numerals

[0076] 101 Bisphenol A reactor 102 Concentration tower 103 Crystallization reactor 104 Dephenolization reactor 105 Solvent recovery system 106 Mother liquor recovery system 107 Isomerization reactor 108 Decomposition rearrangement reactor

Claims

1. A method for reducing by-products in a reaction system of bisphenol A, comprising the steps of: (a) sending a mother liquor produced after reacting, concentrating, crystallizing and separating phenol and acetone to a mother liquor recovery system; (b) contacting the mother liquor obtained by the mother liquor recovery system with a sulfonic acid group-containing metal organic framework catalyst to carry out an isomerization reaction; and (c) sending the product obtained by the isomerization reaction to the mother liquor recovery system, and obtaining bisphenol A through crystallization and dephenolization, The sulfonic acid group-containing metal organic framework catalyst in the step (b) is formed by bonding a metal ion or a metal cluster to an organic ligand via a coordinate bond, the metals contained are one or more combinations of Al, Mg, Ti, Cr, Fe, Cu, Zn, Zr, Ce, and Hf, the organic ligands contained are one or more combinations of terephthalic acid, trimesic acid, and imidazole compounds, the pore diameter of the catalyst is 0.5 nm to 10 nm, and the specific surface area is 100 m. ２ / g to 5000m ２ / g, the content of sulfonic acid groups is 0.01 mmol / g to 8.0 mmol / g, The sulfonic acid group-containing metal organic framework catalyst is obtained by a preparation method of one-step synthesis, post-synthesis acid treatment, or post-synthesis oxidation treatment; A method for preparing the one-step synthesis of the sulfonic acid group-containing metal organic framework catalyst: a metal precursor salt and a sulfonic acid group-containing organic ligand are dissolved in N,N-dimethylformamide, stirred, and then allowed to stand and crystallize in a crystallizer at 140°C to 160°C for 24 to 36 hours. The crystallized product is filtered, washed with methanol and N,N-dimethylformamide, and dried to obtain a sulfonic acid group-containing metal organic framework material, the metal precursor salt being a combination of one or more of oxides, nitrates, chlorides, and acetylacetonates of one or more combinations of Al, Mg, Ti, Cr, Fe, Cu, Zn, Zr, Ce, and Hf, the sulfonic acid group-containing organic ligand being a combination of one or more of benzoic acid having a sulfonic acid group, terephthalic acid having a sulfonic acid group, trimesic acid having a sulfonic acid group, and imidazole compound having a sulfonic acid group, The method for preparing the sulfonic acid group-containing metal organic framework catalyst by post-synthesis acid treatment is as follows: the metal precursor salt and organic ligand are dissolved in N,N-dimethylformamide, stirred, and then left to crystallize in a crystallizer at 120°C to 160°C for 24 to 48 hours. The crystallized product is filtered, washed with methanol and N,N-dimethylformamide, and dried to obtain a metal organic framework precursor. The metal organic framework material is placed in a polytetrafluoroethylene-lined reactor, an acidic liquid is added, and sulfonation is performed at 100°C to 180°C for 24 hours. The product is filtered, washed, dried, and then used as a sulfonic acid group-containing metal organic framework. a metal-organic framework material is obtained, the metal precursor salt being a combination of one or more of oxides, nitrates, chlorides, and acetylacetonates of one or more of Al, Mg, Ti, Cr, Fe, Cu, Zn, Zr, Ce, and Hf; the organic ligand being a combination of one or more of terephthalic acid, trimesic acid, and imidazole compounds that do not contain amino or contain amino; the metal-organic framework material precursor is formed by bonding a metal ion or a metal cluster to the organic ligand via a coordinate bond; and the acidic liquid being a combination of one or more of sulfuric acid, chlorosulfonic acid, and 1,3-propane sultone; The preparation method of the post-synthesis oxidation treatment of the sulfonic acid group-containing metal organic framework catalyst: the metal precursor salt and the thiol group-containing organic ligand are dissolved in N,N-dimethylformamide, stirred, and then left to crystallize in a crystallizer at 110°C to 140°C for 24 to 48 hours. The crystallized product is filtered, washed with ethanol, and dried to obtain a metal organic framework precursor. The metal organic framework material is placed in a polytetrafluoroethylene-lined reactor, an oxidizing liquid is added, and the catalyst is oxidized at 50°C to 60°C for 2 to 6 hours. The product is filtered, washed, dried, and then sulfonated. The metal precursor salt is a combination of one or more of oxides, nitrates, chlorides, and acetylacetonates of one or more of Al, Mg, Ti, Cr, Fe, Cu, Zn, Zr, Ce, and Hf, the organic ligand is a combination of one or more of alkylthiol, terephthalic acid containing aminothiol, trimesic acid, and imidazole compounds, the metal organic framework precursor is formed by bonding a metal ion or a metal cluster to the organic ligand via a coordinate bond, and the oxidizing liquid is hydrogen peroxide. A method for reducing by-products in a reaction system of bisphenol A, comprising:

2. The step (a): synthesizing phenol and acetone in a bisphenol A reactor (101) to obtain bisphenol A, sending the reaction liquid at the outlet of the bisphenol A reactor (101) to a concentration tower (102) to concentrate it, recovering light components obtained at the top of the concentration tower (102) by a solvent recovery system, sending the phenol and acetone obtained as light components to the bisphenol A reactor (101), sending the concentrated reaction liquid obtained from the bottom of the concentration tower (102) to a crystallization reactor (103) to crystallize it with the phenol to obtain a bisphenol A adduct and a crystallization mother liquor of the reactor, and recovering the bisphenol A adduct and the acetone from the crystallization reactor.

2. The method for reducing by-products in a bisphenol A reaction system according to claim 1, characterized in that the phenol A adduct is sent to a dephenolization reactor (104) to remove the phenol to obtain a product bisphenol A, the phenol is sent to a mother liquor recovery system (106), the crystallization mother liquor of the reactor is sent to the mother liquor recovery system (106) to recover the mother liquor, the phenol recovered by the mother liquor recovery system (106) is sent to the bisphenol A reactor (101), and the bisphenol A adduct recovered by the mother liquor recovery system (106) is sent to the crystallization reactor (103).

3. The step (b): A part of the crystallization mother liquor of the recovery system obtained after the mother liquor recovery system (106) recovers the phenol and the bisphenol A adduct is sent to an isomerization reactor (107) containing the sulfonic acid group-containing metal organic framework catalyst to carry out an isomerization reaction, a part of the crystallization mother liquor of the recovery system obtained after the mother liquor recovery system (106) recovers the phenol and the bisphenol A adduct is sent to a cracking and rearrangement reactor (108) to carry out a cracking and rearrangement reaction, and the obtained cracking and rearrangement product is sent to the mother liquor recovery system (106). In the isomerization reaction, the catalyst and the mother liquor are contacted in a fixed bed reaction, the reaction temperature is 50 to 90° C., the reaction pressure is 0.1 to 1.0 MPaA, and the liquid hourly space velocity is 0.1 to 10 h -１ The method for reducing by-products in a reaction system of bisphenol A according to claim 2, characterized in that

4. 4. The method for reducing by-products in a bisphenol A reaction system according to claim 3, characterized in that in step (c): the isomerization product at the outlet of the isomerization reactor (107) is sent to the mother liquor recovery system (106), passed through the crystallization reactor (103) and crystallized with the phenol to obtain the bisphenol A adduct, and then enters the dephenolization reactor (104) to remove the phenol to obtain the product bisphenol A.

5. The method for reducing by-products in a reaction system of bisphenol A according to claim 3, wherein the crystallization mother liquor in the recovery system in the step (a) is a mixture containing 2,4-bisphenol A, the phenol, and the bisphenol A adduct, and the isomerization reactor is a fixed-bed reactor.

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