Preparation of supported catalyst and application of synthesis of phenyldicarboxylic chloride

Abstract

The application discloses a preparation of a solid carrier catalyst and an application of the solid carrier catalyst in synthesis of phenyldiformyl chloride. Specifically, a transition metal inorganic salt and a small boron-containing molecule are dissolved in water to obtain a premix solution; then, a carrier is added into the premix solution, and ultrasonic oscillation treatment is carried out under a magnetic field condition; after standing, solid-liquid separation is carried out to obtain a doped porous material; finally, the doped porous material is calcined, impregnated with 1-benzyl-2,3-dimethyl imidazole hexafluoroantimonate and 1-butyl-3-methyl imidazole dicyandiamide salt, and post-treated, and the solid carrier catalyst is obtained. The solid carrier catalyst can be used for a catalyst for preparing phenyldiformyl chloride (terephthaloyl chloride) through a reaction of terephthalic acid and thionyl chloride, promotes the reaction at a lower temperature, has a high product yield and high purity, and has no amplification effect.

Description

Technical Field

[0001] This invention belongs to the field of chemical synthesis technology and relates to the preparation of a supported catalyst and its application in the synthesis of phenyldicarboxylic acid chloride. Background Technology

[0002] Terephthaloyl chloride is widely used in the dye industry, primarily for the synthesis of dyes such as Violet B, Blue BB, and Blue RR. It can also be used to produce Vat Orange 3G, Vat SGK, Vat Olive R, and Vat Gray BG. Terephthaloyl chloride can also be used to synthesize organic peroxides such as benzoyl peroxide, which can be used as a curing catalyst for polyester resins and an initiator for resin polymerization. Furthermore, terephthaloyl chloride is used in the production of rubber additives, benzophenone-based ultraviolet absorbers, and other fine chemicals.

[0003] There are many methods for preparing terephthaloyl chloride. The reaction of benzoic acid and thionyl chloride produces benzoyl chloride, as well as gaseous SO2 and HCl, with no solid byproducts remaining, making the product easy to purify. However, due to the relatively high price of the raw material thionyl chloride, it is still used for laboratory synthesis despite long-term research and development. Therefore, it is necessary to develop new reaction routes for terephthaloyl chloride.

[0004] Patent CN103724188B discloses a method for preparing terephthaloyl chloride. It involves using one or more of iron powder, iron salts, and iron-containing complexes as catalysts, mixing thionyl chloride with terephthalic acid, heating the mixture, distilling off excess thionyl chloride, and then distilling under reduced pressure to obtain the product, terephthaloyl chloride. This patented technology achieves a yield of up to 96%, using ferrous aspartate as a catalyst, at a reaction temperature of 120°C, and for a reaction time of 16 hours. However, this patented technology is only suitable for laboratory preparation. Scale-up results in a significant reduction in product yield and purity, and the high reaction temperature and long reaction time lead to high production costs. Summary of the Invention

[0005] In view of this, the purpose of the present invention is to provide a method for preparing a supported catalyst and its application in the synthesis of phenyldicarboxylic acid chloride.

[0006] To achieve the above objectives, the present invention provides the following technical solution:

[0007] A method for preparing a supported catalyst, comprising the following specific steps:

[0008] (1) First, dissolve the transition metal inorganic salt and boron-containing small molecules in water to obtain a premixed solution;

[0009] (2) Then the carrier is added to the premixed liquid, ultrasonically oscillated under magnetic field conditions, allowed to stand, and solid-liquid separation is performed to obtain the doped porous material.

[0010] (3) Finally, the doped porous material is calcined, impregnated with 1-benzyl-2,3-dimethylimidazolium hexafluoroantimonate and 1-butyl-3-methylimidazolium dicyandiamide salt, and then post-treated to obtain the supported catalyst described above.

[0011] The carrier is selected from one or more of activated alumina, molecular sieve, diatomaceous earth, activated carbon, organobentonite, foamed carbon or modified foamed carbon, and the modified foamed carbon is obtained by sequentially modifying cerium-doped foamed carbon with carbon nanotubes and nano-titanium dioxide.

[0012] Preferably, the mass ratio of transition metal inorganic salt, boron-containing small molecule, water, and carrier is 1-5:1-3:120-130:100.

[0013] Preferably, the carrier is foamed carbon, which is prepared by heating sucrose and then quickly transferring it to a forced-air drying oven for drying. The heating conditions are: heating at 150-160°C for 5-7 minutes; drying at 175-180°C for 8-10 minutes.

[0014] Preferably, the carrier is modified foamed carbon, which is prepared by the following method:

[0015] (A) First, cerium nitrate hexahydrate is mixed evenly with sucrose, heated and mixed, and then quickly transferred to a forced-air drying oven to dry, thus obtaining cerium-doped foam carbon;

[0016] (B) Then carbon nanotubes were grown in situ on cerium-doped foam carbon by chemical vapor deposition to obtain pretreated foam carbon;

[0017] (C) Finally, nano-titanium dioxide is electrophoretically deposited on the surface of the pretreated foam carbon to obtain the final product.

[0018] More preferably, in step (A), the mass ratio of cerium nitrate hexahydrate to sucrose is 0.3 to 0.4:1.

[0019] More preferably, in step (A), the heating and mixing conditions are: heating and mixing at 150-160°C for 5-7 minutes.

[0020] More preferably, in step (A), the drying temperature is 175-180°C and the drying time is 8-10 minutes.

[0021] Further preferred, in step (B), the specific conditions for chemical vapor deposition are as follows: using a 0.05–0.1 mg / mL ferrocene xylene solution as a catalyst; using acetylene as the carbon source, and argon and hydrogen in a volume ratio of 7–8:2–3 as a protective atmosphere; heating to 800–900 °C at a rate of 10–12 °C / min; and a growth time of 15–20 minutes.

[0022] A further preferred embodiment of step (C) is as follows: pretreated foamed carbon is used as the negative electrode, and graphite is used as the positive electrode, for electrophoretic deposition in a suspension; the suspension is obtained by dispersing magnesium chloride hexahydrate and nano-titanium dioxide in anhydrous ethanol; the electrophoretic deposition conditions are: current density 15-20 mA / cm². 2 The deposition time is 3 to 5 minutes.

[0023] More preferably, the mass ratio of magnesium chloride hexahydrate, nano titanium dioxide, and anhydrous ethanol is 0.1:1.2-1.5:30-40.

[0024] Preferably, in step (1), the transition metal inorganic salt is selected from one or more inorganic salts of iron, cobalt, nickel, copper or zinc, and the anion of the inorganic salt is any one of nitrate, sulfate or chloride ions.

[0025] Preferably, in step (1), the boron-containing small molecule is selected from any one of boric acid, sodium borate, phenylboronic acid or sodium borohydride.

[0026] Preferably, in step (2), the magnetic field strength is 50-70 mT, the ultrasonic frequency is 25-35 kHz, the power is 800-900 W, and the processing time is 2-3 hours.

[0027] Preferably, in step (2), the settling time is 30 to 40 minutes.

[0028] Preferably, in step (3), the calcination conditions are: under a nitrogen atmosphere, the temperature is increased to 700-800℃ at a rate of 15-20℃ / min, and the temperature is maintained for calcination for 6-8 hours.

[0029] Preferably, in step (3), the calcined doped porous material is naturally cooled to room temperature (25°C) and then immersed in 1-butyl-3-methylimidazolium hexafluoroantimonate and 1-butyl-3-methylimidazolium dicyandiamide salt for 50-60 minutes. The mass ratio of the calcined doped porous material, 1-butyl-3-methylimidazolium hexafluoroantimonate and 1-butyl-3-methylimidazolium dicyandiamide salt is 1:2-3:2-3.

[0030] Preferably, in step (3), the post-processing includes: filtering to obtain the solid, washing with deionized water, and drying.

[0031] A supported catalyst is obtained by the aforementioned preparation method.

[0032] The aforementioned application of a supported catalyst in the synthesis of phenyldicarboxylic acid chloride.

[0033] A method for synthesizing phenyl dicarboxylic acid chloride involves mixing terephthalic acid (PTA), thionyl chloride (SOCl2), and the aforementioned supported catalyst at a mass ratio of 1:3-4:0.008-0.01, heating the mixture to 70-80°C at a rate of 10-12°C / min, maintaining the temperature for 3-4 hours, and then performing post-treatment to obtain the phenyl dicarboxylic acid chloride.

[0034] Preferably, the post-treatment includes: sequentially absorbing the reaction tail gas with water and a 30% sodium hydroxide solution, distilling to recover unreacted thionyl chloride, filtering to recover the supported catalyst, and distilling the filtrate under reduced pressure to obtain phenyldicarboxylic acid chloride (TPC).

[0035] More preferably, the vacuum degree of the reduced pressure distillation is 300-400 Pa, and the fraction receiving temperature is 110-120℃.

[0036] The beneficial effects of this invention are as follows:

[0037] This invention provides a method for preparing a supported catalyst and its application in the synthesis of phenyldicarboxylic acid chloride. Specifically, a transition metal inorganic salt and a boron-containing small molecule are first dissolved in water to obtain a premixed solution. Then, a support is added to the premixed solution, and the mixture is subjected to ultrasonic oscillation under a magnetic field. After settling, solid-liquid separation is performed to obtain a doped porous material. Finally, the doped porous material is calcined, impregnated with 1-benzyl-2,3-dimethylimidazolium hexafluoroantimonate and 1-butyl-3-methylimidazolium dicyandiamide salts, and post-treated to obtain the final product. The supported catalyst obtained by this invention can be used as a catalyst for the reaction of terephthalic acid and thionyl chloride to prepare phenyldicarboxylic acid chloride (terephthaloyl chloride). It promotes the reaction at lower temperatures, resulting in high product yield, high purity, and no scale-up effect.

[0038] The supported catalyst of this invention mainly comprises three parts: a support, a transition metal inorganic salt, and boron-containing small molecules. The support is selected from one or more of activated alumina, molecular sieves, diatomaceous earth, activated carbon, organobentonite, carbon foam, or modified carbon foam. In particular, the modified carbon foam is obtained by sequentially modifying cerium-doped carbon foam with carbon nanotubes and nano-titanium dioxide. This invention utilizes a premixed liquid containing transition metal inorganic salts and boron-containing small molecules to treat the support, followed by ultrasonic oscillation under a magnetic field to promote the loading of transition metal ions and boron-containing small molecules onto the support, thereby obtaining a doped porous material. The support of this invention has abundant pores and a large specific surface area, loading transition metal ions and boron-containing small molecules to form a Lewis acid catalyst, promoting the reaction of terephthalic acid and thionyl chloride to produce phenyldicarboxylic acid chloride.

[0039] This invention further utilizes modified foamed carbon as a carrier, which is obtained by sequentially modifying cerium-doped foamed carbon with carbon nanotubes and nano-titanium dioxide. The foamed carbon is rich in pores and has a large specific surface area. Cerium doping and modification with carbon nanotubes and nano-titanium dioxide further increase the specific surface area (cerium doping alters the lattice arrangement of the foamed carbon, forming a fine grain structure, thereby increasing the specific surface area; carbon nanotubes are grown in situ on the cerium-doped foamed carbon, with a tubular microstructure, and nano-titanium dioxide is electrophoretically deposited in a spherical shape; the different shapes of nanomaterials are arranged in a staggered manner, forming more micropores, further increasing the specific surface area); on the other hand, cerium, carbon nanotubes, and nano-titanium dioxide... Titanium dioxide provides more catalytic sites, and its synergistic effect with subsequently added transition metals and boron-containing small molecules further improves the catalytic effect. This is because the reaction mechanism of terephthalic acid and thionyl chloride includes the attack of carboxyl oxygen on the positively charged sulfur center, the departure of chlorine atoms, proton transfer and chlorine substitution. Cerium doping provides Lewis acid sites, boron-containing small molecules promote the formation of Lewis acids, nano-titanium dioxide generates electron-hole pairs, carbon nanotubes rapidly transport electrons and improve the separation efficiency of charge carriers, and transition metals further optimize electron transport based on the d / f orbital characteristics of metal centers and the electronic state regulation effect, thereby synergistically promoting the reaction of terephthalic acid and thionyl chloride.

[0040] This invention involves calcining a doped porous material and then impregnating it with 1-benzyl-2,3-dimethylimidazolium hexafluoroantimonate and 1-butyl-3-methylimidazolium dicyandiamide. These two ionic liquids are loaded onto a support. On one hand, the ionic conductivity of the ionic liquids promotes the phase transfer reaction between terephthalic acid and thionyl chloride. On the other hand, the hexafluoroantimonate and dicyandiamide salts in the ionic liquids modify the support, giving it both cations and anions on its surface (ionic liquids are formed by the combination of cations and anions through ionic bonds; the cations and anions directly modify the support, resulting in the simultaneous presence of cations and anions on the support surface). This promotes rapid ion exchange of the reactants. The hexafluoroantimonate combines with the metal cations in the system to form a coordination structure, resulting in a high charge density at the metal center and stronger Lewis acidity. The dicyandiamide salt forms an azacyclopropane structure, further coordinating with other metal cations, further improving catalytic performance and promoting the reaction.

[0041] The supported catalyst of this invention has a large specific surface area, reducing the difficulty of ion exchange. It maintains sufficient contact with reactants during scale-up production, without affecting the reaction microenvironment, such as temperature distribution, concentration gradient, and reactant residence time, thus avoiding scale-up effects and ensuring reaction efficiency. Using the supported catalyst of this invention, high-purity products can be obtained without complex post-processing. Detailed Implementation

[0042] The preferred embodiments of the present invention will now be described in detail.

[0043] Example 1:

[0044] A method for preparing a supported catalyst, comprising the following specific steps:

[0045] (1) First, dissolve the transition metal inorganic salt and boron-containing small molecules in water to obtain a premixed solution;

[0046] (2) Then the carrier is added to the premixed liquid, ultrasonically oscillated under magnetic field conditions, allowed to stand, and solid-liquid separation is performed to obtain the doped porous material.

[0047] (3) Finally, the doped porous material is calcined, impregnated with 1-benzyl-2,3-dimethylimidazolium hexafluoroantimonate and 1-butyl-3-methylimidazolium dicyandiamide salt, and then post-treated to obtain the supported catalyst described above.

[0048] The carrier is activated alumina.

[0049] The mass ratio of transition metal inorganic salt, boron-containing small molecule, water, and carrier is 1:1:120:100.

[0050] In step (1), the transition metal inorganic salt is ferric nitrate.

[0051] In step (1), the boron-containing small molecule is boric acid.

[0052] In step (2), the magnetic field strength is 50mT, the ultrasonic frequency is 25kHz, the power is 800W, and the processing time is 2 hours.

[0053] In step (2), the settling time is 30 minutes.

[0054] In step (3), the calcination conditions are: under a nitrogen atmosphere, the temperature is increased to 700℃ at 15℃ / min and calcined for 6 hours.

[0055] In step (3), the calcined doped porous material is naturally cooled to room temperature (25°C) and then placed in 1-butyl-3-methylimidazolium hexafluoroantimonate and 1-butyl-3-methylimidazolium dicyandiamide salt and left to stand for 50 minutes. The mass ratio of the calcined doped porous material, 1-butyl-3-methylimidazolium hexafluoroantimonate and 1-butyl-3-methylimidazolium dicyandiamide salt is 1:2:2.

[0056] In step (3), the post-processing includes: filtering to obtain the solid, washing with deionized water, and drying.

[0057] Example 2:

[0058] A method for preparing a supported catalyst, comprising the following specific steps:

[0059] (1) First, dissolve the transition metal inorganic salt and boron-containing small molecules in water to obtain a premixed solution;

[0060] (2) Then the carrier is added to the premixed liquid, ultrasonically oscillated under magnetic field conditions, allowed to stand, and solid-liquid separation is performed to obtain the doped porous material.

[0061] (3) Finally, the doped porous material is calcined, impregnated with 1-benzyl-2,3-dimethylimidazolium hexafluoroantimonate and 1-butyl-3-methylimidazolium dicyandiamide salt, and then post-treated to obtain the supported catalyst described above.

[0062] The carrier is activated carbon.

[0063] The mass ratio of transition metal inorganic salt, boron-containing small molecule, water, and carrier is 5:3:130:100.

[0064] In step (1), the transition metal inorganic salt is cobalt nitrate.

[0065] In step (1), the boron-containing small molecule is sodium borate.

[0066] In step (2), the magnetic field strength is 70mT, the ultrasonic frequency is 35kHz, the power is 900W, and the processing time is 3 hours.

[0067] In step (2), the settling time is 40 minutes.

[0068] In step (3), the calcination conditions are: under a nitrogen atmosphere, the temperature is increased to 800℃ at 20℃ / min and calcined for 8 hours.

[0069] In step (3), the calcined doped porous material is naturally cooled to room temperature (25°C) and then placed in 1-butyl-3-methylimidazolium hexafluoroantimonate and 1-butyl-3-methylimidazolium dicyandiamide salt and left to stand for 60 minutes to soak. The mass ratio of the calcined doped porous material, 1-butyl-3-methylimidazolium hexafluoroantimonate and 1-butyl-3-methylimidazolium dicyandiamide salt is 1:3:3.

[0070] In step (3), the post-processing includes: filtering to obtain the solid, washing with deionized water, and drying.

[0071] Example 3:

[0072] A method for preparing a supported catalyst, comprising the following specific steps:

[0073] (1) First, dissolve the transition metal inorganic salt and boron-containing small molecules in water to obtain a premixed solution;

[0074] (2) Then the carrier is added to the premixed liquid, ultrasonically oscillated under magnetic field conditions, allowed to stand, and solid-liquid separation is performed to obtain the doped porous material.

[0075] (3) Finally, the doped porous material is calcined, impregnated with 1-benzyl-2,3-dimethylimidazolium hexafluoroantimonate and 1-butyl-3-methylimidazolium dicyandiamide salt, and then post-treated to obtain the supported catalyst.

[0076] The mass ratio of transition metal inorganic salt, boron-containing small molecule, water, and carrier is 1:3:120:100.

[0077] The carrier is foamed carbon, which is prepared by heating sucrose and then rapidly transferring it to a forced-air drying oven to obtain foamed carbon. The heating conditions are: heating at 150°C for 7 minutes. The drying temperature is 175°C, and the drying time is 10 minutes.

[0078] In step (1), the transition metal inorganic salt is nickel sulfate.

[0079] In step (1), the boron-containing small molecule is phenylboronic acid.

[0080] In step (2), the magnetic field strength is 50mT, the ultrasonic frequency is 35kHz, the power is 800W, and the processing time is 3 hours.

[0081] In step (2), the settling time is 30 minutes.

[0082] In step (3), the calcination conditions are: under a nitrogen atmosphere, the temperature is increased to 700℃ at 20℃ / min and calcined for 8 hours.

[0083] In step (3), the calcined doped porous material is naturally cooled to room temperature (25°C) and then placed in 1-butyl-3-methylimidazolium hexafluoroantimonate and 1-butyl-3-methylimidazolium dicyandiamide salt and left to stand for 50 minutes. The mass ratio of the calcined doped porous material, 1-butyl-3-methylimidazolium hexafluoroantimonate and 1-butyl-3-methylimidazolium dicyandiamide salt is 1:3:2.

[0084] In step (3), the post-processing includes: filtering to obtain the solid, washing with deionized water, and drying.

[0085] Example 4:

[0086] A method for preparing a supported catalyst, comprising the following specific steps:

[0087] (1) First, dissolve the transition metal inorganic salt and boron-containing small molecules in water to obtain a premixed solution;

[0088] (2) Then the carrier is added to the premixed liquid, ultrasonically oscillated under magnetic field conditions, allowed to stand, and solid-liquid separation is performed to obtain the doped porous material.

[0089] (3) Finally, the doped porous material is calcined, impregnated with 1-benzyl-2,3-dimethylimidazolium hexafluoroantimonate and 1-butyl-3-methylimidazolium dicyandiamide salt, and then post-treated to obtain the supported catalyst.

[0090] The mass ratio of transition metal inorganic salt, boron-containing small molecule, water, and carrier is 5:1:130:100.

[0091] The carrier is cerium-doped foamed carbon, which is prepared by the following method: cerium nitrate hexahydrate is mixed evenly with sucrose, heated and mixed, and then quickly transferred to a forced-air drying oven for drying to obtain cerium-doped foamed carbon. The mass ratio of cerium nitrate hexahydrate to sucrose is 0.3:1. The heating and mixing conditions are: heating and mixing at 160℃ for 5 minutes. The drying temperature is 180℃, and the drying time is 8 minutes.

[0092] In step (1), the transition metal inorganic salt is copper chloride.

[0093] In step (1), the boron-containing small molecule is sodium borohydride.

[0094] In step (2), the magnetic field strength is 70mT, the ultrasonic frequency is 25kHz, the power is 900W, and the processing time is 2 hours.

[0095] In step (2), the settling time is 40 minutes.

[0096] In step (3), the calcination conditions are: under a nitrogen atmosphere, the temperature is increased to 800℃ at 15℃ / min and calcined for 6 hours.

[0097] In step (3), the calcined doped porous material is naturally cooled to room temperature (25°C) and then immersed in 1-butyl-3-methylimidazolium hexafluoroantimonate and 1-butyl-3-methylimidazolium dicyandiamide salt for 60 minutes. The mass ratio of the calcined doped porous material, 1-butyl-3-methylimidazolium hexafluoroantimonate and 1-butyl-3-methylimidazolium dicyandiamide salt is 1:2:3.

[0098] In step (3), the post-processing includes: filtering to obtain the solid, washing with deionized water, and drying.

[0099] Example 5:

[0100] A method for preparing a supported catalyst, comprising the following specific steps:

[0101] (1) First, dissolve the transition metal inorganic salt and boron-containing small molecules in water to obtain a premixed solution;

[0102] (2) Then the carrier is added to the premixed liquid, ultrasonically oscillated under magnetic field conditions, allowed to stand, and solid-liquid separation is performed to obtain the doped porous material.

[0103] (3) Finally, the doped porous material is calcined, impregnated with 1-benzyl-2,3-dimethylimidazolium hexafluoroantimonate and 1-butyl-3-methylimidazolium dicyandiamide salt, and then post-treated to obtain the supported catalyst.

[0104] The mass ratio of transition metal inorganic salt, boron-containing small molecule, water, and carrier is 4:2:125:100.

[0105] The carrier is pretreated foamed carbon, which is prepared by the following method:

[0106] (A) First, cerium nitrate hexahydrate is mixed evenly with sucrose, heated and mixed, and then quickly transferred to a forced-air drying oven to dry, thus obtaining cerium-doped foam carbon;

[0107] (B) Then carbon nanotubes were grown in situ on cerium-doped foam carbon by chemical vapor deposition to obtain pretreated foam carbon.

[0108] In step (A), the mass ratio of cerium nitrate hexahydrate to sucrose is 0.35:1.

[0109] In step (A), the heating and mixing conditions are: heating and mixing at 155°C for 6 minutes.

[0110] In step (A), the drying temperature is 178°C and the drying time is 9 minutes.

[0111] In step (B), the specific conditions for chemical vapor deposition are as follows: 0.08 mg / mL ferrocene xylene solution is used as the catalyst; acetylene is used as the carbon source, and argon and hydrogen in a volume ratio of 3:1 are used as the protective atmosphere; the temperature is increased to 850℃ at 11℃ / min; and the growth time is 18 minutes.

[0112] In step (1), the transition metal inorganic salt is zinc chloride.

[0113] In step (1), the boron-containing small molecule is sodium borate.

[0114] In step (2), the magnetic field strength is 60mT, the ultrasonic frequency is 30kHz, the power is 850W, and the processing time is 2 hours.

[0115] In step (2), the settling time is 35 minutes.

[0116] In step (3), the calcination conditions are: under a nitrogen atmosphere, the temperature is increased to 750°C at 18°C / min and calcined for 7 hours.

[0117] In step (3), the calcined doped porous material is naturally cooled to room temperature (25°C) and then immersed in 1-butyl-3-methylimidazolium hexafluoroantimonate and 1-butyl-3-methylimidazolium dicyandiamide salt for 55 minutes. The mass ratio of the calcined doped porous material, 1-butyl-3-methylimidazolium hexafluoroantimonate and 1-butyl-3-methylimidazolium dicyandiamide salt is 1:2.5:2.5.

[0118] In step (3), the post-processing includes: filtering to obtain the solid, washing with deionized water, and drying.

[0119] Example 6:

[0120] A method for preparing a supported catalyst, comprising the following specific steps:

[0121] (1) First, dissolve the transition metal inorganic salt and boron-containing small molecules in water to obtain a premixed solution;

[0122] (2) Then the carrier is added to the premixed liquid, ultrasonically oscillated under magnetic field conditions, allowed to stand, and solid-liquid separation is performed to obtain the doped porous material.

[0123] (3) Finally, the doped porous material is calcined, impregnated with 1-benzyl-2,3-dimethylimidazolium hexafluoroantimonate and 1-butyl-3-methylimidazolium dicyandiamide salt, and then post-treated to obtain the supported catalyst.

[0124] The mass ratio of transition metal inorganic salt, boron-containing small molecule, water, and carrier is 4:2:125:100.

[0125] The carrier is modified foamed carbon, which is prepared by the following method:

[0126] (A) First, cerium nitrate hexahydrate is mixed evenly with sucrose, heated and mixed, and then quickly transferred to a forced-air drying oven to dry, thus obtaining cerium-doped foam carbon;

[0127] (B) Then carbon nanotubes were grown in situ on cerium-doped foam carbon by chemical vapor deposition to obtain pretreated foam carbon;

[0128] (C) Finally, nano-titanium dioxide is electrophoretically deposited on the surface of the pretreated foam carbon to obtain the final product.

[0129] In step (A), the mass ratio of cerium nitrate hexahydrate to sucrose is 0.35:1.

[0130] In step (A), the heating and mixing conditions are: heating and mixing at 155°C for 6 minutes.

[0131] In step (A), the drying temperature is 178°C and the drying time is 9 minutes.

[0132] In step (B), the specific conditions for chemical vapor deposition are as follows: 0.08 mg / mL ferrocene xylene solution is used as the catalyst; acetylene is used as the carbon source, and argon and hydrogen in a volume ratio of 3:1 are used as the protective atmosphere; the temperature is increased to 850℃ at 11℃ / min; and the growth time is 18 minutes.

[0133] The specific method of step (C) is as follows: pretreated foamed carbon is used as the negative electrode, and graphite is used as the positive electrode, and electrophoretic deposition is performed in a suspension; the suspension is obtained by stirring and dispersing magnesium chloride hexahydrate and nano-titanium dioxide in anhydrous ethanol; the electrophoretic deposition conditions are: current density 18 mA / cm². 2 The deposition time was 4 minutes. The mass ratio of magnesium chloride hexahydrate, nano titanium dioxide, and anhydrous ethanol was 0.1:1.3:35.

[0134] In step (1), the transition metal inorganic salt is zinc chloride.

[0135] In step (1), the boron-containing small molecule is sodium borate.

[0136] In step (2), the magnetic field strength is 60mT, the ultrasonic frequency is 30kHz, the power is 850W, and the processing time is 2 hours.

[0137] In step (2), the settling time is 35 minutes.

[0138] In step (3), the calcination conditions are: under a nitrogen atmosphere, the temperature is increased to 750°C at 18°C / min and calcined for 7 hours.

[0139] In step (3), the calcined doped porous material is naturally cooled to room temperature (25°C) and then immersed in 1-butyl-3-methylimidazolium hexafluoroantimonate and 1-butyl-3-methylimidazolium dicyandiamide salt for 55 minutes. The mass ratio of the calcined doped porous material, 1-butyl-3-methylimidazolium hexafluoroantimonate and 1-butyl-3-methylimidazolium dicyandiamide salt is 1:2.5:2.5.

[0140] In step (3), the post-processing includes: filtering to obtain the solid, washing with deionized water, and drying.

[0141] Comparative Example 1

[0142] Transition metal inorganic salts are omitted;

[0143] The rest is the same as in Example 1.

[0144] Comparative Example 2

[0145] Boron-containing small molecules are omitted;

[0146] The rest is the same as in Example 1.

[0147] Comparative Example 3

[0148] The magnetic field condition is omitted in step (2);

[0149] The rest is the same as in Example 1.

[0150] Comparative Example 4

[0151] 1-Benzyl-2,3-dimethylimidazolium hexafluoroantimonate was omitted during impregnation;

[0152] The rest is the same as in Example 1.

[0153] Comparative Example 5

[0154] Omit the 1-butyl-3-methylimidazolium dicyandiamide salt impregnation during immersion;

[0155] The rest is the same as in Example 1.

[0156] Test case

[0157] The supported catalysts obtained in Examples 1-6 or Comparative Examples 1-5 were used for the synthesis of phenyldicarboxylic acid chloride, specifically using Method 1 and Method 2.

[0158] Method 1:

[0159] A method for synthesizing phenyldicarboxylic acid chloride involves mixing 0.1 kg of terephthalic acid (PTA), 0.35 kg of thionyl chloride (SOCl2), and 0.9 g of supported catalyst evenly, heating the mixture to 75 °C at 11 °C / min, maintaining the temperature for 3 hours, and then performing post-treatment to obtain the phenyldicarboxylic acid chloride.

[0160] Post-treatment includes: sequentially absorbing the reaction tail gas with water and 30% sodium hydroxide solution, distilling to recover unreacted thionyl chloride, filtering to recover the supported catalyst, and distilling the filtrate under reduced pressure to obtain phenyldicarboxylic acid chloride (TPC).

[0161] The vacuum degree of the reduced pressure distillation is 350 Pa, and the fraction receiving temperature is 110-120℃.

[0162] Method 2:

[0163] A method for synthesizing phenyldicarboxylic acid chloride involves mixing 10 kg of terephthalic acid (PTA), 35 kg of thionyl chloride (SOCl2), and 90 g of supported catalyst evenly, heating the mixture to 75 °C at 11 °C / min, maintaining the temperature for 3 hours, and then performing post-treatment to obtain the phenyldicarboxylic acid chloride.

[0164] Post-treatment includes: sequentially absorbing the reaction tail gas with water and 30% sodium hydroxide solution, distilling to recover unreacted thionyl chloride, filtering to recover the supported catalyst, and distilling the filtrate under reduced pressure to obtain phenyldicarboxylic acid chloride (TPC).

[0165] The vacuum degree of the reduced pressure distillation is 350 Pa, and the fraction receiving temperature is 110-120℃.

[0166] The yield and purity of terephthaloyl chloride were statistically analyzed (by liquid chromatography), and the results are shown in Table 1.

[0167] Table 1

[0168]

[0169] As shown in Table 1, the supported catalysts of Examples 1-6 can be used for the synthesis of terephthaloyl chloride, achieving high yields and high purity at lower temperatures and shorter times. After scale-up of Method 2, the product yield and purity were not significantly affected. Specifically, the support in Example 3 was carbon foam, in Example 4 it was cerium-doped carbon foam, in Example 5 it was pretreated carbon foam, and in Example 6 it was modified carbon foam, further improving product yield and purity. After scale-up of Method 2, the product yield and purity were almost unaffected.

[0170] Comparative Example 1 omitted the transition metal inorganic salt, Comparative Example 2 omitted the boron-containing small molecule, Comparative Example 3 omitted the magnetic field condition in step (2), Comparative Example 4 omitted 1-benzyl-2,3-dimethylimidazolium hexafluoroantimonate during impregnation, and Comparative Example 5 omitted 1-butyl-3-methylimidazolium dicyandiamide salt impregnation. The product yield and purity were significantly lower in all cases, indicating that the support of this invention, along with the transition metal inorganic salt and boron-containing small molecule components, synergistically improved the catalytic effect, promoted the reaction, and increased the product yield and purity. Comparative Examples 4 and 5 showed a significant scale-up effect, indicating that the introduction of ionic liquid improved the surface properties of the supported catalyst and maintained a good reaction microenvironment after scale-up production, thus promoting the reaction.

[0171] Finally, it should be noted that the above preferred embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit it. Although the present invention has been described in detail through the above preferred embodiments, those skilled in the art should understand that various changes can be made to it in form and detail without departing from the scope defined by the claims of the present invention.

Claims

1. A method for preparing a supported catalyst for the synthesis of phenyldicarboxylic acid chloride, characterized in that, The specific steps are as follows: (1) First, dissolve the transition metal inorganic salt and boron-containing small molecules in water to obtain a premixed solution; (2) Then the carrier is added to the premixed liquid, ultrasonically oscillated under magnetic field conditions, allowed to stand, and solid-liquid separation is performed to obtain the doped porous material. (3) Finally, the doped porous material is calcined, impregnated with 1-benzyl-2,3-dimethylimidazolium hexafluoroantimonate and 1-butyl-3-methylimidazolium dicyandiamide salt, and then post-treated to obtain the supported catalyst described above. The carrier is selected from one or more of activated alumina, molecular sieve, diatomaceous earth, organobentonite, carbon foam, or modified carbon foam. The mass ratio of transition metal inorganic salt, boron-containing small molecule, water, and carrier is 1–5: 1–3: 120–130: 100; The modified foamed carbon is prepared by the following method: (A) First, cerium nitrate hexahydrate is mixed evenly with sucrose, heated and mixed, and then quickly transferred to a forced-air drying oven to dry, thus obtaining cerium-doped foam carbon; (B) Then carbon nanotubes were grown in situ on cerium-doped foam carbon by chemical vapor deposition to obtain pretreated foam carbon; (C) Finally, nano-titanium dioxide is electrophoretically deposited on the surface of the pretreated foamed carbon to obtain the final product; In step (3), the calcination conditions are: under a nitrogen atmosphere, the temperature is increased to 700-800℃ at a rate of 15-20℃ / min, and the temperature is maintained for calcination for 6-8 hours; The calcined doped porous material was naturally cooled to room temperature and then immersed in 1-butyl-3-methylimidazolium hexafluoroantimonate and 1-butyl-3-methylimidazolium dicyandiamide salt for 50-60 minutes. The mass ratio of the calcined doped porous material, 1-butyl-3-methylimidazolium hexafluoroantimonate and 1-butyl-3-methylimidazolium dicyandiamide salt was 1:2-3:2-3. The transition metal inorganic salt is selected from one or more inorganic salts of iron, cobalt, nickel, copper or zinc, and the anion of the inorganic salt is any one of nitrate, sulfate or chloride ions. The boron-containing small molecule is selected from any one of boric acid, sodium borate, phenylboronic acid or sodium borohydride; The magnetic field strength is 50–70 mT, the ultrasonic frequency is 25–35 kHz, the power is 800–900 W, and the processing time is 2–3 hours. Let it stand for 30 to 40 minutes.

2. A supported catalyst for the synthesis of phenyldicarboxylic acid chloride, characterized in that, It is obtained by the preparation method described in claim 1.

3. The application of the supported catalyst according to claim 2 in the synthesis of phenyldicarboxylic acid chloride, characterized in that, Terephthalic acid, thionyl chloride, and the supported catalyst described in claim 2 are mixed uniformly at a mass ratio of 1:3-4:0.008-0.01, heated to 70-80°C at 10-12°C / min, and kept at this temperature for 3-4 hours. After post-treatment, the phenyldicarboxylic acid chloride is obtained.

4. The application according to claim 3, characterized in that, Post-processing includes: The reaction tail gas was absorbed sequentially by water and 30% sodium hydroxide solution. Unreacted thionyl chloride was recovered by distillation, the supported catalyst was recovered by filtration, and phenyldicarboxylic acid chloride was obtained by vacuum distillation of the filtrate.

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