Conjugated microporous polyaniline material for adsorbing BPA as well as preparation method and application of conjugated microporous polyaniline material

Abstract

The invention discloses a conjugated microporous polyaniline material for adsorbing BPA and a preparation method and application of the conjugated microporous polyaniline material. 1, 3, 5-tri (4-bromophenyl) benzene, 2, 4, 6-tri (4-aminophenyl)-1, 3, 5-tri (4-bromophenyl) benzene and 2, 4, 6-tri (4-aminophenyl)-1, 3, 5-tri (4-bromophenyl)-1, 3, 5-tri (4-bromophenyl The preparation method comprises the following steps: carrying out a reaction on 1, 3, 5-triazine, sodium fluoride, sodium tert-butoxide, 2-dicyclohexylphosphorus-2 ', 4', 6 '-triisopropyl biphenyl and bis (dibenzylideneacetone) palladium in a solvent to obtain the conjugated microporous polyaniline material for adsorbing BPA. 1, 3, 5-tri (4-bromophenyl) benzene with a three-dimensional symmetrical structure is used as a core construction unit, N-rich 2, 4, 6-tri (4-aminophenyl)-1, 3, 5-triazine is used as a linker to synthesize the conjugated microporous polyaniline material with a large specific surface area, rich microporous structures and strong hydrophobicity, the adsorption capacity of BPA in a water body reaches 2859 mg.g <-1 > at the temperature of 25 DEG C, and the adsorption capacity of BPA in the water body reaches 2,500 mg.g <-1 >. The adsorption capacity is large and the cycle performance is good.

Description

Technical Field

[0001] The present invention belongs to the technical field of wastewater treatment, and specifically relates to a conjugated microporous polyaniline material for adsorbing BPA, its preparation method and application. Background Art

[0002] Bisphenol A (BPA), also known as 4,4'-(1-methylethylidene) diphenol, is a phenolic endocrine disruptor and is considered one of the most common emerging pollutants in the environment. Its main applications are as common industrial chemicals used in the production of polycarbonate plastics such as baby bottles, toys, thermal receipts, medical devices, and electronic devices. It is expected that the global BPA market size will increase from 7.49 million tons in 2023 to 10.13 million tons in 2028. Due to its widespread presence, BPA can penetrate into the water environment through various channels, including release during manufacturing processes, incomplete removal during wastewater treatment, leakage from landfills, and aging of BPA-containing materials. Once BPA enters the water, it may contaminate groundwater, surface water, and spread through the water cycle, leading to wide distribution and potentially entering the food chain, affecting wildlife and humans. Bisphenol A has been proven to have various negative effects on humans, including endocrine system disorders, cancer, and thyroid hormones. It has been reported that exposure to BPA in children and infants can have health effects on their brains and prostates. Other negative effects include cancer, infertility, low sperm count, headache, dizziness, etc. Therefore, the removal of BPA has always been a serious issue of concern to researchers.

[0003] Currently, various methods for removing BPA have been explored, such as ozonation, nanofiltration, reverse osmosis, etc. However, the adsorption method has become one of the most popular methods due to its low cost, excellent effect, and no harmful by-products. Currently, various types of adsorbents have been used for dye adsorption, and carbon materials, as traditional and the most abundant adsorbents, are widely used. Although they have advantages such as high specific surface area and well-developed pore structure, they have problems of low adsorption capacity and poor regeneration ability. Summary of the Invention

[0004] Aiming at the deficiencies of low adsorption capacity and poor regeneration ability of carbon materials in the prior art, the purpose of the present invention is to provide a conjugated microporous polyaniline material for adsorbing BPA, its preparation method and application. This conjugated microporous polyaniline material has a high adsorption capacity, good adsorption performance and adsorption stability for BPA, and strong regeneration ability.

[0005] To achieve the above purpose, the present invention adopts the following technical solutions to implement:

[0006] A preparation method of a conjugated microporous polyaniline material for adsorbing BPA, comprising the following steps:

[0007] 1,3,5-Tris(4-bromophenyl)benzene, 2,4,6-tris(4-aminophenyl)-1,3,5-triazine, sodium fluoride, sodium tert-butoxide, 2-dicyclohexylphosphino-2',4',6'-triisopropylbiphenyl and bis(dibenzylideneacetone)palladium are reacted in a solvent to obtain a conjugated microporous polyaniline material for adsorbing BPA.

[0008] Further, the molar ratio of 1,3,5-tris(4-bromophenyl)benzene to 2,4,6-tris(4-aminophenyl)-1,3,5-triazine is 1.5 mmol: 0.5 - 1.5 mmol.

[0009] Further, the molar ratio of 1,3,5-tris(4-bromophenyl)benzene, sodium fluoride, sodium tert-butoxide, 2-dicyclohexylphosphino-2',4',6'-triisopropylbiphenyl and bis(dibenzylideneacetone)palladium is 1.5 mmol: 0.5 - 1.5 mmol: 5 - 15 mmol: 0.1 - 0.2 mmol: 0.1 - 0.2 mmol.

[0010] Further, the dosage ratio of 1,3,5-tris(4-bromophenyl)benzene to the solvent is 1.5 mmol: 50 - 150 mL.

[0011] Further, the solvent is tetrahydrofuran.

[0012] Further, 1,3,5-tris(4-bromophenyl)benzene, 2,4,6-tris(4-aminophenyl)-1,3,5-triazine, sodium fluoride, sodium tert-butoxide, 2-dicyclohexylphosphino-2',4',6'-triisopropylbiphenyl and bis(dibenzylideneacetone)palladium are reacted in a solvent. The specific process is as follows: The solvent is added to 1,3,5-tris(4-bromophenyl)benzene, 2,4,6-tris(4-aminophenyl)-1,3,5-triazine, sodium fluoride, sodium tert-butoxide, 2-dicyclohexylphosphino-2',4',6'-triisopropylbiphenyl and bis(dibenzylideneacetone)palladium, and after stirring evenly, the reaction is carried out.

[0013] Further, the adding speed of the solvent is 10 mL / min.

[0014] Further, the reaction temperature is 50 - 70 °C and the time is 24 - 60 h; the reaction is carried out under a nitrogen atmosphere.

[0015] A conjugated microporous polyaniline material for adsorbing BPA.

[0016] An application of a conjugated microporous polyaniline material for adsorbing BPA in adsorbing BPA.

[0017] Compared with the prior art, the present invention has the following beneficial effects:

[0018] In this invention, 1,3,5-tris(4-bromophenyl)benzene with a three-dimensional symmetric structure is used as the core building unit, and 2,4,6-tris(4-aminophenyl)-1,3,5-triazine rich in N is used as the linker to synthesize a conjugated microporous polyaniline material with a large specific surface area, a rich microporous structure, and strong hydrophobicity. At 25 °C, the adsorption capacity for BPA in water reaches 2859 mg·g -1 , which is the largest adsorption capacity in the existing research. The conjugated microporous polyaniline material prepared in this invention has the advantage of a large adsorption capacity and can efficiently remove BPA in water. Through adsorption experiments under different pH conditions, it is found that the adsorption of BPA by the conjugated microporous polyaniline material has no obvious pH dependence; at the same time, through multiple cyclic adsorption experiments, it is found that the conjugated microporous polyaniline material has good adsorption stability, and the removal rate of BPA still remains above 99% after 10 cycles, improving the effective recovery of BPA and having considerable potential for practical applications. Description of the Drawings

[0019] Figure 1 XRD pattern of the conjugated microporous polyaniline material prepared in Example 1 of this invention;

[0020] Figure 2 FTIR spectra of the conjugated microporous polyaniline material prepared in Example 1 of this invention, as well as 1,3,5-tris(4-bromophenyl)benzene and 2,4,6-tris(4-aminophenyl)-1,3,5-triazine;

[0021] Figure 3 SEM image of the conjugated microporous polyaniline material prepared in Example 1 of this invention;

[0022] Figure 4 TG diagram of the conjugated microporous polyaniline material prepared in Example 1 of this invention;

[0023] Figure 5 Contact angle measurement diagram of the conjugated microporous polyaniline material prepared in Example 1 of this invention;

[0024] Figure 6 Nitrogen adsorption-desorption isotherm diagram of the conjugated microporous polyaniline material prepared in Example 1 of this invention;

[0025] Figure 7 Pore size distribution diagram of the conjugated microporous polyaniline material prepared in Example 1 of this invention;

[0026] Figure 8 Removal rate change curve of BPA by the conjugated microporous polyaniline material prepared in Example 1 of this invention under different pH conditions;

[0027] Figure 9Isothermal adsorption Langmuir and Freundlich model fitting curves of the conjugated microporous polyaniline materials prepared in Examples 1 to 3 of the present invention for BPA in water;

[0028] Figure 10 Removal rate change curve of the conjugated microporous polyaniline material prepared in Example 1 of the present invention for BPA under different cycle numbers. Detailed implementation manners

[0029] To facilitate the understanding of the present invention, the present invention will be described more comprehensively below with reference to the relevant drawings. The preferred embodiments of the present invention are shown in the drawings. However, the present invention can be implemented in many different forms and is not limited to the embodiments described herein. On the contrary, these embodiments are provided to make the disclosure of the present invention more thorough and comprehensive.

[0030] Conjugated microporous polymers have excellent properties such as high stability and large specific surface area. In particular, their π-conjugated skeletons can form π-π interactions with organic pollutants, making them one of the best candidates for adsorbing organic pollutants. Based on this, the present invention provides an adsorbent material for BPA with a large adsorption capacity and strong stability.

[0031] A preparation method of a conjugated microporous polyaniline material for adsorbing BPA according to the present invention includes the following steps:

[0032] Step 1: Place 1.5 mmol of 1,3,5-tris(4-bromophenyl)benzene (as the core unit), 0.5 - 1.5 mmol of 2,4,6-tris(4-aminophenyl)-1,3,5-triazine (as the linker), 0.5 - 1.5 mmol of sodium fluoride (NaF), 5 - 15 mmol of sodium tert-butoxide (NaOtBu), 0.1 - 0.2 mmol of 2-dicyclohexylphosphino-2',4',6'-triisopropylbiphenyl (XPhos), and 0.1 - 0.2 mmol of bis(dibenzylideneacetone)palladium (Pd(dba)2) in a Schlenk flask with a side arm;

[0033] Step 2: First, evacuate and fill with nitrogen, repeat 3 times, and then under a nitrogen atmosphere, add 50 - 150 mL of tetrahydrofuran to the reaction flask at a rate of 10 mL / min. First, stir at a stirring speed of 300 rpm at room temperature (25°C) for 0.5 - 2 h, then adjust the reaction temperature to 50 - 70°C, and react at 400 rpm for 24 - 60 h. After the reaction is completed, a suspension is obtained, which is filtered, washed (washed with chloroform, ethanol, and pure water in sequence), and dried in a vacuum oven at 80°C for 24 h to obtain a conjugated microporous polyaniline material, denoted as CMPA-PN.

[0034] The reaction formula is:

[0035]

[0036] In the present invention, it is a three-dimensional covalent cross-linking reaction system based on Buchwald-Hartwig coupling, and the functions of each raw material are as follows:

[0037] (1) Core unit: 1,3,5-tris(4-bromophenyl)benzene

[0038] ① Function:

[0039] Three-dimensional cross-linking center: Three para-bromine atoms (Ar-Br) serve as electrophilic sites and form covalent bonds with the amino groups (-NH2) of the linker through C-N coupling reactions.

[0040] Rigid framework: The planarity and symmetry of the benzene ring ensure the stability and uniformity of the three-dimensional network structure and prevent pore collapse.

[0041] ② Role in the reaction mechanism:

[0042] The bromine atoms undergo oxidative addition under palladium catalysis to generate arylpalladium intermediates, providing active sites for subsequent coupling.

[0043] (2) Linker: 2,4,6-tris(4-aminophenyl)-1,3,5-triazine

[0044] ① Function:

[0045] Nucleophile: The amino group (-NH2) acts as a strong nucleophilic group and attacks the palladium-activated bromine atom to form a C-N bond.

[0046] Nitrogen-rich adsorption sites: The triazine ring (C3N3) and aniline units provide sites for hydrogen bonding (with the -OH of BPA) and π-π stacking (with the aromatic ring of BPA).

[0047] Conjugation extension: The conjugation of aniline with the triazine ring enhances the hydrophobicity and chemical stability of the material.

[0048] ② Role in the reaction mechanism:

[0049] The amino group forms a cross-linked network with the bromine atoms of the core through nucleophilic substitution or palladium-catalyzed coupling.

[0050] (3) Catalyst system: Pd(dba)2 / XPhos

[0051] ① Bis(dibenzylideneacetone)palladium (Pd(dba)2):

[0052] As a palladium source, it provides zero-valent palladium (Pd 0 ), and catalyzes the coupling reaction between bromine atoms and amino groups.

[0053] Undergoes oxidative addition (Pd 0 →Pd 2+ ) and reductive elimination (Pd 2+ →Pd 0 ) cycles in the reaction.

[0054] ② XPhos ligand:

[0055] As a bulky phosphine ligand, it stabilizes the palladium intermediate, improves the selectivity and activity of the catalyst, and especially prevents side reactions in reactions with large steric hindrance.

[0056] Enhances the electron density of palladium and promotes the activation of aryl bromides.

[0057] (4) Base system: NaF and NaOtBu

[0058] ① Sodium fluoride (NaF):

[0059] As a mild base, it neutralizes the HBr generated in the reaction and drives the reaction equilibrium towards the product direction.

[0060] Some fluoride ions may assist the palladium catalytic cycle through weak coordination.

[0061] ② Sodium tert-butoxide (NaOtBu):

[0062] A strong base that accelerates the deprotonation step (such as the elimination of HBr after the attack of an amino group) and promotes the efficient progress of the coupling reaction.

[0063] Cooperates with NaF to regulate the alkalinity of the reaction system and avoid side reactions caused by a single strong base (such as amidation or excessive dehalogenation).

[0064] (5) Solvent: Tetrahydrofuran (THF)

[0065] Solubility: A polar aprotic solvent that can dissolve aromatic core units, linkers, and catalyst systems.

[0066] Stability: Inert to the palladium catalyst, avoiding side reactions involving the solvent.

[0067] Reaction temperature adaptability: Moderate boiling point (66 °C), suitable for long-term reactions under heating conditions.

[0068] Step-by-step analysis of the reaction mechanism:

[0069] (1) Catalyst activation:

[0070] Pd(dba)2 generates the active palladium species Pd0(XPhos) in the presence of the XPhos ligand.

[0071] (2) Oxidative addition:

[0072] The Ar-Br of the core unit undergoes oxidative addition with Pd0 to form an Ar-Pd 2+ -Br intermediate.

[0073] (3) Ligand exchange and amine coordination:

[0074] The amino group (-NH2) of the linker replaces the bromine ligand to generate an Ar-Pd 2+ -NH-Ar intermediate.

[0075] (4) Deprotonation and reductive elimination:

[0076] Under the action of NaOtBu, the proton of the amino group is removed, and then reductive elimination occurs to form a C-N bond and release Pd 0 , completing the catalytic cycle.

[0077] (5) Three-dimensional network formation:

[0078] The three bromine atoms of each core unit react with the amino groups of three linkers, and symmetry-driven periodic crosslinking forms a three-dimensional conjugated framework with micropores.

[0079] The conjugated microporous polyaniline material for adsorbing BPA prepared by the method has an adsorption capacity of 2859 mg·g for BPA in water at 25 °C -1 .

[0080] Through the unique combination design of the core unit and the linker, the present invention realizes the efficient adsorption of BPA, and its innovation is reflected in the following aspects:

[0081] 1. Selection of the core unit 1,3,5-tris(4-bromophenyl)benzene: Three-dimensional symmetry and rigid framework

[0082] (1) Three-dimensional symmetry: The three para-bromophenyl groups are symmetrically distributed at 120° around the benzene ring, forming a rigid three-dimensional crosslinked network, avoiding pore collapse and ensuring a stable microporous structure (pore diameter 1.88 nm).

[0083] (2) High reactivity of bromine atoms: As electrophilic sites, they form covalent bonds with the amino groups of the linker through Buchwald-Hartwig coupling, promoting periodic crosslinking and generating uniform micropores (BET specific surface area 912 m 2 / g).

[0084] (3) Enhanced hydrophobicity: The conjugated framework of the benzene ring provides a strong hydrophobic surface (contact angle 139.5°), reducing competitive adsorption of water molecules and preferentially capturing hydrophobic BPA (logP = 3.4).

[0085] 2. Design of the linker 2,4,6-tris(4-aminophenyl)-1,3,5-triazine: nitrogen-rich triazine ring and multiple adsorption sites

[0086] (1) Nitrogen-rich property: The triazine ring (C3N3) contains three nitrogen atoms, and the aniline unit provides additional amino groups, forming multiple adsorption sites (nitrogen content > 8 wt%).

[0087] (2) Synergistic mechanism:

[0088] ① π-π stacking: The triazine ring and the benzene ring of BPA enhance the adsorption energy through the overlap of π electron clouds.

[0089] ② Hydrogen bonding: The nitrogen of the triazine ring forms hydrogen bonds with the hydroxyl group (-OH) of BPA.

[0090] ③ Hydrophobic matching: The hydrophobic skeleton of the linker matches the hydrophobic property of BPA, reducing the solvation effect.

[0091] The following are specific examples.

[0092] Example 1

[0093] Step 1: Place 1.5 mmol of 1,3,5-tris(4-bromophenyl)benzene, 1.0 mmol of 2,4,6-tris(4-aminophenyl)-1,3,5-triazine, 1.0 mmol of sodium fluoride, 10 mmol of sodium tert-butoxide, 0.15 mmol of 2-dicyclohexylphosphino-2',4',6'-triisopropylbiphenyl, and 0.15 mmol of bis(dibenzylideneacetone)palladium(0) in a Schlenk flask with a side arm;

[0094] Step 2: First, evacuate and fill with nitrogen, repeat 3 times, and then under a nitrogen atmosphere, add 100 mL of tetrahydrofuran to the reaction flask at a rate of 10 mL / min. First, stir at a stirring speed of 300 rpm at room temperature for 1 h, then adjust the reaction temperature to 65 °C at 400 rpm and react for 40 h. After the reaction is completed, a suspension is obtained. Filter successively and wash with chloroform, ethanol, and pure water, and dry in a vacuum oven at 80 °C for 24 h to obtain a conjugated microporous polyaniline material, denoted as CMPA-PN.

[0095] Analyze the crystallinity of the material using a Bruker D8 ADVANCE X-ray diffractometer from Germany. The test conditions are Cu / Kα radiation method, voltage 40 kV, current 40 mA, scanning range (2θ) of 10 - 80°, and scanning speed of 10 °·min -1 . The results are as Figure 1 shown. The XRD pattern shows a broad hump peak, indicating that the material is mainly amorphous.

[0096] The molecular vibration information of the material was analyzed using a Bruker Tensor 37 Fourier transform infrared spectrometer. The potassium bromide tablet method was used, and the spectral range for testing was 400 - 4000 cm -1 , and the number of scans was 64. The results are as Figure 2 shown. The characteristic C - Br peak of the core subunit 1,3,5 - tris(4 - bromophenyl)benzene originally at 1072 cm -1 disappeared in the synthesized CMPA - PN, and the - NH2 - doublet in the 3300 - 3500 cm -1 region of the linker 2,4,6 - tris(4 - aminophenyl)-1,3,5 - triazine changed to a single - peak of - NH - after synthesis, indicating the successful synthesis of CMPA - PN. After synthesis, CMPA - PN still retained the triazine ring structure in the linker 2,4,6 - tris(4 - aminophenyl)-1,3,5 - triazine within the range of 1500 - 1600 cm -1 . This indicates that during the synthesis process, the rigid triazine skeleton was not damaged during the polymerization process, which is crucial for the final properties of the material. The presence of the triazine ring not only provides additional chemical stability to the material but may also endow it with unique physical and chemical properties.

[0097] The surface and structural characteristics of the material were visually demonstrated using a GeminiSEM 500 scanning electron microscope from Carl Zeiss (Shanghai), China. The results are as Figure 3 shown. CMPA - PN presented a relatively loose network structure, with a relatively rough surface and many uneven structures, indicating that there are many pores or irregular particle accumulations on its surface. The particle size distribution was relatively uniform, without obvious agglomeration, but there were certain voids between the particles, which helps to increase the specific surface area of the material and thus enhance its adsorption performance.

[0098] The thermal stability of the material was tested using a DTG - 60 differential thermal - thermogravimetric synchronous analyzer from Shimadzu, China. The test conditions were a nitrogen atmosphere, a heating rate of 10℃·min -1 , heating up to 800℃ and holding for 1 min. The results are as Figure 4 shown. The weight retention rate of CMPA - PN at 800℃ was 72.84%, indicating its good thermal stability.

[0099] The hydrophilicity of the material was tested using a DSA100S optical contact angle measuring instrument from Krüss, Germany. The test measurement range was 0 - 180°, and the resolution was 0.01°. The results are as Figure 5As shown, the contact angle of CMPA-PN is 139.5°, indicating that CMPA-PN has strong hydrophobicity. BPA is an organic compound with certain hydrophobicity. When the material surface has strong hydrophobicity, the material surface and BPA molecules can bind through hydrophobic interaction. This interaction is due to the tendency of hydrophobic groups to aggregate together to reduce the contact area with water, thereby reducing the free energy of the system. The surface of a material with strong hydrophobicity can provide more hydrophobic sites, enhancing the interaction with BPA molecules and thus improving the adsorption capacity for BPA.

[0100] The nitrogen adsorption / desorption curves of the materials were tested using an SSA-4200 full-automatic specific surface area and pore size analyzer. Before testing, the samples need to be pretreated by heating the samples at 80 °C for 4 h under vacuum conditions to remove impurities on the material surface. The specific surface area was calculated according to the Brunauer-Emmett-Teller (BET) model, and the pore volume and pore size distribution were calculated according to Barrett-Joyner-Halenda (BJH). The results are as Figure 6 and Figure 7 shown. The specific surface area of CMPA-PN reached 912 m 2 ·g -1 , and the pore size was mainly distributed at 1.88 nm.

[0101] First, the pH of the BPA solution was adjusted to 2.0 - 10.0 with 1 mol·L -1 sodium hydroxide and hydrochloric acid solutions. Then, 1.5 mg of CMPA-PN prepared in Example 1 was added to a glass bottle, and then 30 mL of the BPA solution with the adjusted pH of 0.025 mmol·L -1 was added. The glass bottle was transferred to a magnetic heating stirrer at 25 °C for adsorption. After the reaction, the solution after the reaction was aspirated with a syringe, and the reaction solution sample was filtered through a 0.45 μm polyethersulfone membrane. Then, the remaining BPA concentration in the sample was measured using an HPLC high-performance liquid chromatograph. All experiments were set up with three parallel samples to reduce errors. According to the detection results, a curve of the influence of pH on the BPA removal rate was plotted. The results are as Figure 8 shown. It was found that in the range of pH 2.0 - 9.0, the adsorption of BPA by CMPA-PN has no obvious pH dependence. This pH-independent adsorption behavior highlights the excellent compatibility of CMPAs in removing BPA from water.

[0102] First, 1.5 mg of CMPA-PN prepared in Example 1 was added to a glass bottle, and then 30 mL of BPA solutions with different concentrations in the range of 0.025 mmol·L -1 , 0.05 mmol·L -1 , 0.1 mmol·L-1 、0.25 mmol·L -1 、0.5 mmol·L -1 、0.6 mmol·L -1 、0.8 mmol·L -1 、1.0 mmol·L -1 Transfer the glass bottle to a magnetic heating stirrer at 25 °C for adsorption. After the reaction, use a syringe to draw the reacted solution and filter the reaction solution sample through a 0.45-μm polyethersulfone filter membrane. Then, use an HPLC high-performance liquid chromatograph to measure the remaining BPA concentration in the sample. All experiments are set up with three parallel samples to reduce errors. According to the detection results, an isothermal adsorption curve is drawn. The results are as Figure 9 shown. It is found that the adsorption process of the conjugated microporous polyaniline prepared in Example 1 for BPA conforms to the Freundlich model, indicating that the adsorption process is a multi-layer adsorption. Moreover, under the condition of 25 °C, the adsorption capacity of the 0.05 g·L -1 conjugated microporous polyaniline material is 2859 mg·g -1 .

[0103] See Figure 10 , at [CMPA-PN] = 0.05 g·L -1 ; [BPA] = 0.025 mmol·L -1 , and T = 298 K, the change in the removal rate of BPA in water by the CMPA-PN prepared in Example 1 with the number of adsorption times was measured. It can be seen that the removal rate of CMPA-PN for BPA still remains above 98% after 10 cycles; it can be seen that CMPA-PN has excellent reusability for adsorbing BPA and has good application prospects in the field of water pollution remediation.

[0104] Example 2

[0105] Step 1: Place 1.5 mmol of 1,3,5-tris(4-bromophenyl)benzene, 1.5 mmol of 2,4,6-tris(4-aminophenyl)-1,3,5-triazine, 1.0 mmol of sodium fluoride, 10 mmol of sodium tert-butoxide, 0.15 mmol of 2-dicyclohexylphosphino-2',4',6'-triisopropylbiphenyl, and 0.15 mmol of bis(dibenzylideneacetone)palladium(0) in a Schlenk flask with a side arm.

[0106] Step 2: First, evacuate and then fill with nitrogen. After repeating this process 3 times, under a nitrogen atmosphere, add 100 mL of tetrahydrofuran to the reaction flask at a rate of 10 mL / min. First, stir at a speed of 300 rpm at room temperature for 1 h, then adjust the reaction temperature to 65 °C at 400 rpm and react for 40 h. After the reaction is completed, a suspension is obtained. Filter successively and wash with chloroform, ethanol, and pure water. Dry in a vacuum oven at 80 °C for 24 h to obtain the conjugated microporous polyaniline material.

[0107] First, add 1.5 mg of CMPA-PN prepared in Example 2 to a glass bottle, and then add 30 mL of BPA solutions with different concentrations in the range of 0.025 mmol·L -1 、0.05 mmol·L -1 、0.1 mmol·L -1 、0.25 mmol·L -1 、0.5 mmol·L -1 、0.6 mmol·L -1 、0.8 mmol·L -1 、1.0 mmol·L -1 . Transfer the glass bottle to a magnetic heating stirrer at 25 °C for adsorption. After the reaction is completed, use a syringe to draw the reacted solution and filter the reaction solution sample through a 0.45-μm polyethersulfone membrane. Then, use an HPLC high-performance liquid chromatograph to measure the remaining BPA concentration in the sample. All experiments are set with three parallel samples to reduce errors. Draw an isothermal adsorption curve based on the detection results. The results are as Figure 9 shown. It is found that the adsorption process of the conjugated microporous polyaniline prepared in Example 2 for BPA conforms to the Freundlich model, indicating that the adsorption process is a multi-layer adsorption. Moreover, at 25 °C, the adsorption capacity of the 0.05 g·L -1 conjugated microporous polyaniline material is 2578 mg·g -1 .

[0108] Example 3

[0109] Step 1: Place 1.5 mmol of 1,3,5-tris(4-bromophenyl)benzene, 0.5 mmol of 2,4,6-tris(4-aminophenyl)-1,3,5-triazine, 1.0 mmol of sodium fluoride, 10 mmol of sodium tert-butoxide, 0.15 mmol of 2-dicyclohexylphosphino-2’,4’,6’-triisopropylbiphenyl, and 0.15 mmol of bis(dibenzylideneacetone)palladium(0) in a Schlenk branched reaction flask;

[0110] Step 2: First, evacuate and then fill with nitrogen. After repeating this process 3 times, under a nitrogen atmosphere, add 100 mL of tetrahydrofuran to the reaction flask at a rate of 10 mL / min. First, stir at a speed of 300 rpm at room temperature for 1 h, then adjust the reaction temperature to 65 °C at 400 rpm and react for 40 h. After the reaction is completed, a suspension is obtained. Filter it successively and wash it with chloroform, ethanol, and pure water. Dry it in a vacuum oven at 80 °C for 24 h to obtain the conjugated microporous polyaniline material.

[0111] First, add 1.5 mg of CMPA-PN prepared in Example 3 to a glass bottle, and then add 30 mL of BPA solutions with different concentrations in the range of 0.025 mmol·L -1 、0.05 mmol·L -1 、0.1 mmol·L -1 、0.25 mmol·L -1 、0.5 mmol·L -1 、0.6 mmol·L -1 、0.8 mmol·L -1 、1.0 mmol·L -1 . Transfer the glass bottle to a magnetic heating stirrer at 25 °C for adsorption. After the reaction is completed, use a syringe to aspirate the reaction solution and filter the reaction solution sample through a 0.45 μm polyethersulfone membrane. Then, use an HPLC high-performance liquid chromatograph to measure the remaining BPA concentration in the sample. All experiments are set with three parallel samples to reduce errors. Draw an isothermal adsorption curve based on the detection results. The results are as Figure 9 shown. It is found that the adsorption process of the conjugated microporous polyaniline prepared in Example 3 for BPA conforms to the Freundlich model, indicating that the adsorption process is a multi-layer adsorption. Moreover, under the condition of 25 °C, the adsorption capacity of 0.05 g·L -1 conjugated microporous polyaniline material is 2304 mg·g -1 .

[0112] Example 4

[0113] Step 1: Place 1.5 mmol of 1,3,5-tris(4-bromophenyl)benzene, 0.5 mmol of 2,4,6-tris(4-aminophenyl)-1,3,5-triazine, 0.5 mmol of sodium fluoride, 15 mmol of sodium tert-butoxide, 0.2 mmol of 2-dicyclohexylphosphino-2',4',6'-triisopropylbiphenyl, and 0.2 mmol of bis(dibenzylideneacetone)palladium(0) in a Schlenk branched reaction flask.

[0114] Step 2: First, evacuate and fill with nitrogen. After repeating this 3 times, under a nitrogen atmosphere, add 100 mL of tetrahydrofuran to the reaction flask at a rate of 10 mL / min. First, stir at a speed of 300 rpm at room temperature for 1 h, then adjust the reaction temperature to 60 °C at 400 rpm and react for 60 h. After the reaction is completed, a suspension is obtained. Filter successively and wash with chloroform, ethanol, and pure water. Dry in a vacuum oven at 80 °C for 24 h to obtain the conjugated microporous polyaniline material.

[0115] Example 5

[0116] Step 1: Place 1.5 mmol of 1,3,5-tris(4-bromophenyl)benzene, 1.5 mmol of 2,4,6-tris(4-aminophenyl)-1,3,5-triazine, 1.5 mmol of sodium fluoride, 5 mmol of sodium tert-butoxide, 0.1 mmol of 2-dicyclohexylphosphino-2',4',6'-triisopropylbiphenyl, and 0.1 mmol of bis(dibenzylideneacetone)palladium(0) in a Schlenk flask with a side arm.

[0117] Step 2: First, evacuate and fill with nitrogen. After repeating this 3 times, under a nitrogen atmosphere, add 100 mL of tetrahydrofuran to the reaction flask at a rate of 10 mL / min. First, stir at a speed of 300 rpm at room temperature for 0.5 h, then adjust the reaction temperature to 70 °C at 400 rpm and react for 24 h. After the reaction is completed, a suspension is obtained. Filter successively and wash with chloroform, ethanol, and pure water. Dry in a vacuum oven at 80 °C for 24 h to obtain the conjugated microporous polyaniline material.

[0118] Example 6

[0119] Step 1: Place 1.5 mmol of 1,3,5-tris(4-bromophenyl)benzene, 0.7 mmol of 2,4,6-tris(4-aminophenyl)-1,3,5-triazine, 1.2 mmol of sodium fluoride, 8 mmol of sodium tert-butoxide, 0.15 mmol of 2-dicyclohexylphosphino-2',4',6'-triisopropylbiphenyl, and 0.12 mmol of bis(dibenzylideneacetone)palladium(0) in a Schlenk flask with a side arm.

[0120] Step 2: First, evacuate and fill with nitrogen. After repeating this 3 times, under a nitrogen atmosphere, add 100 mL of tetrahydrofuran to the reaction flask at a rate of 10 mL / min. First, stir at a speed of 300 rpm at room temperature for 2 h, then adjust the reaction temperature to 60 °C at 400 rpm and react for 35 h. After the reaction is completed, a suspension is obtained. Filter successively and wash with chloroform, ethanol, and pure water. Dry in a vacuum oven at 80 °C for 24 h to obtain the conjugated microporous polyaniline material.

[0121] For the comparison between the present invention and the prior art, see Table 1.

[0122] Table 1 Comparison between the Present Invention and the Prior Art

[0123]

[0124] Among them, the prior art is the following literature: Jie Chen, Yubing Wang, Changshen Ye, Wei Lyu, Jinwei Zhu, Wei Yan*, Ting Qiu*. Self-Reducible Conjugated Microporous Polyaniline for Long-Term Selective Cr(VI) Detoxication Driven by Tunable Pore Dimension. ACS Applied Materials & Interfaces 2020, 12, 25, 28681–28691.

[0125] Wang Yubing, Li Shanshan, Wu Xiaoxi, Zhang Jiarui, Feng Jiangtao, Li Mingtao, Zong Shirong, Yan Wei. Nitrogen-Based conjugated microporous polymers for efficient Hg(II) removal from Water: Performance and mechanism[J]. Chemical Engineering Journal,2023,471,144659.

[0126] The above is only an illustration of the best embodiment of the present invention, but it should not be construed as a limitation of the claims. The present invention is not limited to the above embodiments, and its specific structure is allowed to vary. Any changes made within the protection scope of the independent claims of the present invention are within the protection scope of the present invention.

[0127] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those of ordinary skill in the technical field to which the present invention belongs. The terms used in the specification of the present invention are only for the purpose of describing specific embodiments and are not intended to limit the present invention. The term "and / or" used herein includes any and all combinations of one or more of the related listed items.

Claims

1. A preparation method of a conjugated microporous polyaniline material for adsorbing BPA, characterized in that, It includes the following steps: React 1,3,5-tris(4-bromophenyl)benzene, 2,4,6-tris(4-aminophenyl)-1,3,5-triazine, sodium fluoride, sodium tert-butoxide, 2-dicyclohexylphosphino-2',4',6'-triisopropylbiphenyl and bis(dibenzylideneacetone)palladium in a solvent to obtain a conjugated microporous polyaniline material for adsorbing BPA.

2. The preparation method of the conjugated microporous polyaniline material for adsorbing BPA according to claim 1, characterized in that, The molar ratio of 1,3,5-tris(4-bromophenyl)benzene to 2,4,6-tris(4-aminophenyl)-1,3,5-triazine is 1.5 mmol: 0.5 - 1.5 mmol.

3. The preparation method of the conjugated microporous polyaniline material for adsorbing BPA according to claim 1, characterized in that, The molar ratio of 1,3,5-tris(4-bromophenyl)benzene, sodium fluoride, sodium tert-butoxide, 2-dicyclohexylphosphino-2',4',6'-triisopropylbiphenyl and bis(dibenzylideneacetone)palladium is 1.5 mmol: 0.5 - 1.5 mmol: 5 - 15 mmol: 0.1 - 0.2 mmol: 0.1 - 0.2 mmol.

4. The preparation method of the conjugated microporous polyaniline material for adsorbing BPA according to claim 1, characterized in that, The dosage ratio of 1,3,5-tris(4-bromophenyl)benzene to the solvent is 1.5 mmol: 50 - 150 mL.

5. The preparation method of the conjugated microporous polyaniline material for adsorbing BPA according to claim 1, characterized in that The solvent is tetrahydrofuran.

6. The preparation method of the conjugated microporous polyaniline material for adsorbing BPA according to claim 1, characterized in that, React 1,3,5-tris(4-bromophenyl)benzene, 2,4,6-tris(4-aminophenyl)-1,3,5-triazine, sodium fluoride, sodium tert-butoxide, 2-dicyclohexylphosphino-2',4',6'-triisopropylbiphenyl and bis(dibenzylideneacetone)palladium in a solvent. The specific process is: add the solvent to 1,3,5-tris(4-bromophenyl)benzene, 2,4,6-tris(4-aminophenyl)-1,3,5-triazine, sodium fluoride, sodium tert-butoxide, 2-dicyclohexylphosphino-2',4',6'-triisopropylbiphenyl and bis(dibenzylideneacetone)palladium, and stir evenly before reacting.

7. The preparation method of the conjugated microporous polyaniline material for adsorbing BPA according to claim 1, characterized in that The adding speed of the solvent is 10 mL / min.

8. The preparation method of the conjugated microporous polyaniline material for adsorbing BPA according to claim 1, characterized in that, The reaction temperature is 50 - 70 °C and the time is 24 - 60 h; the reaction is carried out under a nitrogen atmosphere.

9. A conjugated microporous polyaniline material for adsorbing BPA prepared by the method according to any one of claims 1 - 8.

10. Application of a conjugated microporous polyaniline material for adsorbing BPA prepared by the method according to any one of claims 1 - 8 in adsorbing BPA.

Images