Organic contaminant water treatment adsorbent material and method of making same

Abstract

The application discloses a kind of organic contaminant water treatment adsorption material and preparation method thereof in the technical field of water treatment material, comprising the following components by weight: material monomer I 2-4 parts, material monomer II 3.5-7 parts, iron trichloride hexahydrate 3.2-6.5 parts, copper nitrate trihydrate 0.36-1.0 parts, zinc nitrate hexahydrate 0.3-1.2 parts.The application breaks through the bottleneck of traditional adsorption material, such as low capacity, slow rate, difficult recovery and poor selectivity, through monomer synthesis, multifunctional COF framework construction, magnetic modification and double-metal active site loading, monomer I provides high-density porphyrin ring, monomer II builds high-porosity COF framework through multi-functional groups, Cu 2+ / Zn 2+ Form strong coordination active sites with porphyrin ring nitrogen atom, and the loading of magnetic nanoparticles makes the active site density and pore structure perfectly matched, avoiding site waste or pore blockage.

Description

Technical Field

[0001] This invention belongs to the field of water treatment materials technology, specifically referring to an adsorption material for treating organic pollutants in water and its preparation method. Background Technology

[0002] With the rapid development of global industrialization and urbanization, and the increasing intensity of agricultural activities, large amounts of organic pollutants are being discharged into aquatic environments, posing a serious threat to ecosystems and human health. These organic pollutants have a wide range of sources and complex compositions, including persistent organic pollutants (POPs), endocrine disruptors (EDCs), polycyclic aromatic hydrocarbons (PAHs), antibiotics, and dyes from industrial wastewater from chemical, pharmaceutical, printing and dyeing, and pesticide industries. They are typically characterized by high toxicity, poor biodegradability, carcinogenic, teratogenic, and mutagenic effects, and a tendency to bioaccumulate and scale up. Even at extremely low concentrations (ng / L or μg / L), they can still pose significant ecological risks and health hazards.

[0003] Currently, water treatment methods for organic pollutants mainly include physical, chemical, and biological methods. Chemical methods, such as advanced oxidation processes (AOPs), non-selectively degrade organic pollutants by generating highly oxidizing hydroxyl radicals (·OH), ultimately mineralizing them into CO2 and H2O. This method is highly efficient and fast, but suffers from high costs, the potential for producing more toxic intermediate products, strict requirements for reaction conditions (pH, temperature), and high energy consumption, making it difficult to widely apply to large-scale wastewater treatment. Biological methods, such as activated sludge processes and biofilm processes, utilize the metabolism of microorganisms to degrade organic matter. They have advantages such as low cost and no secondary pollution, but for many recalcitrant toxic organic pollutants, microbial activity is inhibited, leading to poor treatment effects, long retention times, and large land areas required. Physical methods, such as adsorption, are considered one of the most promising water treatment technologies due to their simple operation, high efficiency, relatively low cost, flexible design, and generally no harmful byproducts. The core of adsorption lies in the performance of the adsorbent material; its development level directly determines the treatment effect and application scope of the technology.

[0004] In the development of adsorption methods, various adsorption materials have been widely studied and applied: Activated carbon: Currently the most widely used commercial adsorbent, it possesses a huge specific surface area, well-developed pore structure, and abundant surface functional groups, exhibiting good adsorption capacity for various organic pollutants. However, activated carbon also has significant drawbacks: Poor adsorption selectivity: It adsorbs a variety of pollutants in water (including natural organic matter), easily leading to pore blockage and reducing the adsorption efficiency of the target pollutant. Difficult regeneration and high losses: Thermal regeneration is energy-intensive, and each regeneration results in a carbon loss of approximately 10-15%; chemical regeneration may generate secondary pollution. Limited mechanical strength: It is easily worn in continuous flow operations. Raw material dependence: It mainly comes from non-renewable resources such as coal and wood. Mineral adsorbents: Such as zeolite, diatomaceous earth, bentonite, kaolin, etc. These materials are abundant and inexpensive. However, their natural forms usually have a small specific surface area and an undesirable pore size distribution, resulting in generally low adsorption capacity for organic pollutants. Furthermore, their strong hydrophilicity is unfavorable for the adsorption of hydrophobic organic matter. Synthetic resins, such as polystyrene and polyacrylate resins, offer advantages such as highly designable pore structure and surface chemistry, good mechanical strength, and ease of regeneration. However, their synthesis process is complex and costly, and some resins are excessively hydrophobic, resulting in poor dispersibility and mass transfer in aqueous phases. Summary of the Invention

[0005] To address the above issues and overcome the shortcomings of existing technologies, this invention provides an adsorbent material for treating organic pollutants in water and its preparation method. This invention overcomes the bottlenecks of traditional adsorbent materials, such as low capacity, slow rate, difficult recovery, and poor selectivity, through a synergistic design involving monomer synthesis, multifunctional COF framework construction, magnetic modification, and bimetallic active site loading. The monomer I (tetraaminophenylporphyrin) provides a high density of porphyrin rings (…). (Accumulation sites), material monomer II (trialdehyde hydroxyl monomer) constructs a high-porosity COF framework through multiple functional groups (aldehyde group, hydroxyl group), and the hydroxyl group enhances the anchoring ability with metal ions, Cu 2+ / Zn 2+ It forms strong coordination active sites with the nitrogen atoms of the porphyrin ring, resulting in specific adsorption of pollutants containing amino or hydroxyl groups (such as tetracycline), achieving both physical retention (COF pores) and chemical coordination (metal ions). The stacking (porphyrin ring) triple adsorption mechanism, along with the loading of magnetic nanoparticles, enables the matching of active site density with pore structure, avoiding site waste or pore blockage.

[0006] To achieve the above objectives, the technical solution adopted by the present invention is as follows: The present invention proposes an organic pollutant water treatment adsorption material, wherein the water treatment adsorption material comprises the following components in parts by weight: 2-4 parts of material monomer I, 3.5-7 parts of material monomer II, 1.2-2.4 parts of ferrous chloride tetrahydrate, 3.2-6.5 parts of ferric chloride hexahydrate, 0.36-1.0 parts of copper nitrate trihydrate, and 0.3-1.2 parts of zinc nitrate hexahydrate;

[0007] Preferably, the preparation method of the material monomer I specifically includes the following steps:

[0008] A1. Place p-acetaminobenzaldehyde and pyrrole in a flask, add anhydrous propionic acid, and after the reaction substrate is completely dissolved, pass flowing nitrogen gas through it. Under light-protected conditions, raise the reaction temperature to carry out the reflux reaction. After the reaction is completed, cool it and transfer the reaction system to an ice-water bath to form a precipitate. Filter the precipitate, collect it, wash it with n-hexane and deionized water in sequence, purify it, and dry it to obtain intermediate product 1.

[0009] Preferably, in step A1, the mass-to-volume ratio of p-acetaminobenzaldehyde to pyrrole is 1 g: 1.7-2.1 mL;

[0010] Preferably, in step A1, the mass concentration of p-acetaminobenzaldehyde in anhydrous propionic acid is 0.02-0.025 g / mL;

[0011] Preferably, in step A1, the reflux reaction temperature is 140-150°C and the reflux reaction time is 8-10 hours.

[0012] A2. Dissolve intermediate product 1 prepared in step A1 in methanol aqueous solution, add NaOH, maintain the reaction temperature to carry out alkaline hydrolysis reaction, after the reaction is completed, cool, add hydrochloric acid aqueous solution to adjust the pH of the reaction system to 3-4, after precipitate is formed, filter, collect the precipitate, purify and dry to obtain material monomer I.

[0013] Preferably, in step A2, the mass ratio of intermediate product 1 to NaOH is 1:0.19-0.24;

[0014] Preferably, in step A2, the reaction temperature of the alkaline hydrolysis reaction is 35-40℃, the reaction time of the alkaline hydrolysis reaction is 1.5-2.5h, and the stirring speed of the alkaline hydrolysis reaction is 400-500rpm.

[0015] Preferably, the preparation method of the material monomer II specifically includes the following steps:

[0016] B1. Mix benzo[1,3]m-dioxacyclopentene-2-carboxylic acid with HBr / acetic acid solution. After mixing evenly, place the reaction system in an ice-water bath and raise the reaction temperature. Slowly add liquid bromine solution through a constant pressure dropping funnel to carry out the bromination reaction. After the addition is complete, continue the reaction. After the reaction is complete, add sodium sulfite aqueous solution and ice water to the reaction system. A precipitate will form. Filter, collect the filter cake, wash and dry to obtain intermediate product 2.

[0017] Preferably, in step B1, the mass-to-volume ratio of the benzo[1,3]-dioxane-2-carboxylic acid to the liquid bromine solution is 0.057-0.074 g / mL;

[0018] Preferably, in step B1, the reaction temperature of the bromination reaction is 120-130°C, and the reaction time of the bromination reaction is 8-12 hours.

[0019] In step B1, benzo[1,3]-dioxacyclopenten-2-carboxylic acid is subjected to a bromination reaction with liquid bromine solution. During the reaction, the electron-donating conjugation effect of the O atom in benzo[1,3]-dioxacyclopenten-2-carboxylic acid significantly increases the electron cloud density of the carbon atoms (C2 and C4 positions) adjacent to O on the five-membered ring, making them active sites for electrophilic substitution. In the acidic environment provided by the HBr / acetic acid solution, Br2 is polarized or reacts with Br... - They combine to form the electrophilic reagent Br. + Thus, an electrophilic substitution reaction occurs, Br + Attacking the electron-rich C2 and C4 positions in the dioxolane yields the dibromo-substituted product (intermediate 2).

[0020] B2. Under a nitrogen atmosphere, the intermediate product 2-phenyl-1,3,5-trimethyltriboronic acid prepared in step B1 was placed in a flask. After the reaction substrate was completely dissolved by adding THF / water solution, tetrakis(triphenylphosphine)palladium catalyst and potassium carbonate were added. After mixing evenly, the reaction temperature was raised to reflux reaction. After the reaction was completed, the mixture was cooled and extracted with ethyl acetate. The organic phase was collected and washed with saturated NaCl water solution. The organic phase was dried with anhydrous sodium sulfate, concentrated under reduced pressure, purified and dried to obtain intermediate product 3.

[0021] Preferably, in step B2, the mass ratio of benzene-1,3,5-trimethyltriboronic acid to intermediate product 2 is 1:0.45-0.60;

[0022] Preferably, in step B2, the amount of tetra(triphenylphosphine)palladium catalyst added is 5%-10% of the mass of benzene-1,3,5-trimethyltriboronic acid;

[0023] Preferably, in step B2, the mass ratio of potassium carbonate to benzene-1,3,5-trimethyltriboronic acid is 1.8-2.3:1;

[0024] Preferably, in step B2, the reflux reaction temperature is 60-70°C and the reflux reaction time is 6-8 hours;

[0025] B3. Under a nitrogen atmosphere, the intermediate product 3 prepared in step B2 and 4-formylphenylboronic acid were placed in a flask. After the reaction substrate was completely dissolved by adding THF / water solution, tetrakis(triphenylphosphine)palladium catalyst and potassium carbonate were added. After mixing evenly, the reaction temperature was raised to reflux reaction. After the reaction was completed, the mixture was cooled and extracted with ethyl acetate. The organic phase was collected and washed with saturated NaCl water solution. After drying the organic phase with anhydrous sodium sulfate, it was concentrated under reduced pressure, purified and dried to obtain material monomer II.

[0026] Preferably, in step B3, the mass ratio of 4-formylphenylboronic acid to intermediate product 3 is 1:1.4-1.6;

[0027] Preferably, in step B3, the amount of tetra(triphenylphosphine)palladium catalyst added is 5%-10% of the mass of 4-formylphenylboronic acid;

[0028] Preferably, in step B3, the mass ratio of potassium carbonate to 4-formylphenylboronic acid is 2.3-2.8:1;

[0029] Preferably, in step B3, the reflux reaction temperature is 80-90°C and the reflux reaction time is 15-20 h;

[0030] In steps B2 and B3, benzene-1,3,5-trimethyltriboronic acid and 4-formylphenylboronic acid are reacted with the dibromo-substituted product prepared in step B1 through a two-step Suzuki coupling reaction. By controlling the reaction amounts of benzene-1,3,5-trimethyltriboronic acid and 4-formylphenylboronic acid, the final material monomer II is obtained.

[0031] This invention also provides a method for preparing an adsorbent material for treating organic pollutants in water, specifically including the following steps:

[0032] S1. Place material monomer I and material monomer II in a flask, add 1,4-dioxane / DMF mixed solvent, mix well, and then introduce flowing nitrogen gas. Under the nitrogen atmosphere, add acetic acid / ethanol solution dropwise using a constant pressure dropping funnel. After the addition is complete, transfer to a polytetrafluoroethylene reaction vessel. Under sealed and light-proof conditions, raise the reaction temperature to carry out the reflux reaction. After the reaction is completed, cool, centrifuge, collect the precipitate, wash with anhydrous DMF and anhydrous ethanol, and dry to obtain the adsorbent material precursor.

[0033] Preferably, in step S1, the volume ratio between the 1,4-dioxane / DMF mixed solvent and the acetic acid / ethanol solution is 10:1-2;

[0034] Preferably, in step S1, the reflux reaction temperature is 120-150°C and the reflux reaction time is 24-36 h;

[0035] S2. Disperse the adsorbent material precursor prepared in step S1 in an ethanol aqueous solution, introduce high-purity flowing nitrogen gas, and add iron salt / ethanol solution dropwise to the reaction system under nitrogen atmosphere. After the addition is complete, maintain room temperature to carry out the coordination reaction. After the reaction is completed, the coordination solution is obtained.

[0036] Preferably, in step S2, the iron salt / ethanol solution is prepared by dissolving ferrous chloride tetrahydrate and ferric chloride hexahydrate in anhydrous ethanol under a nitrogen atmosphere, wherein the mass concentration of ferric chloride hexahydrate in anhydrous ethanol is 0.08-0.135 g / mL.

[0037] Preferably, in step S2, the reaction time of the coordination reaction is 18-24 h, and the stirring speed of the coordination reaction is 300-400 rpm;

[0038] S3. Take the complexation solution prepared in step S2, and add NaOH aqueous solution dropwise to the reaction system under a nitrogen atmosphere using a constant pressure dropping funnel. Keep the pH of the reaction system at 10.5-11. After the addition is complete, raise the reaction temperature to carry out the reflux reaction. After the reaction is completed, cool, centrifuge, collect the precipitate, wash with deionized water, and dry to obtain Fe3O4 modified adsorbent material.

[0039] Preferably, in step S3, the molar concentration of the NaOH aqueous solution is 1.0-1.6 mol / L, and the mass-to-volume ratio of ferrous chloride tetrahydrate to the NaOH aqueous solution in step S2 is 0.025-0.04 g / mL;

[0040] Preferably, in step S3, the reflux reaction temperature is 60-80℃, and the reflux reaction time is 3-5h;

[0041] S4. Accurately weigh copper nitrate trihydrate and zinc nitrate hexahydrate and dissolve them in deionized water to obtain a mixed salt solution. Disperse the Fe3O4 modified adsorbent material prepared in step S3 in deionized water to obtain a suspension. Slowly add the mixed salt solution to the suspension and raise the reaction temperature to carry out the coordination reaction. After the reaction is completed, separate the product with a magnet and wash it repeatedly with deionized water until no metal ions are detected in the filtrate. After drying, the water treatment adsorbent material is obtained.

[0042] Preferably, in step S4, the reaction temperature of the coordination reaction is 50-60℃, the stirring speed of the coordination reaction is 300-400 rpm, and the reaction time of the coordination reaction is 12-16 h.

[0043] The beneficial effects achieved by this invention are as follows:

[0044] This invention provides an adsorbent material for treating organic pollutants in water and its preparation method. Through a synergistic design involving monomer synthesis, multifunctional COF framework construction, magnetic modification, and bimetallic active site loading, this invention overcomes the bottlenecks of traditional adsorbent materials, such as low capacity, slow adsorption rate, difficult recovery, and poor selectivity. The COF framework structure has a high specific surface area, providing ample physical space. The high density of active sites enables efficient pollutant capture, resulting in an adsorption capacity far superior to traditional single-active-site adsorbent materials. The multi-mechanism synergy allows for efficient adsorption of various organic pollutants, including benzene compounds, polycyclic aromatic hydrocarbons, azo dyes, antibiotics, and pesticides, making it suitable for complex water quality scenarios. The COF framework is covalently linked, exhibiting excellent chemical stability. Metal ions are firmly loaded through coordination bonds, preventing metal ion loss during adsorption-desorption cycles. Adsorption performance remains stable even after multiple cycles. The directional coordination design avoids competition for active sites. The different coordination preferences of various metal ions for different pollutants, combined with the size sieving effect of the COF channels, preferentially adsorbs target organic pollutants, reducing impurity interference.

[0045] The amino group (-NH2) of monomer I (tetraaminoporphyrin) undergoes a Schiff base condensation reaction with the aldehyde group (-CHO) of monomer II (polyaldehyde aromatic monomer) to form an imine bond (-N=C-). This imine bond, along with the encapsulated imine bond, forms a crystalline COF framework. The imine bond enhances the framework's rigidity and chemical stability. The well-organized porous structure (micropores / mesopores) provides an ultra-large specific surface area and physical retention space, significantly increasing the probability of pollutant contact and directly improving the adsorption capacity. The conjugated framework (porphyrin ring, aromatic ring) provides a source of aromatic pollutants. Stacked interaction sites, adapted to nonpolar / weakly polar contaminants; first, Fe is reacted with ferric chloride and ferrous chloride solutions. 2+ Fe 3+ Fe3O4 nanoparticles are formed in situ by co-precipitation of the carboxyl groups of the COF framework, followed by alkaline-induced co-precipitation. The Fe3O4 nanoparticles are firmly bonded to the COF framework via carboxyl-Fe coordination bonds, without disrupting the porous structure of the COF. The magnetic properties of Fe3O4 allow for rapid separation of the adsorbent material via an external permanent magnet, solving the problems of difficult separation and high recovery costs associated with traditional adsorbent materials, thus enhancing its practical value. The Fe on the surface of Fe3O4... 2+ Fe 3+ The addition of new coordination sites, synergistic with the COF framework sites, enhances the adsorption strength for pollutants containing N / O heteroatoms. The spinel structure of Fe3O4 provides a basis for subsequent Cu...2+ / Zn 2+ Coordination provides rigid support, preventing the loss of active sites; a mixed salt solution of copper nitrate and zinc nitrate is mixed with Fe3O4-modified COF material, Cu 2+ / Zn 2+ Loaded onto the material surface through coordination, it mainly binds to the N atoms of the porphyrin group and the N atoms of the imine bond, while also binding to the Fe atoms on the Fe3O4 surface. 2+ Fe 3+ The formation of bridging coordination, a strong chemical interaction, ensures a firm bond between pollutants and the material, resulting in high adsorption stability, resistance to desorption, and an acid- and alkali-resistant COF framework with strong coordination bonds that prevents metal ion loss. This leads to the formation of a Fe-Cu-Zn multi-metal synergistic coordination network, where the metal ion valence state is stable (Fe...). 2+ / Fe 3+ Cu 2+ Zn 2+ Furthermore, it is uniformly dispersed on the inner wall of the COF pores and the surface of Fe3O4, without agglomeration. The coordination effect is a strong chemical effect, which makes the pollutants firmly bound to the material, resulting in high adsorption stability and difficulty in desorption. In addition, the acid and alkali resistant COF framework and strong coordination bonds prevent the loss of metal ions and avoid site competition, ensuring efficient utilization of each active site and improving adsorption selectivity. Attached Figure Description

[0046] Figure 1 This is a synthetic route diagram of material monomer II in Example 1 of the present invention;

[0047] Figure 2 The graph shows the adsorption capacity of the water treatment adsorbent materials described in Examples 1-3 and Comparative Examples 1-3 of this invention for methylene blue.

[0048] Figure 3 The graph shows the adsorption capacity results of the water treatment adsorption materials described in Examples 1-3 and Comparative Examples 1-3 of the present invention for Congo red.

[0049] Figure 4 The graph shows the adsorption capacity of the water treatment adsorption materials described in Examples 1-3 and Comparative Examples 1-3 of this invention for naphthalene.

[0050] Figure 5 The graph shows the adsorption capacity of the water treatment adsorption materials described in Examples 1-3 and Comparative Examples 1-3 of this invention for tetracycline.

[0051] The accompanying drawings are provided to further illustrate the invention and form part of the specification. They are used together with the embodiments of the invention to explain the invention and do not constitute a limitation thereof. Detailed Implementation

[0052] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection of the present invention.

[0053] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those familiar to those skilled in the art. Furthermore, any methods and materials similar to or equivalent to those described herein may be applied to this invention. The preferred embodiments and materials described herein are for illustrative purposes only and do not limit the scope of this application.

[0054] Unless otherwise specified, the experimental methods used in the following examples are conventional methods; unless otherwise specified, the experimental materials and test strains used in the following examples were purchased from commercial channels.

[0055] Example 1

[0056] This embodiment provides an organic pollutant water treatment adsorption material, which comprises the following components in parts by weight: 2.0 parts of material monomer I, 3.5 parts of material monomer II, 1.2 parts of ferrous chloride tetrahydrate, 3.2 parts of ferric chloride hexahydrate, 0.36 parts of copper nitrate trihydrate, and 0.45 parts of zinc nitrate hexahydrate;

[0057] The preparation method of material monomer I specifically includes the following steps:

[0058] A1. Accurately weigh 2.0 g of p-acetaminobenzaldehyde and 3.4 mL of freshly distilled pyrrole into a single-necked flask. After purging the air with flowing nitrogen, add 80 mL of anhydrous propionic acid and stir at 500 rpm until the reaction substrate is completely dissolved. Under light-protected conditions, raise the reaction temperature to 140 °C and reflux for 10 h. After the reaction is complete, allow the reaction system to cool naturally to room temperature, then transfer the reaction system to an ice-water bath and stir at 500 rpm to form a large amount of precipitate. Filter the precipitate, collect it, wash it three times with n-hexane, wash it with deionized water, purify it with dichloromethane and anhydrous methanol, and dry it under vacuum at 60 °C for 8 h to obtain intermediate product 1.

[0059] A2. Add 2.0 g of the intermediate product prepared in step A1 to the flask, and add an aqueous methanol solution (V). 甲醇 :V 水=2:1), after completely dissolving intermediate product 1 by sonication at 100W power for 10 min, add 0.48g of NaOH to the reaction system and stir at 400rpm. Maintain the reaction temperature at 35℃ and carry out alkaline hydrolysis reaction for 2.5h. After the reaction is completed, after the reaction system is cooled to room temperature, add 1mol / L hydrochloric acid aqueous solution to adjust the reaction pH to 3.0. Stir until no more precipitate is formed, filter, collect the precipitate, wash with deionized water and anhydrous methanol in sequence, and then purify by recrystallization with dichloromethane and n-hexane. Dry under vacuum at 50℃ for 6h to obtain material monomer I;

[0060] Figure 1 The figure shows the synthesis route of material monomer II in Example 1 of the present invention. The preparation method of material monomer II specifically includes the following steps:

[0061] B1. Accurately weigh 0.2 g of benzo[1,3]-dioxane-2-carboxylic acid and place it in a flask. Add 50 mL of 45 vol% HBr / acetic acid solution and stir at 300 rpm until the substrate is completely dissolved. Then, introduce flowing nitrogen gas and raise the reaction temperature to 130 °C. While maintaining the stirring speed at 300 rpm, add 2.7 mL of 1 mol / L liquid bromine / acetic acid solution to the reaction system dropwise through a constant pressure dropping funnel at a rate of 1 drop / s to carry out the bromination reaction. After the addition is complete, continue the reaction for 8 h. After the reaction is completed, let the reaction system cool to room temperature, add 10 wt% sodium sulfite aqueous solution and ice water to the reaction system, stir vigorously at 800 rpm for 10 min, filter, collect the solid, wash repeatedly with deionized water and anhydrous methanol, purify, and dry under vacuum at 60 °C for 8 h to obtain intermediate product 2.

[0062] B2. Maintaining a nitrogen atmosphere, place 0.36 g of the intermediate product 2 prepared in step B1 into a flask, add 0.08 g of benzene-1,3,5-trimethyltriboronic acid, and add THF / water solution (V). THF :V 水 After completely dissolving the reaction substrate (4:1), 4 mg of tetra(triphenylphosphine)palladium catalyst and 0.16 g of anhydrous potassium carbonate were added to the reaction system. The reaction system was mixed evenly at 300 rpm, and the reaction temperature was raised to 60 °C for reflux reaction for 8 h. After the reaction was completed, the reaction system was cooled to room temperature, ethyl acetate was added for extraction, the organic phase was collected, washed with saturated NaCl aqueous solution, dried with anhydrous sodium sulfate, concentrated under reduced pressure, purified, and dried under vacuum at 60 °C for 8 h to obtain intermediate product 3.

[0063] B3. Under a nitrogen atmosphere, place 0.16 g of the intermediate product 3 prepared in step B2 and 0.1 g of 4-formylphenylboronic acid in a flask, and add THF / water solution (V).THF :V 水 After the reaction substrate was completely dissolved (4:1), 5 mg of tetra(triphenylphosphine)palladium catalyst and 0.28 g of potassium carbonate were added and mixed evenly. The reaction temperature was raised to 80 °C and refluxed for 20 h. After the reaction was completed, the reaction system was allowed to cool naturally to room temperature. Ethyl acetate was added for extraction, the organic phase was collected, washed with saturated NaCl aqueous solution, dried with anhydrous sodium sulfate, concentrated under reduced pressure, purified, and dried under vacuum at 60 °C for 8 h to obtain material monomer II.

[0064] This embodiment also provides a method for preparing an adsorbent material for treating organic pollutants in water, specifically including the following steps:

[0065] S1. Take 2.0 g of monomer I and 3.5 g of monomer II and place them in a flask. Add 100 mL of 1,4-dioxane / DMF (volume ratio 1:1) mixed solvent and mix well. Then, introduce flowing nitrogen gas and add 10 mL of 6 mol / L acetic acid / ethanol solution dropwise using a constant pressure dropping funnel under nitrogen atmosphere. After the addition is complete, transfer the solution to a polytetrafluoroethylene reactor. Under sealed and light-protected conditions, raise the reaction temperature to 120 °C and reflux for 36 h. After the reaction is completed, let the reaction system cool naturally to room temperature and centrifuge at 8000 rpm for 10 min. Collect the precipitate and wash it with anhydrous DMF and anhydrous ethanol in sequence. After vacuum drying at 60 °C for 6 h, the adsorbent material precursor is obtained.

[0066] S2. Disperse the adsorbent precursor prepared in step S1 in 100 mL of ethanol-water solution (volume ratio 1:1), stir continuously at 300 rpm until homogeneous, and introduce high-purity flowing nitrogen gas. Under nitrogen atmosphere, dissolve 1.2 g of ferrous chloride tetrahydrate and 3.2 g of ferric chloride hexahydrate in 20 mL of anhydrous ethanol to obtain an iron salt / ethanol solution. Add the iron salt / ethanol solution dropwise to the reaction system at a stirring speed of 1 mL / min. After the addition is complete, maintain room temperature for coordination reaction for 24 h. After the reaction is completed, obtain the coordination solution.

[0067] S3. Place the complexation solution prepared in step S2 in a flask. Under a nitrogen atmosphere, take 48 mL of 1.0 mol / L NaOH aqueous solution and add it to the reaction system at a constant pressure dropping funnel at a rate of 1 mL / min. During the dropwise addition, stir and mix at a speed of 300 rpm to maintain the pH of the reaction system at 10.5. After the dropwise addition is complete, raise the reaction temperature to 70℃ and reflux the reaction at a stirring speed of 350 rpm for 3 h. After the reaction is complete, let the reaction system cool naturally to room temperature, centrifuge at 8000 rpm for 10 min, collect the precipitate, wash it repeatedly with deionized water until neutral, wash it again with anhydrous ethanol, and dry it under vacuum at 50℃ for 10 h to obtain the Fe3O4 modified adsorbent material.

[0068] S4. Accurately weigh 0.36 g of copper nitrate trihydrate and 0.45 g of zinc nitrate hexahydrate and dissolve them in 20 mL of deionized water to obtain a mixed salt solution. Disperse the Fe3O4 modified adsorbent material prepared in step S3 in 50 mL of deionized water to obtain a suspension. Slowly add the mixed salt solution to the suspension at a rate of 1 mL / min. Raise the reaction temperature to 50 °C and stir at a rate of 400 rpm to carry out the coordination reaction. After the reaction is completed, separate the product with a magnet and wash it repeatedly with deionized water until no metal ions are detected in the filtrate. After drying, obtain the water treatment adsorbent material.

[0069] Example 2

[0070] This embodiment provides an organic pollutant water treatment adsorption material, which comprises the following components in parts by weight: 3.0 parts of material monomer I, 5.5 parts of material monomer II, 1.8 parts of ferrous chloride tetrahydrate, 5.0 parts of ferric chloride hexahydrate, 1.0 part of copper nitrate trihydrate, and 0.3 parts of zinc nitrate hexahydrate;

[0071] The preparation method of material monomer I specifically includes the following steps:

[0072] A1. Accurately weigh 2.0 g of p-acetaminobenzaldehyde and 3.8 mL of freshly distilled pyrrole into a single-necked flask. After purging the air with flowing nitrogen, add 90 mL of anhydrous propionic acid and stir at 500 rpm until the reaction substrate is completely dissolved. Under light-protected conditions, raise the reaction temperature to 145 °C and reflux for 9 h. After the reaction is complete, allow the reaction system to cool naturally to room temperature, then transfer the reaction system to an ice-water bath and stir at 500 rpm to form a large amount of precipitate. Filter the precipitate, collect it, wash it three times with n-hexane, wash it with deionized water, purify it with dichloromethane and anhydrous methanol, and dry it under vacuum at 60 °C for 8 h to obtain intermediate product 1.

[0073] A2. Add 2.2 g of the intermediate product prepared in step A1 to the flask, and add an aqueous methanol solution (V). 甲醇 :V 水 =2:1), after completely dissolving intermediate product 1 by sonication at 100W power for 10 min, add 0.42g of NaOH to the reaction system, stir at 500rpm, maintain the reaction temperature at 40℃, and carry out alkaline hydrolysis reaction for 1.5h. After the reaction is completed, after the reaction system is cooled to room temperature, add 1mol / L hydrochloric acid aqueous solution to adjust the reaction pH to 3.5, stir until no more precipitate is formed, filter, collect the precipitate, wash with deionized water and anhydrous methanol in sequence, recrystallize and purify with dichloromethane and n-hexane, and dry under vacuum at 50℃ for 6h to obtain material monomer I;

[0074] The preparation method of material monomer II specifically includes the following steps:

[0075] B1. Accurately weigh 0.2 g of benzo[1,3]-dioxane-2-carboxylic acid and place it in a flask. Add 50 mL of 45 vol% HBr / acetic acid solution and stir at 300 rpm until the substrate is completely dissolved. Then, introduce flowing nitrogen gas and raise the reaction temperature to 120 °C. While maintaining the stirring speed at 300 rpm, add 3.0 mL of 1 mol / L liquid bromine / acetic acid solution to the reaction system dropwise through a constant pressure dropping funnel at a rate of 1 drop / s to carry out the bromination reaction. After the addition is complete, continue the reaction for 12 h. After the reaction is completed, let the reaction system cool to room temperature, add 10 wt% sodium sulfite aqueous solution and ice water to the reaction system, stir vigorously at 800 rpm for 10 min, filter, collect the solid, wash repeatedly with deionized water and anhydrous methanol, purify, and dry under vacuum at 60 °C for 8 h to obtain intermediate product 2.

[0076] B2. Maintaining a nitrogen atmosphere, place 0.36 g of the intermediate product 2 prepared in step B1 into a flask, add 0.07 g of benzene-1,3,5-trimethyltriboronic acid, and add THF / water solution (V). THF :V 水 After completely dissolving the reaction substrate (4:1), 5 mg of tetra(triphenylphosphine)palladium catalyst and 0.16 g of anhydrous potassium carbonate were added to the reaction system. The reaction system was mixed evenly at 300 rpm, and the reaction temperature was raised to 65 °C for reflux reaction. The reaction was carried out for 7 h. After the reaction was completed, the reaction system was cooled to room temperature, ethyl acetate was added for extraction, the organic phase was collected, washed with saturated NaCl aqueous solution, dried with anhydrous sodium sulfate, concentrated under reduced pressure, purified, and dried under vacuum at 60 °C for 8 h to obtain intermediate product 3.

[0077] B3. Under a nitrogen atmosphere, place 0.15 g of the intermediate product 3 prepared in step B2 and 0.1 g of 4-formylphenylboronic acid in a flask, and add THF / water solution (V). THF :V 水 After the reaction substrate was completely dissolved (4:1), 7.5 mg of tetra(triphenylphosphine)palladium catalyst and 0.25 g of potassium carbonate were added and mixed evenly. The reaction temperature was raised to 85 °C and refluxed for 18 h. After the reaction was completed, the reaction system was allowed to cool naturally to room temperature. Ethyl acetate was added for extraction, the organic phase was collected, washed with saturated NaCl aqueous solution, dried with anhydrous sodium sulfate, concentrated under reduced pressure, purified, and dried under vacuum at 60 °C for 8 h to obtain material monomer II.

[0078] This embodiment also provides a method for preparing an adsorbent material for treating organic pollutants in water, specifically including the following steps:

[0079] S1. Take 3.0 g of monomer I and 5.5 g of monomer II and place them in a flask. Add 100 mL of 1,4-dioxane / DMF (volume ratio 1:1) mixed solvent and mix well. Then, introduce flowing nitrogen gas and add 15 mL of 6 mol / L acetic acid / ethanol solution dropwise using a constant pressure dropping funnel under nitrogen atmosphere. After the addition is complete, transfer the solution to a polytetrafluoroethylene reactor. Under sealed and light-protected conditions, raise the reaction temperature to 135 °C and reflux for 30 h. After the reaction is completed, let the reaction system cool naturally to room temperature and centrifuge at 8000 rpm for 10 min. Collect the precipitate and wash it with anhydrous DMF and anhydrous ethanol in sequence. After vacuum drying at 60 °C for 6 h, the adsorbent material precursor is obtained.

[0080] S2. Disperse the adsorbent precursor prepared in step S1 in 100 mL of ethanol-water solution (volume ratio 1:1), stir continuously at 350 rpm until homogeneous, and introduce high-purity flowing nitrogen gas. Under nitrogen atmosphere, dissolve 1.8 g of ferrous chloride tetrahydrate and 5.0 g of ferric chloride hexahydrate in 20 mL of anhydrous ethanol to obtain an iron salt / ethanol solution. Add the iron salt / ethanol solution dropwise to the reaction system at a stirring speed of 1 mL / min. After the addition is complete, maintain room temperature for coordination reaction for 21 h. After the reaction is completed, obtain the coordination solution.

[0081] S3. Place the complexation solution prepared in step S2 in a flask. Under a nitrogen atmosphere, add 50 mL of 1.6 mol / L NaOH aqueous solution to the reaction system at a constant pressure dropping funnel at a rate of 1 mL / min. During the dropwise addition, stir at a speed of 300 rpm to maintain the pH of the reaction system at 11.0. After the dropwise addition is complete, raise the reaction temperature to 60℃ and reflux the reaction at a stirring speed of 350 rpm for 5 h. After the reaction is complete, let the reaction system cool naturally to room temperature, centrifuge at 8000 rpm for 10 min, collect the precipitate, wash repeatedly with deionized water until neutral, wash again with anhydrous ethanol, and vacuum dry at 50℃ for 10 h to obtain Fe3O4 modified adsorbent material.

[0082] S4. Accurately weigh 1.0 g of copper nitrate trihydrate and 0.30 g of zinc nitrate hexahydrate and dissolve them in 20 mL of deionized water to obtain a mixed salt solution. Disperse the Fe3O4 modified adsorbent material prepared in step S3 in 50 mL of deionized water to obtain a suspension. Slowly add the mixed salt solution to the suspension at a rate of 1 mL / min. Raise the reaction temperature to 55℃ and stir at a rate of 400 rpm to carry out the coordination reaction. After the reaction is completed, separate the product with a magnet and wash it repeatedly with deionized water until no metal ions are detected in the filtrate. After drying, the water treatment adsorbent material is obtained.

[0083] Example 3

[0084] This embodiment provides an organic pollutant water treatment adsorption material, which comprises the following components in parts by weight: 4.0 parts of material monomer I, 7.0 parts of material monomer II, 2.4 parts of ferrous chloride tetrahydrate, 6.5 parts of ferric chloride hexahydrate, 0.5 parts of copper nitrate trihydrate, and 1.2 parts of zinc nitrate hexahydrate;

[0085] The preparation method of material monomer I specifically includes the following steps:

[0086] A1. Accurately weigh 2.0 g of p-acetaminobenzaldehyde and 4.2 mL of freshly distilled pyrrole into a single-necked flask. After purging the air with flowing nitrogen, add 100 mL of anhydrous propionic acid and stir at 500 rpm until the reaction substrate is completely dissolved. Under light-protected conditions, raise the reaction temperature to 150 °C and reflux for 8 h. After the reaction is complete, allow the reaction system to cool naturally to room temperature, then transfer the reaction system to an ice-water bath and stir at 500 rpm to form a large amount of precipitate. Filter the precipitate, collect it, wash it three times with n-hexane, wash it with deionized water, purify it with dichloromethane and anhydrous methanol, and dry it under vacuum at 60 °C for 8 h to obtain intermediate product 1.

[0087] A2. Add 2.4 g of the intermediate product prepared in step A1 to the flask, and add an aqueous methanol solution (V). 甲醇 :V 水 =2:1), after completely dissolving intermediate product 1 by sonication at 100W power for 10 min, add 0.50g of NaOH to the reaction system, stir at 450rpm, maintain the reaction temperature at 38℃, and carry out alkaline hydrolysis reaction for 2h. After the reaction is completed, after the reaction system is cooled to room temperature, add 1mol / L hydrochloric acid aqueous solution to adjust the reaction pH to 4.0, stir until no more precipitate is formed, filter, collect the precipitate, wash with deionized water and anhydrous methanol in sequence, recrystallize and purify with dichloromethane and n-hexane, and dry under vacuum at 50℃ for 6h to obtain material monomer I;

[0088] The preparation method of material monomer II specifically includes the following steps:

[0089] B1. Accurately weigh 0.2 g of benzo[1,3]-dioxane-2-carboxylic acid and place it in a flask. Add 50 mL of 45 vol% HBr / acetic acid solution and stir at 300 rpm until the substrate is completely dissolved. Then, introduce flowing nitrogen gas and raise the reaction temperature to 125 °C. While maintaining the stirring speed at 300 rpm, add 3.5 mL of 1 mol / L liquid bromine / acetic acid solution to the reaction system dropwise through a constant pressure dropping funnel at a rate of 1 drop / s to carry out the bromination reaction. After the addition is complete, continue the reaction for 10 h. After the reaction is completed, let the reaction system cool to room temperature, add 10 wt% sodium sulfite aqueous solution and ice water to the reaction system, stir vigorously at 800 rpm for 10 min, filter, collect the solid, wash repeatedly with deionized water and anhydrous methanol, purify, and dry under vacuum at 60 °C for 8 h to obtain intermediate product 2.

[0090] B2. Maintaining a nitrogen atmosphere, place 0.36 g of the intermediate product 2 prepared in step B1 into a flask, add 0.06 g of benzene-1,3,5-trimethyltriboronic acid, and add THF / water solution (V). THF :V 水 After completely dissolving the reaction substrate (4:1), 6 mg of tetra(triphenylphosphine)palladium catalyst and 0.11 g of anhydrous potassium carbonate were added to the reaction system. The reaction system was mixed evenly at 300 rpm, and the reaction temperature was raised to 70 °C for reflux reaction for 6 h. After the reaction was completed, the reaction system was cooled to room temperature, ethyl acetate was added for extraction, the organic phase was collected, washed with saturated NaCl aqueous solution, dried with anhydrous sodium sulfate, concentrated under reduced pressure, purified, and dried under vacuum at 60 °C for 8 h to obtain intermediate product 3.

[0091] B3. Under a nitrogen atmosphere, place 0.14 g of the intermediate product 3 prepared in step B2 and 0.1 g of 4-formylphenylboronic acid in a flask, and add THF / water solution (V). THF :V 水 After the reaction substrate was completely dissolved (4:1), 10 mg of tetra(triphenylphosphine)palladium catalyst and 0.23 g of potassium carbonate were added and mixed evenly. The reaction temperature was raised to 90 °C and refluxed for 15 h. After the reaction was completed, the reaction system was allowed to cool naturally to room temperature. Ethyl acetate was added for extraction, the organic phase was collected, washed with saturated NaCl aqueous solution, dried with anhydrous sodium sulfate, concentrated under reduced pressure, purified, and dried under vacuum at 60 °C for 8 h to obtain material monomer II.

[0092] This embodiment also provides a method for preparing an adsorbent material for treating organic pollutants in water, specifically including the following steps:

[0093] S1. Take 4.0 g of monomer I and 7.0 g of monomer II and place them in a flask. Add 100 mL of 1,4-dioxane / DMF (volume ratio 1:1) mixed solvent and mix well. Then, introduce flowing nitrogen gas and add 20 mL of 6 mol / L acetic acid / ethanol solution dropwise using a constant pressure dropping funnel under nitrogen atmosphere. After the addition is complete, transfer the solution to a polytetrafluoroethylene reactor. Under sealed and light-protected conditions, raise the reaction temperature to 150 °C and reflux for 24 h. After the reaction is completed, let the reaction system cool naturally to room temperature and centrifuge at 8000 rpm for 10 min. Collect the precipitate and wash it with anhydrous DMF and anhydrous ethanol in sequence. After vacuum drying at 60 °C for 6 h, the adsorbent material precursor is obtained.

[0094] S2. Disperse the adsorbent precursor prepared in step S1 in 100 mL of ethanol-water solution (volume ratio 1:1), stir continuously at 400 rpm until homogeneous, and introduce high-purity flowing nitrogen gas. Under nitrogen atmosphere, dissolve 2.4 g of ferrous chloride tetrahydrate and 6.5 g of ferric chloride hexahydrate in 20 mL of anhydrous ethanol to obtain an iron salt / ethanol solution. Add the iron salt / ethanol solution dropwise to the reaction system at a stirring speed of 1 mL / min. After the addition is complete, maintain room temperature for coordination reaction for 18 h. After the reaction is completed, obtain the coordination solution.

[0095] S3. Place the complexation solution prepared in step S2 in a flask. Under a nitrogen atmosphere, add 40 mL of 1.4 mol / L NaOH aqueous solution to the reaction system at a constant pressure dropping funnel at a rate of 1 mL / min. During the dropwise addition, stir at 300 rpm to maintain the pH of the reaction system at 10.8. After the dropwise addition is complete, raise the reaction temperature to 80℃ and reflux the reaction at 350 rpm for 3 h. After the reaction is complete, let the reaction system cool naturally to room temperature, centrifuge at 8000 rpm for 10 min, collect the precipitate, wash repeatedly with deionized water until neutral, wash again with anhydrous ethanol, and vacuum dry at 50℃ for 10 h to obtain the Fe3O4 modified adsorbent material.

[0096] S4. Accurately weigh 0.5g of copper nitrate trihydrate and 1.2g of zinc nitrate hexahydrate and dissolve them in 20mL of deionized water to obtain a mixed salt solution. Disperse the Fe3O4 modified adsorbent material prepared in step S3 in 50mL of deionized water to obtain a suspension. Slowly add the mixed salt solution to the suspension at a rate of 1mL / min. Raise the reaction temperature to 60℃ and stir at a rate of 400rpm to carry out the coordination reaction. After the reaction is completed, separate the product with a magnet and wash it repeatedly with deionized water until no metal ions are detected in the filtrate. After drying, the water treatment adsorbent material is obtained.

[0097] Comparative Example 1

[0098] This comparative example provides a water treatment adsorption material and its preparation method. The only difference between this example and Example 1 is that the same weight parts of triphenylformaldehyde are used to replace material monomer II, while the other components and their contents are the same as in Example 1.

[0099] Comparative Example 2

[0100] This comparative example provides a water treatment adsorbent material and its preparation method. The only difference between this example and Example 1 is that the water treatment adsorbent material does not include ferrous chloride tetrahydrate and ferric chloride hexahydrate, and the preparation method of this water treatment adsorbent material does not include steps S2 and S3. The remaining components and their contents are the same as in Example 1.

[0101] Comparative Example 3

[0102] This comparative example provides a water treatment adsorbent material and its preparation method. The only difference between this example and Example 1 is that the water treatment adsorbent material does not include copper nitrate trihydrate and zinc nitrate hexahydrate, and the preparation method of this water treatment adsorbent material does not include step S4. The remaining components and their contents are the same as in Example 1.

[0103] Experimental Example

[0104] This experiment investigates the adsorption of organic pollutants on the water treatment adsorbents prepared in Examples 1-3 and Comparative Examples 1-3. Typical organic pollutants, such as methylene blue, Congo red, naphthalene, and tetracycline, representing different types of organic pollutants, were selected. A 1000 mg / L stock solution of organic pollutants was prepared. The water treatment adsorbents from Examples 1-3 and Comparative Examples 1-3 were prepared, ground, and passed through a 200-mesh sieve. 0.02 g of the water treatment adsorbents prepared in Examples 1-3 and Comparative Examples 1-3 were accurately weighed and added to 50 mL of an organic pollutant solution with an initial concentration of 100 mg / L (pH=7.0, room temperature 25℃). The mixture was placed in a 300 rpm constant-temperature shaker, and samples were taken at 0, 5, 10, 20, 30, 60, 120, 240, 360, and 720 min. Each time, 2 mL of the suspension was taken, centrifuged at 8000 rpm for 5 min, and the supernatant was collected. The concentration of pollutants in the supernatant was determined, and the adsorption capacity q was calculated using the following formula. t (mg / g):

[0105] ;

[0106] Where C0 is the initial concentration (mg / L), C t Where t is the concentration (mg / L), V is the solution volume (L), and m is the material mass (g);

[0107] Figure 2 The graph shows the adsorption capacity results of the water treatment adsorbent materials described in Examples 1-3 and Comparative Examples 1-3 for methylene blue. Figure 3 The graph shows the adsorption capacity results of the water treatment adsorbent materials described in Examples 1-3 and Comparative Examples 1-3 for Congo red. Figure 4 The graph shows the adsorption capacity results of the water treatment adsorption materials for naphthalene described in Examples 1-3 and Comparative Examples 1-3 of this invention. Figure 5 The following table shows the adsorption capacity results of the water treatment adsorbent materials described in Examples 1-3 and Comparative Examples 1-3 for tetracycline. The adsorption kinetics were fitted using pseudo-first-order and pseudo-second-order kinetic models. The table below summarizes the fitting results of the pollutant adsorption kinetics:

[0108] ;

[0109] As shown in the figure, the embodiment exhibits the highest adsorption capacity for TC and MB because these two pollutants can form a multi-mechanism synergistic effect with the material, while naphthalene only depends on... The single stacking mechanism has the lowest capacity, but the examples can still improve the naphthalene adsorption capacity through COF framework optimization. The capacity of Example 3 is higher than that of Examples 1-2. As the amount of monomer and metal salt increases, the density of active sites increases synchronously, proving the effectiveness of component ratio control. The adsorption rate and kinetic model are the dominant mechanisms, directly reflecting the binding efficiency and diffusion resistance between pollutants and the active sites of water treatment adsorption materials. The k2 of the examples is higher than that of the comparative examples. The pores of the examples are regular and unobstructed, with low pollutant diffusion resistance and a high probability of collision with sites. The magnetic mass transfer assisted by Fe3O4 avoids the aggregation of water treatment adsorption materials during adsorption, improves dispersion, accelerates pollutant diffusion, and indirectly improves the adsorption rate. The high density of multi-metal sites results in a fast chemical binding rate. Because methylene blue and tetracycline are chemically bound through coordination and electrostatic interactions, the adsorption rate is faster than that of Congo red through electrostatic / hydrogen bonding. The hydrophobicity of naphthalene leads to a slow diffusion rate. Stacking interactions are weaker than chemical coordination.

[0110] All examples are pseudo-second-order dominant, corresponding to chemisorption in the pseudo-second-order model. This demonstrates that the adsorption process in these examples is controlled by the chemical binding of pollutants to active sites, rather than simple pore diffusion, through coordination, electrostatic adsorption, and strong hydrogen bonding. This aligns with the logic of multi-metal synergistic adsorption, and the pseudo-second-order theoretical equilibrium adsorption capacity (q) is within acceptable limits. e,cal The model shows a small error compared to the actual value, indicating a very high model fit and demonstrating the stability of the chemisorption mechanism. Comparative Example 1 shows that the model is predominantly quasi-first-order dominant (R0). 2 1≥0.895): After replacing monomer II with triphenylformaldehyde, no carboxyl-directed anchoring of Fe 3+ This leads to Fe3O4 agglomeration and blockage of pores, making pollutant diffusion resistance the controlling step in adsorption rate. Therefore, the pseudo-first-order model (diffusion control) has a higher fit, and k1 (0.7-1.5×10) -3 min -1 The adsorption rate was significantly lower than in the examples, and the adsorption rate was extremely slow. Comparative Examples 2-3 were still predominantly secondary (R0). 2 2≥0.968): Although Fe or Cu / Zn is missing, single chemical interactions, such as coordination, still exist, so chemisorption remains dominant. However, insufficient site density leads to a lower k2 than in the example. The four pollutants represent different types (cationic / anionic / nonpolar / containing heteroatoms), and their differences in adsorption performance reflect the broad-spectrum adaptability of the material. The absence of carboxyl groups leads to Fe3O4 agglomeration and pore blockage, and the absence of heterocycles leads to a decrease in the hydrophobicity / conjugation of the COF framework. Ultimately, the adsorption capacity and rate are the lowest, proving that the structure of monomer II is the basis for ensuring pore unobstructedness and active site density. Fe 2+ / Fe 3+This results in a reduction in coordination sites and a lack of magnetically assisted mass transfer, leading to lower adsorption rates and capacities compared to the examples. Furthermore, centrifugation is required after adsorption (unlike the examples where rapid magnetic separation is possible), reducing practical value. The single Fe site also exhibits insufficient adaptability to pollutants containing N / O / S heteroatoms, resulting in lower adsorption capacities for methylene blue tetracycline and Congo red compared to the examples. This demonstrates that Cu... 2+ / Zn 2+ The introduction of [a specific ingredient] can broaden the adsorption range and enhance the adsorption intensity.

[0111] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention.

[0112] The present invention and its embodiments have been described above. This description is not restrictive, and the accompanying drawings are only one embodiment of the present invention. The actual application is not limited to this. In conclusion, if those skilled in the art are inspired by this description and design similar methods and embodiments without departing from the spirit of the present invention, they should all fall within the protection scope of the present invention.

Claims

1. A method for preparing an adsorbent material for treating organic pollutants in water, characterized in that: Specifically, the following steps are included: S1. Place material monomer I and material monomer II in a flask, add 1,4-dioxane / DMF mixed solvent, mix well, and then introduce flowing nitrogen gas. Under the nitrogen atmosphere, add acetic acid / ethanol solution dropwise using a constant pressure dropping funnel. After the addition is complete, transfer to a polytetrafluoroethylene reaction vessel. Under sealed and light-proof conditions, raise the reaction temperature to carry out the reflux reaction. After the reaction is completed, cool, centrifuge, collect the precipitate, wash with anhydrous DMF and anhydrous ethanol, and dry to obtain the adsorbent material precursor. S2. Disperse the adsorbent precursor prepared in step S1 in an ethanol-water solution, introduce high-purity flowing nitrogen gas, and add iron salt / ethanol solution dropwise to the reaction system under a nitrogen atmosphere. After the addition is complete, maintain room temperature to carry out the coordination reaction. After the reaction is completed, a coordination solution is obtained. The iron salt / ethanol solution is prepared by dissolving ferrous chloride tetrahydrate and ferric chloride hexahydrate in anhydrous ethanol under a nitrogen atmosphere. S3. Take the complexation solution prepared in step S2, and add NaOH aqueous solution dropwise to the reaction system under a nitrogen atmosphere using a constant pressure dropping funnel. Keep the pH of the reaction system at 10.5-11. After the addition is complete, raise the reaction temperature to carry out the reflux reaction. After the reaction is completed, cool, centrifuge, collect the precipitate, wash with deionized water, and dry to obtain Fe3O4 modified adsorbent material. S4. Accurately weigh copper nitrate trihydrate and zinc nitrate hexahydrate and dissolve them in deionized water to obtain a mixed salt solution. Disperse the Fe3O4 modified adsorbent material prepared in step S3 in deionized water to obtain a suspension. Slowly add the mixed salt solution to the suspension and raise the reaction temperature to carry out the coordination reaction. After the reaction is completed, separate the product with a magnet and wash it repeatedly with deionized water until no metal ions are detected in the filtrate. After drying, the water treatment adsorbent material is obtained. The monomer I of the material is tetraaminophenylporphyrin; the structural formula of the monomer II of the material is shown below: 。 2. The method for preparing an adsorbent material for treating organic pollutants in water according to claim 1, characterized in that: The preparation method of the material monomer I specifically includes the following steps: A1. Place p-acetaminobenzaldehyde and pyrrole in a flask, add anhydrous propionic acid, and after the reaction substrate is completely dissolved, pass flowing nitrogen gas through it. Under light-protected conditions, raise the reaction temperature to carry out the reflux reaction. After the reaction is completed, cool it and transfer the reaction system to an ice-water bath to form a precipitate. Filter the precipitate, collect it, wash it with n-hexane and deionized water in sequence, purify it, and dry it to obtain intermediate product 1. A2. Dissolve intermediate product 1 prepared in step A1 in methanol aqueous solution, add NaOH, maintain the reaction temperature to carry out alkaline hydrolysis reaction, after the reaction is completed, cool, add hydrochloric acid aqueous solution to adjust the pH of the reaction system to 3-4, after precipitate is formed, filter, collect the precipitate, purify and dry to obtain material monomer I.

3. The method for preparing an adsorbent material for organic pollutant water treatment according to claim 1, characterized in that: The preparation method of the material monomer II specifically includes the following steps: B1. Mix benzo[1,3]m-dioxacyclopentene-2-carboxylic acid with HBr / acetic acid solution. After mixing evenly, place the reaction system in an ice-water bath and raise the reaction temperature. Slowly add liquid bromine solution through a constant pressure dropping funnel to carry out the bromination reaction. After the addition is complete, continue the reaction. After the reaction is complete, add sodium sulfite aqueous solution and ice water to the reaction system. A precipitate will form. Filter, collect the filter cake, wash and dry to obtain intermediate product 2. B2. Under a nitrogen atmosphere, the intermediate product 2, benzene-1,3,5-trimethyltriboronic acid prepared in step B1, was placed in a flask. After the reaction substrate was completely dissolved by adding THF / water solution, tetrakis(triphenylphosphine)palladium catalyst and potassium carbonate were added. After mixing evenly, the reaction temperature was raised to reflux reaction. After the reaction was completed, the mixture was cooled, and ethyl acetate was added for extraction. The organic phase was collected and washed with saturated NaCl water solution. The organic phase was dried with anhydrous sodium sulfate, concentrated under reduced pressure, purified and dried to obtain intermediate product 3. B3. Under a nitrogen atmosphere, the intermediate product 3 prepared in step B2 and 4-formylphenylboronic acid were placed in a flask. After the reaction substrate was completely dissolved by adding THF / water solution, tetrakis(triphenylphosphine)palladium catalyst and potassium carbonate were added. After mixing evenly, the reaction temperature was raised to reflux reaction. After the reaction was completed, the mixture was cooled, and ethyl acetate was added for extraction. The organic phase was collected and washed with saturated NaCl water solution. After drying the organic phase with anhydrous sodium sulfate, it was concentrated under reduced pressure, purified and dried to obtain material monomer II.

4. The method for preparing an adsorbent material for organic pollutant water treatment according to claim 1, characterized in that: The water treatment adsorption material comprises the following components in parts by weight: 2-4 parts of material monomer I, 3.5-7 parts of material monomer II, 1.2-2.4 parts of ferrous chloride tetrahydrate, 3.2-6.5 parts of ferric chloride hexahydrate, 0.36-1.0 parts of copper nitrate trihydrate, and 0.3-1.2 parts of zinc nitrate hexahydrate.

5. The method for preparing an adsorbent material for organic pollutant water treatment according to claim 2, characterized in that: In step A1, the mass-to-volume ratio of p-acetaminobenzaldehyde to pyrrole is 1 g: 1.7-2.1 mL; in step A1, the mass concentration of p-acetaminobenzaldehyde in anhydrous propionic acid is 0.02-0.025 g / mL; in step A1, the reflux reaction temperature is 140-150 °C, and the reflux reaction time is 8-10 h. In step A2, the mass ratio of intermediate product 1 to NaOH is 1:0.19-0.24; in step A2, the reaction temperature of the alkaline hydrolysis reaction is 35-40℃, the reaction time of the alkaline hydrolysis reaction is 1.5-2.5h, and the stirring speed of the alkaline hydrolysis reaction is 400-500rpm.

6. The method for preparing an adsorbent material for organic pollutant water treatment according to claim 3, characterized in that: In step B1, the mass-to-volume ratio of the benzo[1,3]-dioxacyclopentene-2-carboxylic acid to the liquid bromine solution is 0.057-0.074 g / mL; in step B1, the reaction temperature of the bromination reaction is 120-130℃, and the reaction time of the bromination reaction is 8-12 h.

7. The method for preparing an adsorbent material for organic pollutant water treatment according to claim 3, characterized in that: In step B2, the mass ratio of benzene-1,3,5-trimethyltriboronic acid to intermediate product 2 is 1:0.45-0.60; in step B2, the amount of tetra(triphenylphosphine)palladium catalyst added is 5%-10% of the mass of benzene-1,3,5-trimethyltriboronic acid; in step B2, the mass ratio of potassium carbonate to benzene-1,3,5-trimethyltriboronic acid is 1.8-2.3:1; in step B2, the reflux reaction temperature is 60-70℃, and the reflux reaction time is 6-8h.

8. The method for preparing an adsorbent material for treating organic pollutants in water according to claim 3, characterized in that: In step B3, the mass ratio of 4-formylphenylboronic acid to intermediate product 3 is 1:1.4-1.6; in step B3, the amount of tetrakis(triphenylphosphine)palladium catalyst added is 5%-10% of the mass of 4-formylphenylboronic acid; in step B3, the mass ratio of potassium carbonate to 4-formylphenylboronic acid is 2.3-2.8:1; in step B3, the reflux reaction temperature is 80-90℃, and the reflux reaction time is 15-20h.

9. The method for preparing an adsorbent material for organic pollutant water treatment according to claim 1, characterized in that: In step S1, the volume ratio between the 1,4-dioxane / DMF mixed solvent and the acetic acid / ethanol solution is 10:1-2; in step S1, the reflux reaction temperature is 120-150℃, and the reflux reaction time is 24-36h. In step S2, the mass concentration of ferric chloride hexahydrate in anhydrous ethanol is 0.08-0.135 g / mL; in step S2, the reaction time of the coordination reaction is 18-24 h, and the stirring speed of the coordination reaction is 300-400 rpm.

10. The method for preparing an adsorbent material for treating organic pollutants in water according to claim 1, characterized in that: In step S3, the molar concentration of the NaOH aqueous solution is 1.0-1.6 mol / L; in step S3, the mass-to-volume ratio of ferrous chloride tetrahydrate to the NaOH aqueous solution in step S2 is 0.025-0.04 g / mL; in step S3, the reflux reaction temperature is 60-80℃, and the reflux reaction time is 3-5 h; in step S4, the coordination reaction temperature is 50-60℃, the coordination reaction stirring speed is 300-400 rpm, and the coordination reaction time is 12-16 h.

Images