Immobilized tetraamide hexamethyl phenyl ring ferromagnetic nanocomposite, synthesis method and application thereof

Abstract

The application discloses a kind of immobilized tetraamido macrocyclic ligand-Fe (III) magnetic composite material and its synthesis method and application, wherein immobilized tetraamido macrocyclic ligand-Fe (III) magnetic nanocomposite material includes cetyltrimethylammonium bromide and tetraamido macrocyclic ligand-Fe (III).The synthesis method of the application is short in time consumption and mild in reaction condition, simple in operation, reduces the preparation cost, by surfactant assisted self-assembly (SAS) method constructs Fe (III) -TAML based magnetic nanostructure, to improve the reactivity and recoverability of Fe (III) -TAML activator, to realize the degradation of bisphenol compounds under the condition of adding hydrogen peroxide at pH=10 and pH=7, conducive to realize popularization and application.

Description

Technical Field

[0001] This invention belongs to the field of persistent organic pollutant degradation, specifically relating to an immobilized tetraamide-hexamethylphenylcycloferromagnetic nanocomposite material, its synthesis method, and its application. Background Technology

[0002] Currently, Fe(III)-TAML is a catalyst with functions similar to peroxidase and cytochrome P450 enzymes (KUNDU S, THOMPSON JVK, et al., Activation parameters as mechanistic probes in the TAML Iron(V)-Oxo oxidations of hydrocarbons, Chemistry-a European Journal 21 (2015) 1803-1810). Under the excitation of peroxides, it forms a highly oxidizing high-valent iron complex, used for the degradation of dyes (WARNER GR, MILLS MR, et al., Reactivity and operational stability of N-tailed TAMLs through kinetic studies of the catalyzed oxidation of orange II by H2O2: synthesis and X-ray structure of an N-phenyl TAML, Chemistry-a European Journal 21 (2015) 6226-6233) and phenols (WANG C, GAO J, et al., Rapid destruction of tetrabromobisphenol a by Iron(III)-Tetraamidomacrocyclic ligand / layereddouble hydroxide composite / H2O2 system, Environmental Science&Technology 51(2017)488-496), estrogen (SHAPPELL NW, VRABEL MA, et al., Destruction of estrogensusing Fe-TAML / peroxide catalysis, Environmental Science & Technology 42(2008)1296-1300), organophosphorus pesticides (CHANDAA, KHETAN SK, etal.Total degradation of fenitrothion and other organophosphorus pesticides by catalytic oxidation employing Fe-TAML peroxide activators, Journal of the American Chemical Society 128(2006)12058-12059, and persistent aromatic organic pollutants (ACs) in various wastewaters, including drugs (SHEN LQ, BEACH ES, et al., Rapid, biomimetic degradation in water of the persistent drug sertraline by TAML catalysts and hydrogen peroxide, Environmental Science & Technology 45(2011)7882-7887). After treatment with Fe(III)-TAML / H2O2, the toxicity of the wastewater was significantly reduced, and its oxidation activity for ACs was higher than that of the free radical degradation technology generated by advanced oxidation (AOP). Furthermore, the residual Fe(III)-TAML showed no significant toxic effects on fish and microorganisms (ELLIS WC, TRAN CT, et al., Designing green oxidation catalysts for purifying environmental waters, Journal of the American Chemical Society 132(2010)9774-9781).

[0003] Fe(III)-TAML is a negatively charged metalloporphyrin-like molecule. Immobilizing metalloporphyrin molecules on a support can significantly improve their catalytic activity, structural stability, and reusability. Magnetite is a strongly magnetic oxide mineral with good electrical conductivity. The prepared magnetic composite material can be directly separated from the reaction solution by magnetic adsorption, achieving reuse and facilitating the promotion and application of Fe(III)-TAML, ultimately reducing overall environmental costs. Currently, among the self-assembly methods for synthesizing solid macromolecules based on porphyrin-like molecules, surfactant-assisted self-assembly (SAS) has advantages such as hierarchical assembly, ease of operation, and adjustability, and has attracted widespread attention from researchers in recent years. Driven by interparticle interactions, Wei et al. used surfactants to assist in the nucleation and growth of nanoparticles, preparing optically and electroactive nanomaterials with hierarchical structures and functions (Wei W, Bai F, et al., Surfactant-Assisted Cooperative Self-assembly of nanoparticles into active nanostructures, Iscience 11(2019)272-293).

[0004] Bisphenols (BPs) are typical endocrine disruptors (EDCs) with two phenolic groups. Due to their good ductility, high temperature resistance, and stable properties, they are widely used in industrial production and are often used as plastic additives. In addition, they also play an indispensable role in coatings, membrane materials, electronic product manufacturing, and product packaging (CHEN X, LID, et al., Study on synthesis and application of bisphenols, Guangzhou Chemical Industry 44 (2016) 26-28). Due to their long-term presence in the environment, these pollutants can leach out from the plastic itself under the influence of certain environmental factors and accumulate in soil, dust, sludge and water, posing a potential hazard to human health and the ecological environment. For example, bisphenol A (BPA), a plastic additive commonly used in food packaging, can be released from plastics (LIU X, SHI H, et al., Microplastics as both a sink and a source of bisphenol A in the marine environment, Environmental Science & Technology 53(2019)10188-10196). Summary of the Invention

[0005] Purpose of the invention: To address the shortcomings of existing technologies, this invention provides an immobilized tetraamide-hexamethylphenylcycloferromagnetic nanocomposite material that is simple to prepare and improves the utilization rate of Fe(III)-TAML. The magnetic nanocomposite material comprises hexadecyltrimethylammonium bromide and tetraamide-hexamethylphenylcycloferromagnetic nanocomposite material.

[0006] The present invention also provides a method for synthesizing and applying the immobilized tetraamide-based hexamethylphenylcycloferromagnetic nanocomposite material.

[0007] Technical solution: In order to achieve the above objectives, the present invention provides an immobilized tetraamide-hexamethylphenylcycloferromagnetic nanocomposite material, comprising hexadecyltrimethylammonium bromide and tetraamide-hexamethylphenylcycloferromagnetic nanocomposite material.

[0008] The molar ratio of hexadecyltrimethylammonium bromide to tetraamide hexamethylphenylcycloferric iron is 25:1.8-2.2.

[0009] Preferably, the molar ratio of hexadecyltrimethylammonium bromide to tetraamide hexamethylphenylcycloferric is 25:2.

[0010] This invention provides a method for synthesizing immobilized tetraamide-hexamethylphenylcycloferromagnetic nanocomposites. The synthesis method utilizes a surfactant-assisted self-assembly (SAS) approach and specifically includes the following steps:

[0011] (a) Slowly add surfactant to deionized water;

[0012] (b) Place the surfactant solution from step (a) in a constant temperature water bath and stir, then add FeCl3 and FeCl2 solutions;

[0013] (c) Then, a solution of tetramethylphenylcycloferric chloride and excess ammonia are injected sequentially to react and obtain a magnetic composite material.

[0014] (d) The magnetic composite material obtained in (c) was cooled to room temperature, the supernatant was removed, the solid was washed with deionized water, and dried under vacuum to obtain the tetraamide-hexamethylphenylcycloferromagnetic composite material (Fe(III)-TAML / CTAB@Fe3O4).

[0015] The surfactant mentioned in step (a) is hexadecyltrimethylammonium bromide (CTAB), and its concentration dissolved in the deionized water is 20-25 mM.

[0016] In step (b), the final concentrations of the FeCl3 and FeCl2 solutions are 0.3-0.4M and 0.2-0.3M, respectively, and the molar ratio of the surfactant (CTAB) to FeCl3 and FeCl2 is 0.5-1:4:1.5-2.5.

[0017] In step (c), the final concentration of the tetraamide hexamethylphenylcycloferric solution is 21.5-2.5 mM, so that the concentration of tetraamide hexamethylphenylcycloferric in the mixed solution is in the range of 100-200 μM, and the concentration of ammonia is 20-30%.

[0018] Further, the surfactant mentioned in step (a) is hexadecyltrimethylammonium bromide (CTAB), dissolved in the deionized water at a concentration of 25 mM.

[0019] Further, in step (b), the final concentrations of the FeCl3 and FeCl2 solutions are 0.4M and 0.2M, respectively, and the molar ratio of the surfactant (CTAB) to FeCl3 and FeCl2 is 1:4:2.

[0020] Further, the final concentration of the tetraamide-hexamethylphenylcycloferric solution in step (c) is 2 mM, so that the concentration of tetraamide-hexamethylphenylcycloferric (Fe(III)-TAML) in the mixed solution is in the range of 100-200 μM, and the ammonia concentration is 25%.

[0021] Further, the absorbance of Fe(III)-TAML loaded on the magnetic nanomaterial synthesized in step (d) was measured at 366 nm using a UV spectrophotometer (molar absorptivity of 6600 Mn). - 1 cm -1 The loading of Fe(III)-TAML on magnetite was calculated by the difference method.

[0022] This invention also provides the application of immobilized tetraamide-hexamethylphenylcycloferromagnetic nanocomposite material in the degradation of bisphenol compounds.

[0023] Furthermore, the application process is as follows: the synthesized tetraamide-hexamethylphenylcycloferromagnetic composite material is dispersed in an aqueous solution containing bisphenol compounds, and hydrogen peroxide is added to carry out a degradation reaction.

[0024] Furthermore, the pH environment for degrading bisphenol compounds is 7–10.

[0025] Preferably, use of the immobilized tetraamido macrocyclic ligand iron magnetic nanocomposite in the field of sewage treatment containing bisphenol compounds.

[0026] The present invention synthesizes a Fe(III)-TAML magnetic composite material through a SAS method. The composite material generates high-valent iron ligands with strong oxidizing property under peroxide activation, can achieve rapid degradation of bisphenol compounds, and can exist stably in air and aqueous solutions. Under alkaline conditions, Fe(III)-TAML is first oxidized by peroxide to form high-valent iron complexes (namely Fe(IV)-TAML and Fe(V)-TAML), which then oxidize bisphenol compounds. The magnetic composite material still maintains good degradation activity after being reused for more than four times, solves the problems existing in the prior art that Fe(III)-TAML has low utilization rate, high cost, cannot be reused, and the catalytic activity has strong pH dependence, and achieves the purpose of environmental friendliness.

[0027] The principle of the present invention is as follows: the protonation state of each component in the system depends on the pH value of the solution, and meanwhile determines the generation of oxidized Fe(III)-TAML and the degradation of pollutants. As shown in formulas (1) to (6), TAML acts as an electron donor and hydrogen peroxide acts as an electron acceptor during the generation of reaction intermediates, [Fe(III)-TAML(OH)] 2- compared with [Fe(III)-TAML(OH2)] - , the former has higher electron cloud density and is a better electron donor, therefore k2>>k1; similarly, molecular H2O2 has lower electron cloud density and is a better electron acceptor, that is k4<k2. When pH increases, on one hand [Fe(III)-TAML(OH)] 2- increases, which promotes the reaction; on the other hand, HO2 - also increases, which is unfavorable for the reaction. It has been reported in the literature that the pK a of Fe(III)-TAML is about 10, and the pK a of H2O2 is about 11, therefore the catalytic efficiency of Fe(III)-TAML is the highest when pH is in the range of 10 to 11. In the present invention, Fe(III)-TAML is successfully loaded on magnetite with the assistance of a surfactant, and the material still has a good degradation effect under the condition of pH=7, which is a novel environment-friendly material. The reusability of the material also proves that the surfactant reduces the leaching of Fe(III)-TAML. The synthesized material has strong magnetism and is easy to separate, which provides feasibility for practical reuse.

[0028]

[0029]

[0030]

[0031]

[0032]

[0033]

[0034] The magnetic composite material prepared by this invention can be directly separated from the reaction solution by magnetic adsorption, achieving the purpose of reuse and further promoting the promotion and application of Fe(III)-TAML, ultimately reducing the overall cost. The magnetic composite material prepared by this invention successfully loads Fe(III)-TAML onto magnetite with the assistance of a specific surfactant, and also exhibits good degradation performance under pH=7 conditions, making it a novel environmentally friendly material. The reusability of the material also proves that the specific surfactant of this invention reduces the leaching of Fe(III)-TAML and improves the utilization rate of Fe(III)-TAML. The synthesized material has strong magnetism and is easy to separate, providing feasibility for practical reuse.

[0035] Beneficial effects: Compared with the prior art, the present invention has the following advantages:

[0036] (1) The magnetic nanocomposite material of the present invention has a short synthesis time and mild reaction conditions, simple operation, reduced preparation cost, improved Fe(III)-TAML utilization rate, and can be used to degrade various persistent aromatic organic pollutants, which is conducive to promotion and application.

[0037] (2) The magnetic nanocomposite material prepared by the present invention rapidly adsorbs BPA in the solution within 10s, and the adsorption of BPA reaches more than 90% after 120s. This overcomes the problems of low utilization rate, high cost, inability to be reused, and strong pH dependence of catalytic activity of the existing Fe(III)-TAML.

[0038] (3) The magnetic nanocomposite material prepared by the present invention improves the degradation activity of the composite material by doping Fe(III)-TAML in magnetite, and can avoid the pollution caused by excessive Fe(III)-TAML entering the environment. At pH 10, it can reach 100% degradation rate within 2 minutes, and the degradation process is very efficient. At pH 7, BPs can reach a degradation rate of more than 75% within 60 minutes. Among them, BPAP, BPZ and TMBPA even reach 100% degradation rate, realizing efficient degradation in a neutral environment.

[0039] (4) The magnetic nanocomposite material prepared by the present invention can be reused, enabling bisphenol compounds to be reused at least four times. The first three rounds achieve 100% degradation within 20 minutes. Among them, the degradation efficiency of BPA in the first four rounds can be maintained at 100%, which proves that the synthesized material has good recyclability and reusability.

[0040] (5) The nanomaterial FeIII-TAML / CTAB@Fe3O4 prepared in this invention is a novel environmentally friendly material with strong magnetism, which can be separated from the solution by a magnet. Furthermore, this material can achieve efficient degradation of bisphenol A; in a homogeneous aqueous solution, its degradation rate is close to that of FeIII-TAML. The reusability of the material also demonstrates that the surfactant reduces the leaching of Fe(III)-TAML. The synthesized material is strongly magnetic and easy to separate, providing feasibility for practical reuse. Attached Figure Description

[0041] Figure 1 This is the synthesis route for the Fe(III)-TAML / CTAB@Fe3O4 magnetic nanomaterials of this invention;

[0042] Figure 2 For the magnetic verification of the synthesized materials of this invention, number ① is Fe(III)-TAML / CTAB@Fe3O4, number ② is CTAB@Fe3O4, number ③ is Fe3O4, and number ④ is Fe(III)-TAML@Fe3O4;

[0043] Figure 3 The results are transmission electron microscopy (TEM) and particle size analysis of the synthesized materials of this invention. (a) and (e) are Fe3O4, (b) and (f) are Fe(III)-TAML@Fe3O4, (c) and (g) are CTAB@Fe3O4, and (d) and (h) are Fe(III)-TAML / CTAB@Fe3O4.

[0044] Figure 4 The XRD diffraction pattern of the synthesized material of this invention;

[0045] Figure 5 The XPS results for the synthesized materials of this invention are shown in (a) to (d), which are the peak separation results of Fe(III)-TAML / CTAB@Fe3O4, and (e) and (f) are the peak separation results of Fe3O4. Among them, (a) and (e) are the characteristic spectra of Fe 2p, (b) and (f) are the characteristic spectra of O1s, (c) is the characteristic spectra of C1s, and (d) is the characteristic spectra of N1s.

[0046] Figure 6 The FT-IR results are for the materials synthesized in this invention;

[0047] Figure 7 The degradation rates of seven bisphenol compounds under H2O2 catalysis by magnetic nanomaterials were measured when the pH environment for the degradation of bisphenol compounds was 10, according to the present invention.

[0048] Figure 8 The degradation rates of seven bisphenol compounds under H2O2 catalysis by magnetic nanomaterials were measured when the pH environment was 7, according to the present invention.

[0049] Figure 9 This is the adsorption isotherm of BPA by the magnetic nanomaterials of this invention, Q. e The equilibrium adsorption amount at adsorption equilibrium is expressed in μM; C e The concentration of the solute remaining in the solution when the reaction reaches equilibrium, in μM;

[0050] Figure 10 To illustrate the adsorption kinetics of BPA on the magnetic nanomaterials of this invention, Q e Q represents the equilibrium adsorption amount at adsorption equilibrium, in μM; t The adsorption amount at time t, in μM;

[0051] Figure 11 This invention provides an experiment demonstrating the reusability of the magnetic nanomaterials used to degrade BPA.

[0052] Figure 12 This experiment demonstrates the reusability of the magnetic nanomaterials used in this invention to degrade BPAP. Detailed Implementation

[0053] The present invention will be further described below with reference to specific embodiments.

[0054] Fe(III)-TAML / CTAB@Fe3O4 is a magnetic nanomaterial of Fe(III)-TAML supported on Fe3O4 with the surfactant CTAB. CTAB@Fe3O4 is a magnetic nanomaterial of Fe3O4 supported on Fe3O4 with the surfactant CTAB. Fe3O4 is a synthetic magnetite.

[0055] CTAB: hexadecyltrimethylammonium bromide; Fe(III)-TAML: tetraamidohexamethylphenylcycloferric (GreenOx catalyst, provided by Mellon Institute, Pittsburgh, PAN, USA, A, Sijia Liang, et al. "Rapid destruction of triclosan by Iron(III)-Tetraamidomacrocyclic ligand / hydrogenperoxide system." Chemosphere 261 (2020).).

[0056] Example 1

[0057] The steps for characterizing the appearance morphology of the synthesized material for degrading bisphenol compounds are as follows:

[0058] (1) As Figure 1 As shown, surfactant CTAB was slowly added to deionized water until fully dissolved, resulting in CTAB (25 mM, 0.4 L). The mixture was then placed in a 60°C constant-temperature water bath and mechanically stirred. Pre-dissolved FeCl3 (0.4 M, 0.1 L) and FeCl2 (0.2 M, 0.1 L) solutions in a 2:1 molar ratio were then added. After heating to 60°C, a pre-dissolved Fe(III)-TAML (2 mM, 0.05 L) solution and excess ammonia (25%, 0.04 L) were added sequentially. The reaction was carried out at a constant temperature of 60°C for 1 hour to obtain the magnetic composite material.

[0059] (2) Cool the magnetic composite material obtained in step (1) to room temperature, remove the supernatant, wash the solid with deionized water five times, remove most of the water by vacuum drying at 40°C, freeze-dry and grind to obtain Fe(III)-TAML / CTAB@Fe3O4 magnetic composite material.

[0060] (3) The surfactant CTAB was slowly added to deionized water to dissolve it completely, resulting in CTAB (25 mM, 0.4 L). The mixture was then placed in a 60°C constant temperature water bath and, under mechanical stirring, FeCl3 (0.4 M, 0.1 L) and FeCl2 (0.2 M, 0.1 L), which had been dissolved in deionized water beforehand, were injected. The mixture was reacted at 60°C for 1 h. The CTAB@Fe3O4 magnetic composite material was synthesized by loading it onto magnetite using the method described in step (2). Similarly, Fe(III)-TAML (2 mM, 0.05 L) solution, FeCl3 (0.4 M, 0.1 L) solution, FeCl2 (0.2 M, 0.1 L) solution, and ammonia (25% by mass, 0.04 L) solution were slowly added to 0.4 L of deionized water. The mixture was reacted at 60°C for 1 h. The Fe(III)-TAML@Fe3O4 magnetic composite material was synthesized by loading it onto magnetite using the method described in step (2). In addition, pure magnetite was synthesized by slowly adding FeCl3 (0.4M, 0.1L) and FeCl2 (0.2M, 0.1L) solutions to 0.4L deionized water, heating to 60°C, and then adding ammonia (25%, 0.04L). The reaction was carried out at a constant temperature of 60°C for 1 hour, and Fe3O4 material was obtained using the method described in step (2) above. The four materials were then transferred from the mortar and placed in a dry glass bottle for sealed storage.

[0061] (4) Use a strong magnet to verify the magnetism of the synthesized material, such as Figure 2 All four materials are strongly magnetic and can be easily separated from aqueous solutions. Material ①Fe(III)-TAML / CTAB@Fe3O4 and material ②CTAB@Fe3O4 are brownish-black, while material ③Fe3O4 and material ④Fe(III)-TAML@Fe3O4 are pure black.

[0062] (5) The external structure of the material was observed using a transmission electron microscope (TEM, Tecnai F20) manufactured by FEI Corporation, USA, such as... Figure 3 As shown, the polycrystalline rings exhibit a core-shell structure, Fe3O4 ( Figure 3 a) and Fe(III)-TAML@Fe3O4 ( Figure 3 b) It has a clear polygonal lattice configuration, with overlapping and interlaced crystal parts, and side lengths ranging from 8 to 15 nm. Figure 3 Compared to ac, FeIII-TAML / CTAB@Fe3O4 ( Figure 3The blurred edges in d) demonstrate the successful loading of FeIII-TAML, consistent with the results from the UV-Vis spectrophotometer. However, the loading of FeIII-TAML on Fe3O4 is negligible without CTAB, explaining the similarity in properties between Fe3O4 and Fe(III)-TAML@Fe3O4. Therefore, the successful loading of FeIII-TAML on Fe3O4 must be achieved with the participation of CTAB. Since NH3-H2O was used in the preparation of magnetite, the OH- in the system increases the negative charge on the magnetite surface, creating electrostatic repulsion with the negatively charged FeIII-TAML. Therefore, the positively charged CTAB can connect magnetite and FeIII-TAML during the material synthesis process, forming FeIII-TAML / CTAB@Fe3O4.

[0063] (6) The particle size of the four synthesized materials was characterized using a laser particle size analyzer (ZEN 3500 Zetasizer Nano ZS). The magnetic material was dispersed in an aqueous solution at a concentration of 100 mg / L. The pH was adjusted to 7.0 using 0.1 M NaOH and HClO4 solutions. 1 mL of the well-mixed solution was added to a U-shaped capillary cuvette to determine the particle size. The refractive index was set to 3.000, the sample equilibrium temperature was set to 25℃, and the equilibrium time was 60 s. The particle size data were measured three times consecutively. Figure 3 (e)~(h) The particle size range of Fe3O4 and Fe(III)-TAML@Fe3O4 materials is mainly distributed in the range of 400~1000nm, the particle size range of CTAB@Fe3O4 is mainly distributed in the range of 70~200nm, and the particle size range of Fe(III)-TAML / CTAB@Fe3O4 is mainly distributed in the range of 60~120nm.

[0064] (7) X-ray diffraction (XRD, D8 Advance) analysis was performed to determine the crystal structure of the synthesized material. The four synthesized powder samples were analyzed on a single-crystal silicon sample stage with a working voltage of 40 kV and a working current of 40 mA. The 2θ angle range was measured from 10 to 80°, with a scan step size of 0.02° and a scan rate of 0.2° / s. The results are as follows: Figure 4 As shown, the peaks at 2θ values ​​of 30°, 33°, 36°, 43°, 57°, and 63° correspond to the {220}, {311}, {222}, {400}, {511}, and {440} crystal planes of magnetite, respectively, proving that all the iron minerals synthesized in this work are magnetite and do not contain impurities of other crystal forms.

[0065] (8) The above results confirm that the successful loading of FeIII-TAML onto Fe3O4 should be achieved with the participation of CTAB. Since NH3-H2O was used in the preparation of magnetite, the OH- in the system increased the negative charge on the magnetite surface, resulting in electrostatic repulsion with the negatively charged FeIII-TAML. Therefore, the positively charged CTAB can connect magnetite and FeIII-TAML during the material synthesis process, forming FeIII-TAML / CTAB@Fe3O4. Fe(III)-TAML alone cannot achieve successful loading onto Fe3O4; therefore, this material is not used for subsequent implementation.

[0066] Example 2

[0067] The chemical characterization steps for synthesizing materials for degrading bisphenol compounds are as follows:

[0068] (1) The surfactant CTAB was slowly added to deionized water until it was fully dissolved, resulting in CTAB (25 mM, 0.4 L). The mixture was then placed in a 60°C constant temperature water bath and mechanically stirred. FeCl3 (0.4 M, 0.1 L) and FeCl2 (0.2 M, 0.1 L) solutions, which had been dissolved in deionized water in a molar ratio of 2:1, were then added. After heating to 60°C, Fe(III)-TAML (2 mM, 0.05 L) solution and ammonia (25%, 0.04 L) that had been dissolved in deionized water in advance were added sequentially. The mixture was reacted at a constant temperature of 60°C for 1 h.

[0069] (2) The obtained magnetic composite material was cooled to room temperature, the supernatant was removed, the solid was washed five times with deionized water, and most of the water was removed by vacuum drying at 40°C. After freeze drying and grinding, Fe(III)-TAML / CTAB@Fe3O4 magnetic composite material was obtained.

[0070] (3) The surfactant CTAB was slowly added to deionized water until it was fully dissolved, resulting in CTAB (25 mM 0.4 L). The mixture was then placed in a 60°C constant temperature water bath and, under mechanical stirring, FeCl3 (0.4 M, 0.1 L) and FeCl2 (0.2 M, 0.1 L), which had been dissolved in deionized water beforehand, were injected. The mixture was reacted at 60°C for 1 h. The CTAB@Fe3O4 magnetic composite material was synthesized by loading it onto magnetite using the method described in step (2). In addition, pure magnetite was synthesized by slowly adding FeCl3 (0.4 M, 0.1 L) solution and FeCl2 (0.2 M, 0.1 L) solution to 0.4 L of deionized water. After heating to 60°C, ammonia water (25%, 0.04 L) was added. The mixture was reacted at 60°C for 1 h. Fe3O4 material was obtained using the method described in step (2). The three materials were then transferred from the mortar and placed in a dry glass bottle for sealed storage.

[0071] (4) The energy spectrum was characterized using an X-ray photoelectron spectroscopy (XPS, PHI 5000 VersaProbe) to determine the elemental composition, chemical state, and molecular structure of the synthesized magnetic material. The obtained data were processed using Avantage software to obtain peaks for Fe, O, C, and N, such as... Figure 5 Comparing the characteristic peak diagrams of pure Fe3O4, it can be determined that the synthesized Fe(III)-TAML / CTAB@Fe3O4 magnetic nanomaterial is magnetite. The detected phenolic hydroxyl and -C=C- structures confirm successful loading of Fe(III)-TAML, but due to the low loading amount, its proportion is not significant. In fact, as a catalyst, more Fe(III)-TAML is better within a certain range, but beyond a certain concentration, more is not necessarily better. CTAB has an ultra-long carbon chain, and -CC- and N signals can also be found in the characteristic spectra of C1s and N1s, proving that CTAB successfully assisted in the self-assembly synthesis of the target material.

[0072] (5) The functional groups of the material were characterized using Fourier transform infrared spectroscopy (FT-IR, Vertex 70V), with the scanning wavenumber range set to 600–4000 cm⁻¹. -1 10×10 points, 100 scans, such as Figure 6 750cm -1 The following infrared absorption bands reflect the Fe-O stretching vibration. CTAB@Fe3O4 in the range of 2800–2880 cm⁻¹ -1The absorption band belongs to the stretching vibration of CH. The peak broadening in the 1380–1500 cm⁻¹ region is due to the combined effect of the CN stretching vibration and the CH bending vibration, proving that CTAB is loaded onto magnetite. The Fe(III)-TAML / CTAB@Fe₃O₄ structure has a benzene ring and a carbonyl group, and the peak in the 1700–1820 cm⁻¹ region is due to the stretching vibration of CH. -1 The presence of C=C stretching vibrations and C=O stretching vibrations of the benzene ring proves that Fe(III)-TAML is loaded onto the magnet material, but the results are not very significant due to the limited loading amount.

[0073] (6) The infrared and XPS spectra illustrate the synthesis of the material, and the results consistently show that CTAB-assisted Fe(III)-TAML was successfully loaded on Fe3O4.

[0074] Example 3

[0075] A method for synthesizing magnetic nanomaterial Fe(III)-TAML / CTAB@Fe3O4 and using it for the degradation of bisphenol compounds, comprising the following steps:

[0076] (1) The surfactant CTAB was slowly added to deionized water until it was fully dissolved, resulting in CTAB (25 mM, 0.4 L). The mixture was then placed in a 60°C constant temperature water bath and mechanically stirred. FeCl3 (0.4 M, 0.1 L) and FeCl2 (0.2 M, 0.1 L) solutions, which had been dissolved in deionized water in a molar ratio of 2:1, were then added. After heating to 60°C, Fe(III)-TAML (2 mM, 0.05 L) solution, which had been dissolved in deionized water in advance, and excess ammonia (25%, 0.04 L) were added sequentially. The mixture was reacted at a constant temperature of 60°C for 1 h.

[0077] (2) The obtained magnetic composite material was cooled to room temperature, the supernatant was removed, the solid was washed five times with deionized water, and most of the water was removed by vacuum drying at 40°C. After freeze drying and grinding, Fe(III)-TAML / CTAB@Fe3O4 magnetic composite material was obtained.

[0078] (3) The surfactant CTAB was slowly added to deionized water to dissolve it completely, resulting in CTAB (25 mM 0.4 L). The mixture was then placed in a 60°C constant temperature water bath and, under mechanical stirring, FeCl3 (0.4 M, 0.1 L) and FeCl2 (0.2 M, 0.1 L), which had been dissolved in deionized water beforehand, were injected. The mixture was reacted at 60°C for 1 h. The CTAB@Fe3O4 magnetic composite material was synthesized by loading it onto magnetite using the method described in step (2). In addition, pure magnetite was synthesized by slowly adding FeCl3 (0.4 M, 0.1 L) and FeCl2 (0.2 M, 0.1 L) solutions to 0.4 L of deionized water. After heating to 60°C, ammonia (25%, 0.04 L) was added. The mixture was reacted at 60°C for 1 h. Fe3O4 material was obtained using the method described in step (2). The three materials were then transferred from the mortar and placed in a dry glass bottle for sealed storage.

[0079] (4) The conditions for degrading BPs are as follows: The absorbance of Fe(III)-TAML loaded on the synthesized magnetic nanomaterials at 366 nm was measured by ultraviolet spectrophotometer (molar absorptivity was 6600 M). -1 cm -1 The residual amount of Fe(III)-TAML in the supernatant was calculated. The loading of Fe(III)-TAML on magnetite was calculated by difference. The mass of Fe(III)-TAML / CTAB@Fe3O4 added was converted to make the Fe(III)-TAML concentration 1.0 μM; the concentration of BPs added 10.0 μM; the concentration of buffer salt 20 mM; and the concentration of H2O2 1.0 mM. The degradation kinetics of seven common BPs (BPA, BPBA, BPE, BPZ, BPC, TBBPA, TMBPA) were investigated under pH 10 and pH 7 conditions. The synthesized CTAB@Fe3O4 (concentration 1.0 μM) and Fe3O4 (concentration 1.0 μM) materials were used as control materials. The degradation rate at pH 10 is as follows. Figure 7 Of the seven biochemical enzymes selected, all except TBBPA achieved 100% degradation within 2 minutes, demonstrating highly efficient degradation. TBBPA also achieved 100% degradation within 5 minutes. The degradation rate at pH 7 was as follows: Figure 8 All seven BPs achieved a degradation rate of over 75% within 60 minutes, with BPAP, BPZ, and TMBPA achieving a degradation rate of 100%, demonstrating efficient degradation in a neutral environment.

[0080] Example 4

[0081] The adsorption process of BPA by three magnetic nanomaterials at pH 10 was investigated, and the steps were as follows:

[0082] (1) The surfactant CTAB was slowly added to deionized water until it was fully dissolved, resulting in CTAB (25 mM, 0.4 L). The mixture was then placed in a 60°C constant temperature water bath and mechanically stirred. FeCl3 (0.4 M, 0.1 L) and FeCl2 (0.2 M, 0.1 L) solutions, which had been dissolved in deionized water in a molar ratio of 2:1, were then added. After heating to 60°C, Fe(III)-TAML (2 mM, 0.05 L) solution, which had been dissolved in deionized water in advance, and excess ammonia (25%, 0.04 L) were added sequentially. The mixture was reacted at a constant temperature of 60°C for 1 h.

[0083] (2) The obtained magnetic composite material was cooled to room temperature, the supernatant was removed, the solid was washed five times with deionized water, and most of the water was removed by vacuum drying at 40°C. After freeze drying and grinding, Fe(III)-TAML / CTAB@Fe3O4 magnetic composite material was obtained.

[0084] (3) The surfactant CTAB was slowly added to deionized water until it was fully dissolved, resulting in CTAB (25 mM 0.4 L). The mixture was then placed in a 60°C constant temperature water bath and mechanically stirred. FeCl3 (0.4 M, 0.1 L) solution and FeCl2 (0.2 M, 0.1 L) solution, which had been dissolved in deionized water beforehand, were then injected. The mixture was reacted at 60°C for 1 h. The CTAB@Fe3O4 magnetic composite material was synthesized by loading it onto magnetite using the method described in step (2). In addition, pure magnetite was synthesized by slowly adding FeCl3 (0.4 M, 0.1 L) and FeCl2 (0.2 M, 0.1 L) solutions to 0.4 L of deionized water. After heating to 60°C, ammonia (25%, 0.04 L) was added. The mixture was reacted at 60°C for 1 h. Fe3O4 material was obtained using the method described in step (2). The three materials were then transferred from the mortar and placed in a dry glass bottle for sealed storage.

[0085] (4) Adsorption isotherm experimental conditions: BPA concentrations were 3.0, 5.0, 7.0, 10.0, 20.0, 40.0, and 80.0 μM; the dosage of Fe(III)-TAML / CTAB@Fe3O4 material was calculated based on a Fe(III)-TAML concentration of 1.0 μM, and the dosage of CTAB@Fe3O4 and Fe3O4 materials remained consistent; pH = 10; isothermal shaking time was 24 h. The adsorption amount was obtained by the difference between the concentrations before and after adsorption, as shown below. Figure 9The fitting results show that both the Langmiur (solid line fitting) and Freundlich (dashed line fitting) adsorption isotherm models have extremely high fitting accuracy. The adsorption capacity of the three magnetic nanomaterials is CTAB@Fe3O4 > Fe(III)-TAML / CTAB@Fe3O4 > Fe3O4. Although the adsorption capacity of Fe(III)-TAML / CTAB@Fe3O4 is not as high as that of CTAB@Fe3O4, its degradation rate is very high. Figure 7 and Figure 8 It has been proven that it can efficiently degrade organic pollutants in the environment.

[0086] (5) Adsorption kinetics experimental conditions: Initial BPA concentration 10.0 μM; Fe(III)-TAML / CTAB@Fe3O4 material dosage was calculated based on a Fe(III)-TAML concentration of 1.0 μM, and the dosage of CTAB@Fe3O4 and Fe3O4 materials remained consistent; pH = 10; t = 0, 10, 20, 30, 40, 50, 60, 90, 120 s. The percentage of BPA adsorbed on the three magnetic nanomaterials at different reaction times relative to the equilibrium adsorption was calculated, and the results are as follows: Figure 10 As shown, upon addition, the three materials rapidly adsorbed BPA from the solution within 10 seconds. At 10 seconds, the adsorption of BPA by Fe3O4, CTAB@Fe3O4, and Fe(III)-TAML / CTAB@Fe3O4 reached 67.24%, 85.33%, and 61.62% of their equilibrium adsorption capacities, respectively. After 120 seconds, the adsorption of BPA by the three materials reached 96.67%, 90.13%, and 73.67% of their equilibrium adsorption capacities, respectively. This indicates that the degradation reaction occurs after adsorption, and the degradation reaction takes place at the molecular surface, not in solution. Adsorption is beneficial to degradation, and Fe(III)-TAML / CTAB@Fe3O4 has the highest adsorption capacity at equilibrium, thus promoting the fastest degradation rate.

[0087] Example 5

[0088] The procedure for determining the reusability of the material for BPA and BPAP at pH 10 is as follows:

[0089] (1) Slowly add surfactant CTAB to deionized water until it is fully dissolved, resulting in CTAB (25 mM, 0.4 L). Then, place the mixture in a 60°C constant temperature water bath and, with mechanical stirring, inject FeCl3 (0.4 M, 0.1 L) and FeCl2 (0.2 M, 0.1 L) solutions, which were previously dissolved in deionized water in a molar ratio of 2:1. After heating to 60°C, sequentially inject Fe(III)-TAML (2 mM, 0.05 L) solution, which was previously dissolved in deionized water, and excess ammonia (25%, 0.04 L). React at a constant temperature of 60°C for 1 h.

[0090] (2) The obtained magnetic composite material was cooled to room temperature, the supernatant was removed, the solid was washed five times with deionized water, and most of the water was removed by vacuum drying at 40°C. After freeze drying and grinding, Fe(III)-TAML / CTAB@Fe3O4 magnetic composite material was obtained.

[0091] (3) The degradation conditions were as follows: The loading was calculated using a UV spectrophotometer to reduce the amount of Fe(III)-TAML / CTAB@Fe3O4 added, resulting in a Fe(III)-TAML concentration of 1.0 μM; a BP concentration of 10.0 μM; pH = 10; H2O2 concentration of 1.0 mM / L; and t = 0, 0.5, 1, 3, 5, 10, 20, 30, and 60 min. After one round of degradation, Fe(III)-TAML / CTAB@Fe3O4 was separated from the aqueous solution using a strong magnetic magnet, washed three times with deionized water, and then the same concentration of buffer salt solution, BP mother liquor, and H2O2 were added. The experiment was repeated for five cycles. The reusability results of BPA are as follows: Figure 11 The reusability results of BPAP are as follows: Figure 12 In the first three rounds, both bisphenols achieved 100% degradation within 20 minutes. BPA maintained 100% degradation efficiency in the fourth round, and 52.71% in the fifth round. In contrast, the efficiencies of BPAP in the fourth and fifth rounds were 87.13% and 42.68%, respectively, demonstrating that the synthesized material has good recyclability and reusability, and can be reused at least four times. However, the Fe(III)-TAML / DODMA composite material prepared by the method of this invention (CTAB replaces DODMA and does not contain Fe3O4) cannot be reused, and the synthesized material is not easily separated.

Claims

1. An application of a magnetic nanocomposite material in the degradation of bisphenol compounds; the application process is as follows: dispersing the synthesized immobilized tetraamide-hexamethylphenylcycloferromagnetic composite material in an aqueous solution containing bisphenol compounds, and adding hydrogen peroxide to carry out a degradation reaction; the pH environment for degrading bisphenol compounds is 10; the bisphenol compounds include BPA, BPE, BPZ, BPC, TBBPA, and TMBPA; the synthesis method of the immobilized tetraamide-hexamethylphenylcycloferromagnetic nanocomposite material includes the following steps: (a) Slowly add a surfactant to deionized water; (b) Place the surfactant solution from step (a) in a constant temperature water bath and stir, then add FeCl3 and FeCl2 solutions; (c) Then, a solution of tetraamide-hexamethylphenylcycloferric oxide and ammonia water are injected sequentially to react and obtain a magnetic composite material; (d) The magnetic composite material obtained in (c) is cooled to room temperature, the supernatant is removed, washed with deionized water, and dried under vacuum to obtain the immobilized tetraamide-hexamethylphenylcycloferromagnetic composite material; the surfactant in step (a) is hexadecyltrimethylammonium bromide; the molar ratio of hexadecyltrimethylammonium bromide to tetraamide-hexamethylphenylcycloferromagnetic composite material is 25:1.8-2.

2.

2. The application according to claim 1, characterized in that, In step (a), the concentration of hexadecyltrimethylammonium bromide dissolved in the deionized water is 20-25 mM.

3. The application according to claim 1, characterized in that, In step (b), the final concentrations of the FeCl3 and FeCl2 solutions are 0.3-0.4 M and 0.2-0.3 M, respectively, and the molar ratio of the surfactant, FeCl3, and FeCl2 is 0.5-1:4:1.5-2.

5.

4. The application according to claim 1, characterized in that, The concentration of the tetraamide hexamethylphenylcycloferric solution in step (c) is 1.5-2.5 mM, so that the concentration of tetraamide hexamethylphenylcycloferric in the mixed solution is in the range of 100-200. μ M, ammonia concentration is 20-30%.

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