UiO-66 / macroporous resin composite material, preparation method and application

Abstract

The application provides a UiO-66 / macroporous resin composite material, a preparation method and application, and relates to the technical field of water pollutant treatment materials.The method comprises the following steps: dissolving zirconium tetrachloride and sorbitol in N,N-dimethylformamide to obtain a precursor solution; after macroporous resin is cleaned and replaced, the macroporous resin is added to the precursor solution for soaking, then terephthalic acid and deionized water are added for hydrothermal reaction, and finally a UiO-66 / macroporous resin composite material is obtained.The application combines UiO-66 with excellent water stability and macroporous resin to construct a composite adsorption system which is stable in structure, rich in pores and has synergistically enhanced functional sites, so that the problems of poor dispersibility of UiO-66, easy formation of large crystal agglomerates and easy plugging of resin pores in the existing UiO-66 and macroporous resin composite process can be effectively overcome, the targeted adsorption performance of the composite material on antibiotics is effectively improved, and the long-term cyclic stability is improved.

Description

Technical Field

[0001] This invention relates to the field of water pollutant treatment materials, and in particular to a UiO-66 / macroporous resin composite material, its preparation method, and its application. Background Technology

[0002] Antibiotics are widely recognized as one of the most important emerging environmental pollutants. Their greatest environmental risk lies not in their direct toxicity, but in the generation and spread of antibiotic resistance genes.

[0003] Traditional methods for treating antibiotic wastewater include extraction, chemical oxidation, biological methods, and adsorption. Extraction methods face challenges such as difficulty in selecting extraction solvents, unsatisfactory separation effects, and limited effectiveness in treating complex water bodies. Chemical oxidation methods suffer from high reagent costs, potential for toxic byproducts, and their efficiency is heavily dependent on the background water quality, resulting in poor adaptability. Biological methods offer low wastewater treatment costs, broad bacterial selection, and do not require large amounts of chemical reagents, resulting in environmental friendliness and no secondary pollution. However, they suffer from long biological cultivation cycles and poor performance in treating water bodies with extreme conditions.

[0004] To avoid the shortcomings of traditional methods, adsorption is a viable option. This method offers advantages such as low energy consumption, simple and convenient operation, low operating costs, and minimal secondary pollution. In recent years, metal-organic frameworks (MOFs) have been used to remove organic pollutants from aqueous solutions, demonstrating significant adsorption capacity in laboratory settings. However, their application as pollutant absorbents on a practical scale still faces several challenges: many early or common MOFs exhibit poor water stability; water molecules hydrolyze the coordination bonds between the metal and organic ligands, causing their crystal structure to collapse and resulting in the loss of their porous structure and specific functions (such as adsorption). This poses a significant obstacle to their application in humid or aquatic environments.

[0005] The UiO-66 series is one of the most stable MOF materials known to date. It uses zirconium metal clusters as inorganic nodes and terephthalic acid and its derivatives as organic linkers, and is assembled through coordination bonds. It can maintain high stability at high temperatures (such as 500℃), and its water stability is far superior to many early MOFs based on zinc, copper and other materials.

[0006] Chinese patent document CN116440957A discloses a UiO-66 / ZnO composite material, its preparation method, and its applications. The method involves dispersing ZnO and ZrCl4 in an N,N-dimethylamide solution and dissolving them by magnetic stirring at room temperature; slowly adding terephthalic acid to the resulting mixture while continuously stirring at room temperature until dissolved; pouring the resulting mixture into a reaction vessel lined with polytetrafluoroethylene for hydrothermal reaction; filtering, washing, and vacuum drying the resulting reactants to obtain the UiO-66 / ZnO composite material. However, the ZnO used in this method has low solubility in the DMF system, resulting in poor controllability of reaction activity, leading to ZnO agglomeration or Zr component precipitation. ZnO undergoes partial dissolution or recrystallization after participating in the reaction, affecting uniformity and specific surface area.

[0007] Chinese patent document CN104785210A discloses a polyamine-modified UiO-66 composite adsorbent capable of purifying trace amounts of phosphorus and arsenic in water, and its preparation method. This method involves dissolving a polyamine compound in a solvent, adding an organometallic framework UiO-66, and allowing it to dissolve and react to prepare the polyamine-modified UiO-66 composite adsorbent. However, this method is complex and requires stringent process conditions, directly increasing the time and energy consumption of material preparation, which is not conducive to large-scale industrial production. Furthermore, a common phenomenon with amino-functionalized UiO-66 materials is a decrease in specific surface area and porosity. Studies have shown that with the introduction of amino groups, the specific surface area and total porosity of the material usually decrease; this is mainly because the amino functional groups themselves occupy a certain space (steric hindrance effect), and the modification process may lead to a decrease in the crystallinity of the material; while the reduction in specific surface area usually means a reduction in the physical space available for pollutant adhesion.

[0008] Patent document CN108855010B discloses the application of a UiO-66 / polyaromatic amine composite material in the treatment of wastewater containing hexavalent Cr. The UiO-66 / polyaromatic amine composite material is prepared by in-situ chemical oxidative polymerization of aromatic amine monomers on the surface of UiO-66. However, this composite material has a narrow applicable pH range, mainly suitable for acidic conditions (pH 1-5, optimal pH=2), requiring additional acidification treatment. Furthermore, this method has high requirements for parameter control; the monomer concentration, oxidant concentration, and dropping rate must be strictly controlled during the preparation process, and strict requirements are placed on stirring time and reaction time, which is not conducive to large-scale industrial production.

[0009] Macroporous ion exchange resins, as classic carriers, are functional polymers with permanent channels and a high molecular framework structure. They are insoluble and infusible, achieving separation, purification, and catalysis through the reversible exchange of mobile ions on their functional groups with like ions in solution. Compared to traditional gel resins, they not only possess traditional ion exchange properties but also exhibit excellent physical adsorption performance. Therefore, they are widely used in water treatment, food processing, biomedicine, environmental protection, and chemical synthesis, and are particularly suitable for treating complex systems containing macromolecules or organic matter.

[0010] Existing technologies disclose processes for combining UiO-66 with macroporous resins. However, during the preparation process, the composite effect of UiO-66 and macroporous resins is unsatisfactory. UiO-66 easily forms large crystals on the surface of the macroporous resin, resulting in agglomeration. Furthermore, the nucleation rate and crystal size during the in-situ growth of UiO-66 are difficult to control, and the resulting large crystals may block the resin pores. These combined factors lead to a decrease in the specific surface area and pore utilization rate of the composite material, thus affecting its adsorption performance for pollutants. Simultaneously, in the UiO-66 and macroporous resin composite materials prepared by existing processes, the UiO-66 crystals do not adhere firmly to the macroporous resin and are prone to detachment during the recycling process of adsorbed pollutants, resulting in poor long-term cycling stability.

[0011] Furthermore, the inventors also discovered that the UiO-66-macroporous resin composite material prepared by the existing process is only suitable for adsorbing small-sized inorganic anions, and has a large mass transfer resistance to large-molecule antibiotics; and it lacks specific action sites for antibiotic molecules; at the same time, the adsorption capacity and adsorption rate of the UiO-66-macroporous resin composite system for antibiotics need to be further improved. Summary of the Invention

[0012] To address the technical problems existing in the prior art, this invention provides a method for preparing a UiO-66 / macroporous resin composite material. By combining the water-stable UiO-66 metal-organic framework material with a macroporous ion exchange resin, a composite adsorption system with stable structure, abundant pores, and synergistic enhancement of functional sites is constructed. This method effectively overcomes the problems of poor dispersibility of UiO-66, easy formation of large crystal agglomerates, and easy clogging of resin pores in existing UiO-66 and macroporous resin composite processes. It also improves the adhesion of UiO-66 on the macroporous resin, preventing it from falling off during adsorption cycles and improving long-term cycle stability. At the same time, it can also effectively improve the targeted adsorption performance of the composite material for antibiotics, thereby achieving efficient removal of antibiotics and other organic pollutants from water.

[0013] The present invention also provides a UiO-66 / macroporous resin composite material prepared by the aforementioned method, which has high stability, high antibiotic adsorption capacity and good engineering applicability.

[0014] The present invention also provides the application of the UiO-66 / macroporous resin composite material for adsorbing antibiotics in water.

[0015] To solve the above technical problems, the technical solution adopted by the present invention is as follows: A method for preparing a UiO-66 / macroporous resin composite material includes the following steps: Step S01: Dissolve zirconium tetrachloride in N,N-dimethylformamide, then add sorbitol and mix well to obtain a precursor solution; Step S02: The macroporous resin is washed with deionized water, then replaced with ethanol, and then immersed in a precursor solution. After immersion, terephthalic acid and deionized water are added to the precursor solution, mixed evenly, and then placed in a sealed container for hydrothermal reaction. After the hydrothermal reaction is completed, the solid is separated and washed and dried to obtain the UiO-66 / macroporous resin composite material.

[0016] Preferably, in step S01, the concentration of zirconium tetrachloride in the precursor solution is 0.1-0.15 mol / L; The molar ratio of sorbitol to zirconium tetrachloride is 1-3:1.

[0017] Preferably, in step S02, the mass ratio of zirconium tetrachloride to macroporous resin in the precursor solution is controlled to be 1:2-4. The macroporous resin is a macroporous, weakly basic styrene-based anion exchange resin.

[0018] Preferably, in step S02, the molar ratio of zirconium tetrachloride to terephthalic acid in the precursor solution is controlled to be 1:1-2.

[0019] Preferably, in step S02, the molar ratio of zirconium tetrachloride to deionized water in the precursor solution is controlled to be 1:2-5.

[0020] Preferably, in step S02, the macroporous resin is immersed in the precursor solution for 1-2 hours; The hydrothermal reaction temperature is 80-100℃, and the hydrothermal reaction time is 12-24h.

[0021] Furthermore, in step S02, the ethanol replacement method is as follows: after the macroporous resin is washed with deionized water, it is placed in an ethanol aqueous solution with a volume concentration of 45-55% for the first replacement, and then placed in anhydrous ethanol for the second replacement.

[0022] A UiO-66 / macroporous resin composite material was prepared using the aforementioned preparation method.

[0023] An application of the aforementioned UiO-66 / macroporous resin composite material includes the following steps: adding the UiO-66 / macroporous resin composite material to wastewater containing antibiotics, adjusting the pH of the solution to 3-11, stirring and adsorbing at room temperature for 1-4 hours, and then separating and recovering the adsorbed UiO-66 / macroporous resin composite material.

[0024] Preferably, the mass-to-volume ratio of UiO-66 / macroporous resin composite material to antibiotic-containing wastewater is 0.1-1g:1000mL.

[0025] Compared with the prior art, the beneficial effects of the present invention are as follows: (1) In the preparation of the UiO-66 / macroporous resin composite material of the present invention, sorbitol is used as a soft template, water as a regulator, and macroporous resin as a carrier to prepare the UiO-66 / macroporous resin composite material. Due to steric hindrance, nanopowder adsorbent materials have limited adsorption capacity for organic macromolecules in water. The present invention combines the metal sites of UiO-66 with the channel advantages of macroporous resin to achieve multifunctional synergistic adsorption. The macroporous resin used can prevent UiO-66 from agglomerating, improve the utilization rate of active sites, and protect the structure of UiO-66.

[0026] (2) In the preparation of the UiO-66 / macroporous resin composite material of the present invention, by using sorbitol as a soft template and regulator, multiple -OH groups in its molecule can undergo moderate coordination with zirconium ions, slowing down the rate of zirconium clusters connecting with terephthalic acid and avoiding explosive and disordered nucleation of UiO-66 crystals in solution. This is conducive to the formation of smaller and more uniform crystals, rather than large and irregular aggregates. As the reaction is slowed down, the precursor solution has more time to diffuse and infiltrate the entire macroporous network structure of the resin. This allows the crystal nucleation sites to be more uniformly distributed on the inner surface of the resin, rather than just concentrated on the outer surface of the resin particles or in the solution. The final composite material is one in which UiO-66 is uniformly loaded inside and outside the resin, rather than a simple physical mixture of the two.

[0027] (3) In the preparation of the UiO-66 / macroporous resin composite material of the present invention, deionized water is used as a regulator to provide the necessary water molecules for the reaction system, which directly participate in and promote the hydrolysis of zirconium tetrachloride precursor to form stable zirconium oxide clusters. Replacing part of the DMF solvent with water significantly reduces raw material costs and reduces the generation of organic waste liquid, making the synthesis process more green, environmentally friendly, and economical, which is of great significance for large-scale production. Adding an appropriate amount of water helps to obtain UiO-66 crystals with better crystallinity and fewer defects. Introducing a certain amount of water makes the resin pretreatment process more compatible, helps to maintain the resin swelling state, and ensures that the reactants smoothly enter the pores. The addition of water is not only chemically necessary for the formation of the correct UiO-66 structure, but also optimizes the crystallization process by adjusting the solvent environment, while having both economic and environmental advantages.

[0028] (4) The preparation method of the UiO-66 / macroporous resin composite material of the present invention combines the water-stable UiO-66 metal-organic framework material with macroporous ion exchange resin. By introducing sorbitol, the crystal nucleation, growth and interfacial bonding of UiO-66 in macroporous resin are effectively regulated, and a composite adsorption system with stable structure, rich pores and synergistic enhancement of functional sites is constructed. This method can effectively overcome the problems of poor dispersibility of UiO-66, easy formation of large crystal agglomeration and easy blockage of resin pores in the existing UiO-66 and macroporous resin composite process, and improve the adhesion of UiO-66 on macroporous resin, avoid detachment during adsorption cycle, and improve long-term cycle stability.

[0029] (5) The UiO-66 / macroporous resin composite material of the present invention exhibits excellent adsorption performance in the adsorption and separation of macromolecular organic pollutants, and can achieve efficient removal of organic pollutants such as antibiotics in water. Attached Figure Description

[0030] Figure 1 The nitrogen adsorption-desorption isotherm curve of the UiO-66 / macroporous resin composite material in Example 1 is shown.

[0031] Figure 2 The image shows the X-ray diffraction pattern of the UiO-66 / macroporous resin composite material of Example 1.

[0032] Figure 3 Scanning electron microscope (SEM) images of UiO-66 synthesized using a conventional solvothermal method and the UiO-66 / macroporous resin composite material from Example 1; wherein, Figure 3 a is a scanning electron microscope image of UiO-66 synthesized by the conventional solvothermal method, at a magnification of 18000; Figure 3 b is a scanning electron microscope image of the UiO-66 / macroporous resin composite material of Example 1, magnified 30000.

[0033] Figure 4 The thermogravimetric analysis (TGA) of the UiO-66 / macroporous resin composite material obtained in Example 1 is shown. Detailed Implementation

[0034] To provide a clearer understanding of the technical features, objectives, and effects of this invention, specific embodiments are now described. It should be noted that the following detailed descriptions are exemplary and intended to provide further explanation of the invention. Unless otherwise specified, all technical and scientific terms used in this invention have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains.

[0035] It should be noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the exemplary embodiments of the present invention. As used herein, "first," "second," etc., are used to distinguish similar objects and are not used to describe a particular order or sequence. Furthermore, it should be understood that when the terms "comprising" and / or "including" are used in this specification, they indicate the presence of features, steps, operations, devices, components, and / or combinations thereof.

[0036] This invention provides a method for preparing a UiO-66 / macroporous resin composite material, comprising the following steps: Step S01: Dissolve zirconium tetrachloride in N,N-dimethylformamide, then add sorbitol and mix well to obtain a precursor solution; Step S02: The macroporous resin is washed with deionized water, then replaced with ethanol, and then immersed in a precursor solution. After immersion, terephthalic acid and deionized water are added to the precursor solution, mixed evenly, and then placed in a sealed container for hydrothermal reaction. After the hydrothermal reaction is completed, the solid is separated and washed and dried to obtain UiO-66(Zr) / macroporous resin composite material.

[0037] In the preparation of the UiO-66 / macroporous resin composite material of the present invention, sorbitol is used as a soft template, water as a regulator, and macroporous resin as a carrier to prepare the UiO-66 / macroporous resin composite material. By using sorbitol as a soft template and regulator, multiple -OH groups in its molecule can undergo moderate coordination with zirconium ions, slowing down the rate of zirconium clusters connecting with terephthalic acid, effectively regulating the formation rate and crystal size of UiO-66 crystal nuclei, and avoiding explosive and disordered nucleation of UiO-66 crystals in solution. This promotes the formation of smaller, more uniform crystals, rather than large and irregular aggregates. Simultaneously, because the reaction is slowed down, the precursor solution has more time to diffuse and infiltrate the entire macroporous network structure of the resin. This allows crystal nucleation sites to be more evenly distributed on the inner surface of the resin, rather than being concentrated only on the outer surface of the resin particles or in the solution; furthermore, sorbitol can coordinate with zirconium ions to form ligand bridges, enhancing the interfacial bonding force between UiO-66 crystals and the resin matrix, improving the composite effect of UiO-66 with macroporous resin and the stability of the composite material.

[0038] Furthermore, in the preparation of the UiO-66 / macroporous resin composite material, deionized water was used as a regulator to provide the necessary water molecules to the reaction system, directly participating in and promoting the hydrolysis of the zirconium tetrachloride precursor to form stable zirconium-oxygen clusters. Adding an appropriate amount of water helps to obtain UiO-66 crystals with better crystallinity and fewer defects. Introducing a certain amount of water makes the resin wetting process more compatible, helps maintain the resin's swollen state, and ensures that the reactants smoothly enter the pores. The addition of water is not only chemically necessary for the formation of the correct UiO-66 structure, but also optimizes the crystallization process by adjusting the solvent environment, while also offering economic and environmental advantages.

[0039] Furthermore, addressing the adsorption defects of UiO-66-macroporous resin composites prepared by existing processes in antibiotics in water, firstly, the polyhydroxy structure of sorbitol improves the hydrophilicity of the material surface and introduces or enhances the hydrogen bonding environment. Simultaneously, by regulating UiO-66 defects and Zr active site exposure, it is beneficial to enhance the interaction between the material and the carboxyl and amide functional groups in meropenem sodium, thereby improving the adsorption specificity for antibiotic pollutants. Secondly, by introducing sorbitol, the crystal nucleation, growth, and interfacial bonding of UiO-66 in the macroporous resin are effectively regulated, improving the uniformity of UiO-66 loading and the utilization rate of effective active sites, thus enhancing the adsorption performance of the composite material for antibiotics such as meropenem sodium.

[0040] Preferably, in step S01, the concentration of zirconium tetrachloride in the precursor solution is 0.1-0.15 mol / L.

[0041] Preferably, in step S01, the molar ratio of sorbitol to zirconium tetrachloride is 1-3:1.

[0042] Preferably, in step S02, the mass ratio of zirconium tetrachloride to macroporous resin in the precursor solution is controlled to be 1:2-4.

[0043] Preferably, in step S02, the macroporous resin is a macroporous weakly basic styrene-based anion exchange resin; more preferably, the macroporous resin is macroporous weakly basic styrene-based anion exchange resin D301.

[0044] Preferably, in step S02, the macroporous resin is immersed in the precursor solution for 1-2 hours.

[0045] Preferably, in step S02, the molar ratio of zirconium tetrachloride to terephthalic acid in the precursor solution is controlled to be 1:1-2.

[0046] Preferably, in step S02, the molar ratio of zirconium tetrachloride to deionized water in the precursor solution is controlled to be 1:2-5. Preferably, in step S02, the temperature of the hydrothermal reaction is 80-100℃, and the time of the hydrothermal reaction is 12-24h.

[0047] Furthermore, the ethanol replacement method involves washing the macroporous resin with deionized water, placing it in an aqueous ethanol solution with a volume concentration of 45-55% for the first replacement, and then placing it in anhydrous ethanol for the second replacement.

[0048] Preferably, in the ethanol replacement process, the first replacement takes 1-1.5 hours, and the second replacement takes 4-5 hours.

[0049] Furthermore, the solids were washed sequentially with deionized water and anhydrous ethanol; the drying temperature was 60-80℃ and the drying time was 12h.

[0050] The present invention also provides a UiO-66 / macroporous resin composite material prepared by the aforementioned method.

[0051] This invention also provides the application of the UiO-66 / macroporous resin composite material, including the following steps: The UiO-66 / macroporous resin composite material was added to the antibiotic-containing wastewater. The pH of the solution was adjusted to 3-11 using a pH adjusting solution. After adsorption by stirring at room temperature for 1-4 hours, the adsorbed UiO-66 / macroporous resin composite material was separated and recovered. The absorbance of the centrifuged supernatant was measured using a UV spectrophotometer, and the concentration of antibiotics in the wastewater after adsorption was calculated.

[0052] Preferably, the mass-to-volume ratio of UiO-66 / macroporous resin composite material to antibiotic-containing wastewater is 0.1-1g:1000mL.

[0053] Preferably, the antibiotic in the antibiotic-containing wastewater is meropenem sodium; the pH adjusting solution is nitric acid or sodium hydroxide solution.

[0054] To enable those skilled in the art to better understand the technical solution of the present invention, the present invention will be further described below in conjunction with some specific embodiments.

[0055] Example 1 This embodiment provides a method for preparing UiO-66 / macroporous resin composite material, the specific steps of which are as follows: (1) Dissolve 10 mmol zirconium tetrachloride and 10 mmol sorbitol in 100 mL DMF, mix thoroughly by sonication to obtain a precursor solution; (2) After washing 4.66g of D301 macroporous resin with deionized water, it was replaced in 50% and 100% ethanol solutions for 1h and 4h respectively, and then added to the aforementioned precursor solution for 1h. Then, 10mmol of terephthalic acid and 360μL of deionized water were added to the precursor solution and stirred evenly. The mixture was then transferred to a high-pressure reactor, sealed, and subjected to hydrothermal reaction at 80℃ for 12h. The solid was collected by centrifugation. The solid was washed repeatedly with deionized water and anhydrous ethanol and then dried in a vacuum drying oven at 60℃ for 12h to obtain UiO-66 / macroporous resin composite material.

[0056] This embodiment also provides a UiO-66 / macroporous resin composite material prepared by the aforementioned method.

[0057] Example 2 This embodiment provides a method for preparing UiO-66 / macroporous resin composite material, the specific steps of which are as follows: (1) Dissolve 10 mmol zirconium tetrachloride and 20 mmol sorbitol in 100 mL DMF, and mix thoroughly by sonication to obtain a precursor solution. (2) After washing 6.99g of D301 macroporous resin with deionized water, it was replaced in 50% and 100% ethanol solutions for 1h and 4h respectively, and then added to the aforementioned precursor solution for 1.5h. Then, 15mmol of terephthalic acid and 540μL of deionized water were added to the precursor solution and stirred evenly. The mixture was then transferred to a high-pressure reactor, sealed, and subjected to hydrothermal reaction at 80℃ for 18h. The solid was collected by centrifugation. The solid was washed repeatedly with deionized water and anhydrous ethanol and then dried in a vacuum drying oven at 60℃ for 12h to obtain UiO-66 / macroporous resin composite material.

[0058] This embodiment also provides a UiO-66 / macroporous resin composite material prepared by the aforementioned method.

[0059] Example 3 This embodiment provides a method for preparing UiO-66 / macroporous resin composite material, the specific steps of which are as follows: (1) Dissolve 10 mmol zirconium tetrachloride and 30 mmol sorbitol in 100 mL DMF, and mix thoroughly by sonication to obtain a precursor solution. (2) After washing 9.32g of D301 macroporous resin with deionized water, it was replaced in 50% and 100% ethanol solutions for 1h and 4h respectively, and then added to the aforementioned precursor solution for 2h. Then, 20mmol of terephthalic acid and 900μL of deionized water were added to the precursor solution and stirred evenly. The mixture was then transferred to a high-pressure reactor, sealed, and subjected to hydrothermal reaction at 100℃ for 24h. The solid was collected by centrifugation. The solid was washed repeatedly with deionized water and anhydrous ethanol and then dried in a vacuum drying oven at 60℃ for 12h to obtain UiO-66 / macroporous resin composite material.

[0060] This embodiment also provides a UiO-66 / macroporous resin composite material prepared by the aforementioned method.

[0061] Comparative Example 1 This comparative example uses the technical solution of Example 1. The difference between this example and Example 1 is that sorbitol is not added in step S01, while the other steps and reaction conditions remain unchanged.

[0062] Comparative Example 2 This comparative example adopts the technical solution of Example 1. The difference between this example and Example 1 is that deionized water is not added in step S02, while other steps and reaction conditions remain unchanged.

[0063] Comparative Example 3 This comparative example adopts the technical solution of Example 1. The difference from Example 1 is that in step S02, IRA402OH small-pore resin is used to replace D301 macroporous resin, while other steps and reaction conditions remain unchanged.

[0064] The specific surface area of ​​the UiO-66 / macroporous resin composites in Examples 1-3 and Comparative Examples 1-3 was tested by nitrogen adsorption-desorption, and the specific results are shown in the table below:

[0065]

[0066] Compared with Comparative Example 1, Example 1 showed a decrease in the specific surface area of ​​the composite material in the absence of sorbitol. This is because the lack of sorbitol's temporary coordination and nucleation control of zirconium ions leads to faster and denser nucleation, resulting in an increase in free UiO-66 powder in the solution and a decrease in loading.

[0067] Compared with Comparative Example 2, Example 1 showed a significant decrease in the specific surface area of ​​the UiO-66 / macroporous resin composite material in the absence of deionized water. Water is commonly used as a regulator or participates in metal coordination, hydrolysis, and coordination equilibrium, thereby affecting the possible coordination structures and uncoordinated sites. Removing water alters nucleation and growth kinetics, easily resulting in large particles, aggregates, or non-ideal disordered phases, thus reducing the specific surface area of ​​the material.

[0068] Compared with Comparative Example 3, Example 1 used a small-porous resin, resulting in a decrease in the specific surface area of ​​the UiO-66 / macroporous resin composite material. This is because, compared with macroporous resins, which have high porosity, small-porous resins have a lower specific surface area. When using small-porous resins as a carrier, crystal growth on its surface or inside is restricted, thus reducing the total specific surface area of ​​the composite material to the level of the small-porous resin bulk. The specific surface area is significantly reduced, and the corresponding coordination sites are also reduced, leading to a significant decrease in specific surface area.

[0069] Application Example 1 100 mg of the UiO-66 / macroporous resin composite material from Example 1 was added to 200 mL of meropenem sodium solution (meropenem sodium concentration was 1 mmol / L). After adjusting the pH to 3, the adsorption was carried out for 4 h at room temperature using a shaking bed. Then, the supernatant was collected by centrifugation. The adsorption capacity of the UiO-66 / macroporous resin composite material for meropenem sodium from a single source was calculated to be 148 mg / g.

[0070] Application Example 2 100 mg of the UiO-66 / macroporous resin composite material from Example 1 was added to 200 mL of meropenem sodium solution (meropenem sodium concentration was 1 mmol / L). After adjusting the pH to 5, the adsorption was carried out for 4 h at room temperature using a shaking bed. Then, the supernatant was collected by centrifugation. The adsorption capacity of the UiO-66 / macroporous resin composite material for meropenem sodium from a single source was calculated to be 145 mg / g.

[0071] Application Example 3 100 mg of the UiO-66 / macroporous resin composite material from Example 1 was added to 200 mL of meropenem sodium solution (meropenem sodium concentration was 1 mmol / L). After adjusting the pH to 6, the adsorption was carried out for 4 h at room temperature using a shaking bed. Then, the supernatant was collected by centrifugation. The adsorption capacity of the UiO-66 / macroporous resin composite material for meropenem sodium from a single source was calculated to be 143 mg / g.

[0072] Application Example 4 100 mg of the UiO-66 / macroporous resin composite material from Example 1 was added to 200 mL of meropenem sodium solution (meropenem sodium concentration was 1 mmol / L). After adjusting the pH to 7, the adsorption was carried out for 4 h at room temperature using a shaking bed. Then, the supernatant was collected by centrifugation. The adsorption capacity of the UiO-66 / macroporous resin composite material for meropenem sodium from a single source was calculated to be 140 mg / g.

[0073] Application Example 5 100 mg of the UiO-66 / macroporous resin composite material from Example 1 was added to 200 mL of meropenem sodium solution (meropenem sodium concentration was 1 mmol / L). After adjusting the pH to 9, the adsorption was carried out for 4 h at room temperature using a shaking bed. Then, the supernatant was collected by centrifugation. The adsorption capacity of the UiO-66 / macroporous resin composite material for meropenem sodium from a single source was calculated to be 127 mg / g.

[0074] Application Example 6 100 mg of the UiO-66 / macroporous resin composite material from Example 1 was added to 200 mL of meropenem sodium solution (meropenem sodium concentration was 1 mmol / L). After adjusting the pH to 11, the adsorption was carried out for 4 h at room temperature using a shaking bed. Then, the supernatant was collected by centrifugation. The adsorption capacity of the UiO-66 / macroporous resin composite material for meropenem sodium from a single source was calculated to be 103 mg / g.

[0075] As shown in Application Examples 1-6, the UiO-66 / macroporous resin composite material exhibits strong adsorption capacity for meropenem sodium under acidic conditions; however, the adsorption of meropenem sodium weakens under strongly alkaline conditions. This is because lower pH levels favor the release of higher concentrations of H+. + At this point, UiO-66 in the resin has a positive potential, which is more conducive to the adsorption of mezlocillin sodium anions by the composite material. However, when pH > 7, UiO-66 has a negative potential, which affects the adsorption of mezlocillin sodium anions by the composite material.

[0076] Figure 1The image shows the nitrogen adsorption-desorption isotherm curves of the UiO-66 / macroporous resin composite material in Example 1. According to the IUPAC classification standards, within the relative pressure range, the nitrogen adsorption-desorption isotherm of the UiO-66 / macroporous resin composite material is primarily Type I, exhibiting a hysteresis loop in the high-pressure region. The nitrogen adsorption isotherm of UiO-66 is a typical Type I curve; at extremely low relative pressures (P / P0 < 0.1), nitrogen molecules rapidly fill its micropores, resulting in a sharp increase in adsorption. Subsequently, the curve flattens out, forming a plateau, indicating that the micropores are filled, with almost no further adsorption in the medium-pressure region. When UiO-66 is successfully loaded or grown on macroporous resins, its own microporous properties dominate the low-pressure portion of the isotherm, thus determining the main morphology of the isotherm. In nitrogen adsorption, due to the large pore size, capillary condensation occurs at very high relative pressures (P / P0 > 0.8, typically close to 0.9-1.0). Because these pores are irregularly shaped and interconnected, the adsorption and desorption pathways are inconsistent, resulting in a hysteresis loop. However, since macropores may have a smaller capacity than micropores and a wider pore size distribution, they often appear short and narrow. Furthermore, sorbitol acts as a soft template / porogen during synthesis, forming a certain proportion of mesoporous / secondary pores after elution. In summary, this strongly demonstrates the successful preparation of the UiO-66 / macroporous resin composite material.

[0077] Figure 2 The X-ray diffraction pattern of the UiO-66 / macroporous resin composite material in Example 1 is shown. The UiO-66 crystal structure exhibits distinct characteristic peaks at 2θ≈7.4°(1 1 1), 8.5°(2 0 0), 14.9°(2 2 2), 17.2°(4 0 0), 25.8°(4 4 2), and 31.1°(4 4 0). The X-ray diffraction pattern of the UiO-66 / macroporous resin composite material shows that the characteristic peaks of UiO-66 at 2θ≈7.4°(1 1 1), 8.5°(2 0 0), 25.8°(4 4 2), and 31.1°(4 4 0) are all present and show virtually no shift.

[0078] Figure 3 Image a is a scanning electron microscope image of UiO-6 synthesized by the conventional solvothermal method, showing obvious agglomeration and clumping. Figure 3 b is a scanning electron microscope image of the UiO-66 / macroporous resin composite material obtained in Example 1. It can be observed that UiO-66 is uniformly distributed on the macroporous resin without obvious agglomeration or clumping. Furthermore, a certain gap is maintained between the crystals, which is beneficial for the adsorption of macromolecular organic pollutants.

[0079] Figure 4The thermogravimetric analysis (TGA) diagram of the UiO-66 / macroporous resin composite material in Example 1 is shown. During the test, the temperature was increased from 25°C to 800°C at a controlled rate of 20.00°C / min. UiO-66 crystals typically begin to decompose at 450-500°C, while the D301 macroporous resin has a tolerance temperature of ≤100°C. The TGA results show that the initial decomposition temperature of the UiO-66 / macroporous resin composite material is approximately 50-80°C higher than that of the original resin, exhibiting superior thermal stability and high-temperature resistance. The introduction of UiO-66 significantly improves the thermal stability of the macroporous resin. UiO-66 crystals form a uniform and dense inorganic protective layer on the resin surface, effectively blocking heat conduction and oxygen diffusion, thus delaying the thermal decomposition process of the polymer matrix. The UiO-66 skeleton contains a stable Zr-O-Zr structure, whose high melting point and thermochemical stability provide support and passivation for the resin matrix during the heating process. Meanwhile, UiO-66 can form hydrogen bonds or electrostatic interactions with the hydroxyl and quaternary ammonium groups on the resin surface, restricting the movement of resin molecular chains and further increasing the glass transition temperature of the material.

[0080] Unless otherwise stated, all percentages used in this invention are mass percentages.

[0081] Finally, it should be noted that the above descriptions are merely preferred embodiments of the present invention and are not intended to limit the present invention. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A method for preparing a UiO-66 / macroporous resin composite material, characterized in that, Includes the following steps: Step S01: Dissolve zirconium tetrachloride in N,N-dimethylformamide, then add sorbitol and mix well to obtain a precursor solution; Step S02: After washing the macroporous resin with deionized water, it is placed in an ethanol aqueous solution with a volume concentration of 45-55% for the first displacement, and then placed in anhydrous ethanol for the second displacement; then it is immersed in the precursor solution; after immersion, terephthalic acid and deionized water are added to the precursor solution, mixed evenly, and placed in a sealed container for hydrothermal reaction; after the hydrothermal reaction is completed, the solid is separated and washed and dried to obtain the UiO-66 / macroporous resin composite material. In step S02, the molar ratio of zirconium tetrachloride to deionized water in the precursor solution is controlled to be 1:2-5.

2. The preparation method of the UiO-66 / macroporous resin composite material according to claim 1, characterized in that, In step S01, the concentration of zirconium tetrachloride in the precursor solution is 0.1-0.15 mol / L; The molar ratio of sorbitol to zirconium tetrachloride is 1-3:

1.

3. The method for preparing the UiO-66 / macroporous resin composite material according to claim 1, characterized in that, In step S02, the mass ratio of zirconium tetrachloride to macroporous resin in the precursor solution is controlled to be 1:2-4. The macroporous resin is a macroporous, weakly basic styrene-based anion exchange resin.

4. The preparation method of the UiO-66 / macroporous resin composite material according to claim 1, characterized in that, In step S02, the molar ratio of zirconium tetrachloride to terephthalic acid in the precursor solution is controlled to be 1:1-2.

5. The method for preparing the UiO-66 / macroporous resin composite material according to claim 1, characterized in that, In step S02, the macroporous resin is immersed in the precursor solution for 1-2 hours. The hydrothermal reaction temperature is 80-100℃, and the hydrothermal reaction time is 12-24h.

6. A UiO-66 / macroporous resin composite material, characterized in that, It is prepared by the preparation method according to any one of claims 1-5.

7. An application of the UiO-66 / macroporous resin composite material as described in claim 6, characterized in that, The process includes the following steps: adding the UiO-66 / macroporous resin composite material to wastewater containing antibiotics, adjusting the pH of the solution to 3-11, stirring and adsorbing at room temperature for 1-4 hours, and then separating and recovering the adsorbed UiO-66 / macroporous resin composite material.

8. The application of the UiO-66 / macroporous resin composite material according to claim 7, characterized in that, The mass-to-volume ratio of UiO-66 / macroporous resin composite material to antibiotic-containing wastewater is 0.1-1g:1000mL.

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