Preparation method and application of adsorption material for antibiotics in sewage

Abstract

The invention provides a preparation method of an adsorption material for antibiotics in sewage. The method comprises the following steps: preparing magnetic porous biochar and an MCS-HA precursor, and preparing a reaction mixed solution from 3, 5-pyrazole dicarboxylic acid monohydrate, sodium hydroxide and AlCl3. 6H2O; finally, the adsorption material for the antibiotics in the sewage is prepared. The invention further provides application. The adsorption material is used for adsorbing antibiotics in sewage. The MOF-303 is attached to the MCS-HA precursor by adopting an in-situ synthesis method to construct a hierarchical pore structure, so that not only is a high specific surface area provided, but also diffusion and adsorption of macromolecular pollutants (such as antibiotics) are promoted. Due to the introduction of humic acid, the material is more stable and still has higher adsorption performance after elution, the recycling performance of the material is realized, resources are saved, the cost is reduced, and environmental pollution is reduced.

Description

Technical Field

[0001] The present invention belongs to the technical field of sewage treatment, and particularly relates to a preparation method and application of an adsorbent material for antibiotics in sewage. Background Art

[0002] In recent years, the problem of antibiotic pollution in water bodies has become increasingly severe. Especially fluoroquinolone antibiotics (such as norfloxacin, ciprofloxacin, etc.) pose a serious threat to the environment and human health due to their high chemical stability, poor degradability and potential ecological toxicity. Traditional water treatment technologies such as activated carbon adsorption, chemical precipitation and biodegradation have limitations such as low adsorption capacity, poor selectivity and high risk of secondary pollution. Although metal-organic frameworks (MOFs) are regarded as ideal adsorbents due to their high specific surface area, adjustable pore size and rich surface chemical sites, their insufficient structural stability, single adsorption sites, lack of selectivity and difficulty in recycling pose great challenges in practical applications. Therefore, people have been seeking more stable MOF synthesis methods with rich adsorption sites, strong selectivity and easy recycling.

[0003] Straw-derived biochar has attracted much attention due to its potential for resource utilization. Through pretreatment by impregnation with potassium ferrate combined with pyrolysis, the magnetic functionalization of biochar and the optimization of pore structure can be achieved simultaneously, providing a stable substrate for the in-situ growth of MOFs. Humic acid (HA), as a natural organic matter, its functional groups such as carboxyl and phenolic hydroxyl groups can not only enhance the hydrogen bond and π-π interaction between the material and pollutants, but also stabilize the metal nodes of MOFs through coordination, thereby improving the corrosion resistance of the overall structure. However, in the existing technology, the composite of MOF-303 and biochar mostly uses the physical mixing method, with weak interfacial binding force, which easily leads to the shedding of MOFs. Moreover, the traditional loading process is difficult to balance the synergistic optimization of pore structure and surface chemical properties, limiting the overall improvement of adsorption performance. Therefore, there is an urgent need to develop a green and efficient multifunctional adsorbent material with high adsorption capacity, excellent selectivity, structural stability and easy recycling to meet the treatment requirements of antibiotic pollution in complex water bodies. Summary of the Invention

[0004] The technical problem to be solved by the present invention is to provide a preparation method and application of an adsorbent material for antibiotics in sewage in view of the above-mentioned deficiencies of the prior art. This method uses an in-situ synthesis method to attach MOF-303 to the MCS-HA precursor to construct a hierarchical pore structure, which not only provides a high specific surface area but also promotes the diffusion and adsorption of macromolecular pollutants (such as antibiotics). Due to the introduction of humic acid, the material becomes more stable and still retains high adsorption performance after elution, realizing the recyclability of the material, which not only saves resources and reduces costs but also reduces environmental pollution.

[0005] To solve the above technical problems, the technical solution adopted by the present invention is: a preparation method of an adsorption material for antibiotics in sewage, and the method is as follows: S1. Mix corn straw powder and potassium ferrate, disperse them in water, impregnate and stir at room temperature for 2 h to 6 h, then dry at a temperature of 60°C to 80°C for 12 h to 24 h to obtain the impregnated material. After pyrolysis at a temperature of 500°C to 800°C in a nitrogen atmosphere for 1 h to 4 h, magnetic porous biochar is obtained, named MCS; S2. Mix humic acid and MCS obtained in S1, disperse them in deionized water, then adjust the pH value of the system to 8.5 with ammonia water, stir at a temperature of 25°C to 30°C for 12 h to 24 h, recover the black solid by magnetic separation means, and dry at a temperature of 60°C to 80°C for 12 h to 24 h to obtain the MCS-HA precursor; S3. Dissolve 3,5-pyrazoledicarboxylic acid monohydrate (H2PZDC·H2O) and sodium hydroxide in deionized water to obtain solution A; dissolve AlCl3·6H2O in deionized water to obtain solution B; under room temperature conditions, while stirring, add solution B dropwise to solution A at a dropping rate of 0.5 mL / min to 2 mL / min, and continue to stir for 2 h to obtain a reaction mixture; S4. Add the MCS-HA precursor obtained in S2 to the reaction mixture obtained in S3, heat and reflux at a temperature of 100°C to 120°C in an oil bath for 2 h to 3 h, naturally cool to room temperature, wash with deionized water until the pH value of the supernatant is 5.5 to 6.5, then centrifuge, discard the supernatant, and vacuum-dry the precipitate to obtain an adsorption material for antibiotics in sewage, named MCS-HA@MOF-303.

[0006] Preferably, in S1, the particle size of the corn straw powder is 250 µm to 375 µm; the mass ratio of the corn straw powder to potassium ferrate is 2.5:1.

[0007] Preferably, in S1, the specific surface area of the magnetic porous biochar is 23.59 m 2 / g to 35.71 m 2 / g, and the average pore diameter is 9.24 nm to 12.46 nm.

[0008] Preferably, in S2, the mass ratio of the humic acid to MCS is (0.025 to 0.1):0.2; the ammonia water in S2 is an ammonia water solution with a mass fraction of 25% to 28%.

[0009] Preferably, the mass ratio of the 3,5-pyrazoledicarboxylic acid monohydrate, sodium hydroxide, and AlCl3·6H2O in S3 is (1.39 - 2.09):(0.96 - 1.44):(5.79 - 8.69); the stirring rate in S3 is 200 rpm.

[0010] Preferably, the dosage ratio of the MCS-HA precursor and the reaction mixture in S4 is (0.4 - 0.6) g:80 mL.

[0011] Preferably, the rotation speed of centrifugation in S4 is 4000 rpm - 8000 rpm, and the centrifugation time is 1 min - 5 min; the temperature of vacuum drying is 60°C - 80°C, and the vacuum drying time is 1 h - 2 h.

[0012] Preferably, the specific surface area of the adsorption material for antibiotics in sewage in S4 is 184.29 m 2 / g - 272.93 m 2 / g, and the average pore diameter is 2.01 nm - 4.13 nm.

[0013] The present invention also provides the application of the adsorption material for antibiotics in sewage prepared by the above preparation method, and the adsorption material is used for adsorbing antibiotics in sewage.

[0014] Preferably, when the adsorption material is used to adsorb norfloxacin in sewage, the unit adsorption capacity is 16.07 mg / g - 25.29 mg / g, and the removal rate is 59.06% - 93.41%.

[0015] The present invention has the following advantages compared with the prior art: 1. The present invention uses straw pyrolysis to prepare magnetic porous biochar (MCS), introduces Fe3O4 magnetic particles through the synergistic action of potassium ferrate oxidation-pyrolysis, and realizes the low-cost magnetic separation function; the ammonia-assisted humic acid (HA) loading strategy enhances the surface functional group density of MCS, provides chemical anchoring sites for the in-situ growth of MOF-303, and forms a stable heterogeneous interface; by regulating the crystal growth direction of MOF-303 through hydrothermal method, a "microporous-mesoporous" hierarchical pore structure is constructed, which synergistically improves the adsorption capacity and mass transfer efficiency of hydrophobic antibiotics. This design not only overcomes the structural defects of traditional MOFs, but also realizes the preparation of green materials through the resource utilization of agricultural waste, providing new ideas for the development of efficient water treatment technologies. 2. The present invention has the characteristics that the modification or activation method is relatively simple and easy to regenerate. First, the straw is carbonized and activated, and then a new component, humic acid, is further introduced to improve the adsorption performance of the straw. Using biochar as the substrate makes the growth of MOF-303 more stable. The present invention uses an in-situ synthesis method to attach MOF-303 to the MCS-HA precursor to construct a hierarchical pore structure, which not only provides a high specific surface area but also promotes the diffusion and adsorption of macromolecular pollutants (such as antibiotics). Due to the introduction of humic acid, the material becomes more stable and still retains a high adsorption performance after elution, realizing the recyclability of the material. This not only saves resources and reduces costs but also reduces environmental pollution. Therefore, meeting the requirements of high efficiency, low cost, easy availability, and environmental protection will not only bring good market prospects but also good economic and social benefits.

[0016] The following further describes the present invention in detail with reference to the drawings and embodiments. Description of the Drawings

[0017] Figure 1 Scanning electron micrograph of the magnetic porous biochar prepared in Example 1 of the present invention.

[0018] Figure 2 X-ray diffraction pattern of MCS-HA@MOF-303 prepared in Example 1 of the present invention.

[0019] Figure 3 Pore size distribution diagram of MCS-HA@MOF-303 prepared in Example 1 of the present invention.

[0020] Figure 4 Scanning electron micrographs of MCS-HA and MCS-HA@MOF-303 prepared in Example 1 of the present invention.

[0021] Figure 5 Comparison diagram of the adsorption effects of MCS-HA and MCS-HA@MOF-303 prepared in Example 1 of the present invention on pollutants.

[0022] Figure 6 Removal performance diagram of different antibiotics by MCS-HA@MOF-303 prepared in Example 1 of the present invention for antibiotics in sewage. Detailed Embodiments

[0023] Example 1 The preparation method of the adsorption material for antibiotics in sewage in this example is as follows: S1. Mix 6.25 g of corn straw powder with a particle size of 250 µm to 375 µm and 2.5 g of potassium ferrate, disperse them in 200 mL of water, impregnate and stir at room temperature for 4 h, then dry at 80 °C for 12 h to obtain the impregnated material. After pyrolysis in a tube furnace at 700 °C under a nitrogen atmosphere for 2 h, magnetic porous biochar with a specific surface area of 35.71 m 2 / g and an average pore diameter of 9.24 nm is obtained, named MCS; In this step, magnetic porous biochar (MCS) is prepared by pyrolyzing straw. Fe3O4 magnetic particles are introduced through the synergistic action of potassium ferrate oxidation and pyrolysis, as Figure 1 shown. Specifically, potassium ferrate releases strongly oxidizing Fe 6+ in the solution, attacking the C-O / C-C bonds of cellulose and lignin in the straw, promoting biomass depolymerization and forming a porous structure. The formed Fe 3+ is adsorbed on the straw surface through ion exchange or electrostatic interaction to form an Fe-O-C complex, providing a precursor for the subsequent pyrolysis to generate Fe3O4. Under high-temperature pyrolysis (500 °C to 800 °C, 700 °C in this example) in an inert atmosphere (N2), the straw is carbonized into porous biochar (MCS), and at the same time, Fe 3+ is reduced by the carbon skeleton to Fe 2+ / Fe 3+ with a mixed valence state, generating Fe3O4 nanoparticles. The function of low-cost magnetic separation is realized in the later stage, so as to remove humic acid molecules, residual solvents, metal ions that have not been combined with the magnetic material surface through chemical bonds or physical adsorption (such as Fe³⁺), other small molecule impurities, and incompletely carbonized biomass debris. After magnetic separation, unloaded HA and impurities can be effectively removed, ensuring the effective exposure of active sites on the material surface. At the same time, there is no need for centrifugation or filtration, reducing equipment dependence and energy consumption, and being suitable for large-scale production. It avoids the destruction of HA functional groups (such as carboxyl groups and phenolic hydroxyl groups) by high temperature or chemical cleaning.

[0024] S2. Mix 0.05 g of humic acid and 0.2 g of MCS obtained in S1, disperse them in 45 mL of deionized water, then adjust the pH value of the system to 8.5 with a 25% ammonia water solution, stir at 25 °C for 24 h, recover the black solid by magnetic separation, and dry at 60 °C for 24 h to obtain the MCS-HA precursor; In this step, ammonia water is used to assist in the loading of humic acid (HA), enhancing the density of surface functional groups of MCS, providing chemical anchor sites for the in-situ growth of metal-organic framework material MOF-303 with aluminum ions as the central ions, and forming a stable heterogeneous interface. Specifically, MOF-303 is grown on the surface of MCS-HA, and the carboxyl group of HA is used to react with Al3+ The coordination effect of the MOF forms a heterogeneous interface, enhancing the bonding strength between the MOF and the substrate. Compared with the physical mixing method, in-situ synthesis can avoid the shedding of MOF particles and improve the stability of the material.

[0025] S3. Dissolve 1.74 g of 3,5-pyrazoledicarboxylic acid monohydrate (HPZDC·H2O) and 1.2 g of sodium hydroxide in 50 mL of deionized water to obtain solution A; dissolve 7.24 g of AlCl3·6H2O in 50 mL of deionized water to obtain solution B; at room temperature, use a 100 mL addition funnel to add solution B dropwise to solution A at a rate of 1 mL / min while stirring at a stirring rate of 200 rpm, and continue stirring for 2 h. During the process, a white precipitate is formed, which then becomes turbid, to finally obtain a reaction mixture solution; S4. Add 0.5 g of the MCS-HA precursor obtained in S2 to 80 mL of the reaction mixture obtained in S3, heat and reflux in an oil bath at 120°C for 2 h, cool naturally to room temperature, wash with deionized water until the pH value of the supernatant is 5.5, then centrifuge at 8000 rpm for 1 min, discard the supernatant, and dry the precipitate in vacuum at 60°C for 2 h to obtain an adsorption material for antibiotics in wastewater, named MCS-HA@MOF-303.

[0026] like Figure 2 X-ray diffraction analysis shows that the diffraction peak positions of the MCS-HA@MOF-303 material prepared in this step are highly consistent with the theoretical XRD pattern simulated using Mercury software based on the MOF-303 single crystal structure data (CCDC No. 2078717) archived by the Cambridge Crystallographic Data Center (CCDC). The Bragg angle deviations of characteristic diffraction peaks (e.g., 2θ≈8.7°, 12.3°, and 17.5°) are all less than 0.2°, and the relative peak intensity ratios differ from the simulated values by less than 15%. These results confirm that the synthesized material has consistent lattice parameters (a=12.03 Å, b=14.94 Å, c=14.07 Å) and space group (P2 / nmm) with the reference crystal structure, indicating that its crystallographic characteristics conform to the topological framework of MOF-303.

[0027] In this embodiment, the introduction of humic acid makes the combination of MOF and the base material more stable, and the high adsorption performance is still maintained after elution.

[0028] In this step, the crystal growth direction of MOF-303 in-situ grown on MCS-HA is regulated by the hydrothermal method. Specifically, at a low temperature (100-120 °C, 120 °C in this example), the growth of thermodynamically stable crystal planes can be promoted by extending the reaction time. At the same time, a "micropore-mesopore" hierarchical pore structure is constructed as Figure 3 shown. The pore size distribution of the material is mainly concentrated in 0.87 - 1.81 nm (micropores) and 4.32 - 21.29 nm (mesopores), and the specific surface area is 272.93 m 2 / g, with an average pore size of 2.01 nm. The specific surface area has increased significantly compared with magnetic porous biochar (35.71 → 272.93 m 2 / g), mainly due to the micropore-dominant effect of MOF-303. MOF-303 is a periodic microporous structure (pore size < 2 nm) formed by self-assembly of organic ligands and metal nodes Al 3+ . These micropores provide a large internal surface area, significantly enhancing the overall specific surface area. The average pore size has decreased significantly (9.24 → 2.01 nm), and the proportion of micropores has increased. This is mainly because the introduction of MOF-303 changes the pore distribution of the material from mainly mesopores (9.24 nm) to mainly micropores (2.01 nm), and the pore size distribution is concentrated towards smaller sizes, synergistically enhancing the adsorption capacity and mass transfer efficiency for hydrophobic antibiotics. It not only overcomes the structural defects of traditional MOFs but also realizes the preparation of green materials through the resource utilization of agricultural waste, providing new ideas for the development of efficient water treatment technologies.

[0029] In this invention, an in-situ synthesis method is used to attach MOF-303 to the MCS-HA precursor. As Figure 4 shown, a hierarchical pore structure is constructed, which not only provides a high specific surface area but also promotes the diffusion and adsorption of macromolecular pollutants (such as antibiotics). After loading MOF-303, the performance is significantly improved compared with MCS-HA, as Figure 5 shown.

[0030] This example also provides the application of the prepared adsorbent material, and the adsorbent material is used for the adsorption of antibiotics in sewage.

[0031] As Figure 6As shown, when the adsorbent material is used to adsorb norfloxacin (NOR), its unit adsorption capacity is 25.29 mg / g and the removal rate reaches 93.41%; when used to adsorb tetracycline (TC), its unit adsorption capacity is 0.6 mg / g and the removal rate reaches 2.14%; when used to adsorb chlortetracycline hydrochloride (CTC), its unit adsorption capacity is 5.76 mg / g and the removal rate reaches 18.9%; when used to adsorb oxytetracycline (OTC), its unit adsorption capacity is 0.24 mg / g and the removal rate reaches 8.56%; when used to adsorb sulfamethoxazole (SMX), its unit adsorption capacity is 0.69 mg / g and the removal rate reaches 2.35%; when used to adsorb ciprofloxacin (CIP), its unit adsorption capacity is 4.27 mg / g and the removal rate reaches 15.17%; when used to adsorb levofloxacin (LEV), its unit adsorption capacity is 0.33 mg / g and the removal rate reaches 1.42%. From the above results, it can be seen that the adsorbent material has specificity for the adsorption of norfloxacin.

[0032] Example 2 The preparation method of the adsorbent material for antibiotics in sewage in this example is as follows: S1. After mixing 6.25 g of corn straw powder with a particle size of 250 µm - 375 µm and 2.5 g of potassium ferrate, disperse them in 200 mL of water, impregnate and stir at room temperature for 6 h, then dry at a temperature of 60 °C for 24 h to obtain the impregnated material. After pyrolysis in a tubular furnace at a temperature of 800 °C under a nitrogen atmosphere for 1 h, magnetic porous biochar with a specific surface area of 23.59 m 2 / g and an average pore diameter of 12.46 nm is obtained, named MCS; S2. Mix 0.1 g of humic acid and 0.2 g of MCS obtained in S1, disperse them in 45 mL of deionized water, then adjust the pH value of the system to 8.5 with 28% ammonia water solution, stir at a temperature of 30 °C for 12 h, recover the black solid by magnetic separation means, and dry at 80 °C for 12 h to obtain the MCS-HA precursor; S3. Dissolve 1.39 g of 3,5-pyrazoledicarboxylic acid monohydrate (H2PZDC·H2O) and 0.96 g of sodium hydroxide in 50 mL of deionized water to obtain solution A; dissolve 5.79 g of AlCl3·6H2O in 50 mL of deionized water to obtain solution B; at room temperature, use a 100 mL feeding funnel to drip solution B into solution A at a dropping rate of 0.5 mL / min while stirring at a stirring rate of 200 rpm, and continue to stir for 2 h. During the process, a white precipitate is formed and the reaction mixture becomes turbid, and finally a reaction mixed solution is obtained; S4. Add the MCS-HA precursor obtained in S2 (0.4 g) to the reaction mixture solution obtained in S3 (80 mL), heat and reflux the mixture for 3 h under the condition of an oil bath at 100 °C. After naturally cooling to room temperature, wash it with deionized water until the pH value of the supernatant is 6.5, then centrifuge it at 4000 rpm for 5 min, discard the supernatant, and vacuum-dry the precipitate at 80 °C for 1 h to obtain an adsorption material for antibiotics in sewage, named MCS-HA@MOF-303, with a specific surface area of 184.29 m 2 / g and an average pore diameter of 2.97 nm.

[0033] This example also provides the application of the prepared adsorption material, and the adsorption material is used for adsorbing antibiotics in sewage.

[0034] When the adsorption material is used to adsorb norfloxacin, its unit adsorption capacity is 16.41 mg / g and the removal rate reaches 59.06%. When used to adsorb a complex water body (a binary system with coexisting sulfamethoxazole and norfloxacin), the unit adsorption capacity of norfloxacin is 23.77 mg / g and the removal rate reaches 87.69%; the unit adsorption capacity of sulfamethoxazole is 0.69 mg / g and the removal rate reaches 22.35%. Through calculation, the selectivity coefficient for norfloxacin in the binary system is 295.68, which is much greater than 1. Therefore, the adsorbent is more inclined to adsorb norfloxacin.

[0035] Example 3 The preparation method of the adsorption material for antibiotics in sewage in this example is as follows: S1. Mix 6.25 g of corn straw powder with a particle size of 250 µm - 375 µm and 2.5 g of potassium ferrate, disperse them in 200 mL of water, impregnate and stir at room temperature for 2 h, then dry at 80 °C for 12 h to obtain the impregnated material. After pyrolysis in a tubular furnace at 500 °C for 4 h under a nitrogen atmosphere, magnetic porous biochar with a specific surface area of 30.27 m 2 / g and an average pore diameter of 14.46 nm is obtained, named MCS; S2. Mix 0.025 g of humic acid with 0.2 g of MCS obtained in S1, disperse it in 45 mL of deionized water, then adjust the pH value of the system to 8.5 with a 25% ammonia water solution, stir at 25 °C for 12 h, recover the black solid by magnetic separation, and dry it at 80 °C for 12 h to obtain the MCS-HA precursor; S3. Dissolve 2.09 g of 3,5-pyrazoledicarboxylic acid monohydrate (H2PZDC·H2O) and 1.44 g of sodium hydroxide in 50 mL of deionized water to obtain solution A; dissolve 8.69 g of AlCl3·6H2O in 50 mL of deionized water to obtain solution B; at room temperature, use a 100 mL addition funnel to stir at a stirring rate of 200 rpm while dropping solution B into solution A at a dropping rate of 2 mL / min, and continue stirring for 2 h. During the process, a white precipitate is formed, and the reaction mixture becomes turbid, and finally a reaction mixed solution is obtained. S4. Add 0.6 g of the MCS-HA precursor obtained in S2 to the reaction mixed solution obtained in 80 mL of S3, heat and reflux for 2 h under the condition of an oil bath at 120 °C, naturally cool to room temperature, wash with deionized water until the pH value of the supernatant is 5.5, then centrifuge for 2 min at a rotation speed of 8000 rpm, discard the supernatant, and vacuum dry the precipitate at 80 °C for 1 h to obtain an adsorption material for antibiotics in sewage, named MCS-HA@MOF-303. Its specific surface area is 200.91 m 2 / g, and the average pore size is 4.13 nm.

[0036] This example also provides the application of the prepared adsorption material, and the adsorption material is used for the adsorption of antibiotics in sewage.

[0037] When the adsorption material is used to adsorb norfloxacin, its unit adsorption capacity is 16.07 mg / g, and the removal rate reaches 60.36%.

[0038] The above is only a preferred embodiment of the present invention and does not limit the present invention in any way. Any simple modification, change and equivalent change made to the above embodiments according to the technical essence of the invention still fall within the protection scope of the technical solution of the present invention.

Claims

1. A preparation method of an adsorption material for antibiotics in sewage, characterized in that, The method is as follows: S1. Mix corn straw powder and potassium ferrate, disperse them in water, impregnate and stir at room temperature for 2 h to 6 h, then dry at a temperature of 60 °C to 80 °C for 12 h to 24 h to obtain the impregnated material. Pyrolyze it at a temperature of 500 °C to 800 °C in a nitrogen atmosphere for 1 h to 4 h to obtain magnetic porous biochar, named MCS. S2. Mix humic acid and the MCS obtained in S1, disperse them in deionized water, then adjust the pH value of the system to 8.5 with ammonia water, stir at a temperature of 25 °C to 30 °C for 12 h to 24 h, recover the black solid by magnetic separation means, and dry at a temperature of 60 °C to 80 °C for 12 h to 24 h to obtain the MCS-HA precursor. S3. Dissolve 3,5-pyrazoledicarboxylic acid monohydrate and sodium hydroxide in deionized water to obtain solution A; dissolve AlCl3·6H2O in deionized water to obtain solution B; under room temperature conditions, while stirring, add solution B dropwise to solution A at a dropping rate of 0.5 mL / min to 2 mL / min, and continue to stir for 2 h to obtain a reaction mixture. S4. Add the MCS-HA precursor obtained in S2 to the reaction mixture obtained in S3, heat and reflux at a temperature of 100 °C to 120 °C in an oil bath for 2 h to 3 h, naturally cool to room temperature, wash with deionized water until the pH value of the supernatant is 5.5 to 6.5, then centrifuge, discard the supernatant, and vacuum-dry the precipitate to obtain an adsorption material for antibiotics in sewage, named MCS-HA@MOF-303.

2. The preparation method of an adsorption material for antibiotics in sewage according to claim 1, characterized in that, In S1, the particle size of the corn straw powder is 250 µm to 375 µm; the mass ratio of the corn straw powder to potassium ferrate is 2.5:

1.

3. The preparation method of an adsorption material for antibiotics in sewage according to claim 1, characterized in that, The specific surface area of the magnetic porous biochar described in S1 is 23.59 m 2 / g to 35.71 m 2 / g, and the average pore diameter is 9.24 nm to 12.46 nm.

4. The preparation method of an adsorption material for antibiotics in sewage according to claim 1, characterized in that, In S2, the mass ratio of the humic acid to MCS is (0.025 to 0.1):0.2; the ammonia water in S2 is an ammonia water solution with a mass fraction of 25% to 28%.

5. The preparation method of an adsorption material for antibiotics in sewage according to claim 1, characterized in that, In S3, the mass ratio of 3,5-pyrazoledicarboxylic acid monohydrate, sodium hydroxide and AlCl3·6H2O is (1.39 to 2.09):(0.96 to 1.44):(5.79 to 8.69); the stirring rate in S3 is 200 rpm.

6. The preparation method of an adsorption material for antibiotics in sewage according to claim 1, wherein In S4, the dosage ratio of the MCS-HA precursor to the reaction mixture is (0.4 to 0.6) g:80 mL.

7. The preparation method of an adsorption material for antibiotics in sewage according to claim 1, characterized in that, In S4, the centrifugation speed is 4000 rpm to 8000 rpm, and the centrifugation time is 1 min to 5 min; the temperature of vacuum drying is 60 °C to 80 °C, and the time of vacuum drying is 1 h to 2 h.

8. The preparation method of an adsorption material for antibiotics in sewage according to claim 1, wherein, The specific surface area of the adsorption material for antibiotics in sewage described in S4 is 184.29 m 2 / g to 272.93 m 2 / g, and the average pore diameter is 2.01 nm to 4.13 nm.

9. Use of an adsorption material for antibiotics in sewage prepared by the preparation method according to any one of claims 1-8, characterized in that, The adsorption material is used for adsorbing antibiotics in sewage.

10. The application according to claim 9, characterized in that, When the adsorption material is used for adsorbing norfloxacin in sewage, the unit adsorption capacity is 16.07 mg / g to 25.29 mg / g, and the removal rate is 59.06% to 93.41%.

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