CN118162114B - A magnetic hydrogen-bonded organic framework material for adsorbing lead and copper, and its preparation method and application - Google Patents

Abstract

The present invention relates to the field of material technology, and in particular to a magnetic hydrogen-bonded organic framework material for adsorbing lead and copper, and a preparation method and application thereof. The preparation method comprises the following steps: step 1, preparing Fe ₃ O ₄ magnetic microspheres by coprecipitation method; step 2, dispersing the Fe ₃ O ₄ magnetic microspheres prepared in step 1 into anhydrous ethanol to obtain a Fe ₃ O ₄ magnetic microsphere suspension; step 3, on the basis of the Fe ₃ O ₄ magnetic microsphere suspension prepared in step 2, using 1,3,6,8-tetrakis(p-benzoic acid)pyrene as a reaction material, N,N-dimethylformamide solution and methanol as a reaction solvent to prepare a magnetic hydrogen-bonded organic framework material Fe _{3 O 4 @HOF. The magnetic hydrogen-bonded organic framework material Fe 3 O 4 @HOF prepared} by the method of the present invention can realize the adsorption and removal of lead ions and copper ions in a relatively short time, and has high removal efficiency and large adsorption capacity.

Description

A magnetic hydrogen-bonded organic framework material for adsorbing lead and copper and its preparation method and application

Technical Field

The invention relates to the technical field of materials, and in particular to a magnetic hydrogen-bonded organic framework material for adsorbing lead and copper, and a preparation method and application thereof.

Background Art

With the rapid development of modern industry and agriculture, such as the fertilizer industry and the battery industry, heavy metals are directly or indirectly released into the natural environment. The heavy metals in the environment are transmitted and enriched through the food chain and finally accumulate in the human body, thus producing varying degrees of acute or cumulative toxicity, posing a threat to human health.

Lead (Pb) is a heavy metal element that seriously harms human health. The ideal lead content in the human body is zero. When the lead content in the human body reaches a certain level, it will cause serious damage to the body's blood system and nervous system, affecting the functions of red blood cells and the brain, kidneys, and nervous systems, especially the kidneys and immune systems of children, which are irreversible. Copper ions (Cu) are indispensable trace elements for life entities. Excessive intake of Cu (II) is harmful to humans. Many diseases are related to copper ions, including liver damage, Alzheimer's disease, and even cancer.

At present, there are many water treatment technologies, such as chemical precipitation, biological method, ion exchange method, etc. Among the existing technologies, adsorption has the advantages of low cost, wide application range, convenient implementation, high removal efficiency and environmental compatibility, and can be used to adsorb and remove lead and copper in wastewater.

In the existing technology, adsorbents include zeolite, aluminosilicate minerals, clay, activated carbon, etc. These adsorbents cannot specifically adsorb heavy metal lead and copper ions. Compared with the metal organic framework materials (MOF) and covalent organic framework materials (COF) developed in recent years, the preparation conditions of hydrogen bond organic framework materials (HOF) are milder and do not require harsh synthesis conditions such as high temperature and high pressure.

In the prior art, many hydrogen bond organic frameworks have been synthesized, such as HOF-HATN, HOF-NBDA, HOF-14, Ni-pHOF, etc. These materials are widely used in the fields of proton conduction, catalytic pyrolysis, gas separation, etc., but are less used in the adsorption and removal of heavy metals. Most of the known materials reported are only for a single element, and most of them are for copper ions, and have the disadvantages of low adsorption capacity, poor reuse rate, and long synthesis time. Yang et al. used the solvent diffusion method to synthesize materials for the simultaneous adsorption of lead and copper. Since the solvent does not directly contact the reaction, the time required is 14 days, and the material synthesis cycle is too long. Compared with the synthesis of HOF materials by solvent evaporation, the synthesis efficiency is lower. In addition, these adsorbents generally exist in the form of solid powders, and the materials need to be collected again by centrifugal separation. The adsorption and removal process and device are relatively cumbersome, and there may be problems of unclean removal during the removal process, which causes pollution to the environment.

In the prior art, there are few methods for preparing magnetic hydrogen-bonded organic framework materials. Chinese invention patent CN117024768 A discloses a method for preparing a magnetic hydrogen-bonded organic framework material. The preparation process uses a solvent thermal reaction method. The process of synthesizing Fe ₃ O ₄ takes a long time, which also makes the material synthesis take a long time and the material synthesis efficiency is low. Moreover, the patent only discloses that the obtained material has excellent adsorption capacity for tetracycline antibiotic pollutants in water bodies and can be used as an adsorbent for adsorbing and removing antibiotics in water bodies, and does not disclose any application in the adsorption and removal of heavy metals.

Summary of the invention

In view of the above-mentioned deficiencies in the prior art, the object of the present invention is to provide a magnetic hydrogen-bonded organic framework material for adsorbing lead and copper, and a preparation method and application thereof.

In order to achieve the above-mentioned object of the invention, the technical solution adopted by the present invention is:

In a first aspect, a method for preparing a magnetic hydrogen-bonded organic framework material for adsorbing lead and copper is provided, which comprises the following steps:

Step 1, preparing Fe ₃ O ₄ magnetic microspheres by coprecipitation method;

Step 2, dispersing the Fe ₃ O ₄ magnetic microspheres prepared in step 1 into anhydrous ethanol to obtain a Fe ₃ O ₄ magnetic microsphere suspension;

Step 3: Based on the Fe ₃ O ₄ magnetic microsphere suspension prepared in step 2, 1,3,6,8-tetrakis(p-benzoic acid)pyrene is used as the reaction material, and N,N-dimethylformamide solution and methanol are used as the reaction solvent to prepare the magnetic hydrogen bonded organic framework material Fe ₃ O ₄ @HOF.

Furthermore, the method of step 1 is specifically as follows:

FeCl ₃ and FeSO ₄ ·7H ₂ O in a molar ratio of 2:1 were added to pure water, the solution was adjusted to alkaline, heated and magnetically stirred; after the magnetic stirring, the supernatant was separated and removed by an external magnet, and the precipitate was washed with pure water for multiple times to obtain Fe ₃ O ₄ magnetic microspheres.

Furthermore, the method of step 2 is specifically as follows:

The Fe ₃ O ₄ magnetic microspheres prepared in step 1 were placed in anhydrous ethanol, ultrasonicated for 5 min, and magnetically stirred for 30 min to obtain a uniformly dispersed Fe ₃ O ₄ magnetic microsphere suspension.

Furthermore, the method of step 3 is specifically as follows:

The Fe ₃ O ₄ magnetic microsphere suspension was placed in a volumetric flask according to the mass ratio of Fe ₃ O ₄ magnetic microsphere to 1,3,6,8-tetra(p-benzoyl)pyrene of 3:5, and an external magnet was used to remove the anhydrous ethanol;

Disperse 1,3,6,8-tetrakis(p-benzoic acid)pyrene into N,N-dimethylformamide solution at a mass ratio of 1:150, sonicate until completely dissolved, then add the mixed solution into a volumetric flask containing Fe ₃ O ₄ magnetic microspheres, and stir magnetically for 1 min;

After the magnetic stirring was completed, a certain amount of methanol solution was added to the reaction system, magnetically stirred for 5 minutes, and the system was sealed and placed at room temperature for 12 hours to allow it to fully react; the material was soaked in excess acetone for 2 hours, and the supernatant was separated and removed by an external magnet. The material was washed with acetone for 4 to 5 times to prepare the magnetic hydrogen-bonded organic framework material Fe ₃ O ₄ @HOF.

In a second aspect, a magnetic hydrogen-bonded organic framework material Fe ₃ O ₄ @HOF prepared by the above method is provided.

In a third aspect, a Fe ₃ O ₄ @HOF enriched membrane is provided, which is prepared by loading a magnetic hydrogen-bonded organic framework material Fe ₃ O ₄ @HOF on a glass fiber membrane.

Furthermore, a 0.22 μm glass fiber membrane is selected, and the material of the glass fiber membrane is borosilicate glass fiber.

In a fourth aspect, a Fe ₃ O ₄ @HOF solid phase extraction column is provided, which is prepared by enriching a magnetic hydrogen-bonded organic framework material Fe ₃ O ₄ @HOF on a SPE sieve plate.

The beneficial effects of the present invention are:

(1) The magnetic HOF material of the present invention has a simple synthesis process and requires a short time. It can be synthesized within one day and has a high synthesis efficiency.

(2) The magnetic HOF material of the present invention has the ability to specifically adsorb lead ions and copper ions at the same time. Compared with most materials, it has a large adsorption capacity for lead ions and copper ions. The theoretical adsorption capacity can reach 579.81 mg/g and 146.48 mg/g, and can reach adsorption equilibrium within 15 minutes.

(3) The saturation magnetization value of the magnetic HOF material of the present invention is 25.34, and it has an excellent ability to be isolated by an external magnet and is easy to recycle and reuse; no stirring or centrifugal separation is required during the enrichment process, and no secondary pollution will be caused.

(4) The magnetic HOF material of the present invention has a high reuse rate and good regeneration performance. It can be eluted with 1% hydrochloric acid as an eluent. After 10 consecutive adsorption-desorption cycles, for a 1 mg/L aqueous solution containing both lead and copper, the lead removal rate remains above 98%, and the copper removal rate remains above 95%, showing excellent removal capabilities.

(5) The Fe ₃ O ₄ @HOF enrichment membrane of the present invention can treat wastewater containing lead and copper in a short time, and the lead and copper contents on the membrane can be quantitatively detected by XRF, with a good linear relationship, and the correlation coefficient of XRF is >0.999.

(6) The Fe ₃ O ₄ @HOF solid phase extraction column of the present invention realizes the adsorption of lead and copper by filling the material into the solid phase extraction column. The eluate after elution with hydrochloric acid can be used in conjunction with other detection devices to detect the content of lead and copper in the liquid sample online.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG1 is a SEM image of the magnetic hydrogen-bonded organic framework material Fe ₃ O ₄ @HOF in Example 1 of the present invention;

FIG2 is an XPS graph of the magnetic hydrogen-bonded organic framework material Fe ₃ O ₄ @HOF in Example 1 of the present invention;

FIG3 is a linear relationship diagram between the solution volume and the lead content on the enriched membrane, using XRF to quantitatively detect the lead content on the Fe ₃ O ₄ @HOF enriched membrane in Example 2 of the present invention;

FIG4 is a linear relationship diagram between the solution volume and the copper content on the Fe ₃ O ₄ @HOF enrichment membrane, using XRF to quantitatively detect the copper content on the Fe 3 O 4 @HOF enrichment membrane in Example 2 of the present invention;

FIG5 is an XPS graph of the magnetic hydrogen-bonded organic framework material Fe ₃ O ₄ @HOF after adsorbing lead in Example 4 of the present invention;

FIG6 is an XPS graph of the magnetic hydrogen-bonded organic framework material Fe ₃ O ₄ @HOF after adsorbing copper in Example 4 of the present invention;

FIG. 7 is a VSM diagram of the magnetic intensity of the Fe ₃ O ₄ @HOF material in Example 6 of the present invention.

DETAILED DESCRIPTION

The specific implementation modes of the present invention are described below so that those skilled in the art can understand the present invention. However, it should be clear that the present invention is not limited to the scope of the specific implementation modes. For those of ordinary skill in the art, as long as various changes are within the spirit and scope of the present invention as defined and determined by the attached claims, these changes are obvious, and all inventions and creations utilizing the concept of the present invention are protected.

Example 1

A method for preparing a magnetic hydrogen-bonded organic framework material for adsorbing lead and copper, specifically comprising the following steps:

Step 1. Weigh 9.8 g of FeCl ₃ and 8.4 g of FeSO ₄ ·7H ₂ O and add them to 200 mL of water. Then add a certain amount of ammonia water to adjust the pH of the solution to 11, mix the solution until it is alkaline, heat it to 60°C and stir it magnetically for 30 minutes. After the magnetic stirring, separate and remove the supernatant with an external magnet, wash the black precipitate with pure water for 4 to 5 times, and dry it in an oven at 75°C to obtain Fe ₃ O ₄ magnetic microspheres.

Step 2: Evenly disperse 100 mg of Fe ₃ O ₄ magnetic microspheres obtained in step 1 in 50 mL of anhydrous ethanol, ultrasonicate for 10 min, and magnetically stir for 30 min to obtain a uniformly dispersed Fe ₃ O ₄ magnetic microsphere suspension.

Step 3, weigh 50 mg of 1,3,6,8-tetrakis(p-benzoic acid)pyrene (H4TBAPy) and add it to 7.5 mL of N,N-dimethylformamide solution, ultrasonicate until completely dissolved to obtain a mixed solution, and use an external magnet to remove anhydrous ethanol; take 15 mL of the magnetic microsphere suspension obtained in step 2 and add it to the mixed solution, and stir it magnetically for 2 min; after the magnetic stirring, add 30 mL of methanol solution to the mixed solution, stir it magnetically for 5 min, and keep the system closed at room temperature of about 25°C for 12 h to allow it to react fully; after the reaction, centrifuge at 7000 r for 5 min to remove the supernatant, add 80 mL of acetone solution to soak the material for 2 h; use an external magnet to remove the supernatant, and wash the material with acetone 4 to 5 times to prepare a magnetic hydrogen bonded organic framework material ( _{Fe3O4 @} HOF).

As can be seen from FIG. 1 , there are a large number of microsphere structures on the surface of the hydrogen-bonded organic framework composite material (Fe ₃ O ₄ @HOF) prepared in this example. It is preliminarily determined that Fe ₃ O ₄ magnetic microspheres are successfully grafted onto the surface of the material.

The X-ray photoelectron spectroscopy (XPS) results in Figure 2 show that a new peak at 710 ev corresponding to Fe 2p appears on Fe ₃ O ₄ @HOF, indicating that magnetic Fe ₃ O ₄ is successfully incorporated into Fe ₃ O ₄ @HOF.

Example 2

Fe ₃ O ₄ @HOF enriched membrane was prepared, and the adsorption effect of lead and copper on Fe ₃ O ₄ @HOF enriched membrane was verified.

The Fe ₃ O ₄ @HOF suspension prepared in Example 1 was loaded on a glass fiber membrane by using a vacuum filtration device to prepare a Fe ₃ O ₄ @HOF enriched membrane;

Preferably, in this embodiment, a 0.22 μm glass fiber membrane is selected to prepare Fe ₃ O ₄ @HOF enrichment membrane, and the material of the glass fiber membrane is borosilicate glass fiber; different sizes of filtration devices can be selected, and glass fiber membranes with diameters of 50 mm and 25 mm are selected, and the effective areas of the loaded materials on the membrane are 12.56 cm ² and 3.14 cm ² respectively;

In the specific implementation, a certain amount of Fe ₃ O ₄ @HOF material was weighed into 30 mL of water and magnetically stirred for 5 min to make the material evenly dispersed in the water; it was loaded onto the glass fiber membrane using a vacuum filtration device to obtain a Fe ₃ O ₄ @HOF enriched membrane. The vacuum pump pressure was 0.08 MPa and the pumping speed was 20 L/min.

Pour the aqueous solution containing lead and copper onto the Fe ₃ O ₄ @HOF enrichment membrane, let it stand for 3 min, then turn on the vacuum pump for filtration. The vacuum pump pressure is selected to be 0.02 MPa to allow the solution to fully contact the membrane, thereby fully adsorbing and removing the lead ions and copper ions in the water.

Sufficient amount of 1000 mg/L lead and copper ion solutions were prepared, divided into 1, 2, 5, 10, and 20 mL by volume; different volumes of lead and copper ion solutions were filtered through the above 6 Fe ₃ O ₄ @HOF enrichment membranes, and then the RAW FP signal values of lead and copper on the Fe ₃ O ₄ @HOF enrichment membrane were detected by XRF to explore the linear relationship between the solution volume and the lead content and copper content on the enrichment membrane. The test results are shown in Figures 3-4. It can be seen from the figure that the correlation coefficient r of lead is 0.9997, and the correlation coefficient r of copper is 0.9994, both greater than 0.999, indicating that the solution volume has an excellent correlation with the lead content and copper content on the enrichment membrane when using XRF detection.

Example 3

Preparation of Fe ₃ O ₄ @HOF solid phase extraction column.

The Fe ₃ O ₄ @HOF material prepared in Example 1 was enriched on the SPE sieve plate by using a solid phase extraction device to prepare a Fe ₃ O ₄ @HOF solid phase extraction column. The Fe ₃ O ₄ @HOF solid phase extraction column of the present invention realizes the adsorption of lead and copper by filling the material into the solid phase extraction column, and the eluate after elution with hydrochloric acid can be used in conjunction with other detection devices to detect the content of lead and copper in the liquid sample online.

Example 4

Verify the adsorption and removal effect of Fe ₃ O ₄ @HOF material on lead and copper.

Pb ²⁺ and Cu ²⁺ solutions with concentration gradients of 1, 10, 30, 50, 100, 200, 400, 600, 800, and 1000 mg/L were prepared, and 10 mg of the Fe ₃ O ₄ @HOF material prepared in Example 1 of the present invention was added thereto respectively. After standing for 4 h, the supernatant was separated by an external magnet, and the concentrations of Pb ²⁺ and Cu ²⁺ in each supernatant were detected by ICP-OES;

50 mg/L solutions containing Pb ²⁺ and Cu ²⁺ were prepared respectively, 10 mg of the Fe ₃ O ₄ @HOF material prepared in Example 1 of the present invention was added thereto respectively, the time gradient was set to 1, 3, 5, 10, 15, 20, 30, 50, 70, 100, 150, 200, 250, 300 min, magnetic stirring was continuously performed, samples were taken at different time periods, and the concentrations of Pb ²⁺ and Cu ²⁺ in the solutions sampled at each time period were detected by ICP-OES;

The test results show that the theoretical calculated adsorption capacity of the Fe ₃ O ₄ @HOF material of the present invention for lead ion and copper ion removal can reach 579.81 mg/g and 146.48 mg/g, and the adsorption process can reach adsorption equilibrium within 15 minutes. It has the advantages of large adsorption capacity and high adsorption efficiency in actual sample detection.

In addition, the X-ray photoelectron spectrometer (XPS) results (Figures 5-6) showed that after the adsorption of lead and copper, new peaks of 138/143 ev and 934 ev corresponding to Pb 4f and Cu 2p appeared in Fe ₃ O ₄ @HOF, respectively, indicating that Pb ²⁺ and Cu ²⁺ were successfully adsorbed on Fe ₃ O ₄ @HOF, achieving the removal of lead and copper in water.

Example 5

Verify the specific effect of Fe ₃ O ₄ @HOF material on the adsorption and removal of lead and copper.

A sufficient amount of 100 mg/L mixed solution containing 13 elements including Na, Mg, K, Ca and 1 mg/L Mn, Ni, Cu, Zn, Co, Al, As, Cd and Pb was prepared, and 10 mg of the Fe ₃ O ₄ @HOF material prepared in Example 1 of the present invention was added thereto. After standing for 4 hours, the supernatant was separated by an external magnet, and the concentration of each element in the supernatant was detected by ICP-OES;

The test results show that the Fe ₃ O ₄ @HOF material of the present invention contains abundant carboxyl functional groups, and Pb ²⁺ and Cu ²⁺ can coordinate with the O atoms of PFC-1, thereby achieving the adsorption of Pb ²⁺ and Cu ²⁺ . In the presence of coexisting ions, the removal rate of lead ions and copper ions by Fe ₃ O ₄ @HOF remains at 95%, proving that the material is almost not interfered by other coexisting ions during the adsorption of Pb ²⁺ and Cu ²⁺ , and has good specificity for the adsorption of Pb ²⁺ and Cu ²⁺ .

Example 6

Verify the magnetic strength of Fe ₃ O ₄ @HOF material.

A solution containing Pb ²⁺ and Cu ²⁺ at a concentration of 1000 mg/L was prepared, and 10 mg of the Fe ₃ O ₄ @HOF material prepared in Example 1 of the present invention was added thereto; the mixed solution was filtered using a filter, and then magnetic analysis was performed using VSM.

The test results in Figure 7 show that the saturation magnetization value of the Fe ₃ O ₄ @HOF material of the present invention is 25.34, and the saturation magnetization value after the magnetic HOF adsorbs lead and copper is 19.15, which has an excellent ability to be separated by an external magnet, and the material can be removed from the aqueous solution by means of an external magnet.

Example 7

Verify the reproducibility of Fe ₃ O ₄ @HOF material.

Using a 1% hydrochloric acid solution as the eluent for elution, after 10 consecutive adsorption-desorption cycles, the material still showed excellent removal efficiency. The Pb ²⁺ removal rate in a 1 mg/L mixed solution of lead and copper remained above 98%, and the Cu ²⁺ removal rate remained above 95%, with good regeneration performance.

In summary, the patented technical solution discloses a magnetic hydrogen-bonded organic framework material Fe ₃ O ₄ @HOF for adsorbing lead and copper, which can be synthesized within one day with high synthesis efficiency; it can specifically adsorb lead ions and copper ions in the presence of other ions; it has excellent ability to be separated by an external magnet, is easy to recycle and separate, and does not require stirring and centrifugal separation during the enrichment process, and will not cause secondary pollution; it can achieve adsorption and removal of lead ions and copper ions within 15 minutes, with high removal efficiency and large adsorption capacity; the material has good regeneration, and after 10 consecutive adsorption-desorption cycles, it still shows excellent removal efficiency. And the lead content and copper content above can be quantitatively detected by XRF, with a good linear relationship, and the correlation coefficient r >0.999.

It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the present invention can be implemented in other specific forms without departing from the spirit or essential features of the present invention. Therefore, the embodiments should be considered exemplary and non-restrictive in all respects, and the scope of the present invention is defined by the appended claims rather than the above description, and it is intended that all changes falling within the meaning and scope of the equivalent elements of the claims be included in the present invention.

In addition, it should be understood that although the present specification is described according to implementation modes, not every implementation mode contains only one independent technical solution. This narrative method of the specification is only for the sake of clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each embodiment can also be appropriately combined to form other implementation modes that can be understood by those skilled in the art.

Claims (8)

1. A method for preparing a magnetic hydrogen-bonded organic framework material for adsorbing lead and copper, characterized in that it comprises the following steps: Step 1, preparing Fe ₃ O ₄ magnetic microspheres by coprecipitation method; Step 2, dispersing the Fe ₃ O ₄ magnetic microspheres prepared in step 1 into anhydrous ethanol to obtain a Fe ₃ O ₄ magnetic microsphere suspension; Step 3: Based on the Fe ₃ O ₄ magnetic microsphere suspension prepared in step 2, 1,3,6,8-tetrakis(p-benzoic acid)pyrene is used as the reaction material, and N,N-dimethylformamide solution and methanol are used as the reaction solvent to prepare the magnetic hydrogen bonded organic framework material Fe ₃ O ₄ @HOF. 2. The preparation method according to claim 1, characterized in that the method of step 1 is specifically: FeCl ₃ and FeSO ₄ ·7H ₂ O in a molar ratio of 2:1 were added to pure water, the solution was adjusted to alkaline, heated and magnetically stirred; after the magnetic stirring, the supernatant was separated and removed by an external magnet, and the precipitate was washed with pure water for multiple times to obtain Fe ₃ O ₄ magnetic microspheres. 3. The preparation method according to claim 1, characterized in that the method of step 2 is specifically: The Fe ₃ O ₄ magnetic microspheres prepared in step 1 were placed in anhydrous ethanol, ultrasonicated for 5 min, and magnetically stirred for 30 min to obtain a uniformly dispersed Fe ₃ O ₄ magnetic microsphere suspension. 4. The preparation method according to claim 1, characterized in that the method of step 3 is specifically: The Fe ₃ O ₄ magnetic microsphere suspension was placed in a volumetric flask according to the mass ratio of Fe ₃ O ₄ magnetic microsphere to 1,3,6,8-tetra(p-benzoyl)pyrene of 3:5, and an external magnet was used to remove the anhydrous ethanol; Disperse 1,3,6,8-tetrakis(p-benzoic acid)pyrene into N,N-dimethylformamide solution at a mass ratio of 1:150, sonicate until completely dissolved, then add the mixed solution into a volumetric flask containing Fe ₃ O ₄ magnetic microspheres, and stir magnetically for 1 min; After the magnetic stirring was completed, a certain amount of methanol solution was added to the reaction system, magnetically stirred for 5 minutes, and the system was sealed and placed at room temperature for 12 hours to allow it to fully react; the material was soaked in excess acetone for 2 hours, and the supernatant was removed by an external magnet. The material was washed with acetone 4 to 5 times to prepare the magnetic hydrogen bond organic framework material Fe ₃ O ₄ @HOF. 5. The magnetic hydrogen-bonded organic framework material _Fe3O4 @ _HOF prepared by the method according to any one of claims 1 to 4. 6 . An Fe ₃ O ₄ @HOF enriched membrane, characterized in that it is prepared by loading the magnetic hydrogen-bonded organic framework material Fe ₃ O ₄ @HOF according to claim 5 on a glass fiber membrane. 7 . The Fe ₃ O ₄ @HOF enrichment membrane according to claim 6 , characterized in that a 0.22 μm glass fiber membrane is selected, and the material of the glass fiber membrane is borosilicate glass fiber. 8. A _{Fe3O4 @} HOF solid phase extraction column, characterized in that it is prepared by enriching the magnetic hydrogen bond organic framework material _{Fe3O4 @} HOF according to claim 5 onto a SPE sieve plate.