N, O site functionalized cofs adsorption material and preparation method and application thereof

Abstract

The application provides an N, O site functionalized COFs adsorption material and a preparation method and application thereof. The N, O site functionalized COFs adsorption material is prepared by reaction of an aldehyde group monomer containing N or O sites and an amino monomer. The N, O site functionalized COFs adsorption material has excellent affinity to thorium ions, so that the N, O site functionalized COFs adsorption material has high thorium adsorption capacity and adsorption selectivity; meanwhile, due to strong chelation coordination interaction between N, O bidentate sites and thorium ions, the material can quickly reach adsorption saturation within 1h. Therefore, the N, O site functionalized COFs adsorption material prepared by the application can be used as an excellent solid adsorption material and applied to selective adsorption and separation of thorium.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of chemistry and environmental technology, in particular to a kind of N, O site functionalized COFs adsorption material and its preparation method and application. BACKGROUND

[0002] Nuclear energy as a kind of efficient and sustainable energy plays a huge role in the world energy structure. And how to actively promote the recycling of spent fuel is the key to guarantee the sustainable development of nuclear energy. Thorium element is recognized as a very promising nuclear fuel. Therefore, in the spent fuel reprocessing process, efficient and high selectivity recovery and separation of thorium is an effective way to achieve full utilization of nuclear fuel.

[0003] In recent years, various technologies such as precipitation, ion exchange, adsorption, membrane filtration and electrochemical methods have been used to separate and enrich radionuclides. Among them, solid adsorption method is widely concerned due to its simple operation, cost-effective and other advantages. So far, several solid adsorbents have been reported for the adsorption and separation of Th(IV) ions, such as porous carbon, zeolite, metal-organic framework materials (MOFs), etc. The literature Journal of Radioanalytical and Nuclear Chemistry, 2016, 310:597-609 reported a high-silicon zeolite NKF-6 as a thorium adsorbent, with a saturated adsorption capacity of only 39 mg / g when the initial concentration was 33 ppm. And due to the fact that the zeolite material is mainly based on ion exchange, it leads to low adsorption selectivity, and also produces a large amount of waste solids. The literature ACS Applied Materials & Interfaces, 2017, 9(41):36026-37 reported a metal-organic framework material (Fe3O4@AMCA-MIL53(Al)) based on magnetite for removing U(VI) and Th(IV) ions from water environment. Due to the poor stability of MOFs material, the structure is easy to collapse under acidic conditions, so that Fe3O4@AMCA-MIL53(Al) hardly adsorbs at pH=1.0-5.0, and at pH=6.0, the adsorption capacity for Th(IV) and U(VI) is only 25 and 23 mg / g, respectively.

[0004] Covalent organic frameworks (COFs) are a new class of porous crystalline polymers connected by covalent bonds. The building units of COFs can be designed and adjusted at the molecular level to optimize the framework structure and surface properties, making them have excellent adsorption capacity. However, although some pioneering COFs have been reported for radionuclide adsorption, porous materials exhibiting high adsorption efficiency for Th(IV) are still very rare in practical applications. This is mainly due to the strong competitive adsorption, which requires the porous material to have unique affinity for thorium ions, and needs to overcome the serious interference of other metal ions. SUMMARY

[0005] In view of this, the present application provides an N, O site functionalized COFs adsorption material and its preparation method and application, to solve the problems of poor stability, poor selectivity and low adsorption capacity of traditional solid adsorbents, and realize efficient adsorption and removal of thorium.

[0006] The technical scheme of the present application is as follows:

[0007] An N, O site functionalized COFs adsorption material, the structure of the COFs is shown as formula I-III, which are named as THz-DFDM COF, TAPT-TPT COF and TAPT-DHTA COF in turn:

[0008]

[0009] The preparation method of the N, O site functionalized COFs adsorption material comprises the following steps: adding aldehyde monomers and amino monomers into a pyrex tube, adding an organic solvent to mix uniformly under ultrasonic, then adding a catalyst, freezing the pyrex tube in liquid nitrogen, vacuumizing and flame sealing the tube, crystallizing by heating, Soxhlet extraction and washing, and drying, to obtain the N, O site functionalized COFs adsorption material.

[0010] Further, the aldehyde monomer is one of 2,5-dimethoxybenzene-1,4-diformaldehyde, 2,4,6-tris(4-formylphenoxy)-1,3,5-triazine and 2,5-dihydroxybenzene-1,4-diformaldehyde; and the amino monomer is one of 1,3,5-benzene triformazan and 2,4,6-tris(4-aminophenyl)-1,3,5-triazine.

[0011] Further, the molar ratio of the aldehyde monomer and the amino monomer is 1-1.5:1.

[0012] Further, the organic solvent is one or more of o-dichlorobenzene, N,N-dimethylacetamide, n-butanol, 1,4-dioxane, mesitylene; the catalyst is an acetic acid aqueous solution, and the concentration of the acetic acid aqueous solution is 1-6 mol / L.

[0013] Further, the ratio of the total mass of the aldehyde monomer and the amino monomer to the volume of the organic solvent is 30-55 mg: 0.5-3.0 mL; and the volume ratio of the catalyst to the organic solvent is 1:2.3-10.

[0014] Further, the temperature of the heating and crystallization reaction is 60-180 DEG C, and the reaction time is 3-7 days.

[0015] Further, the solvent used in the Soxhlet extraction is one or both of methanol and tetrahydrofuran.

[0016] An N,O site functionalized COFs adsorption material is prepared by any one of the preparation methods of the application.

[0017] The application provides an application of the N,O site functionalized COFs adsorption material in adsorbing thorium.

[0018] Further, the application of the N,O site functionalized COFs adsorption material as an adsorbent in adsorbing thorium.

[0019] Further, the N,O site functionalized COFs adsorption material of the application is added into a water body to adsorb and enrich Th(IV), and the pH value of the thorium ion solution is 1.0-5.0.

[0020] Further, the pH value of the thorium ion solution adsorbed by the N,O site functionalized COFs adsorption material is 3.0-5.0.

[0021] Further, the pH value of the thorium ion solution adsorbed by the N,O site functionalized COFs adsorption material is 4.0-5.0.

[0022] Compared with the prior art, the application has the following beneficial effects:

[0023] The application uses an aldehyde monomer and an amino monomer containing N,O functional sites as raw materials to prepare a thorium adsorption material with excellent adsorption performance.

[0024] The N, O site functionalized COF adsorption material prepared in the application has unique affinity for Th(IV), high metal ion selectivity and adsorption capacity, can be applied to complex component containing thorium wastewater, and the product is environmentally friendly. In addition, the N, O site functionalized COF adsorption material in the application still has strong adsorption performance after being used for adsorbing thorium and being regenerated for many times, the adsorption material has stable performance and high reusability. BRIEF DESCRIPTION OF DRAWINGS

[0025] Figure 1 The FT-IR spectra of the N, O site functionalized COF adsorption materials prepared in examples 1, 2 and 3 of the application; wherein (a) is the FT-IR spectrum of the THz-DFDM COF prepared in example 1, (b) is the FT-IR spectrum of the TAPT-TPT COF prepared in example 2, and (c) is the FT-IR spectrum of the TAPT-DHTA COF prepared in example 3.

[0026] Figure 2 The PXRD spectra of the N, O site functionalized COF adsorption materials prepared in examples 1, 2 and 3 of the application; wherein (a) is the PXRD spectrum of the THz-DFDM COF prepared in example 1, (b) is the PXRD spectrum of the TAPT-TPT COF prepared in example 2, and (c) is the PXRD spectrum of the TAPT-DHTA COF prepared in example 3.

[0027] Figure 3 The SEM photos of the N, O site functionalized COF adsorption materials prepared in examples 1, 2 and 3 of the application; wherein (a) is the SEM photo of the THz-DFDM COF prepared in example 1, (b) is the SEM photo of the TAPT-TPT COF prepared in example 2, and (c) is the SEM photo of the TAPT-DHTA COF prepared in example 3.

[0028] Figure 4 The adsorption amount graphs of Th(IV) of the N, O site functionalized COF adsorption materials prepared in examples 1, 2 and 3 of the application under different pH conditions; wherein (a) is the adsorption amount graph of Th(IV) of the THz-DFDM COF prepared in example 1, (b) is the adsorption amount graph of Th(IV) of the TAPT-TPT COF prepared in example 2, and (c) is the adsorption amount graph of Th(IV) of the TAPT-DHTA COF prepared in example 3.

[0029] Figure 5 The adsorption kinetics graph of thorium of the TAPT-DHTA COF prepared in example 3 of the application.

[0030] Figure 6 This is a graph showing the adsorption capacity of TAPT-DHTACOF prepared in Example 3 of the present invention for multi-component competing ions.

[0031] Figure 7 The diagram shows the recycling performance of the TAPT-DHTA COF prepared in Example 3 of this invention. Detailed Implementation

[0032] To better understand the technical content of this invention, specific embodiments are provided below to further illustrate the invention.

[0033] Unless otherwise specified, the experimental methods used in the embodiments of this invention are all conventional methods.

[0034] Unless otherwise specified, all materials and reagents used in the embodiments of this invention are commercially available.

[0035] The Pyrex tube of this invention has a diameter of 26 mm, a length of 125 mm, and a capacity of 10 mL.

[0036] Example 1: Preparation of THz-DFDM COF Material

[0037] 0.075 mmol of 2,5-dimethoxybenzaldehyde-1,4-dicarboxaldehyde and 0.075 mmol of 1,3,5-benzenetricarboxylhydrazine were added to a 10 mL Piezerx tube. 2 mL of a 1:3 mixture of 1,4-dioxane and mesitylene was added as an organic solvent, and the mixture was sonicated for 15 min. 0.2 mL of a 6 mol / L acetic acid aqueous solution was added as a catalyst. The Piezerx tube was then rapidly frozen in liquid nitrogen at 77 K. After degassing through three freeze-pump-thaw cycles, the tube was evacuated and flame-sealed. It was then heated at 120 °C for 3 days. The obtained solid was subjected to Soxhlet extraction with 5 mL of anhydrous tetrahydrofuran for 24 h, followed by vacuum drying at 100 °C for 8 h to obtain a yellow solid powder, named THz-DFDM COF. The yield of this THz-DFDM COF material was 72%, and its BET specific surface area was 187 m². 2 / g, pore volume 0.3cm³ 3 / g. For example... Figure 1 As shown in (a), the information analysis results obtained by FT-IR spectroscopy indicate that after the reaction, the [symbol] is located at 2866 cm⁻¹. -1 and 3388cm -1 The signal peaks at 1545 cm⁻¹, attributed to aldehyde and amino groups respectively, disappeared, while the signal peaks at 1545 cm⁻¹ disappeared. -1 The appearance of a stretching vibration peak corresponding to C=N indicates that the two monomers successfully formed an imine bond through Schiff base polymerization.

[0038] Example 2 Preparation of TAPT-TPT COF material

[0039] 2,4,6-tris(4-formylphenoxy)-1,3,5-triazine (0.05 mmol), 2,4,6-tris(4- aminophenyl)-1,3,5-triazine (0.05 mmol) were added into a 10 mL Pirex tube, 0.5 mL of organic solvent of o-dichlorobenzene and n-butanol mixed in a volume ratio of 1:1 was added and ultrasonic for 15 min, 0.05 mL of 6 mol / L acetic acid aqueous solution was added as catalyst, then the Pirex tube was placed in liquid nitrogen and rapidly frozen at 77 K, degassed by 3 cycles of freeze-pump-thaw, vacuumized and flame-sealed, heated at 60 °C for 1 day, Soxhlet extracted with tetrahydrofuran (5 mL) for 24 h, and dried at 90 °C under vacuum for 12 h to obtain a white powder, named as TAPT-TPT COF. The yield of the TAPT-TPT COF material was 71% and the BET specific surface area was 1802.5 m 2 / g. As shown in Figure 1 (b), the information analysis results obtained by FT-IR spectrum: the sample after reaction appeared an infrared absorption peak at 1614 cm -1 corresponding to C=N bond, indicating the formation of imine linkage.

[0040] Example 3 Preparation of TAPT-DHTA COF material

[0041] 2,5-dihydroxybenzene-1,4-dicarboxaldehyde (0.13 mmol) and 2,4,6-tris(4- aminophenyl)-1,3,5-triazine (0.09 mmol) were added into a 10 mL Pirex tube, 2 mL of organic solvent of o-dichlorobenzene and N,N-dimethylacetamide mixed in a volume ratio of 9:1 was added and ultrasonic for 15 min, 0.2 mL of 6 mol / L acetic acid aqueous solution was added as catalyst, rapidly frozen at 77 K, degassed by 3 cycles of freeze-pump-thaw, vacuumized and flame-sealed, heated at 120 °C for 3 days, the obtained solid was Soxhlet extracted with anhydrous tetrahydrofuran (5 mL) for 24 h, and dried at 120 °C under vacuum overnight to obtain a red solid powder, named as TAPT-DHTA COF. The yield of the TAPT-DHTA COF material was 70% and the BET specific surface area was 787 m 2 / g, and the pore volume was 0.61 cm 3 / g. As shown in Figure 1 (c), the information analysis results obtained by FT-IR spectrum: an infrared absorption peak at 1614 cm -1 corresponding to C=N bond appeared, indicating the successful formation of imine bond.

[0042] In addition, powder XRD tests were performed on the THz-DFDM COF material, the TAPT-TPT COF material and the TAPT-DHTA COF material prepared in Examples 1-3, and the results are shown in Figure 2 As can be seen from the results, all the three materials have obvious characteristic diffraction peaks, indicating that the prepared N,O site functionalized COF adsorbent has high crystallinity. Figure 2 Scanning electron microscope (SEM) tests were performed on the three materials, and the results are shown in Figure 3 As can be seen from the results, the three synthesized materials have regular and ordered morphology, wherein the THz-DFDM COF has a nanorod structure, the TAPT-TPT COF has a nanosphere structure, and the TAPT-DHTA COF has a fiber network structure. Figure 3

[0043] Example 4 Thorium adsorption experiments of N,O site functionalized COF adsorbent at different pH values

[0044] The N,O site functionalized COF adsorbent prepared in Examples 1-3 was used for thorium adsorption experiments at room temperature. The initial concentration of the thorium solution was 100 ppm, and 0.1 mol / L nitric acid and / or 0.1 mol / L sodium hydroxide solution was added to adjust the pH value of the test solution to 1.0, 2.0, 3.0, 4.0 and 5.0, respectively. Then, the N,O site functionalized COF adsorbent prepared in Examples 1-3 was added as an adsorbent to the test solution for adsorption experiments, and the mass ratio of the adsorbent to the test solution was 2 mg:6 mL. The adsorption contact time was 24 h, and after 24 h, the adsorption solution was filtered with a filter membrane. The concentration of thorium ions before and after adsorption was determined by inductively coupled plasma emission spectrometry, and the experimental results are shown in Figure 4

[0045] As can be seen from the results, the adsorption performance of the N,O site functionalized COF adsorbent THz-DFDM COF, TAPT-TPT COF and TAPT-DHTA COF gradually increased at pH 1.0-3.0, and the maximum adsorption capacity was reached at pH 4.0, and the adsorption saturation was reached at this initial concentration. Figure 4

[0046] Example 5 Adsorption isotherm experiments of N,O site functionalized COF adsorbent on thorium

[0047] ​​​From the above experiment of Example 4, the optimal pH value for thorium adsorption is 4.0. Therefore, the maximum saturated adsorption capacity of the three N, O site functionalized COF adsorption materials is tested at pH = 4.0 of the thorium solution. The initial concentration of thorium ions is 25-400 ppm, the adsorption time is 24 h, and after adsorption, the adsorption solution is filtered with a filter membrane, and the concentration of thorium ions before and after adsorption is determined by inductively coupled plasma emission spectrometry. The experimental results are shown in Table 1.

[0048] Table 1 Maximum saturated adsorption capacity of N, O site functionalized COF adsorption materials for thorium at pH = 4.0

[0049]

[0050] From Table 1, it can be seen that the material of Example 3 has a higher saturated adsorption capacity, reaching 1394 mg / g, and the adsorption capacities of Examples 1 and 2 are 1233 and 679 mg / g, respectively.

[0051] Example 6 Adsorption kinetics experiment of TAPT-DHTA COF material

[0052] From the above experiment of Example 5, it can be seen that the TAPT-DHTA COF material prepared in Example 3 has a higher saturated adsorption capacity. Therefore, the TAPT-DHTA COF material prepared in Example 3 is subjected to an adsorption kinetics experiment, the pH of the thorium ion solution is 4.0, the initial concentration is 100 ppm, the adsorption time is 1 min-24 h, and after adsorption, the adsorption solution is filtered with a filter membrane, and the concentration of thorium ions before and after adsorption is determined by inductively coupled plasma emission spectrometry. The experimental results are shown in Table 2. Figure 5

[0053] From Figure 5 it can be seen that the TAPT-DHTA COF material can quickly adsorb within 1 min and reach adsorption saturation within 1 h.

[0054] Example 7 Metal ion co-adsorption experiment of TAPT-DHTA COF material

[0055] From the above experiments of Example 5 and Example 6, it can be seen that the TAPT-DHTA COF material prepared in Example 3 has a higher adsorption capacity and adsorption rate. Therefore, the TAPT-DHTA COF material prepared in Example 3 is subjected to a multi-component metal ion co-adsorption experiment, and thorium (Th 4+ ), uranyl (UO2 2+ ), lanthanum (La 3+ ), praseodymium (Pr 3+ ), samarium (Sm 3+ ), europium (Eu 3+ ), gadolinium (Gd 3+ ), and lutetium (Lu​3+ ), rubidium (Rb + ) Different metal ions coexist in a mixed solution, the concentration of each metal ion is 100 ppm, the volume of the mixed solution is 6 mL, 2 mg of TAPT-DHTA COF material is added to the mixed solution for adsorption for 2 h, and the adsorption effect of the TAPT-DHTA COF material on different metal ions is determined. Figure 6

[0056] As can be seen from Figure 6 , in the environment where a plurality of metal ions coexist, the TAPT-DHTA COF material prepared in Example 3 has strong affinity and high selectivity to Th 4+ , and therefore the thorium adsorption material of the present application has excellent adsorption performance for thorium.

[0057] Example 8 Verification of cyclic regeneration performance of TAPT-DHTA COF material

[0058] The TAPT-DHTA COF material prepared in Example 3 was subjected to cyclic regeneration experiment. Under room temperature condition, the TAPT-DHTA COF material was mixed with Th(IV) solution with a concentration of 100 ppm according to a ratio of 20 mg:60 mL for adsorption, the TAPT-DHTA COF material after adsorption for 24 h was soaked in 0.1 mol / L HNO3 aqueous solution for 24 h (solid-liquid ratio of mg / mL = 1:5), filtered, washed with deionized water until the supernatant was neutral, and vacuum dried to obtain the sample after cyclic regeneration, and the sample was subjected to next round of adsorption. The adsorption effect of the sample on thorium after 5 cycles of cyclic regeneration was determined, and the experimental results are shown in Figure 7

[0059] As can be seen from Figure 7 , the thorium adsorbent of the present application still has strong adsorption performance after 5 cycles of cyclic regeneration, which indicates that the adsorption material of the present application has stable performance and high reusability.

[0060] Comparative Example 1

[0061] This comparative example is compared with Example 3, and the process parameters in the preparation process of the TAPT-DHTA COF material are changed, and the rest is the same as Example 3. The preparation method of the TAPT-DHTA COF material of this comparative example is as follows:

[0062] ​​Into a 10 mL PIR tube, 2,5-dihydroxybenzene-1,4-dicarboxaldehyde (0.05 mmol) and 2,4,6-tris(4-aminophenyl)-1,3,5-triazine (0.09 mmol) were added, 1 mL of organic solvent mixture of o-dichlorobenzene and N,N-dimethylacetamide with a volume ratio of 9:1 was added, and ultrasonic was performed for 15 min, 0.2 mL of 3 mol / L acetic acid aqueous solution was added, rapid freezing was performed at 77 K, and after degassing through 2 cycles of freezing-pumping-thawing, vacuumization was performed under vacuum and the tube was sealed by flame sealing, and heating was performed at 90°C for 3 days, after Soxhlet extraction of the obtained solid with anhydrous tetrahydrofuran (5 mL) for 24 h, vacuum drying was performed at 80°C overnight, and a red solid powder was obtained, which was named as TAPT-DHTA COF-2. The yield of the TAPT-DHTA COF-2 material prepared in this comparative example was 52%. The TAPT-DHTA COF-2 material prepared in this comparative example was used for adsorption of thorium solution with an initial concentration C0 of 400 ppm, and the adsorption capacity after 24 h was 421 mg / g. It can be seen that the yield and the adsorption capacity of the TAPT-DHTA COF-2 material prepared in this comparative example are obviously poorer than those of Example 3.

[0063] Comparative Example 2

[0064] This comparative example is compared with Example 3, and the raw materials of aldehyde-based monomers and amino monomers are changed in the preparation process, and the rest is the same as Example 3. The preparation method of this comparative example is as follows:

[0065] Into a 10 mL PIR tube, 1,3,6,8-tetra(p-tolylphenyl)pyrene (0.13 mmol) and p-phenylenediamine (0.09 mmol) were added, 2 mL of organic solvent mixture of o-dichlorobenzene and N,N-dimethylacetamide with a volume ratio of 9:1 was added, and ultrasonic was performed for 15 min, 0.2 mL of 6 mol / L acetic acid was added, rapid freezing was performed at 77 K, and after degassing through 3 cycles of freezing-pumping-thawing, vacuumization was performed under vacuum and the tube was sealed by flame sealing, and heating was performed at 120°C for 3 days, after Soxhlet extraction of the obtained solid with anhydrous tetrahydrofuran (5 mL) for 24 h, vacuum drying was performed at 120°C overnight, and a solid powder was obtained, which was named as A COF. The yield of the A COF material prepared in this comparative example was 58%, and the A COF material prepared in this comparative example was used for adsorption of thorium solution with an initial concentration C0 of 400 ppm, and the adsorption capacity after 24 h was 387 mg / g. It can be seen that the yield and the adsorption capacity of the A COF material prepared in this comparative example are obviously poorer than those of Example 3.

[0066] In summary, the thorium adsorption material prepared in the application has excellent adsorption performance, thorium selectivity, good material stability and high reusability.

[0067] The above merely provides the preferred embodiment of the present application, and is not used to limit the present application. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. An N, O site functionalized COF adsorbent material, characterized in that, The structure of the COFs adsorbent material is shown in the following formula I-III, which are named as THz-DFDM COF, TAPT-TPT COF and TAPT-DHTA COF in sequence, respectively. ， ， 。 2. The method of making N, O site functionalized COF adsorbent material of claim 1, wherein, The method comprises the following steps: The aldehyde monomer and the amino monomer are added into a pyrex tube, an organic solvent is added and ultrasonically mixed to be uniform, a catalyst is added, the pyrex tube is placed in liquid nitrogen for freezing, vacuumized and flame-sealed, and then heated for crystallization, Soxhlet extraction and washing and drying, so as to obtain the N,O site functionalized COFs adsorbent material; the aldehyde monomer is one of 2,5-dimethoxybenzene-1,4-diformaldehyde, 2,4,6-tris(4-formylphenoxy)-1,3,5-triazine and 2,5-dihydroxybenzene-1,4-diformaldehyde; and the amino monomer is one of 1,3,5-benzene triformazan and 2,4,6-tris(4-aminophenyl)-1,3,5-triazine.

3. The method of claim 2, wherein the N, O site functionalized COF adsorbent material is prepared by the method comprising: The molar ratio of the aldehyde monomer to the amino monomer is 1-1.5:

1.

4. The method of claim 2, wherein the N, O site functionalized COF adsorbent material is prepared by the method comprising: The organic solvent is one or more of o-dichlorobenzene, N,N-dimethylacetamide, n-butanol, 1,4-dioxane and mesitylene; and the catalyst is an acetic acid aqueous solution, and the concentration of the acetic acid aqueous solution is 1-6 mol / L.

5. The method of claim 2, wherein the N, O site functionalized COF adsorbent material is prepared by the method comprising: The ratio of the total mass of the aldehyde monomer and the amino monomer to the volume of the organic solvent is 30-55 mg:0.5-3.0 mL; and the volume ratio of the catalyst to the organic solvent is 1:2.3-10.

6. The method of claim 2, wherein the N, O site functionalized COF adsorbent material is prepared by the method comprising: The temperature of the heating crystallization reaction is 60-180℃, and the reaction time is 3-7 days.

7. The method for preparing N,O site-functionalized COFs adsorbent materials according to claim 2, characterized in that, The solvent used in the Soxhlet extraction is one or both of methanol and tetrahydrofuran.

8. The application of the N,O site functionalized COFs adsorbent material in claim 1 or the N,O site functionalized COFs adsorbent material prepared by the preparation method in any one of claims 2-7 in adsorbing thorium.

9. Use according to claim 8, characterized in that, The pH value of the N,O site functionalized COFs adsorbent material in adsorbing a thorium ion solution is 1.0-5.0.

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