High-capacity hydrogen bond organic framework mixed matrix membrane based on solvent bridging strategy as well as preparation method and application of high-capacity hydrogen bond organic framework mixed matrix membrane

Abstract

The invention provides a high-capacity hydrogen bond organic framework mixed matrix membrane based on a solvent bridging strategy as well as a preparation method and application of the high-capacity hydrogen bond organic framework mixed matrix membrane based on the solvent bridging strategy. Quaternary ammonium anion exchange membrane AEM is used as a base membrane, a polyaminotriazine hydrogen bond organic framework HOFs is used as a modifier, and asymmetric structure disubstituent halogenated acid is used as a bridging solvent; by utilizing the characteristics that acid radicals of a bridging solvent and quaternary ammonium groups of an AEM-based membrane generate electrostatic interaction, and halogen and amino groups of HOFs generate hydrogen-bond interaction, effective bridging of a quaternary ammonium anion exchange membrane AEM and a polyaminotriazine hydrogen-bond organic framework HOFs is realized, the loading capacity of HOFs on the AEM-based membrane is improved, and the high-loading-capacity HOFs mixed matrix membrane is prepared.

Description

Technical Field

[0001] The present invention relates to the technical field of anion separation membranes, and particularly relates to a high-loading hydrogen-bonded organic framework mixed matrix membrane based on a solvent bridging strategy, a preparation method thereof, and an application thereof. Background Art

[0002] Membrane separation technology has received extensive attention due to its characteristics such as high efficiency, energy conservation, and environmental friendliness, and has broad application prospects in the fields of extraction and recovery of ionic resources, environmental remediation, industrial wastewater treatment, etc. The realization of an efficient membrane separation process largely depends on the careful selection of membrane materials.

[0003] The ion sieving performance of polymer membranes is restricted by their relatively wide channel size distribution and low porosity, and it is difficult to break through the "Trade-off" effect between permeability and selectivity. Porous crystal membranes, such as covalent organic frameworks (COFs), metal organic frameworks (MOFs), hydrogen-bonded organic frameworks (HOFs), etc., although have rich and regular pore structures, have weak mechanical strength and are difficult to prepare large-size defect-free membranes, which limits their popularization and use. Introducing crystal porous materials with uniform pore sizes into the polymer matrix to prepare mixed matrix membranes is an effective way to break the current dilemma of difficult efficient ion sieving.

[0004] Desalination, 2024, 576, 117352 reported a kind of MOFs mixed matrix membrane prepared by a blending method. Due to the poor compatibility between MOFs and the matrix, interfacial gaps appeared in the membrane when the MOFs loading was 7.5%. In addition, due to the low content of MOFs, fewer additional ion transport paths were introduced in the membrane, and the Cl - transport rate was only 0.504 mol m -2 h -1 .

[0005] Chinese Patent CN115869791A discloses a preparation method and application of a mixed matrix membrane based on porous organic cages. The porous organic cage CC3 and the polymer are co-dissolved in a mixed solvent by a co-solvent method to prepare a mixed matrix membrane with good compatibility. The highest loading of CC3 is 30%. However, due to the too slow crystallization rate of CC3 during the solvent evaporation process, the resulting porous structure has a non-uniform size distribution, and the cage-shaped CC3 is in an amorphous state. The Cl - / SO 4 2- separation performance is only up to 10.8 at most.

[0006] Therefore, on the premise of high loading, ensuring the stability of the filler framework structure and the compatibility with the matrix are problems that those skilled in the art urgently need to solve. Summary of the Invention

[0007] In view of the deficiencies in this field, the present invention proposes a high-loading HOFs mixed matrix membrane based on a solvent bridging strategy. By means of the hydrogen bonding and electrostatic interactions between the two asymmetrically structured disubstituents at both ends of the solvent and the HOFs modifier and the AEM matrix membrane respectively, the bridging between the HOFs modifier and the AEM matrix membrane is realized, promoting the uniform distribution of HOFs on the membrane. In addition, HOFs are confined to crystallize in the membrane, forming a small-size flaky morphology structure, further improving the compatibility with the polymer matrix, obtaining a mixed matrix membrane with a high HOFs loading, and endowing it with excellent monovalent / divalent anion sieving performance.

[0008] The present invention provides a high-loading HOFs mixed matrix membrane based on a solvent bridging strategy, using an AEM as the matrix membrane, a polyamino triazine-based hydrogen-bonded organic framework (HOFs) as the modifier, and an asymmetrically structured disubstituted haloacid as the bridging solvent. By utilizing the characteristics of the electrostatic interaction between the acid radical of the bridging solvent and the quaternary ammonium group of the AEM matrix membrane and the hydrogen bonding between the halogen and the amino group of HOFs, the effective bridging between the AEM matrix membrane and HOFs is achieved, the loading of HOFs on the AEM matrix membrane is increased, and a high-loading HOFs mixed matrix membrane is prepared.

[0009] In the present invention, the basic principle of preparing by the solvent bridging strategy is as follows:

[0010] The basic principle of preparing by the solvent bridging strategy is to utilize the electrostatic interaction between the acid radical in the asymmetrically structured disubstituted haloacid molecule and the quaternary ammonium group of the AEM matrix membrane and the hydrogen bonding between the halogen and the amino group of HOFs to realize the bridging between the AEM matrix membrane and HOFs.

[0011] In the present invention, the AEM matrix membrane has the following structural formula:

[0012]

[0013] Among them, R 2 is H or an alkyl group with 1-7 carbon atoms.

[0014] Ar 1 is an aryl group, and the aryl group has the following structure

[0015] 、 、 and one of them.

[0016] In the present invention, the polyamino triazine-based hydrogen-bonded organic framework HOFs modifier has the following structure

[0017] 、 、 and One of the following;

[0018] Wherein, R 3 Is H or an alkyl group with 1-2 carbon atoms.

[0019] Ar 2 Is an aryl group, and the aryl group has the following structure

[0020] , And One of the following;

[0021] DAT 1 And DAT 2 Has the following structural formula:

[0022]

[0023] In the present invention, the halogenated acid-bridged solvent has the following structural characteristics:

[0024] X n —R 1 —AH m

[0025] Where X is one or a combination of two or more of F, Cl, Br, I, and n is 1-3;

[0026] R 1 Is an alkyl group with 1-20 carbon atoms;

[0027] AH is an acidic functional group such as a carboxyl group, a sulfonic acid group or a phosphoric acid group, and m is 1-3.

[0028] The halogenated acid-bridged solvent described above includes but is not limited to trifluoroacetic acid (TFA), trifluoromethanesulfonic acid (TFSA), trifluoropropionic acid, dichloroacetic acid, trichloroacetic acid, etc.

[0029] In the present invention, the preparation method of the HOFs mixed matrix membrane is briefly as follows:

[0030] S1: The AEM base membrane and the halogenated acid are mixed and compounded according to a mass ratio of 1:(1-20), homogenized and then left standing for 1-6 h. After the bonding between the functional groups is completed, it is denoted as solution A;

[0031] S2: The HOFs and the halogenated acid are mixed and compounded according to a mass ratio of 1:(1-20), homogenized and then left standing for 1-6 h. After the bonding between the functional groups is completed, it is denoted as solution B;

[0032] S3: Mix the A solution and the B solution according to the mass ratio A:B = 1:(0.1 - 0.5), let it stand for 1 - 6 h after homogenization treatment, wait for the bridging between functional groups to complete, and obtain a clear and transparent membrane solution. Spread the transparent membrane solution on a glass plate and evaporate the solvent at 20°C - 80°C to obtain a high-loading HOFs mixed matrix membrane based on the solvent bridging strategy.

[0033] The second aspect of the present invention provides a high-loading HOFs mixed matrix membrane based on the solvent bridging strategy obtained according to the above preparation method.

[0034] The third aspect of the present invention provides the application of the high-loading HOFs mixed matrix membrane based on the solvent bridging strategy in anion separation, where the anion is Cl - / SO 4 2- , F - / SO 4 2- , Br - / SO 4 2- , NO 3 - / SO 4 2- one or more of them, and the anion separation adopts the electrodialysis method, and the electrodialysis current density is 0.1 - 20 mA cm -2 , and is preferably 5 mA cm in specific embodiments -2 .

[0035] Compared with the prior art, the beneficial effects of the present invention are:

[0036] (1) The HOFs used in the present invention have regular and ordered ion transport channels, and the pore structure formed by flexible hydrogen bond self-assembly can adaptively adjust the pore size during ion transport, reduce the ion transport energy barrier, and improve the ion transport rate.

[0037] (2) The present invention utilizes the hydrogen bond interaction between the asymmetric structure haloacid and HOFs and the electrostatic interaction between the haloacid and the AEM base membrane to promote the uniform distribution of HOFs on the base membrane, enhance the compatibility between HOFs and the matrix, further increase the loading amount, increase the ion transport path in the membrane, and improve the ion transport rate.

[0038] (3) The present invention utilizes the cation-π interaction between the quaternary ammonium group and the aromatic ring to confine the HOFs structural unit near the quaternary ammonium group for in-situ crystallization, and can prepare HOFs crystals with smaller size and flaky morphology in the membrane, improve the compatibility between the polymer and the filler and the filler loading amount, and enhance the ion sieving effect.

[0039] (4) The preparation method of the present invention is simple. The highest loading of the prepared membrane HOFs can reach 50%. At the same time, it has excellent ion transport rate and sieving effect, breaking the "Trade-off" effect between permeability and selectivity. Description of the Drawings

[0040] Figure 1 It is a schematic diagram of the bridging principle of the solvent bridging strategy;

[0041] Figure 2 It is the digital photo of HOFs (A) dissolved in TFA, QPAB-E (B) dissolved in TFA and their blend (C) in Example 1. It can be seen from the figure that QPAB-E and HOFs are uniformly mixed; 1 1

[0042] H 1 The structural formula of HOFs is as follows:

[0043]

[0044] The structural formula of QPAB-E is as follows:

[0045] .

[0046] Figure 3 It is the infrared spectrogram of HOFs powder (A) and HOFs solution (B) with TFA as the solvent in Example 1. It can be seen from the figure that TFA is partially deprotonated to form carboxylate, and at the same time, the amino group in HOFs is protonated in the solution. 1 1 1

[0047] Figure 4 It is the X-ray diffraction comparison diagram of mixed matrix membranes with different HOFs contents in Comparative Example 1 and Example 3. It can be seen from the figure that HOFs crystallize in the membrane after solvent evaporation. 1 1

[0048] Figure 5 It is the infrared spectrum comparison diagram of mixed matrix membranes with different HOFs contents in Comparative Example 1 and Example 3. It can be seen from the figure that the characteristic diffraction peaks of HOFs and polymers are shown in the mixed matrix membrane, indicating that both HOFs and polymers can stably exist in the mixed matrix membrane. 1 1 1

[0049] Figure 6 It is the 50% HOFs prepared by the solvent bridging strategy in Example 3 1- Scanning electron microscope images of the surface (A) and cross-section (B) of the QPAB-E membrane, and the surface (C) and cross-section (D) of the 50% H 1 + QPAB-E membrane prepared by the traditional blending method. It can be seen from the figure that the membrane prepared by the solvent bridging strategy is dense and defect-free, and H 1 OFs are uniformly distributed in the membrane.

[0050] Figure 7 For the structural morphology of H 1 OF in the membrane, the obtaining method is to wash away the QPAB-E matrix with dimethyl sulfoxide and extract H 1 OFs (A) in the membrane prepared by the solvent bridging strategy and H 1 OFs (B) in the traditional blend membrane. It can be seen from the figure that H 1 OFs are smaller in size and show a flaky morphology after crystallization in the membrane, which helps to increase the loading of H 1 OFs in the membrane. Detailed implementation manners

[0051] To make the present invention easy to understand, the preparation method and application of a high-loading HOFs mixed matrix membrane based on the solvent bridging strategy provided by the present invention will be described in detail below with reference to the accompanying drawings and specific examples. Obviously, the described examples are only a part of the examples of the present invention and should not be construed as limiting the protection scope of the present invention.

[0052] Comparative example 1

[0053] 1. In this comparative example, no hydrogen-bonded organic framework HOFs are added, that is, it is a pure polymer membrane.

[0054] The preparation method of the pure polymer membrane is briefly as follows:

[0055] S1: Dissolve 0.1 g of QPAB-E in 1 mL of TFA solution, mix and homogenize, let stand for 2 h to obtain a clear and transparent membrane solution, and then scrape the membrane solution onto a glass plate and evaporate the solvent at 30 °C to obtain a pure polymer anion separation membrane.

[0056] 2. Apply the QPAB-E separation membrane prepared in this comparative example to the electrodialysis separation of Cl - / SO 4 2- , F - / SO 4 2- , Br - / SO 4 2- and NO 3 - / SO 4 2- .

[0057] Place the QPAB-E anion separation membrane prepared in this comparative example in the middle of the concentration chamber and the desalination chamber of the electrodialysis device. The outermost two compartments are 0.3 M Na 2 SO 4 as the buffer solution. The middle two compartments are the desalination chamber and the concentration chamber respectively. Among them, the desalination chamber is 0.1 M NaCl / Na 2 SO 4 , NaF / Na 2 SO 4 , NaBr / Na 2 SO 4 and NaNO 3 / Na 2 SO 4 mixed solution. The concentration chamber is 0.01 M NaNO 3 solution with a volume of 200 mL. The commercial cation exchange membrane used is the CMX membrane produced by ASTOM of Japan. The test time is 1 h. The anion concentration in the concentration chamber is detected by an ion chromatograph of model IC 6000. The anion transport rate and selectivity are calculated according to the concentration.

[0058] The test results show that the Cl - transport rate of the QPAB-E membrane is 3.4 mol m -2 h -1 , corresponding to the Cl - / SO 4 2- selectivity of 8.7; the F - transport rate is 2.9 mol m -2 h -1 , corresponding to the F - / SO 4 2- selectivity of 7.1; the Br - transport rate is 3.7 mol m -2 h -1 , corresponding to the Br - / SO 4 2- selectivity of 13.2; the NO 3 - transport rate is 3.6 mol m -2 h -1 , corresponding to the NO 3 - / SO 4 2- selectivity of 10.3.

[0059] Comparative Example 2

[0060] 1. In this comparative example, no hydrogen-bonded organic framework (HOF) is added, i.e., it is a pure polymer membrane.

[0061] The preparation method of the pure polymer membrane is briefly as follows:

[0062] S1: Dissolve 0.1 g of QPAB-H in 1 mL of TFA solution, mix and homogenize, let it stand for 2 h to obtain a clear and transparent membrane solution. Then scrape the membrane solution onto a glass plate and evaporate the solvent at 30 °C to obtain a pure polymer anion separation membrane. The structural formula of QPAB-H is as follows:

[0063]

[0064] 2. Apply the QPAB-H separation membrane prepared in this comparative example to the electrodialysis separation of Cl - / SO 4 2- , F - / SO 4 2- , Br - / SO 4 2- and NO 3 - / SO 4 2- .

[0065] The electrodialysis method is the same as that in Comparative Example 1.

[0066] The test results show that the Cl - transport rate of the QPAB-H membrane is 3.7 mol m -2 h -1 , corresponding to a Cl - / SO 4 2- selectivity of 6.5; the F - transport rate is 3.1 mol m -2 h -1 , corresponding to an F - / SO 4 2- selectivity of 5.3; the Br - transport rate is 3.9 mol m -2 h -1 , corresponding to a Br - / SO 4 2- selectivity of 10.2; the NO 3 - transport rate is 3.8 mol m -2 h -1 , corresponding to a NO 3 - / SO 4 2- The selectivity is 8.6.

[0067] Example 1

[0068] 1. A method for preparing a high-loading HOFs mixed matrix membrane based on a solvent bridging strategy, the brief steps are as follows:

[0069] S1: Dissolve 0.1 g of QPAB-E in 1 g of TFA solution for mixing and homogenization, let it stand for 2 h, wait for the bonding between functional groups to be completed, and record it as solution A;

[0070] S2: Dissolve 0.1 g of H 1 OFs in 1 g of TFA solution for mixing and homogenization, let it stand for 2 h, wait for the bonding between functional groups to be completed, and record it as solution B;

[0071] S3: Mix solution A and solution B according to the mass ratio A:B = 1:0.1, let it stand for 2 h, wait for the bridging between functional groups to be completed, obtain a clear and transparent membrane solution, and finally scrape the membrane solution onto a glass plate and evaporate the solvent at 30 °C to obtain a high-loading HOFs mixed matrix membrane based on the solvent bridging strategy, recorded as 10% H 1 -QPAB-E.

[0072] 2. Apply the 10% H 1 -QPAB-E anion separation membrane prepared in this example to the electro-dialysis separation of Cl - / SO 4 2- .

[0073] The electro-dialysis method is the same as that in Comparative Example 1.

[0074] The test results show that the Cl 1 transport rate of the 10% H - -QPAB-E anion separation membrane is 3.3 mol m -2 h -1 , corresponding to the Cl - / SO 4 2- selectivity of 26.5. Compared with the pure polymer membrane in Comparative Example 1, the 10% H 1 -QPAB-E anion separation membrane prepared in this example has a Cl - / SO 4 2- selectivity increased by about 3.0 times. In summary, the anion separation membrane prepared in this example has achieved a significant improvement in ion separation efficiency.

[0075] Example 2

[0076] 1. This example adjusts the H 1 OFs content according to the same method as in Example 1 to prepare a 30% H 1 -QPAB-E anion separation membrane.

[0077] 2. Apply the 30% H 1 -QPAB-E anion separation membrane prepared in this example to the electrodialysis separation of Cl - / SO 4 2- in the mixed solution.

[0078] The electrodialysis method is the same as that in Comparative Example 1.

[0079] The test results show that the Cl 1 transport rate of the 30% H - -QPAB-E anion separation membrane is 3.2 mol m -2 h -1 , corresponding to a Cl - / SO 4 2- selectivity of 60.4. Compared with the pure polymer membrane in Comparative Example 1, the 30% H 1 -QPAB-E anion separation membrane prepared in this example has a Cl - / SO 4 2- selectivity increased by about 6.9 times. In summary, the anion separation membrane prepared in this example has achieved a significant improvement in ion separation efficiency.

[0080] Example 3

[0081] 1. This example adjusts the H 1 OFs content according to the same method as in Example 1 to prepare a 50% H 1 -QPAB-E anion separation membrane.

[0082] 2. Apply the 50% H 1 -QPAB-E anion separation membrane prepared in this example to the electrodialysis separation of Cl - / SO 4 2- in the mixed solution.

[0083] The electrodialysis method is the same as that in Comparative Example 1.

[0084] The test results show that the Cl 1 transport rate of the 50% H - -QPAB-E anion separation membrane is 3.0 mol m -2 h -1 , corresponding to a Cl - / SO 42- The selectivity is 86.8. Compared with the pure polymer membrane of Comparative Example 1, the 50% H 1 -QPAB-E anion separation membrane prepared in this example for Cl - / SO 4 2- The selectivity is increased by about 10.0 times. In summary, the anion separation membrane prepared in this example realizes a significant improvement in ion separation efficiency.

[0085] Example 4

[0086] 1. In this example, according to the same method as in Example 3, the quaternary ammonium AEM matrix membrane was changed to QPAB-H to prepare a mixed matrix membrane, denoted as 50% H 1 -QPAB-H.

[0087] 2. Apply the 50% H 1 -QPAB-H anion separation membrane prepared in this example to the electrodialysis separation of Cl - / SO 4 2- .

[0088] The electrodialysis method is the same as that in Comparative Example 1.

[0089] The test results show that the Cl 1 transport rate of the 50% H - -QPAB-H anion separation membrane is 3.2 mol m -2 h -1 , corresponding to a Cl - / SO 4 2- selectivity of 63.5. Compared with the pure polymer membrane of Comparative Example 2, the 50% H 1 -QPAB-H anion separation membrane prepared in this example for Cl - / SO 4 2- The selectivity is increased by about 7.3 times. In summary, the anion separation membrane prepared in this example realizes a significant improvement in ion separation efficiency.

[0090] Example 5

[0091] 1. In this example, according to the same method as in Example 3, the HOFs modifier was changed to H 2 OFs to prepare an anion separation membrane, denoted as 50% H 2 -QPAB-E:

[0092]

[0093] 2. Apply the 50% H 2-QPAB-E anion separation membrane is applied to the electro-dialysis separation of Cl in the mixed solution - / SO 4 2- 。

[0094] The electro-dialysis method is the same as that in Comparative Example 1

[0095] The test results show that the Cl transport rate of the 50% H 2 -QPAB-E anion separation membrane is 3.7 mol m - h -2 h -1 , corresponding to the selectivity of Cl - / SO 4 2- is 64.9. Compared with the pure polymer membrane in Comparative Example 1, the 50% H 2 -QPAB-E anion separation membrane prepared in this example has a selectivity for Cl - / SO 4 2- which is increased by about 7.5 times. In summary, the anion separation membrane prepared in this example realizes a significant improvement in ion separation efficiency

[0096] Example 6

[0097] 1. In this example, according to the same method as in Example 3, the halogenated acid bridging solvent is changed to TFSA to prepare a 50% H 1 -QPAB-E anion separation membrane

[0098] 2. The 50% H 1 -QPAB-E anion separation membrane prepared in this example is applied to the electro-dialysis separation of Cl in the mixed solution - / SO 4 2- 。

[0099] The electro-dialysis method is the same as that in Comparative Example 1

[0100] The test results show that the Cl transport rate of the 50% H 1 -QPAB-E anion separation membrane is 3.1 mol m - h -2 h -1 , corresponding to the selectivity of Cl - / SO 4 2- is 84.5. Compared with the pure polymer membrane in Comparative Example 1, the 50% H 1 -QPAB-E anion separation membrane prepared in this example has a selectivity for Cl - / SO 4 2-The selectivity was increased by about 9.7 times. In summary, the anion separation membrane prepared in this example achieved a significant improvement in ion separation efficiency.

[0101] Example 7

[0102] 1. According to the same method as in Example 3, prepare a 50% H 1 -QPAB-E anion separation membrane.

[0103] 2. Apply the 50% H 1 -QPAB-E anion separation membrane prepared in this example to the electrodialysis separation of F - / SO 4 2- , Br - / SO 4 2- , NO 3 - / SO 4 2- .

[0104] The electrodialysis method is the same as that in Comparative Example 1.

[0105] The test results are shown in the following table:

[0106]

[0107] In summary, the anion separation membrane prepared in this example achieved a significant improvement in ion separation efficiency.

[0108] As can be seen from the above examples, a high-loading HOFs mixed matrix membrane based on a solvent bridging strategy prepared by the present invention has excellent anion sieving performance, is suitable for a variety of anion separation systems at the same time, has superior separation performance, and achieves a significant improvement in the sieving efficiency of target ions. It has broad application prospects in the fields of extraction and recovery of high-value ion resources, environmental remediation, and treatment of high-salt wastewater.

[0109] The specific embodiments described above are only a preferred example of the present invention, and the protection scope of the present invention should not be limited thereto. Any person skilled in the art with corresponding technical knowledge in the technical field of the present invention can, without departing from the core idea and technical solution of the present invention, make equivalent substitutions or reasonable changes to the disclosed technical content of the present invention. These substitutions and changes should all be regarded as being included within the protection scope of the present invention.

Claims

1. A high-load hydrogen-bonded organic framework mixed matrix membrane based on a solvent bridging strategy, characterized in that: Using quaternary ammonium anion exchange membrane AEM as the base membrane, polyaminotriazine hydrogen-bonded organic framework HOFs as the modifier, and asymmetric disubstituted halogenated acid as the bridging solvent, based on the principle that the acid groups in the asymmetric disubstituted halogenated acid molecules interact electrostatically with the quaternary ammonium groups of the AEM base membrane and the halogens interact hydrogen-bond with the amino groups of HOFs, the bridging of the AEM base membrane and HOFs is achieved, the compatibility of the AEM base membrane and HOFs is promoted, the loading amount of HOFs on the AEM base membrane is increased, and a high-loading HOFs mixed matrix membrane is prepared.

2. The high-load hydrogen-bonded organic framework mixed matrix membrane based on solvent bridging strategy according to claim 1, characterized in that: The quaternary ammonium anion exchange membrane AEM has the following structural formula: ； Wherein, R2 is H or an alkyl group with 1-7 C atoms; Ar1 is an aromatic hydrocarbon group, and the aromatic hydrocarbon group has the following structure , , and One of them.

3. The high-load hydrogen-bonded organic framework mixed matrix membrane based on solvent bridging strategy according to claim 1, characterized in that: The polyaminotriazine hydrogen bond organic framework HOFs modifier has the following structure , , and One of; Wherein, R3 is H or an alkyl group with 1-2 C atoms; Ar2 is an aromatic hydrocarbon group, and the aromatic hydrocarbon group has the following structure , and One of; DAT1 and DAT2 have the following structures: 。 4. The high-load hydrogen-bonded organic framework mixed matrix membrane based on solvent bridging strategy according to claim 1, characterized in that: The asymmetric disubstituted halogenated acid bridging solvent has the following structural characteristics: X n —R1—AH m Wherein X is one or a combination of two or more of F, Cl, Br, and I, and n is 1-3; R1 is an alkyl group having 1 to 20 carbon atoms; AH is a carboxylic acid group, a sulfonic acid group or a phosphoric acid group, and m is 1-3.

5. The high-load hydrogen-bonded organic framework mixed matrix membrane based on solvent bridging strategy according to claim 1, characterized in that: The asymmetric disubstituted halogenated acid bridging solvent includes but is not limited to trifluoroacetic acid, trifluoromethanesulfonic acid, trifluoropropionic acid, dichloroacetic acid, and trichloroacetic acid.

6. The high-load hydrogen-bonded organic framework mixed matrix membrane based on solvent bridging strategy according to claim 1, wherein the preparation method thereof comprises the following steps: S1: AEM and halogenated acid are mixed in a mass ratio of 1: (1-20), homogenized and allowed to stand for 1-6 h until the bonding between the functional groups is completed, which is recorded as solution A; S2: HOFs and halogenated acid are mixed in a mass ratio of 1:(1-20), homogenized and allowed to stand for 1-6 h until the bonding between the functional groups is completed, which is recorded as solution B; S3: Mix solution A and solution B at a mass ratio of A:B=1:(0.1-0.5), and let stand for 1-6 hours after homogenization to complete the bridging between the functional groups to obtain a clear transparent film liquid. Smear the transparent film liquid on a glass plate, and evaporate the solvent at 20℃-80℃ to obtain a high-load HOFs mixed matrix membrane based on the solvent bridging strategy.

7. A high-load hydrogen-bonded organic framework mixed matrix membrane based on a solvent bridging strategy as described in any one of claims 1 to 6 for anion separation; The anion is Cl - / SO4 2- , F - / SO4 2- ,Br - / SO4 2- , NO3 - / SO4 2- One or more of the above, wherein the anion separation is carried out by electrodialysis, and the electrodialysis current density is 0.1-20 mA cm -2 .

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