CN115593037A

CN115593037A - Protein pollution resistant high anion conduction electrodialysis anion exchange membrane and preparation method and application thereof

Info

Publication number: CN115593037A
Application number: CN202211202326.3A
Authority: CN
Inventors: 李秀华; 王娟; 余以刚; 刘锦帅
Original assignee: South China University of Technology SCUT
Current assignee: South China University of Technology SCUT
Priority date: 2022-09-29
Filing date: 2022-09-29
Publication date: 2023-01-13

Abstract

The invention discloses a protein pollution resistant high anion conduction electrodialysis anion exchange membrane and a preparation method and application thereof. The preparation method comprises the steps of firstly preparing the anti-fouling calcium alginate sodium hydrogel ultrathin membrane with one-way gradient crosslinking, horizontally coating a poly 2,6-dimethylphenylene ether based serial dication ionomer solution on one surface of the anti-fouling calcium alginate sodium hydrogel ultrathin membrane, horizontally overturning and attaching the other piece of anti-fouling calcium alginate sodium hydrogel ultrathin membrane, constructing a composite membrane with a sandwich structure, removing volatile components, and fully soaking in distilled water; the invention effectively solves the problems of instability of an anti-pollution structure of the existing modified anion exchange membrane and the contradiction that a homogeneous ionomer membrane cannot give consideration to both the anti-pollution performance and the conductivity, obtains the protein pollution resistant compact anion exchange membrane with good basic performance and high anion conductivity, and meets the requirement of the desalting and electrodialysis process of a saliferous protein system on the comprehensive performance of the anion exchange membrane.

Description

Protein pollution resistant high anion conduction electrodialysis anion exchange membrane and preparation method and application thereof

Technical Field

The invention relates to a preparation method of a protein pollution resistant high anion conduction electrodialysis anion exchange membrane, and the protein pollution resistant high anion conduction electrodialysis anion exchange membrane prepared by the preparation method is suitable for the protein system electrodialysis desalination process.

Background

The Electrodialysis (ED) technology uses an external electric field as a driving force, and utilizes the selective permeability of an Ion Exchange Membrane (IEM) to realize the directional and selective migration of anions and cations in Anion Exchange Membranes (AEMs) and Cation Exchange Membranes (CEMs), thereby achieving the purposes of separating, concentrating and purifying electrolyte solution. With the improvement and innovation of the performance of the ion exchange membrane and the electrodialysis device, the ED technology is widely extended to new fields of food industry, bioengineering and the like from the fields of early seawater desalination, chemical wastewater treatment and the like, and is an important link of clean production. However, the ED technology is often applied to the treatment of a salt-containing water-rich neutral solution in which anions and cations coexist and organic matter is mixed. Complex aqueous solution systems, structural characteristics of the film and the like, and pollutants are easily deposited on the surface of the film or enter the film to form pollution, so that the performance of the film is reduced. And most organic contaminants are negatively charged, resulting in surface electropositive anion exchange membranes that are more susceptible to contamination than cation exchange membranes. At present, the effective way to solve membrane pollution is to use the frequent reverse Electrodialysis (EDR) technique, i.e. to switch the positive and negative electrodes of ED at regular intervals, the method can automatically clean the dirt formed on the surfaces of the ion exchange membrane and the electrode, but the technology has the problems of complicated process, shortened membrane life, high cost and the like, and the pollution of IEM can not be eradicated. In recent years, to meet the development requirements of modern electrodialysis technology, anion exchange membranes with anti-pollution capability are developed as one of the hot spots of gradual membrane research.

Related studies demonstrated increased membrane surface hydrophilicity and negative chargeDensity and the like can effectively improve the anti-pollution capability of AEMs, the hydrophilicity of the surface of the membrane is increased, the interaction between the hydrophobic structures of the membrane and pollutants is inhibited, and the electronegative surface is constructed on the outer side of the membrane through modification, so that the electrostatic repulsion between the anion exchange membrane and the pollutants is increased. At present, the main work is dedicated to constructing a hydrophilic electronegative antifouling layer on one side surface of the existing commercial membrane. A reported method for establishing a surface antifouling layer is oxidative coupling of a dopamine sulfonic acid derivative (A. Lejaazu-

Y.zhao, s.molina, e.garci a-Calvo, b.van der Bruggen, alternating current enhanced location of a monogenic selective for establishing exchange networks with anti-aging properties, sep.pure.technol.229 (2019) 115807. Ruan, Z.ZHEN, J.Pan, C.Gao, B.Van der Bruggen, J.Shen, muscle-embedded polymerized polyelectrolyte coating on exchange change membrane for improving polyelectrolyte and anti-fouling property, J.Memb.Sci.550 (2018) 427-435), solution deposition of negatively charged polyelectrolytes (R.Cao, S.Shi, Y.Li, B.xu, Z.ZHao, F.Ann.H.Cao, Y.Wang, the properties and anti-fouling property of exchange membranes modified by and polymerized polyelectrolyte (sodium 4-styrene), collagen A.895878. Asp). ) Or electrodeposition (Z.ZHao, H.Cao, S.Shi, Y.Li, L.Yao, characterization of exchange modified by electrochemical deposition of polymeric conditioning functional groups, degradation.386 (2016) 58-66. ) And cationic and anionic polyelectrolyte dc electric field electrodeposition layer-by-layer assembly techniques (s.mulatii, r.takagi, a.fujii, y.ohmukai, h.matsuyama, simple improvement of the single action selection and anti-aging properties of an exchange membrane in an electrochemical process, using a polymeric electrolyte layer deposition, j.membrane.sci.431 (2013) 113-120. ) And alternating current field electrodeposition layer-by-layer assembly techniques (Y.ZHao, C.Gao, B.Van Der Bruggen, technology-driven layer-by-layer assembly of a membrane for selective separation of monomeric and anti-pollution, nanoscale.11 (R))2019) 2264. ) However, the antifouling layer and the anion exchange membrane body built by the method are only invaded by electrostatic adsorption or a shallow surface layer, the bonding strength between the antifouling layer and the anion exchange membrane body is low, the antifouling layer can be dropped due to current impact, rapid solution stirring and the like in the ED or EDR process, and the AEMs surface resistance is inevitably increased due to the building of the antifouling layer, so that the energy consumption is increased, and the membrane ED desalting performance is reduced. Liu et al (Y.Liu, J.Liao, G.Peng, C.Dong, S.Yang, J.Shen, poly (vinyl chloride) -Based Anion-Exchange Membrane with High-inhibiting polymerization for electrochemical analysis Application, ACS appl.Polym.Mater.3 (2021) 2529-2540.) control the Membrane preparation process of the crosslinked polyvinyl chloride AEMs, so that the crosslinked ionomer body is rich in hydrophilic secondary amine groups containing lone pair electrons, and further the hydrophilicity and the negative charge density of the Membrane surface are adjusted to achieve a certain effect of resisting SDBS pollution, but the selective permeability of AEMs anions is reduced, and the current efficiency of c-QPVC-3N with the best performance in the presence of SDBS is only 65.8%. The Shen group uses polyvinyl alcohols rich in hydrophilic lone pair-containing OH groups to prepare crosslinked quaternized polyvinyl alcohols AEMs, the ED performance of which in the presence of SDBS is best for the antifouling membranes QPVA3 is still lower than that of the commercial membranes JAM-II-5 (Y. Liu, S. Yang, Y. Chen, J. Liao, J. Pan, A. Sotto, J. Shen, preparation of water-based and-exchange membrane from PVA for anti-fouling in the electrochemical analysis process, J. Memb. Sci.570-571 (2019) 130-138). The two homogeneous ionomers have stable anti-fouling membrane structure, but achieve the anti-fouling purpose by partly sacrificing the ED performance.

In the food industry and bioengineering field, severe macromolecular contamination can occur when performing electrodialysis of protein or polypeptide-containing solutions, while the charge centers and molecular weights of proteins and polypeptides are larger than those of SDBS, resulting in great differences in the contaminating behavior of proteins to AEMs and in the contamination of SDBS with small organic molecules. The application of AEMs resisting SDBS pollution to the ED desalting and stain resisting effect and ED performance of a protein system is difficult to predict.

Disclosure of Invention

In order to overcome the problems of instability of an anti-pollution structure of the existing modified anion exchange membrane and the problem that a homogeneous ionomer membrane cannot easily give consideration to both the anti-pollution performance and the conductivity, the invention aims to provide a high-anion-conduction electrodialysis anion exchange membrane with good basic performance and protein pollution resistance and a preparation method thereof.

The invention also aims to provide the application of the protein pollution resistant high anion conduction electrodialysis anion exchange membrane in electrodialysis desalination of a protein system.

In order to achieve the above object, the present invention provides the following technical solutions.

A method for preparing a high anion conduction electrodialysis anion exchange membrane resistant to protein contamination, comprising the following steps:

1) Evenly spreading a Sodium Alginate (SA) solution on a glass plate, evenly spraying a calcium chloride solution on the sodium alginate solution, and reacting at room temperature to form the antifouling calcium alginate sodium hydrogel ultrathin film with unidirectional gradient crosslinking;

2) Dissolving brominated poly 2,6-dimethylphenylene ether (BPPO) in N-methylpyrrolidone (NMP), adding 1,4-diazabicyclo [2,2,2] octane (DABCO) based monocationic derivative, stirring, and reacting at normal temperature for 48-72 h to obtain a viscous poly 2,6-dimethylphenylene ether based tandem dicationic ionomer solution;

3) Coating a poly 2,6-dimethylphenylene ether based serial dicationic ionomer solution on one surface of an anti-fouling calcium alginate sodium hydrogel ultrathin film, and covering another anti-fouling calcium alginate sodium hydrogel ultrathin film on the poly 2,6-dimethylphenylene ether based serial dicationic ionomer liquid film to construct a sandwich structure composite film; and removing volatile components from the composite membrane to obtain a dry membrane, and fully soaking the dry membrane in distilled water to obtain the protein pollution resistant high anion conduction electrodialysis anion exchange membrane.

To further achieve the object of the present invention, preferably, in step (1), the concentration of the sodium alginate solution is 1wt% to 2wt%; the solution concentration of the calcium chloride solution is 0.05 mol/L-0.10 mol/L.

Preferably, in the step (1), the dosage of the sodium alginate solution on each square centimeter of the antifouling calcium sodium alginate hydrogel ultrathin membrane is 0.04 mL-0.05 mL, and the volume ratio of the calcium chloride solution to the sodium alginate solution is 4-6:1.

preferably, in step (1), the reaction time at room temperature is 15 to 25 minutes.

Preferably, in step (2), the bromomethylation degree of the brominated poly 2,6-dimethylphenylene ether is 0.2-0.4; after the brominated poly (2,6-dimethylphenylene oxide) is dissolved in N-methyl pyrrolidone, the solid content of the brominated poly (2,6-dimethylphenylene oxide) is 0.10 g/mL-0.15 g/mL.

Preferably, in step (2), the molar ratio of bromomethyl of brominated poly 2,6-dimethylphenylene ether, 1,4-diazabicyclo [2,2,2] octane monocationic derivative is 1:1, the rotating speed of the stirring is 100 rpm-200 rpm; the concentration of the poly 2,6-dimethylphenylene ether based serial dicationic ionomer solution is 11.8-16.7 wt%.

Preferably, in step (2), 1,4-diazabicyclo [2,2,2]The octane radical monocationic derivative is 1-hexyl-1,4-diazabicyclo [2,2,2]Octyl ammonium bromide

Or 1-methyl-1,4-diazabicyclo [2,2,2]Octyl ammonium iodide

Preferably, in the step (3), 0.04-0.05mL of the solution of the poly 2,6-dimethylphenylene ether based serial dicationic ionomer is coated on each square centimeter of the antifouling calcium sodium alginate hydrogel ultrathin film; the volatile component removal is realized by heating for 40-48h at 60-65 ℃.

An anti-protein-contamination high anion-conduction electrodialysis anion exchange membrane is prepared by the preparation method; at room temperature, the ion selective permeability of the high anion conduction electrodialysis anion exchange membrane is 90-93 percent, the water contact angle is 54-59 degrees, and the surface resistance is 2.1 omega/cm ² ～2.6Ω/cm ² The tensile strength is 14.5MPa to 20.4MPa, the water absorption rate is 18.6 percent to 24.6 percent, and the swelling rate is 4.2 percent to 10.4 percent.

The protein pollution resistant high anion conduction electrodialysis anion exchange membrane is applied to electrodialysis desalination of a protein system.

Compared with the prior art, the invention has the following advantages and beneficial effects:

1) The invention realizes the control two-way interpenetration of the high-functionality tandem dicationic ionomer and the protein pollution-resistant calcium sodium alginate hydrogel and the ionomer body solidification by pre-designing the one-way gradient cross-linking structure and by means of thermal driving, and effectively solves the problem of the instability of the anti-fouling modified structure of the anion exchange membrane caused by the prior modification technology.

2) The invention constructs a sandwich structure composite membrane taking a high-functionality poly 2,6-dimethylphenylene ether group serial dication ionomer solution membrane as a core, realizes the control of a bidirectional interpenetrating structure and an ionomer body structure with protein pollution resistant calcium sodium alginate hydrogel by controlling the structure and the composition amount of the high-functionality serial dication ionomer, solves the problem that a homogeneous ionomer anti-fouling membrane cannot give consideration to both the pollution resistance and the conductivity, obtains a protein pollution resistant high anion conductive compact anion exchange membrane, and has good mechanical properties.

3) At room temperature, the protein pollution resistant high anion conduction electrodialysis anion exchange membrane has the ion selective permeability of 90-93 percent, the water contact angle of 54-59 degrees and the surface resistance of 2.1 omega/cm ² ～2.6Ω/cm ² The tensile strength is 14.5MPa to 20.4MPa, the water absorption is 18.6 percent to 24.6 percent, and the swelling ratio is 4.2 percent to 10.4 percent, so that the requirements of the desalting and electrodialysis process of a saliferous protein system on the comprehensive performance of the anion exchange membrane can be met.

Drawings

FIG. 1 shows the anion-exchange membrane QPPO-DABCO obtained in example 1 ₁ -CA ₁ Cross-sectional energy spectrum of the upper anti-fouling layer.

FIG. 2 shows the anion-exchange membrane QPPO-DABCO obtained in example 1 ₁ -CA ₁ 700 times scanning electron micrograph of the cross section.

FIG. 3 shows the anion-exchange membrane QPPO-DABCO obtained in example 1 ₁ -CA ₁ Cross-sectional energy spectrum of the lower anti-fouling layer.

FIG. 4 shows the anion-exchange membrane QPPO-DABCO obtained in example 1 ₁ -CA ₁ The section of the upper anti-fouling layer is 30000 times of a scanning electron microscope image.

FIG. 5 shows the anion-exchange membrane QPPO-DABCO obtained in example 1 ₁ -CA ₁ 30000 times of scanning electron micrograph of the center of the cross section.

FIG. 6 shows the anion exchange membrane QPPO-DABCO obtained in example 1 ₁ -CA ₁ 30000 times of the cross section of the lower anti-fouling layer.

FIG. 7 shows QPPO-DABCO anion-exchange membrane obtained in example 2 ₁ -CA ₂ Cross-sectional energy spectrum of the upper anti-fouling layer.

FIG. 8 shows the anion-exchange membrane QPPO-DABCO obtained in example 2 ₁ -CA ₂ 700 times scanning electron micrograph of the cross section.

FIG. 9 shows the anion-exchange membrane QPPO-DABCO obtained in example 2 ₁ -CA ₂ Cross-sectional spectra of the lower anti-fouling layer.

FIG. 10 shows QPPO-DABCO as an anion exchange membrane obtained in example 2 ₁ -CA ₂ The section of the upper anti-fouling layer is 30000 times of a scanning electron microscope image.

FIG. 11 shows the anion exchange membrane QPPO-DABCO obtained in example 2 ₁ -CA ₂ 30000 times of scanning electron micrograph of the center of the cross section.

FIG. 12 shows QPPO-DABCO anion-exchange membrane obtained in example 2 ₁ -CA ₂ 30000 times of the cross section of the lower anti-fouling layer.

FIG. 13 shows QPPO-DABCO anion-exchange membrane obtained in example 3 ₁ -CA ₃ The cross section energy spectrum of the upper anti-fouling layer.

FIG. 14 shows QPPO-DABCO anion-exchange membrane obtained in example 3 ₁ -CA ₃ 700 times scanning electron micrograph of the cross section.

FIG. 15 shows the anion-exchange membrane QPPO-DABCO obtained in example 3 ₁ -CA ₃ Cross-sectional energy spectrum of the lower anti-fouling layer.

FIG. 16 shows the QPPO-DABCO anion exchange membrane obtained in example 3 ₁ -CA ₃ The section of the upper anti-fouling layer is 30000 times of a scanning electron microscope image.

FIG. 17 shows an anion-exchange membrane Q obtained in example 3PPO-DABCO ₁ -CA ₃ Scanning electron micrograph of 30000 times of center of cross section.

FIG. 18 shows QPPO-DABCO anion-exchange membrane obtained in example 3 ₁ -CA ₃ The cross section of the lower anti-fouling layer is 30000 times of a scanning electron microscope image.

Detailed Description

The technical solution of the present invention is further described by combining specific examples, but the embodiments of the present invention are not limited by the examples, and any other changes, modifications, substitutions, combinations, and simplifications which do not depart from the spirit and principle of the present invention should be regarded as equivalent substitutions and are included in the scope of the present invention.

The invention achieves the purpose of resisting protein pollution by repelling electronegative protein through the inherent hydrophilicity and electronegativity of the surface of the calcium sodium alginate hydrogel ultrathin membrane. The control bidirectional interpenetrating of the high-functionality series dication ionomer and the calcium sodium alginate hydrogel and the ionomer body solidification are realized by means of thermal driving through the pre-designed unidirectional gradient cross-linking structure, the instability of an anti-pollution modification structure of an anion exchange membrane caused by the existing modification technology is effectively solved, the contradiction between the anti-pollution property and the conductivity of a homogeneous ionomer anti-pollution membrane is difficult to be considered, the protein pollution resistant high-anion conduction compact anion exchange membrane is obtained, the series of membranes have good mechanical properties, and the requirements of the desalting and electrodialysis process of a salt-containing protein system on the comprehensive properties of the anion exchange membrane can be met.

Preferably, the method for preparing the protein contamination resistant high anion conduction electrodialysis anion exchange membrane comprises the following steps:

(1) One-way gradient cross-linked anti-fouling calcium sodium alginate hydrogel ultrathin membrane CA _x Preparation of

Uniformly spreading appropriate amount of Sodium Alginate (SA) solution in horizontally placed glass plate fixing region, and adding calcium chloride (CaCl) ₂ ) The solution is evenly sprayed on an SA liquid film and reacts at room temperature to form the unidirectional gradient crosslinked antifouling calcium sodium alginate hydrogel ultrathin membrane CA _x Where x =1,2,3. The anti-pollution calcium sodium alginate hydrogel prepared by the methodFilm CA _x The unidirectional gradient cross-linked structure of the polymer can be controlled by controlling CA _x Different concentrations of SA and CaCl during preparation ₂ By carrying out a film-making process, e.g. one of the combinations CA ₁ 1wt% of SA solution, caCl ₂ The solution is 0.10mol/L; and as CA ₂ The corresponding solution combination was 2wt% SA,0.10mol/L CaCl ₂ (ii) a E.g. CA ₃ The corresponding solution combination was 2wt% SA,0.05mol/LCaCl ₂ 。

(2) Poly 2,6-dimethylphenylene ether based tandem dicationic ionomer QPPO-DABCO _y Preparation of the solution

Brominated poly 2,6-dimethylphenylene ether (BPPO) of a particular degree of bromomethylation is dissolved in N-methylpyrrolidone (NMP) and 1,4-diazabicyclo [2,2,2] is added]Octane (DABCO) based monocationic derivative is stirred and reacted for 48 to 72 hours at normal temperature to obtain brown viscous poly 2,6-dimethylphenylene ether based tandem dicationic ionomer QPPO-DABCO _y A solution, wherein y =1,2.

(3) Preparation of stable protein pollution-resistant high-conductivity electrodialysis anion exchange membrane

Taking poly 2,6-dimethylphenylene ether based tandem dicationic ionomer QPPO-DABCO _y Pouring the solution in the step (1) to obtain a piece of wet CA placed in parallel _x Preferably, e.g., CA per square centimeter _x Membrane QPPO-DABCO _y The dosage of the solution is 0.4mL, so that QPPO-DABCO is added _y The solution was cast naturally and then the other piece of CA was cast _x Horizontal flip overlay in QPPO-DABCO _y Constructing a sandwich structure composite membrane taking a poly 2,6-dimethylphenylene ether series bi-cation ionomer liquid membrane as a core on a liquid membrane, preferably heating the composite membrane at 60 ℃ for 48h to slowly remove volatile components, and accelerating the bidirectional vertical diffusion of an NMP interface through thermal induction in the initial heating stage to obtain a core layer ionomer QPPO-DABCO _y Stepwise dissolution directed implantation of CA _x Anti-fouling layer to obtain ionomer and CA _x Partially interpenetrating double-sided anti-fouling structure, and complete CA of water and NMP volatilization along with prolonged heating time _x And curing with an ionomer body to obtain a dry film with a stable anti-fouling structure on two sides, and fully soaking the dry film in distilled water to obtain the protein-pollution-resistant high-anion-conduction electrodialysis anion exchange membrane QPPO-DABCO _y -CA _x Wherein x =1,2,3, y =1,2.

The protein pollution resistant high anion conduction electrodialysis anion exchange membrane obtained by the invention has the advantages that the ion selective permeability is 90-93%, the water contact angle is 54-59 degrees, and the surface resistance is 2.1 omega/cm at room temperature ² ～2.6Ω/cm ² The tensile strength is 14.5MPa to 20.4MPa, the water absorption rate is 18.6 percent to 24.6 percent, and the swelling rate is 4.2 percent to 10.4 percent.

The performance parameters of the ion exchange membrane in the embodiment of the invention are mainly determined by references H.Xie, J.Pan, B.Wei, J.Feng, S.Liao, X.Li, Y.Yu, anti-fouling exchange membrane for electrochemical analysis by in-situ interaction of the ion to digital cross-linking network of Ca-Na algorithm, degradation.505 (2021) 115005.

Determination of ion selectivity: the assay was performed using a home-made two-compartment device. The membrane sample 5X 5cm was soaked in 0.5M sodium chloride solution for 48h and then removed for testing. Fixing the anion exchange membrane to be detected in the middle of the compartment, adding 0.5M sodium chloride solution into one end of the compartment, adding 0.1M sodium chloride solution into the other end of the compartment, and eliminating the concentration polarization phenomenon through violent stirring. The voltage across the membrane was measured with a silver/silver chloride connected multimeter. The ion selectivity P is calculated as follows:

wherein E _{measured representation} Measuring the resulting membrane voltage, E _theroetical Representing the theoretical membrane voltage.

The water contact angle of the film surface is measured by a German DATAPHYSICS OCA Micro surface contact angle tester, and the volume of each water drop is 3 mu L.

Measurement of sheet resistance: the test was performed using a galvanostatic method in a homemade four-compartment device comprising two electrode compartments and two intermediate compartments. The membrane sample 5X 5cm was soaked in 0.5M sodium chloride solution for 48h and then removed for testing. Respectively using 2 Nafion-

The cation exchange membrane separates the electrode solution in the electrode chamber from the sodium chloride aqueous solution chamber. Filled with 0.3M sodium sulphate solution, the intermediate chamber with 0.5M sodium chloride solution, and an electrochemical workstation (IviumStat) to provide a constant current density (5 mA cm) ^-2 ). And testing the resistance of the anion exchange membrane to be tested and the resistance of the anion exchange membrane without the anion exchange membrane. R of the film to be measured _m The calculation formula is as follows:

R _m ＝R _cell -R _sol

wherein R is _cell And R _sol The electrical resistance measured with and without an anion exchange membrane is shown separately.

Measurement of Water absorption and swelling ratio: the membrane sample 3 x 3cm was vacuum dried at 60 ℃ for 48h, then soaked in deionized water at room temperature for 24h, the mass of the wet film was quickly weighed after quickly wiping off the water on the film surface with filter paper and the two-dimensional size of the wet film was measured. The calculation formula of the water absorption WU and the swelling SR of the ion exchange membrane is as follows:

wherein W _wet Denotes the mass of the wet film, W _dry Denotes the quality of the dry film, L _wet Denotes the length of the wet film, L _dry The length of the dry film is shown.

Determination of tensile Strength: the wet film samples were tested at 5X 0.5cm using an Instron M3300 electronic Universal testing machine, the film stretching rate being 5mm/min.

Determination of the electrodialysis performance: the electrodialysis performance test is carried out in a self-made electrodialysis device which consists of a concentration chamber, a desalination chamber and two electrode chambers, and 2 Nafion-

And 1 anion exchange membrane to be detected isolates the electrode solution in the electrode chamber from the sodium chloride aqueous solution in the concentration chamber and the salted egg white solution in the desalting chamber. The effective membrane area is 20.25cm ² The film spacing was 9mm. 300mL of 0.30mol/L sodium sulfate solution is introduced and circulated in the polar room, 100mL of 0.017mol/L sodium chloride solution is introduced and circulated in the concentration room, and 100mL of salted egg clear liquid is introduced and circulated in the desalting room. After the device is filled with the solution, the solution is kept circulating, the device is balanced for 30min without power supply, and then 10mA cm is introduced ^-2 And (5) starting a salted egg white electrodialysis desalination experiment for 2h at constant current. The conductivity value of the solution in the concentration chamber is measured by using a conductivity meter, and the voltage value of the test cell is measured by using a universal meter. The current efficiency η is calculated as follows:

wherein Z represents the valence of the chloride ion, C ₀ And C _t Respectively represents the concentration of the dilution tank at 0 and t of the desalting time, V _t The volume of the concentration tank when the salt time is t is shown, F is the Faraday constant, N is the number of desalting tanks, I is the current, and t is the desalting time.

Example 1

(1) Unidirectional gradient cross-linked antifouling calcium sodium alginate hydrogel ultrathin membrane CA ₁ Preparation of

10mL of the SA solution 10% by weight was uniformly laid in a horizontally placed glass plate fixing area of 15 cm. Times.15 cm, and 50mL of 0.10mol/L CaCl ₂ The solution is evenly sprayed on an SA liquid film and reacts for 20 minutes at room temperature to form the unidirectional gradient cross-linked antifouling calcium sodium alginate hydrogel ultrathin film CA ₁ 。

(2) Poly 2,6-dimethylphenylene ether based tandem dicationic ionomer QPPO-DABCO ₁ Preparation of the solution

3g BPPO (-CH) with a bromomethylation degree of 0.40 ₂ Br,7.91 mmol) was dissolved in an appropriate 27mL of NMP, the BPPO content in the reaction mixture was 0.11g/mL, 1-hexyl-1,4-diazabicyclo [2,2,2] was added]Octyl ammonium bromide

(2.1930g, 7.91mmol) is stirred vigorously at the rotation speed of 100rpm and reacted at normal temperature for 48 hours to obtain brown viscous poly 2,6-dimethylphenylene ether based tandem dicationic ionomer QPPO-DABCO ₁ The concentration of the solution was 15.76wt%.

Taking poly 2,6-dimethylphenylene ether group to serially connect dicationic ionomer QPPO-DABCO ₁ 9mL of the solution was poured into the wet CA prepared in step (1) in parallel ₁ Let QPPO-DABCO ₁ The solution was cast naturally and then the other piece of CA was cast ₁ Horizontal flip overlay in QPPO-DABCO ₁ Constructing a sandwich structure composite membrane taking a poly 2,6-dimethylphenylene ether based serial dicationic ionomer liquid membrane as a core on the liquid membrane, wherein each square centimeter of CA ₁ Membrane QPPO-DABCO ₁ The using amount of the solution is 0.04mL, the composite membrane is heated at 60 ℃ for 48h to slowly remove volatile components, and the interlayer ionomer QPPO-DABCO is subjected to bidirectional vertical diffusion of an NMP interface through thermal induction acceleration in the initial heating stage ₁ Stepwise dissolution directed implantation of CA ₁ Anti-fouling layer to obtain ionomer and CA ₁ Partially interpenetrating double-sided anti-fouling structure, complete CA along with extension of heating time and NMP volatilization ₁ And curing an ionomer body to obtain a dry film with a stable anti-fouling structure on two sides, and fully soaking the dry film in distilled water to obtain the protein-pollution-resistant high-anion-conduction electrodialysis anion exchange membrane QPPO-DABCO ₁ -CA ₁ 。

Partial QPPO-DABCO ₁ -CA ₁ Cutting into sample strips of 5mm × 10mm, quenching in liquid nitrogen, scanning the sample section by 700 times under magnification to obtain a sample section overall view of FIG. 2, and illustrating QPPO-DABCO ₁ -CA ₁ The structure is uniform, and the anti-pollution structure and the ionomer body membrane are integrated. Respectively performing energy spectrum analysis on the 15 μm depth sections of the upper and lower anti-fouling layers shown in FIG. 2 to obtain QPPO-DABCO shown in FIG. 1 ₁ -CA ₁ Cross-sectional energy spectrum of the upper antifouling layer and QPPO-DABCO shown in FIG. 3 ₁ -CA ₁ The cross-section energy spectrum of the lower anti-fouling layer, the appearance of Ca, cl, br, C, N and O signals in the two energy spectra of figure 1 and figure 3 shows QPPO-DABCO ₁ And upper and lower CA ₁ There is a good interpenetration structure. Scanning the 15 μm depth cross section and the middle part of the cross section of the upper and lower antifouling layers shown in FIG. 2 by 30000 times to obtain QPPO-DABCO shown in FIG. 4 ₁ -CA ₁ The cross section of the upper anti-fouling layer is 30000 times of that of the upper anti-fouling layer, and the QPPO-DABCO shown in figure 5 ₁ -CA ₁ 30000 times scanning electron microscope image of the center of the cross section and QPPO-DABCO shown in FIG. 6 ₁ -CA ₁ The cross section of the lower anti-fouling layer is 30000 times of a scanning electron microscope image, and the electron microscope results of the images 4-6 show that the upper anti-fouling layer, the lower anti-fouling layer and the high-conductivity ionomer body film are uniform in microstructure and stable in structure.

Protein contamination resistant high anion conduction electrodialysis anion exchange membrane QPPO-DABCO ₁ -CA ₁ The basic properties of (A): at room temperature, the ion selective permeability is 92%, the water contact angle is 58.35 degrees, and the surface resistance is 2.60 omega/cm ² The tensile strength was 20.35MPa, the water absorption was 20.67%, and the swelling ratio was 4.26%.

QPPO-DABCO ₁ -CA ₁ ED desalting performance of salted egg white: current efficiency η =80.28% (10 mA/cm) ² )；QPPO-DABCO ₁ Salted egg white ED desalting performance: current efficiency η =75.65 (10 mA/cm) ² ) (ii) a Japanese ASTOM commercial membrane AMX salted egg white ED desalting performance: current efficiency η =78.21%; QPPO-DABCO ₁ -CA ₁ The ED desalting performance of the salted egg white is superior to QPPO-DABCO ₁ Description of QPPO-DABCO ₁ -CA ₁ QPPO-DABCO with resistance to protein contamination ₁ -CA ₁ ED desalting performance of the salted egg white is superior to AMX explanation QPPO-DABCO ₁ -CA ₁ Has high anion conductivity.

Example 2

(1) One-way gradient cross-linked anti-fouling calcium sodium alginate hydrogel ultrathin membrane CA ₂ Preparation of

2wt% of SA solution 10mL was uniformly spread in a horizontally placed glass plate holding area of 15 cm. Times.15 cm, and 50mL of 0.10mol/L CaCl ₂ The solution is evenly sprayed on an SA liquid film and reacts for 20 minutes at room temperature to form the unidirectional gradient cross-linked antifouling calcium sodium alginate hydrogel ultrathin film CA ₂ 。

(2) Poly 2,6-dimethylphenylene ether based tandem dicationic ionomeric polymersSubstance QPPO-DABCO ₁ Preparation of the solution

(2.1930g, 7.91mmol) is stirred vigorously at the rotation speed of 150rpm and reacted at normal temperature for 48 hours to obtain brown viscous poly 2,6-dimethylphenylene ether based tandem dicationic ionomer QPPO-DABCO ₁ The concentration of the solution was 15.76wt%.

Taking poly 2,6-dimethylphenylene ether based tandem dicationic ionomer QPPO-DABCO ₁ 9mL of the solution was poured into the wet CA prepared in step (1) in parallel ₂ Let QPPO-DABCO ₁ The solution was cast naturally and then the other piece of CA was cast ₂ Horizontal flip overlay in QPPO-DABCO ₁ Constructing a sandwich structure composite membrane taking a poly 2,6-dimethylphenylene ether based serial dicationic ionomer liquid membrane as a core on the liquid membrane, wherein each square centimeter of CA ₂ Membrane QPPO-DABCO ₁ The using amount of the solution is 0.04mL, the composite membrane is heated at 60 ℃ for 48h to slowly remove volatile components, and the interlayer ionomer QPPO-DABCO is subjected to bidirectional vertical diffusion at the NMP interface through thermal induction in the initial heating stage ₁ Stepwise dissolution directed implantation of CA ₂ Anti-fouling layer to obtain ionomer and CA ₂ Partially interpenetrating double-sided anti-fouling structure, and complete CA of water and NMP volatilization along with prolonged heating time ₂ And curing an ionomer body to obtain a dry film with a stable anti-fouling structure on two sides, and fully soaking the dry film in distilled water to obtain the protein-pollution-resistant high-anion-conduction electrodialysis anion exchange membrane QPPO-DABCO ₁ -CA ₂ 。

Partial QPPO-DABCO ₁ -CA ₂ Cutting into sample strips of 5mm × 10mm, quenching in liquid nitrogen, scanning the sample section by 700 times under magnification to obtain a sample section overall view of FIG. 8, and illustrating QPPO-DABCO ₁ -CA ₂ Uniform structure, anti-fouling structure and ionomer body membraneAre integrated into a whole. Respectively performing energy spectrum analysis on the 15-micron depth sections of the upper and lower anti-fouling layers shown in FIG. 8 to obtain QPPO-DABCO shown in FIG. 7 ₁ -CA ₂ Cross-sectional energy spectrum of the upper antifouling layer and QPPO-DABCO shown in FIG. 9 ₁ -CA ₂ The cross-section energy spectrum of the lower antifouling layer, and the appearance of Ca, cl, br, C, N and O signals in the two energy spectra of FIG. 7 and FIG. 9 show that QPPO-DABCO ₁ And upper and lower CA ₂ There is a good interpenetration structure. Scanning the 15 μm depth cross section and the middle part of the cross section of the upper and lower antifouling layers shown in FIG. 8 by 30000 times to obtain QPPO-DABCO shown in FIG. 10 ₁ -CA ₁ The cross section of the upper anti-fouling layer is 30000 times of that of the upper anti-fouling layer, and the QPPO-DABCO shown in figure 11 ₁ -CA ₂ 30000 times scanning electron microscope image of the center of the cross section and QPPO-DABCO shown in FIG. 12 ₁ -CA ₂ The cross section of the lower anti-fouling layer is 30000 times of a scanning electron microscope image, and the electron microscope results of the images 10-12 show that the upper anti-fouling layer, the lower anti-fouling layer and the high-conductivity ionomer body film are uniform in microstructure and stable in structure.

Protein contamination resistant high anion conduction electrodialysis anion exchange membrane QPPO-DABCO ₁ -CA ₂ The basic properties of (A): at room temperature, the ion selective permeability is 90.27%, the water contact angle is 55.83 degrees, and the surface resistance is 2.11 omega/cm ² The tensile strength was 16.22MPa, the water absorption was 18.69%, and the swelling ratio was 9.30%.

QPPO-DABCO ₁ -CA ₂ ED desalting performance of salted egg white: current efficiency η =84.86% (10 mA/cm) ² )；QPPO-DABCO ₁ Salted egg white ED desalting performance: current efficiency η =75.65 (10 mA/cm) ² ) (ii) a Commercial membrane AMX salted egg white ED desalting performance of ASTOM japan: current efficiency η =78.21%; QPPO-DABCO ₁ -CA ₂ The ED desalting performance of the salted egg white is superior to QPPO-DABCO ₂ Description of QPPO-DABCO ₁ -CA ₂ QPPO-DABCO with resistance to protein contamination ₁ -CA ₂ ED desalting performance of the salted egg white is superior to AMX explanation QPPO-DABCO ₁ -CA ₂ Has high anion conductivity.

Example 3

(1) One-way gradient cross-linked anti-fouling calcium sodium alginate hydrogel ultrathin membrane CA ₃ Preparation of

10mL of the SA solution 2wt% was uniformly laid on a horizontally placed glass plate holding area of 15 cm. Times.15 cm, and 50mL of 0.05mol/L CaCl ₂ The solution is evenly sprayed on an SA liquid film and reacts for 20 minutes at room temperature to form the unidirectional gradient cross-linked antifouling calcium sodium alginate hydrogel ultrathin film CA ₃ 。

(2.1930g, 7.91mmol) is stirred vigorously at the rotation speed of 200rpm and reacted at normal temperature for 48 hours to obtain brown viscous poly 2,6-dimethylphenylene ether based tandem dicationic ionomer QPPO-DABCO ₁ The concentration of the solution was 15.76wt%.

Taking poly 2,6-dimethylphenylene ether based tandem dicationic ionomer QPPO-DABCO ₁ 9mL of the solution was poured into the wet CA prepared in step (1) in parallel ₃ Let QPPO-DABCO ₁ The solution was cast naturally and then the other piece of CA was cast ₃ Horizontal flip overlay in QPPO-DABCO ₁ Constructing a sandwich structure composite membrane taking a poly 2,6-dimethylphenylene ether based serial dicationic ionomer liquid membrane as a core on the liquid membrane, wherein each square centimeter of CA ₃ Membrane QPPO-DABCO ₁ The using amount of the solution is 0.04mL, the composite membrane is heated at 60 ℃ for 48h to slowly remove volatile components, and the interlayer ionomer QPPO-DABCO is subjected to bidirectional vertical diffusion at the NMP interface through thermal induction in the initial heating stage ₁ Stepwise dissolution directed implantation of CA ₃ Anti-fouling layer to obtain ionomer and CA ₃ Partially interpenetrating double-sided anti-fouling structure, complete CA along with extension of heating time and NMP volatilization ₃ Solidifying with ionomer to obtain dry film with stable two-sided anti-fouling structure, soaking the dry film in distilled water to obtain anti-protein pollutionHigh anion-conducting electrodialysis anion exchange membrane QPPO-DABCO ₁ -CA ₃ 。

Partial QPPO-DABCO ₁ -CA ₃ Cutting into sample strips of 5mm × 10mm, quenching in liquid nitrogen, scanning the sample section by 700 times under magnification to obtain a sample section overall view of FIG. 14, which illustrates QPPO-DABCO ₁ -CA ₃ The structure is uniform, and the anti-pollution structure and the ionomer body membrane are integrated. Respectively performing energy spectrum analysis on 15 μm depth sections of the upper and lower antifouling layers shown in FIG. 14 to obtain QPPO-DABCO shown in FIG. 13 ₁ -CA ₃ Cross-sectional energy spectrum of the upper antifouling layer and QPPO-DABCO shown in FIG. 15 ₁ -CA ₃ The cross-section energy spectrum of the lower anti-fouling layer of (1), the appearance of Ca, cl, br, C, N, O signals in the two energy spectra of FIG. 13 and FIG. 15 shows QPPO-DABCO ₁ And upper and lower CA ₃ There is a good interpenetration structure. Scanning the 15 μm depth sections and the middle parts of the sections of the upper and lower antifouling layers shown in FIG. 14 by magnification of 30000 times to obtain QPPO-DABCO shown in FIG. 16 ₁ -CA ₃ The cross section of the upper anti-fouling layer is 30000 times of that of the upper anti-fouling layer, and the QPPO-DABCO shown in figure 17 ₁ -CA ₃ 30000 times of scanning electron micrograph of cross-section center and QPPO-DABCO shown in FIG. 18 ₁ -CA ₃ The cross section of the lower anti-fouling layer is 30000 times of a scanning electron microscope image, and the electron microscope results of the images 16-18 show that the upper anti-fouling layer, the lower anti-fouling layer and the high-conductivity ionomer body film are uniform in microstructure and stable in structure.

Protein contamination resistant high anion conduction electrodialysis anion exchange membrane QPPO-DABCO ₁ -CA ₃ The basic properties of (A): at room temperature, the ion selective permeability is 91.83%, the water contact angle is 58.60 DEG, and the surface resistance is 2.58 omega/cm ² The tensile strength was 14.48MPa, the water absorption was 18.65%, and the swelling ratio was 5.56%.

QPPO-DABCO ₁ -CA ₃ ED desalting performance of the salted egg white: current efficiency η =82.55% (10 mA/cm) ² )；QPPO-DABCO ₁ Salted egg white ED desalting performance: current efficiency η =75.65 (10 mA/cm) ² ) (ii) a Commercial membrane AMX salted egg white ED desalting performance of ASTOM japan: current efficiency η =78.21%; QPPO-DABCO ₁ -CA ₁ The ED desalting performance of the salted egg white is superior to QPPO-DABCO ₁ Description of QPPO-DABCO ₁ -CA ₃ QPPO-DABCO with resistance to protein contamination ₁ -CA ₃ The ED desalting performance of the salted egg white is superior to that of AMX (amino propyl pyrrolidone) -explained QPPO-DABCO ₁ -CA ₃ Has high anion conductivity.

Example 4

(1) One-way gradient cross-linked anti-fouling calcium sodium alginate hydrogel ultrathin membrane CA ₁ Preparation of

1% by weight of SA solution 5mL was uniformly spread in a horizontally placed glass plate fixing area of 10 cm. Times.10 cm, and 25mL0.10mol/L of CaCl was added ₂ The solution is evenly sprayed on an SA liquid film and reacts for 20 minutes at room temperature to form the unidirectional gradient cross-linked antifouling calcium sodium alginate hydrogel ultrathin film CA ₁ 。

(2) Poly 2,6-dimethylphenylene ether based tandem dicationic ionomer QPPO-DABCO ₂ Preparation of the solution

3g of BPPO (-CH) having a bromomethylation degree of 0.20 ₂ Br,4.41 mmol) was dissolved in an appropriate 20mL of NMP, the BPPO content in the reaction mixture was 0.15g/mL, 1-methyl-1,4-diazabicyclo [2,2,2] was added]Octyl ammonium iodide

(1.121g, 4.41mmol) is stirred vigorously at the rotation speed of 150rpm and reacted at normal temperature for 72h to obtain brown viscous poly 2,6-dimethylphenylene ether based tandem dicationic ionomer QPPO-DABCO ₂ The concentration of the solution was 16.70wt%.

Taking poly 2,6-dimethylphenylene ether based tandem dicationic ionomer QPPO-DABCO ₂ 4mL of the solution was poured into the wet CA prepared in step (1) ₁ Let QPPO-DABCO ₂ The solution was cast naturally and then the other piece of CA was cast ₁ Horizontal flip overlay in QPPO-DABCO ₂ Constructing a sandwich structure composite membrane taking a poly 2,6-dimethylphenylene ether based serial dicationic ionomer liquid membrane as a core on the liquid membrane, wherein each square centimeter of CA ₁ Membrane QPPO-DABCO ₂ The dosage of the solution is 0.04mL, the composite membrane is heated at 60 ℃ for 48h to slowly remove volatile components, and the NMP boundary is accelerated by thermal induction in the initial heating stagePlanar dual vertical diffusion of core ionomer QPPO-DABCO ₂ Stepwise dissolution directed implantation of CA ₁ Anti-fouling layer to obtain ionomer and CA ₁ Partially interpenetrating double-sided anti-fouling structure, complete CA along with extension of heating time and NMP volatilization ₁ And curing an ionomer body to obtain a dry film with a stable anti-fouling structure on two sides, and fully soaking the dry film in distilled water to obtain the protein-pollution-resistant high-anion-conduction electrodialysis anion exchange membrane QPPO-DABCO ₂ -CA ₁ 。

Protein contamination resistant high anion conduction electrodialysis anion exchange membrane QPPO-DABCO ₂ -CA ₁ The basic properties of (A): at room temperature, the ion selective permeability is 92.27%, the water contact angle is 58.25 degrees, and the surface resistance is 2.48 omega/cm ² The tensile strength was 18.35MPa, the water absorption was 24.60%, and the swelling ratio was 4.80%.

QPPO-DABCO ₂ -CA ₁ ED desalting performance of salted egg white: current efficiency η =80.48% (10 mA/cm) ² )；QPPO-DABCO ₂ Salted egg white ED desalting performance: current efficiency η =74.63 (10 mA/cm) ² ) (ii) a Japanese ASTOM commercial membrane AMX salted egg white ED desalting performance: current efficiency η =78.21%; QPPO-DABCO ₂ -CA ₁ The ED desalting performance of the salted egg white is superior to QPPO-DABCO ₂ Description of QPPO-DABCO ₂ -CA ₁ QPPO-DABCO with resistance to protein contamination ₂ -CA ₁ The ED desalting performance of the salted egg white is superior to that of AMX (amino propyl pyrrolidone) -explained QPPO-DABCO ₁ -CA ₁ Has high anion conductivity.

Example 5

2wt% of SA solution 10mL was uniformly spread in a horizontally placed glass plate holding area of 15 cm. Times.15 cm, and 50mL of 0.10mol/L CaCl ₂ The solution is evenly sprayed on an SA liquid membrane and reacts for 20 minutes at room temperature to form the unidirectional gradient cross-linked anti-fouling calcium sodium alginate hydrogel ultrathin membrane CA ₂ 。

3g of BPPO (-CH) having a bromomethylation degree of 0.20 ₂ Br,4.41 mmol) was dissolved in an appropriate 27mL of NMP, the BPPO content in the reaction mixture was 0.11g/mL, and 1-methyl-1,4-diazabicyclo [2,2,2] was added]Octyl ammonium iodide

(1.121g, 4.41mmol) is stirred vigorously at the rotation speed of 200rpm and reacted at normal temperature for 72h to obtain brown viscous poly 2,6-dimethylphenylene ether based tandem dicationic ionomer QPPO-DABCO ₂ The concentration of the solution was 12.93wt%.

Taking poly 2,6-dimethylphenylene ether based tandem dicationic ionomer QPPO-DABCO ₂ 9mL of the solution was poured into the wet CA prepared in step (1) in parallel ₂ Let QPPO-DABCO ₂ The solution was cast naturally and then the other piece of CA was cast ₂ Horizontal flip overlay in QPPO-DABCO ₂ Constructing a sandwich structure composite membrane taking a poly 2,6-dimethylphenylene ether based serial dicationic ionomer liquid membrane as a core on the liquid membrane, wherein each square centimeter of CA ₂ Membrane QPPO-DABCO ₂ The using amount of the solution is 0.04mL, the composite membrane is heated at 60 ℃ for 48h to slowly remove volatile components, and the interlayer ionomer QPPO-DABCO is subjected to bidirectional vertical diffusion at the NMP interface through thermal induction acceleration in the initial heating stage ₂ Stepwise dissolution directed implantation of CA ₂ Anti-fouling layer to obtain ionomer and CA ₂ Partially interpenetrating double-sided anti-fouling structure, complete CA along with extension of heating time and NMP volatilization ₂ And curing with an ionomer body to obtain a dry film with a stable anti-fouling structure on two sides, and fully soaking the dry film in distilled water to obtain the protein-pollution-resistant high anion-conduction electrodialysis anion exchange membrane QPPO-DABCO ₂ -CA ₂ 。

Protein contamination resistant high anion conduction electrodialysis anion exchange membrane QPPO-DABCO ₂ -CA ₂ The basic properties of (A): at room temperature, the ion selective permeability is 92.31%, the water contact angle is 54.80 degrees, and the surface resistance is 2.31 omega/cm ² The tensile strength is 15.80MPa, the water absorption is 22.60 percent, and the swelling ratio is 10.33 percent.

QPPO-DABCO ₂ -CA ₂ ED desalting performance of salted egg white: current efficiency η =83.82% (10 mA/cm) ² )；QPPO-DABCO ₂ Salted egg white ED desalting performance: current efficiency η =74.63 (10 mA/cm) ² ) (ii) a Commercial membrane AMX salted egg white ED desalting performance of ASTOM japan: current efficiency η =78.21%; QPPO-DABCO ₂ -CA ₂ The ED desalting performance of the salted egg white is superior to QPPO-DABCO ₂ Description of QPPO-DABCO ₂ -CA ₂ QPPO-DABCO with resistance to protein contamination ₂ -CA ₂ The ED desalting performance of the salted egg white is superior to that of AMX (amino propyl pyrrolidone) -explained QPPO-DABCO ₂ -CA ₂ Has high anion conductivity.

Example 6

20mL of SA solution was uniformly spread in a fixed area of 20cm X20 cm of a horizontally placed glass plate, and 100mL of 0.05mol/L CaCl was added ₂ The solution is evenly sprayed on an SA liquid film and reacts for 20 minutes at room temperature to form the unidirectional gradient cross-linked antifouling calcium sodium alginate hydrogel ultrathin film CA ₃ 。

3g BPPO (-CH) with a bromomethylation degree of 0.20 ₂ Br,4.41 mmol) was dissolved in an appropriate 30mL of NMP, the BPPO content in the reaction mixture was 0.10g/mL, and 1-methyl-1,4-diazabicyclo [2,2,2] was added]Octyl ammonium iodide

(1.121g, 4.41mmol) is stirred vigorously at the rotation speed of 150rpm and reacted for 72h at normal temperature to obtain brown viscous poly 2,6-dimethylphenylene ether based serial dicationic ionomer QPPO-DABCO ₂ The solution had a concentration of 11.79wt%.

Taking poly 2,6-dimethylphenylene ether based tandem dicationic ionomer QPPO-DABCO ₂ 16mL of the solution was poured into the wet CA prepared in step (1) in parallel ₃ Let QPPO-DABCO ₂ The solution was cast naturally and then the other piece of CA was cast ₃ Horizontal flip overlay in QPPO-DABCO ₂ Constructing a sandwich structure composite membrane taking a poly 2,6-dimethylphenylene ether based serial dicationic ionomer liquid membrane as a core on the liquid membrane, wherein each square centimeter of CA ₃ Membrane QPPO-DABCO ₂ The using amount of the solution is 0.04mL, the composite membrane is heated at 60 ℃ for 48h to slowly remove volatile components, and the interlayer ionomer QPPO-DABCO is subjected to bidirectional vertical diffusion at the NMP interface through thermal induction in the initial heating stage ₂ Stepwise dissolution directed implantation of CA ₃ Anti-fouling layer to obtain ionomer and CA ₃ Partially interpenetrating double-sided anti-fouling structure, complete CA along with extension of heating time and NMP volatilization ₃ And curing with an ionomer body to obtain a dry film with a stable anti-fouling structure on two sides, and fully soaking the dry film in distilled water to obtain the protein-pollution-resistant high anion-conduction electrodialysis anion exchange membrane QPPO-DABCO ₂ -CA ₃ 。

Protein contamination resistant high anion conduction electrodialysis anion exchange membrane QPPO-DABCO ₂ -CA ₃ The basic properties of (A): at room temperature, the ion permselectivity was 92.83%, the water contact angle was 58.25 °, and the sheet resistance was 2.47. Omega./cm ² The tensile strength was 17.35MPa, the water absorption was 22.46% and the swelling ratio was 5.80%.

QPPO-DABCO ₂ -CA ₃ ED desalting performance of salted egg white: current efficiency η =82.10% (10 mA/cm) ² )；QPPO-DABCO ₂ Salted egg white ED desalting performance: current efficiency η =74.63 (10 mA/cm) ² ) (ii) a Japanese ASTOM commercial membrane AMX salted egg white ED desalting performance: current efficiency η =78.21%; QPPO-DABCO ₂ -CA ₁ The ED desalting performance of the salted egg white is superior to QPPO-DABCO ₂ Description of QPPO-DABCO ₂ -CA ₃ QPPO-DABCO with resistance to protein contamination ₂ -CA ₃ ED desalting performance of the salted egg white is superior to AMX explanation QPPO-DABCO ₂ -CA ₃ Has high anion conductivity.

It should be noted that the protection scope of the present invention is not limited by the above-mentioned embodiments, and any equivalent changes, modifications or evolutions made by those skilled in the art using the technical solution of the present invention are still within the protection scope of the technical solution of the present invention.

Claims

1. The preparation method of the protein pollution resistant high anion conduction electrodialysis anion exchange membrane is characterized by comprising the following steps:

1) Uniformly spreading a sodium alginate solution on a glass plate, uniformly spraying a calcium chloride solution on the sodium alginate solution, and reacting at room temperature to form the anti-fouling calcium alginate sodium hydrogel ultrathin film with unidirectional gradient crosslinking;

2) Dissolving brominated poly 2,6-dimethylphenylene ether in N-methylpyrrolidone, adding 1,4-diazabicyclo [2,2,2] octane monocationic derivative, stirring, and reacting at normal temperature for 48-72 h to obtain a viscous poly 2,6-dimethylphenylene ether-based tandem dicationic ionomer solution;

2. The method for preparing a protein contamination resistant high anion conduction electrodialysis anion exchange membrane according to claim 1, wherein in the step (1), the concentration of the sodium alginate solution is 1-2 wt%; the solution concentration of the calcium chloride solution is 0.05 mol/L-0.10 mol/L.

3. The method for preparing a protein contamination resistant high anion conduction electrodialysis anion exchange membrane according to claim 1, wherein in the step (1), the amount of the sodium alginate solution on each square centimeter of the antifouling calcium sodium alginate hydrogel ultrathin membrane is 0.04 mL-0.05 mL, and the volume ratio of the calcium chloride solution to the sodium alginate solution is 4-6:1.

4. the method for preparing a protein contamination resistant high anion conduction electrodialysis anion exchange membrane according to claim 1, wherein the reaction time at room temperature in step (1) is 15-25 minutes.

5. The method for preparing a protein contamination resistant high anion conduction electrodialysis anion exchange membrane according to claim 1, wherein in the step (2), the bromomethylation degree of the brominated poly 2,6-dimethylphenylene oxide is 0.2-0.4; after the brominated poly (2,6-dimethylphenylene oxide) is dissolved in N-methyl pyrrolidone, the solid content of the brominated poly (2,6-dimethylphenylene oxide) is 0.10 g/mL-0.15 g/mL.

6. The method for preparing a high anion conduction electrodialysis anion exchange membrane for resisting protein contamination according to claim 1, wherein, in the step (2), the molar ratio of bromomethyl of brominated poly 2,6-dimethylphenylene ether, 1,4-diazabicyclo [2,2,2] octane monocationic derivative is 1:1, the rotating speed of the stirring is 100 rpm-200 rpm; the concentration of the poly 2,6-dimethylphenylene ether based tandem dication ionomer solution is 11.8wt% -16.7 wt%.

7. The method for preparing a protein contamination resistant high anion conduction electrodialysis anion exchange membrane according to claim 1, wherein in step (2), 1,4-diazabicyclo [2,2,2]The octane radical monocationic derivative is 1-hexyl-1,4-diazabicyclo [2,2,2]Octyl ammonium bromide

Or 1-methyl-1,4-diazabicyclo [2,2,2]Octyl ammonium iodide

8. The method for preparing a protein contamination resistant high anion conduction electrodialysis anion-exchange membrane according to claim 1, wherein in step (3), 0.04-0.05mL of the solution of poly 2,6-dimethylphenylene ether based serial dicationic ionomer is coated on each square centimeter of the antifouling calcium sodium alginate hydrogel ultrathin membrane; the volatile component removal is realized by heating for 40-48h at 60-65 ℃.

9. A high anion conduction electrodialysis anion exchange membrane resistant to protein contamination, characterized in that it is produced by the production method of any one of claims 1 to 8; at room temperature, the ion permselectivity of the high anion-conduction electrodialysis anion exchange membrane is 90-93%, the water contact angle is 54-59 degrees, and the surface resistance is 2.1 omega/cm ² ～2.6Ω/cm ² The tensile strength is 14.5MPa to 20.4MPa, the water absorption rate is 18.6 percent to 24.6 percent, and the swelling rate is 4.2 percent to 10.4 percent.

10. Use of the protein contamination resistant high anion conduction electrodialysis anion exchange membrane of claim 9 in electrodialysis desalination of a protein system.