Preparation method of sericin-assisted polymerized high-flux nanofiltration membrane
By adding sericin and polyaromatic acid chloride to the interfacial polymerization process of the nanofiltration membrane, the growth and cross-linking of polyamides are controlled, and the existing nanofiltration membranes are solved, and the filtration efficiency and stability are achieved.
Patent Information
- Application Number
- CN202510182800.8
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-02-19
- Publication Date
- 2025-04-11
AI Technical Summary
During the interfacial polymerization process of existing nanofiltration membranes, monomer diffusion and polymer growth are uneven, resulting in high density and low permeability of the polyamide layer, thereby reducing the filtration efficiency.
By adding sericin to the aqueous solution, the polar groups are used to form hydrogen bonds with the aqueous amine monomer, the diffusion and interface reaction of the amine monomer is controlled, the uniform growth of polyamide is promoted, and the cross-linked structure is formed through the polyaromatic acid chloride in the oil-phase solution, and the stability of the film is improved.
The permeability flux and desalting performance of the nanofiltration membrane are improved, the stability of the polyamide network is enhanced, and the filtration efficiency is reduced due to local density is avoided.
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Figure CN119793234A_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to the technical field of nanofiltration membrane separation, and in particular to a method for preparing a high-throughput nanofiltration membrane by sericin-assisted polymerization. Background Art
[0002] Membrane separation technology plays an important role in the development of modern production. Due to its advantages in high separation efficiency, low energy consumption, and high separation accuracy, it has been widely used in various fields such as food, biomedicine, and semiconductors. In these membrane separation processes, the filtration accuracy of nanofiltration is about one nanometer. It has broad application prospects in liquid separation systems such as organic desalination, small molecule organic purification, and multivalent inorganic salt separation, and has been increasingly introduced into these processes.
[0003] The separation performance of nanofiltration is greatly affected by the membrane material and structural characteristics. The most common commercial nanofiltration membrane is made by using polyamines and acyl chlorides to form a polyamide separation layer on a porous substrate through interfacial polymerization. However, due to the rapid diffusion of monomers and growth of polymers in the interface area, the microstructure of polyamide is difficult to accurately control to achieve accurate separation of the target substance. In addition, the uneven diffusion and growth will cause the polyamide to be locally too dense, reducing the permeability of the nanofiltration membrane and thereby reducing the filtration efficiency of nanofiltration separation. Summary of the invention
[0004] The object of the present invention is to provide a method for preparing a high-throughput nanofiltration membrane by sericin-assisted polymerization, so as to solve the problem of how to control the uniform growth of polyamide by regulating the diffusion and reaction of monomer molecules.
[0005] To achieve the above object, the present invention provides the following technical solution: a method for preparing a high-throughput nanofiltration membrane assisted by sericin polymerization, comprising the following steps:
[0006] S1. preparing an aqueous phase solution: adding sericin and piperazine into deionized water, and stirring the sericin and piperazine until they are completely dissolved to form an aqueous phase solution;
[0007] S2. preparing an oil phase solution: adding a polybasic aromatic acyl chloride to an alkane organic solvent Isopar G and stirring until it is completely dissolved to form an oil phase solution;
[0008] S3, soaking the polysulfone ultrafiltration membrane in the aqueous solution: placing the polysulfone ultrafiltration membrane in the aqueous solution, taking it out after soaking for a period of time, using a rubber roller to remove excess solution on the membrane surface, and purging it with nitrogen;
[0009] S4, soaking the polysulfone ultrafiltration membrane in the oil phase solution: placing the polysulfone ultrafiltration membrane soaked in the water phase and cleaned in the prepared oil phase solution, soaking it again for a period of time and then taking it out;
[0010] S5. Heat treatment: heat-treating the polysulfone ultrafiltration membrane soaked in the oil phase to obtain a high-flux nanofiltration membrane.
[0011] Preferably, in said S1, when adding sericin and piperazine to deionized water for stirring, the stirring needs to be carried out in a water bath at a temperature of 20°C to 60°C. In said S1, the molecular weight distribution of sericin is between 50k and 200k Daltons.
[0012] Preferably, in the S1 aqueous solution, the mass concentration of sericin is in the range of 0.1% to 1% based on the total mass of the aqueous solution, and the mass concentration of piperazine in the S1 aqueous solution is in the range of 0.8% to 1.2%.
[0013] Preferably, in the S2, the aromatic acyl chloride is one or more of trimesoyl chloride, isophthaloyl chloride, benzenesulfonyl chloride and p-toluenesulfonyl chloride, and in the S2 oil phase solution, the total mass concentration of the aromatic acyl chloride is in the range of 0.01% to 0.2% based on the total mass of the oil phase solution.
[0014] Preferably, in S3, the polysulfone ultrafiltration membrane needs to be immersed in the aqueous solution for 3 min to 5 min, and the molecular weight cutoff of the polysulfone ultrafiltration membrane is between 20k and 30k Daltons.
[0015] Preferably, the polysulfone ultrafiltration membrane needs to be hydrophilically modified before being soaked in the aqueous solution. The polysulfone ultrafiltration membrane needs to be soaked in a hydrophilic agent aqueous solution, left to stand for a period of time, and then taken out to dry.
[0016] Preferably, the hydrophilic agent aqueous solution contains one or more of sodium tripolyphosphate, sodium bicarbonate, sodium dodecyl sulfate and hexadecyltrimethylammonium bromide, and the total mass concentration of the hydrophilic agent is in the range of 0.1% to 1% based on the total mass of the hydrophilic agent aqueous solution.
[0017] Preferably, in S5, the polysulfone ultrafiltration membrane soaked in the oil phase solution needs to be placed in a forced air drying oven for heat treatment.
[0018] Preferably, in S5, heat treatment is required at 20°C to 80°C, and the membrane is taken out after curing for 2min to 10min, and then immersed in deionized water for 12h to obtain a high-flux nanofiltration membrane.
[0019] Compared with the prior art, the present invention has the following beneficial effects:
[0020] The present invention adds sericin to the aqueous solution. Since its molecules contain a large number of polar groups such as amino and carboxyl groups, they can generate strong hydrogen bonds with aqueous amine monomers, control the diffusion and interfacial reaction of amine monomers during interfacial polymerization, and alleviate the problem of local over-density of the polyamide layer, thereby improving the permeation flux. At the same time, sericin molecules contain a large number of molecular chains such as serine, aspartic acid, and glycine, which can form an interpenetrating structure with the polyamide network. Such mutual entanglement can enhance the stability of the polyamide network and prevent the problem of excessive looseness of the polyamide caused by excessive inhibition of the amine monomer, thereby ensuring the desalination performance of the polyamide. BRIEF DESCRIPTION OF THE DRAWINGS
[0021] Figure 1 The present invention provides a flow chart of a preferred embodiment of the method for preparing a high-throughput nanofiltration membrane assisted by sericin polymerization. DETAILED DESCRIPTION
[0022] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.
[0023] See also Figure 1 As shown, a method for preparing a high-throughput nanofiltration membrane assisted by sericin polymerization comprises the following steps:
[0024] S1. preparing an aqueous phase solution: adding sericin and piperazine into deionized water, and stirring the sericin and piperazine until they are completely dissolved to form an aqueous phase solution;
[0025] S2. preparing an oil phase solution: adding a polybasic aromatic acyl chloride to an alkane organic solvent Isopar G and stirring until it is completely dissolved to form an oil phase solution;
[0026] S3, soaking the polysulfone ultrafiltration membrane in the aqueous solution: placing the polysulfone ultrafiltration membrane in the aqueous solution, taking it out after soaking for a period of time, using a rubber roller to remove excess solution on the membrane surface, and purging it with nitrogen;
[0027] S4, soaking the polysulfone ultrafiltration membrane in the oil phase solution: placing the polysulfone ultrafiltration membrane soaked in the water phase and cleaned in the prepared oil phase solution, soaking it again for a period of time and then taking it out;
[0028] S5. Heat treatment: heat-treating the polysulfone ultrafiltration membrane soaked in oil phase to obtain a high-flux nanofiltration membrane.
[0029] In S1, when sericin and piperazine are added to deionized water and stirred, the stirring needs to be carried out in a water bath at a temperature of 20°C to 60°C. In S1, the molecular weight distribution of sericin is between 50k and 200k Daltons.
[0030] In the S1 aqueous solution, the mass concentration of sericin is in the range of 0.1% to 1% based on the total mass of the aqueous solution. In the S1 aqueous solution, the mass concentration of piperazine is in the range of 0.8% to 1.2%.
[0031] In S2, the aromatic acyl chloride is one or more of trimesoyl chloride, isophthaloyl chloride, benzenesulfonyl chloride and p-toluenesulfonyl chloride. In the S2 oil phase solution, the total mass concentration of the aromatic acyl chloride is in the range of 0.01% to 0.2% based on the total mass of the oil phase solution.
[0032] In S3, the polysulfone ultrafiltration membrane needs to be immersed in the aqueous solution for 3 minutes to 5 minutes, and the molecular weight cutoff of the polysulfone ultrafiltration membrane is between 20k and 30k Daltons.
[0033] The polysulfone ultrafiltration membrane needs to be hydrophilically modified before being soaked in an aqueous solution. The polysulfone ultrafiltration membrane needs to be soaked in a hydrophilic agent aqueous solution, left to stand for a period of time, and then taken out to dry.
[0034] The hydrophilic agent aqueous solution contains one or more of sodium tripolyphosphate, sodium bicarbonate, sodium dodecyl sulfonate and hexadecyl trimethyl ammonium bromide. The total mass concentration of the hydrophilic agent is between 0.1% and 1% based on the total mass of the hydrophilic agent aqueous solution.
[0035] refer to Figure 1 As shown, in S5, the polysulfone ultrafiltration membrane soaked with the oil phase solution needs to be placed in a forced air drying oven for heat treatment.
[0036] In S5, heat treatment is required at 20°C to 80°C, and after curing for 2min to 10min, the membrane is taken out and then immersed in deionized water for 12h to obtain a high-flux nanofiltration membrane.
[0037] Embodiment 1
[0038] Weigh 0.2g of sericin and 1g of piperazine, add them to 98.8g of deionized water, heat and stir in a water bath at 30°C for 30min until completely dissolved to form an aqueous phase solution; weigh 0.05g of trimesoyl chloride, add it to 99.95g of organic solvent IsoparG, heat and stir in a water bath at 45°C for 1h to form an oil phase solution; weigh 0.5g of sodium tripolyphosphate and 0.1g of sodium dodecyl sulfate, add them to 99.4g of deionized water, stir in a water bath at 30°C for 30min until completely dissolved to form a hydrophilic agent; k Dalton polysulfone ultrafiltration membrane was immersed in a hydrophilic agent, taken out after 5 minutes, and the excess solution on the membrane surface was removed with a rubber roller, and then dried in a natural state for 2 minutes. The above hydrophilically modified and dried polysulfone ultrafiltration membrane was immersed in an aqueous phase solution, taken out after 5 minutes, and the excess solution on the membrane surface was removed with a rubber roller. The membrane surface was purged with nitrogen to make it free of obvious droplets; it was then immersed in an oil phase solution, taken out after 60 seconds, transferred to a forced air drying oven, heat treated at 50°C for 5 minutes, taken out, and immersed in deionized water for 12 hours to obtain a nanofiltration membrane.
[0039] Embodiment 2
[0040] Weigh 0.4g of sericin and 1g of piperazine, add them to 98.6g of deionized water, heat and stir in a water bath at 30°C for 30min until completely dissolved to form an aqueous phase solution; weigh 0.05g of trimesoyl chloride, add it to 99.95g of organic solvent IsoparG, heat and stir in a water bath at 45°C for 1h to form an oil phase solution; weigh 0.5g of sodium tripolyphosphate and 0.1g of sodium dodecyl sulfate, add them to 99.4g of deionized water, stir in a water bath at 30°C for 30min until completely dissolved to form a hydrophilic agent; k Dalton polysulfone ultrafiltration membrane was immersed in a hydrophilic agent, taken out after 5 minutes, and the excess solution on the membrane surface was removed with a rubber roller, and then dried in a natural state for 2 minutes. The above hydrophilically modified and dried polysulfone ultrafiltration membrane was immersed in an aqueous phase solution, taken out after 5 minutes, and the excess solution on the membrane surface was removed with a rubber roller. The membrane surface was purged with nitrogen to make it free of obvious droplets; it was then immersed in an oil phase solution, taken out after 60 seconds, transferred to a forced air drying oven, heat treated at 50°C for 5 minutes, taken out, and immersed in deionized water for 12 hours to obtain a nanofiltration membrane.
[0041] Embodiment 3
[0042] Weigh 0.4g of sericin and 1.2g of piperazine, add them to 98.4g of deionized water, heat and stir in a water bath at 30℃ for 30min until completely dissolved to form an aqueous phase solution; weigh 0.05g of trimesoyl chloride, add it to 99.95g of organic solvent IsoparG, heat and stir in a water bath at 45℃ for 1h to form an oil phase solution; weigh 0.5g of sodium tripolyphosphate and 0.1g of sodium dodecyl sulfate, add them to 99.4g of deionized water, stir in a water bath at 30℃ for 30min until completely dissolved to form a hydrophilic agent; A 5kDalton polysulfone ultrafiltration membrane was immersed in a hydrophilic agent and taken out after 5 minutes. The excess solution on the membrane surface was removed with a rubber roller and then air-dried for 2 minutes in a natural state. The hydrophilically modified and air-dried polysulfone ultrafiltration membrane was immersed in an aqueous solution and taken out after 5 minutes. The excess solution on the membrane surface was removed with a rubber roller and the membrane surface was purged with nitrogen to remove obvious droplets. The membrane was then immersed in an oil solution and taken out after 60 seconds. The membrane was transferred to a forced air drying oven, heat treated at 50°C for 5 minutes, taken out, and immersed in deionized water for 12 hours to obtain a nanofiltration membrane.
[0043] Embodiment 4
[0044] Weigh 0.2g of sericin and 1g of piperazine, add them to 98.8g of deionized water, heat and stir in a water bath at 30°C for 30min until completely dissolved to form an aqueous phase solution; weigh 0.1g of trimesoyl chloride and 0.05g of benzenesulfonyl chloride, add them to 99.85g of organic solvent IsoparG, heat and stir in a water bath at 45°C for 1h to form an oil phase solution; weigh 0.5g of sodium tripolyphosphate and 0.1g of sodium dodecyl sulfate, add them to 99.4g of deionized water, stir in a water bath at 30°C for 30min until completely dissolved to form a hydrophilic agent; A polysulfone ultrafiltration membrane with a mass of 25 kDa was immersed in a hydrophilic agent, taken out after 5 minutes, and the excess solution on the membrane surface was removed with a rubber roller, and then dried in a natural state for 2 minutes. The above hydrophilically modified and dried polysulfone ultrafiltration membrane was immersed in an aqueous solution, taken out after 5 minutes, and the excess solution on the membrane surface was removed with a rubber roller. The membrane surface was purged with nitrogen to make it free of obvious droplets; it was then immersed in an oil solution, taken out after 60 seconds, transferred to a forced drying oven, heat treated at 50°C for 5 minutes, taken out, and immersed in deionized water for 12 hours to obtain a nanofiltration membrane.
[0045] Embodiment 5
[0046] Weigh 0.2g of sericin and 1g of piperazine, add them to 98.8g of deionized water, heat and stir in a water bath at 30°C for 30min until completely dissolved to form an aqueous phase solution; weigh 0.1g of trimesoyl chloride and 0.05g of benzenesulfonyl chloride, add them to 99.85g of organic solvent IsoparG, heat and stir in a water bath at 45°C for 1h to form an oil phase solution; weigh 0.5g of sodium tripolyphosphate and 0.2g of sodium dodecyl sulfate, add them to 99.3g of deionized water, stir in a water bath at 30°C for 30min until completely dissolved to form a hydrophilic agent; A polysulfone ultrafiltration membrane with a mass of 25 kDa was immersed in a hydrophilic agent, taken out after 5 minutes, and the excess solution on the membrane surface was removed with a rubber roller, and then dried in a natural state for 2 minutes. The above hydrophilically modified and dried polysulfone ultrafiltration membrane was immersed in an aqueous solution, taken out after 5 minutes, and the excess solution on the membrane surface was removed with a rubber roller. The membrane surface was purged with nitrogen to make it free of obvious droplets; it was then immersed in an oil solution, taken out after 60 seconds, transferred to a forced drying oven, heat treated at 50°C for 5 minutes, taken out, and immersed in deionized water for 12 hours to obtain a nanofiltration membrane.
[0047] Comparative Example 1
[0048] Weigh 1g piperazine, add it to 99g deionized water, heat and stir in a water bath at 30℃ for 30min until it is completely dissolved to form an aqueous phase solution; weigh 0.05g trimesoyl chloride, add it to 99.95g organic solvent IsoparG, heat and stir in a water bath at 45℃ for 1h to form an oil phase solution; weigh 0.5g sodium tripolyphosphate and 0.2g sodium dodecyl sulfate, add them to 99.3g deionized water, stir in a water bath at 30℃ for 30min until it is completely dissolved to form a hydrophilic agent; add a poly (vinyl alcohol) with a molecular weight cutoff of 25k Daltons The sulfone ultrafiltration membrane was immersed in a hydrophilic agent and taken out after 5 minutes. The excess solution on the membrane surface was removed with a rubber roller and then dried in a natural state for 2 minutes. The hydrophilically modified and dried polysulfone ultrafiltration membrane was immersed in an aqueous solution and taken out after 5 minutes. The excess solution on the membrane surface was removed with a rubber roller and the membrane surface was purged with nitrogen to make it free of obvious droplets. It was then immersed in an oil solution and taken out after 60 seconds. It was transferred to a forced drying oven, taken out after heat treatment at 50°C for 5 minutes, and immersed in deionized water for 12 hours to obtain a nanofiltration membrane.
[0049] Comparative Example 2
[0050] Weigh 0.2g of sericin and 1g of piperazine, add them to 98.8g of deionized water, heat and stir in a water bath at 30°C for 30min until completely dissolved to form an aqueous solution; weigh 0.05g of trimesoyl chloride, add it to 99.95g of organic solvent IsoparG, heat and stir in a water bath at 45°C for 1h to form an oil solution; soak a polysulfone ultrafiltration membrane with a molecular weight cutoff of 25k Daltons in the aqueous solution, take it out after 5min, remove excess solution on the membrane surface with a rubber roller, and blow nitrogen gas on the membrane surface to make it free of obvious droplets; then soak it in the oil solution, take it out after 60s, transfer it to a forced drying oven, heat treat it at 50°C for 5min, take it out, and soak it in deionized water for 12h to obtain a nanofiltration membrane.
[0051] The nanofiltration membranes prepared in the above specific examples 1, 2, 3, 4, 5, 6 and 7 were tested for performance. The membranes were fixed in a conventional cross-flow filtration test pool with an effective filtration area of 19.2 cm 2 , the filtration system temperature was controlled at 25°C, the operating pressure was 0.4MPa, and the inorganic salt concentration used was 2000ppm;
[0052] The test results are shown in the following table:
[0053]
[0054] Combining the test results of Example 1, Example 2, Example 3 and Comparative Example 1, it can be seen that the introduction of sericin into the water phase effectively improves the desalination rate and water flux of the nanofiltration membrane, and the improvement of membrane performance can be controlled by adjusting the concentration of sericin.
[0055] Combining the test results of Example 1, Example 4 and Example 5, it can be seen that on the basis of introducing sericin into the interfacial polymerization process, benzenesulfonyl chloride added to the oil phase can also further improve the salt rejection rate and water flux of the nanofiltration membrane;
[0056] Combining the test results of Example 1 and Comparative Example 2, it can be seen that the polysulfone ultrafiltration membrane modified by the hydrophilic agent can better play the role of sericin in improving the performance of the nanofiltration membrane;
[0057] In summary, in the process of preparing nanofiltration membrane, the desalination rate and water flux of the nanofiltration membrane can be improved by introducing sericin, and on the basis of introducing sericin, adding benzenesulfonyl chloride to the oil phase can further improve the desalination rate and water flux of the nanofiltration membrane. At the same time, the polysulfone ultrafiltration membrane modified by a hydrophilic agent can improve the effect of sericin on improving the performance of the nanofiltration membrane.
[0058] Working principle: When preparing the high-flux nanofiltration membrane, the staff first added sericin and piperazine to ionized water, wherein the molecular weight of sericin was between 50k and 200k Daltons, and stirred them in a water bath at 20°C to 60°C until the two were completely dissolved to form a uniform aqueous solution. At this time, the concentrations of sericin and piperazine were controlled between 0.1% to 1% and 0.8% to 1.2%, respectively, to ensure the effect of the subsequent reaction, and then complete the preparation of the aqueous solution. Then, the oil phase solution was prepared. The staff first added polybasic aromatic acyl chlorides to the alkane organic solvent IsoparG, wherein the polybasic aromatic acyl chlorides can be selected from one or more of trimesoyl chloride, isophthaloyl chloride, benzenesulfonyl chloride and p-toluenesulfonyl chloride, and then heated and stirred in a water bath at 30°C to 50°C until they were completely dissolved to form an oil phase solution, and the concentration of the aromatic acyl chlorides was controlled at 0.01% to 0.2% of the total mass of the oil phase solution. Then the staff placed the hydrophilically modified polysulfone ultrafiltration membrane in an aqueous solution, wherein the polysulfone ultrafiltration membrane had a molecular weight cutoff of 20k to 30k Daltons, soaked for 3 to 5 minutes before taking it out, then used a rubber roller to remove excess solution on the membrane surface, and purged it with nitrogen to ensure the uniformity and cleanliness of the membrane surface. After the soaking was completed, the polysulfone ultrafiltration membrane that had been soaked in the aqueous phase and cleaned was placed in the prepared oil phase solution, soaked again for a period of time and then taken out, the soaking time was 10S to 120s, so that the membrane surface reacted with the polyvalent aromatic acyl chloride in the oil phase solution to form a cross-linked structure, and then the staff placed the polysulfone ultrafiltration membrane soaked in the oil phase in a blast drying oven for heat treatment, cured at a temperature of 20°C to 80°C for 2 to 10 minutes before taking it out, and then soaked it in deionized water for 12 hours to remove unreacted chemicals and solvents, and at the same time make the membrane structure more stable, thereby obtaining a high-flux nanofiltration membrane.
[0059] It should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, the elements defined by the sentence "comprise a ..." do not exclude the existence of other identical elements in the process, method, article or device including the elements.
[0060] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.
Claims
1. A method for preparing a high-throughput nanofiltration membrane assisted by sericin polymerization, characterized in that: The following steps are involved: S1. preparing an aqueous phase solution: adding sericin and piperazine into deionized water, and stirring the sericin and piperazine until they are completely dissolved to form an aqueous phase solution; S2. preparing an oil phase solution: adding a polybasic aromatic acyl chloride to an alkane organic solvent Isopar G and stirring until it is completely dissolved to form an oil phase solution; S3, soaking the polysulfone ultrafiltration membrane in the aqueous solution: placing the polysulfone ultrafiltration membrane in the aqueous solution, taking it out after soaking for a period of time, using a rubber roller to remove excess solution on the membrane surface, and purging it with nitrogen; S4, soaking the polysulfone ultrafiltration membrane in the oil phase solution: placing the polysulfone ultrafiltration membrane soaked in the water phase and cleaned in the prepared oil phase solution, soaking it again for a period of time and then taking it out; S5. Heat treatment: heat-treating the polysulfone ultrafiltration membrane soaked in the oil phase to obtain a high-flux nanofiltration membrane.
2. The method for preparing a high-throughput nanofiltration membrane by sericin-assisted polymerization according to claim 1, characterized in that: In the above S1, when the sericin and piperazine are added to the deionized water and stirred, the stirring needs to be carried out in a water bath at a temperature of 20°C to 60°C. In the above S1, the molecular weight distribution of the sericin is between 50k and 200k Daltons.
3. The method for preparing a high-throughput nanofiltration membrane by sericin-assisted polymerization according to claim 1, characterized in that: In the S1 aqueous solution, the mass concentration of sericin is in the range of 0.1% to 1% based on the total mass of the aqueous solution. In the S1 aqueous solution, the mass concentration of piperazine is in the range of 0.8% to 1.2%.
4. The method for preparing a high-throughput nanofiltration membrane by sericin-assisted polymerization according to claim 1, characterized in that: In the S2, the aromatic acyl chloride is one or more of trimesoyl chloride, isophthaloyl chloride, benzenesulfonyl chloride and p-toluenesulfonyl chloride. In the S2 oil phase solution, the total mass concentration of the aromatic acyl chloride is in the range of 0.01% to 0.2% based on the total mass of the oil phase solution.
5. The method for preparing a high-throughput nanofiltration membrane by sericin-assisted polymerization according to claim 1, characterized in that: In S3, the polysulfone ultrafiltration membrane needs to be immersed in the aqueous solution for 3 minutes to 5 minutes, and the molecular weight cutoff of the polysulfone ultrafiltration membrane is between 20k and 30k Daltons.
6. The method for preparing a high-throughput nanofiltration membrane by sericin-assisted polymerization according to claim 1, characterized in that: The polysulfone ultrafiltration membrane needs to be hydrophilically modified before being soaked in an aqueous solution. The polysulfone ultrafiltration membrane needs to be soaked in a hydrophilic agent aqueous solution, left to stand for a period of time, and then taken out and dried.
7. The method for preparing a high-throughput nanofiltration membrane by sericin-assisted polymerization according to claim 6, characterized in that: The hydrophilic agent aqueous solution contains one or more of sodium tripolyphosphate, sodium bicarbonate, sodium dodecyl sulfate and hexadecyltrimethylammonium bromide. The total mass concentration of the hydrophilic agent is in the range of 0.1% to 1% based on the total mass of the hydrophilic agent aqueous solution.
8. The method for preparing a high-throughput nanofiltration membrane by sericin-assisted polymerization according to claim 1, characterized in that: In S5, the polysulfone ultrafiltration membrane soaked in the oil phase solution needs to be placed in a forced air drying oven for heat treatment.
9. The method for preparing a high-throughput nanofiltration membrane by sericin-assisted polymerization according to claim 1, characterized in that: In the S5, it is necessary to perform heat treatment at 20°C to 80°C, take it out after curing for 2min to 10min, and then soak it in deionized water for 12h to obtain a high-flux nanofiltration membrane.