Hesperidin-regulated polyamide nanofiltration membrane as well as preparation method and application thereof

Abstract

The invention discloses a preparation method of a hesperidin regulated polyamide nanofiltration membrane. The preparation method comprises the following steps: S1, contacting the surface of a base membrane with a water-phase solution, standing, and removing the water-phase solution; s2, the surface of the base membrane with the water phase solution removed in the step S1 makes contact with an organic phase solution, interfacial polymerization is carried out, and the hesperidin-regulated polyamide nanofiltration membrane is prepared; the aqueous phase solution contains hesperidin, an amine monomer and water; the mass volume ratio of the hesperidin to the water is (5-10): 1g / L, and the mass volume ratio of the amine monomer to the water is (4-6): 1g / L; the organic phase solution contains an acyl chloride monomer and an organic solvent; the mass volume ratio of the acyl chloride monomer to the organic solvent is (1.3-2): 1g / L. The polyamide nanofiltration membrane has excellent inorganic salt / antibiotic selectivity while keeping excellent water flux and antibiotic rejection rate, and can be applied to devices such as sewage treatment equipment, seawater desalination equipment, industrial wastewater treatment and recycling equipment and the like.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of wastewater and sewage treatment, and more particularly relates to a hesperidin-regulated polyamide nanofiltration membrane, a preparation method therefor and an application thereof. BACKGROUND

[0002] Rational utilization and protection of water resources is an important and arduous task. Wastewater and sewage treatment and resource utilization are key measures to solve the crisis of freshwater resources in China. As a typical pressure-driven membrane separation technology, nanofiltration (NF) has attracted much attention in the field of antibiotic desalination in recent years due to its ability to effectively separate divalent and multivalent ions and organic molecules with a molecular weight of 200-1000 daltons (Da). Currently, the nanofiltration membranes on the market are mainly of thin layer composite (TFC) structure, that is, water-phase amine monomers and organic-phase acyl chloride monomers are generated into polyamide nanofiltration membranes on the surface of ultrafiltration or microfiltration base membranes through an interfacial polymerization process.

[0003] Currently, the preparation of antibiotics is mainly carried out by fermentation process for mass production, which includes the following main steps: seed fermentation, fermentation broth pretreatment, plate and frame filtration, exchange resin adsorption, exchange resin elution, desalination, crystallization, drying and the like. In order to ensure the stability of the fermentation broth system during the fermentation process, a certain amount of inorganic salt is usually added to the fermentation broth, and therefore, it is necessary to separate the wastewater containing antibiotics and salt after the fermentation is completed.

[0004] Membrane separation is a newly emerging antibiotic desalination technology in recent years, which has the characteristics of efficient and continuous process, simple equipment and no use of organic solvents in the process. However, due to the strong reactivity of traditional monomers, the interfacial polymerization (IP) process is fast and difficult to control, resulting in a very dense and thick polyamide nanofiltration membrane. This not only leads to a high rejection rate of the polyamide nanofiltration membrane to antibiotics and inorganic salts (i.e. low salt / antibiotic separation efficiency), but also results in a low water flux, which seriously limits the application of polyamide nanofiltration membranes in the field of antibiotic desalination. How to regulate the interfacial polymerization process while improving the antibiotic desalination efficiency and water permeability is the key to popularize the application of polyamide nanofiltration membranes. SUMMARY

[0005] In view of the above existing problems in the prior art, the primary object of the present application is to provide a preparation method of a hesperidin-regulated polyamide nanofiltration membrane, which regulates the reaction of amine monomers and acyl chloride monomers in the interfacial polymerization process by adding an additive hesperidin to the water-phase solution, so that the prepared polyamide nanofiltration membrane not only maintains excellent water flux and antibiotic rejection rate, but also has excellent inorganic salt / antibiotic selectivity.

[0006] The second object of the present application is to provide a hesperidin-regulated polyamide nanofiltration membrane prepared by the preparation method.

[0007] A third object of the present application is to provide the application of the said hesperidin-regulated polyamide nanofiltration membrane in wastewater and sewage treatment.

[0008] A fourth object of the present application is to provide the application of the said hesperidin-regulated polyamide nanofiltration membrane in the selective separation of inorganic salts / antibiotics or the recovery of antibiotics.

[0009] In order to achieve the above-mentioned objects, the present application is realized by the following technical solutions: The present application claims a preparation method of a hesperidin-regulated polyamide nanofiltration membrane, comprising the following steps: S1. The surface of the base membrane is contacted with an aqueous solution, and the aqueous solution is removed after standing; S2. The surface of the base membrane after removing the aqueous solution in step S1 is contacted with an organic phase solution to perform interfacial polymerization, and a polyamide nanofiltration membrane is obtained; The aqueous solution is an aqueous solution containing hesperidin, amine monomer and water; in the aqueous solution, the mass-volume ratio of hesperidin and water is 5-10:1 g / L, and the mass-volume ratio of amine monomer and water is 4-6:1 g / L; The organic phase solution is a mixed solution containing acyl chloride monomer and organic solvent; in the organic phase solution, the mass-volume ratio of the acyl chloride monomer and the organic solvent is 1.3-2:1 g / L; The structure of the hesperidin is shown in the following formula (I):

[0010] (I).

[0011] The inventors found through long-term research that, in the preparation process of the polyamide nanofiltration membrane, the addition of hesperidin with a twisted structure in the reaction system will cause part of the hesperidin molecules to enter the organic phase solution with the amine monomer in the water phase. The hesperidin will occupy the distribution space of the amine monomer and the acyl chloride monomer in the IP process and will not participate in the IP reaction, thus creating free cavities (forming free volumes) in the polyamide layer. These free cavities, on the one hand, increase the water permeation flux of the polyamide nanofiltration membrane, and on the other hand, reduce the inorganic salt retention (while maintaining the same antibiotic retention), thus improving the selective separation of inorganic salts / antibiotics. In addition, the hesperidin can be adsorbed on the surface of the base membrane through π-π interaction and hydrophobic-hydrophobic interaction, and the hesperidin molecules have abundant alcohol hydroxyl and phenolic hydroxyl groups, which are conducive to the enrichment of more amine monomers on the surface of the base membrane through hydrogen bonding or electrostatic interaction; the hesperidin molecules in the aqueous solution also reduce the interfacial tension of the aqueous solution, which promotes the reaction of the amine monomer and the acyl chloride monomer at the water-organic interface, increases the interfacial instability of the IP reaction, and is conducive to the generation of a patterned polyamide layer, thus further significantly improving the water permeation flux of the polyamide nanofiltration membrane.

[0012] Further, the inventors found that the concentrations of hesperidin and amine monomer in the aqueous solution and the concentration of acyl chloride monomer in the organic solution have a great influence on the formation of the polyamide nanofiltration membrane. Under specific concentrations of hesperidin and amine monomer and specific concentration of acyl chloride monomer, the polyamide nanofiltration membrane prepared has excellent water flux, antibiotic retention rate and inorganic salt / antibiotic selectivity.

[0013] Compared with the conventional polyamide nanofiltration membrane, the polyamide nanofiltration membrane prepared by the application has higher free volume and higher effective filtration area, which can effectively enhance the inorganic salt / antibiotic selectivity of the polyamide nanofiltration membrane and greatly reduce the operating pressure and energy consumption of the conventional nanofiltration membrane. The application uses environmentally friendly and low-cost hesperidin with twisted structure, which not only eliminates the need for adding catalysts in the reaction process, but also solves the problems of toxicity and high cost of additives used in the conventional interfacial polymerization process.

[0014] Preferably, the amine monomer is selected from one or more of piperazine, m-phenylenediamine, ethylenediamine, polyvinylamine, diethylenetriamine and polyethyleneimine; and / or The acyl chloride monomer is selected from one or more of 1,3,5-benzene tricarbonyl chloride, terephthaloyl chloride and isophthaloyl chloride; and / or The base membrane is polysulfone, polyethersulfone, polyvinylidene fluoride, polyacrylonitrile, polyethylene, polyvinyl chloride or polytetrafluoroethylene.

[0015] Preferably, in the aqueous solution, the mass-volume ratio of hesperidin and water is 6.5-8.5:1 g / L. Further preferably, in the aqueous solution, the mass-volume ratio of hesperidin and water is 7-8:1 g / L. More preferably, in the aqueous solution, the mass-volume ratio of hesperidin and water is 7.5:1 g / L. Under the premise of the preferred amount of hesperidin added, the polyamide nanofiltration membrane prepared has more excellent water flux, antibiotic retention rate and inorganic salt / antibiotic selectivity.

[0016] Preferably, in the aqueous solution, the mass-volume ratio of amine monomer and water is 4.5-5.5:1 g / L. Further preferably, the mass-volume ratio of amine monomer and water is 5:1 g / L. Under the premise of the preferred amount of amine monomer added, the polyamide nanofiltration membrane prepared has more excellent water flux, antibiotic retention rate and inorganic salt / antibiotic selectivity.

[0017] Preferably, the mass / volume ratio of the acyl chloride monomer and the organic solvent in the organic phase solution is 1.4-1.7:1 g / L. Further preferably, the mass / volume ratio of the acyl chloride monomer and the organic solvent is 1.5-1.6:1 g / L. More preferably, the mass / volume ratio of the acyl chloride monomer and the organic solvent is 1.5:1 g / L. Under the premise of the preferred amount of amine monomer addition, the polyamide nanofiltration membrane prepared has more excellent water flux, antibiotic retention rate and inorganic salt / antibiotic selectivity.

[0018] Preferably, the organic solvent is selected from one or more of hexane, heptane, octane, decane, cyclohexane.

[0019] Preferably, in the step S1, the standing time is 0.5-15 min; and / or in the step S2, the interfacial polymerization time is 0.05-5 min.

[0020] Further, the present application claims to protect the hesperidin-regulated polyamide nanofiltration membrane prepared by the above preparation method.

[0021] Preferably, the hesperidin-regulated polyamide nanofiltration membrane has a molecular weight cut-off of 330-350 Da. More specifically, the hesperidin-regulated polyamide nanofiltration membrane has a molecular weight cut-off of 340 Da.

[0022] Further, the present application claims to protect the above hesperidin-regulated polyamide nanofiltration membrane for use in wastewater and sewage treatment.

[0023] Further, the present application claims to protect the above hesperidin-regulated polyamide nanofiltration membrane for use in inorganic salt / antibiotic selective separation or antibiotic recovery.

[0024] Preferably, the antibiotic is selected from at least one of tetracycline antibiotics, fluoroquinolone antibiotics, macrolide antibiotics, fluoroquinolone antibiotics. More specifically, the tetracycline antibiotics include but are not limited to tetracycline. The fluoroquinolone antibiotics include but are not limited to enrofloxacin. The macrolide antibiotics include but are not limited to erythromycin. The fluoroquinolone antibiotics include but are not limited to norfloxacin. Relative to other antibiotics, the polyamide nanofiltration membrane provided by the present application not only has more excellent antibiotic retention rate for the above-mentioned types of antibiotics, but also has more excellent inorganic salt / antibiotic selectivity.

[0025] Preferably, the molecular weight of the antibiotic is ≥300 Da. More preferably, the molecular weight of the antibiotic is ≥340 Da. More preferably, the molecular weight of the antibiotic is ≥400 Da. Further preferably, the molecular weight of the antibiotic is 400-2000 Da. The polyamide nanofiltration membrane provided by the present application has more excellent retention effect for the above-mentioned preferred molecular weight of antibiotics.

[0026] Preferably, the inorganic salt includes, but is not limited to, NaCl.

[0027] Compared with the prior art, the present application has the following beneficial effects: The present application provides a preparation method of hesperidin-regulated polyamide nanofiltration membrane. By adding hesperidin as an additive in an aqueous solution, the reaction of amine monomers and acyl chloride monomers in the interfacial polymerization process is regulated, so that the polyamide nanofiltration membrane prepared has excellent water flux and antibiotic retention rate, and also has excellent inorganic salt / antibiotic selectivity. BRIEF DESCRIPTION OF DRAWINGS

[0028] Figure 1 The scanning electron microscope graph of the surface of the polyamide nanofiltration membrane synthesized for Example 2 and Comparative Example 1. Among them, Figure 1 a in the above is the scanning electron microscope graph of the surface of the polyamide nanofiltration membrane synthesized for Comparative Example 1; Figure 1 b in the above is the scanning electron microscope graph of the surface of the polyamide nanofiltration membrane synthesized for Example 1.

[0029] Figure 2 The schematic diagram of the free volume (FFV) of the polyamide nanofiltration membrane in Example 2 and Comparative Example 1 by molecular dynamics simulation. Among them, Figure 2 a in the above is the schematic diagram of the FFV of the polyamide nanofiltration membrane in Comparative Example 1 by molecular dynamics simulation; Figure 2 b in the above is the schematic diagram of the FFV of the polyamide nanofiltration membrane in Example 2 by molecular dynamics simulation.

[0030] Figure 3 The retention rate of the polyamide nanofiltration membrane synthesized for Examples 1-3 to neutral organic molecules with different molecular weights. DETAILED DESCRIPTION

[0031] The present application will be further described below in conjunction with the description and specific examples, but the examples do not limit the present application in any form. Unless otherwise specified, the reagents, methods and equipment used in the present application are conventional reagents, methods and equipment in the technical field.

[0032] Preparation of polyamide nanofiltration membrane in Example 1 (1) 5.0 g of piperazine and 7.5 g of hesperidin (Yuzhou Biology, CAS: 520-26-3, the structural formula is shown in formula (I) below) were added to a 1 L deionized water solution, and stirred at a stirring speed of 100 rpm for 10 min to obtain a piperazine-hesperidin mixed aqueous solution;

[0033] (I) Molecular structure of hesperidin; (2) Pour the mixed aqueous solution of piperazine and hesperidin onto the surface of the polysulfone-based membrane (US020, Kechuang Ruiyang), and stand for 3 min. After the solution is poured off, the excess liquid droplets on the surface of the base membrane are removed by an air knife to obtain a base membrane with piperazine and hesperidin adsorbed thereon; (3) Add 1.5 g of 1,3,5-benzene tricarbonyl chloride to 1 L of n-hexane solution, and obtain an organic phase solution after complete dissolution. Pour the organic phase solution onto the surface of the base membrane treated in step (2), and stand for 1 min to perform interfacial polymerization. After the solution on the surface of the base membrane is poured off, the unreacted 1,3,5-benzene tricarbonyl chloride on the surface of the base membrane is removed by washing with an n-hexane solution, and the base membrane is placed in a 60°C oven for heat treatment for 10 min to obtain a polyamide nanofiltration membrane.

[0034] Example 2 Preparation of a polyamide nanofiltration membrane The difference between this example and Example 1 is that in step (1), the amount of hesperidin added is 5.0 g.

[0035] Example 3 Preparation of a polyamide nanofiltration membrane The difference between this example and Example 1 is that in step (1), the amount of hesperidin added is 10.0 g.

[0036] Example 4 Preparation of a polyamide nanofiltration membrane The difference between this example and Example 1 is that in step (2), the mass-volume ratio of 1,3,5-benzene tricarbonyl chloride to n-hexane solution is 2.0:1 g / L.

[0037] Comparative Example 1 The difference between this comparative example and Example 1 is that in step (1), no hesperidin is added.

[0038] Comparative Example 2 The difference between this comparative example and Example 1 is that in step (1), aloe glycoside is used instead of hesperidin.

[0039] Comparative Example 3 This comparative example uses a commercial polyamide nanofiltration membrane Dow-Filmtec NF270.

[0040] Comparative Example 4 This comparative example uses a commercial polyamide nanofiltration membrane Dow-Filmtec NF90.

[0041] Comparative Example 5 The difference between this comparative example and Example 1 is that in step (1), 2.5 g of piperazine is added to 1 L of deionized water solution.

[0042] Comparative Example 6 The difference between this comparative example and Example 1 is that in step (1), 7.5 g of piperazine is added to 1 L of deionized water solution.

[0043] Comparative Example 7 The difference between this comparative example and Example 1 is that in step (1), 2.5g piperazine was added to 1L of deionized water, but no hesperidin was added.

[0044] Comparative Example 8 The difference between this comparative example and Example 1 is that in step (1), 7.5g of piperazine was added to 1L of deionized water, but no hesperidin was added.

[0045] Comparative Example 9 The difference between this comparative example and Example 1 is that in step (2), the mass-to-volume ratio of 1,3,5-benzenetricarboxyl chloride to n-hexane solution is 1.0:1 g / L.

[0046] Test Example 1: Characterization of Polyamide Nanofiltration Membrane The surface morphology of the polyamide nanofiltration membranes synthesized in Example 2 and Comparative Example 1 was observed using a field emission scanning electron microscope (FESEM, Quanta 400). The polyamide nanofiltration membranes were dried in a vacuum drying oven beforehand. Before observation, conductive adhesive was applied to a copper stage of the sample, and the square-cut polyamide nanofiltration membranes were fixed onto the conductive adhesive. The sample surface was then sputter-coated with gold and observed under an accelerating voltage of 5 kV.

[0047] Figure 1 Scanning electron microscope images of the surfaces of the polyamide nanofiltration membranes prepared in Example 1 and Comparative Example 1. Figure 1 It can be seen that the polyamide selective layer of Comparative Example 1 has a typical nodular morphology, which is formed by the reaction of piperazine and 1,3,5-benzenetricarboxylic acid chloride on the surface of the porous base membrane. Example 1 is a polyamide nanofiltration membrane prepared by adding hesperidin, which is made from... Figure 1 It can be seen that when hesperidin is added to the aqueous solution, the polyamide selective layer on the membrane surface changes from a nodular morphology to a wrinkled morphology, which means that the polyamide regulated by hesperidin has a larger specific surface area, which will significantly increase the water permeation flux of the membrane.

[0048] Molecular dynamics simulations were used to investigate the free volume of the polyamide nanofiltration membranes in Example 2 and Comparative Example 1. In Example 2, 120 piperazine molecules, 90 1,3,5-benzenetricarboxyl chloride molecules, and 20 hesperidin molecules were placed in the simulation chamber (created using Packmol software). In Comparative Example 1, only 120 piperazine molecules and 90 1,3,5-benzenetricarboxyl chloride molecules were placed. The crosslinking monomers were set to only piperazine and 1,3,5-benzenetricarboxyl chloride, and the degree of crosslinking was set to 65.5% for both systems. After the simulations were completed, the hesperidin molecules in the Example 2 simulation chamber were removed, while the Comparative Example 1 simulation chamber remained unchanged. The free volumes of the two systems were then analyzed.

[0049] Figure 2 The crosslinking simulation products of Example 2 and Comparative Example 1 after simulation and the respective free volumes are shown. Figure 2 It can be seen that after the addition of hesperidin, the FFV of the corresponding polyamide selective layer is obviously increased, which helps to improve the permeation flux of the membrane. The free volume of the polyamide selective layer in Comparative Example 1 without the addition of hesperidin is 18.56%, while the free volume of the polyamide selective layer in Example 2 after the addition of hesperidin is 43.21%.

[0050] Test Example 2 Water permeation flux, antibiotic and salt rejection rate experiment of polyamide nanofiltration membrane The pure water permeation flux, NaCl rejection rate and tetracycline rejection rate of the polyamide nanofiltration membranes prepared in the comparative examples and examples were tested, and the specific method was as follows: (1) Pure water flux determination: A cross-flow filtration device (CF016D; Sterlitech, USA) was used for the filtration experiment, and the experimental parameters were as follows: the effective area of the polyamide nanofiltration membrane was 16 x 10 -4 m 2 , the temperature of the filtration experiment was 25±2 ℃, and the test pressure was 5 bar.

[0051] At the beginning of the test, after the pure water was pre-pressed at a pressure of 5 bar for 60 min to reach a stable flux, the volume of the pure water passing through the nanofiltration membrane was continuously measured within a certain time, and the permeation flux J W (Lm -2 h -1 bar -1 ) of the composite nanofiltration membrane to be tested was calculated, and the calculation formula was as follows: (1) In the formula, V is the permeation volume, m 3 ; A is the effective area of the membrane, m 2 ; t is the sample filtration time, s; and ΔP is the pressure of the device operation, bar.

[0052] (2) Inorganic salt and antibiotic rejection rate and selectivity determination: A cross-flow filtration device was used for the filtration experiment, and the rejection rate R of the polyamide nanofiltration membranes prepared in the examples and comparative examples to tetracycline or NaCl was obtained, and the selective permeability of the polyamide nanofiltration membranes to NaCl / tetracycline was characterized.

[0053] A 1000 mg L -1 NaCl solution and a 10 mg L -1tetracycline as the raw material liquid, when using different raw material liquids for testing, the raw material liquid is pre-pressed at 5 bar for 30 min to reach a stable flux, the concentrated liquid and the permeate liquid are collected, the concentrations of the two are tested, and the salt rejection rate R (%) is calculated by formula (2). The selectivity coefficient a of NaCl / tetracycline is calculated by formula (3): (2) (3) wherein, C p and C F respectively represent the solute concentrations mg / L of the permeate liquid and the concentrated liquid -1 .

[0054] (3) Molecular weight cut-off determination A cross-flow filtration device is used for the filtration experiment, the rejection rates R (%) of the polyamide nanofiltration membrane to four neutral molecules: glycerol (92 Da), glucose (180 Da), sucrose (342 Da) and raffinose (504 Da) are obtained, and the molecular weight cut-off of the polyamide nanofiltration membrane is characterized.

[0055] 200 mg / L -1 of the above four neutral molecules are respectively prepared as the raw material liquid, when using different raw material liquids for testing, the raw material liquid is pre-pressed at 5 bar for 30 min to reach a stable flux, the concentrated liquid and the permeate liquid are collected, the concentrations of the two are tested by TOC (TOC-L, Shimadzu), and the salt rejection rate R (%) is calculated by formula (2).

[0056] The test results of the pure water permeation flux, tetracycline rejection rate and NaCl / tetracycline selectivity of the polyamide nanofiltration membranes prepared in the comparative examples and the examples are compared with the performance of the separation membranes of the existing commercial membranes, and the specific comparison results are shown in Table 1.

[0057] Table 1

[0058] As can be seen from Table 1, the polyamide nanofiltration membrane prepared by using hesperidin to regulate interfacial polymerization in the application has excellent water permeability, high antibiotic rejection rate and antibiotic / NaCl selectivity. More specifically, the water flux of the polyamide nanofiltration membrane is ≥22.9 Lm -2 h -1 bar -1 , the tetracycline rejection rate is ≥98.7%, and the NaCl / tetracycline selectivity is ≥49.2. More preferably, the water flux of the polyamide nanofiltration membrane is ≥36.5 Lm -2 h -1 bar -1, the tetracycline rejection rate is greater than or equal to 98.7%, and the NaCl / tetracycline selectivity is greater than or equal to 50.4; most preferably, the water flux of the polyamide nanofiltration membrane is greater than or equal to 36.9 Lm -2 h -1 bar -1 , the tetracycline rejection rate is greater than or equal to 99.2%, and the NaCl / tetracycline selectivity is greater than or equal to 95.6.

[0059] As can be seen from Example 1, Example 2 and Example 3, when the addition amount of hesperidin in the aqueous phase solution is within a certain range, the polyamide nanofiltration membrane prepared has more excellent antibiotic rejection rate and antibiotic / NaCl selectivity.

[0060] As can be seen from Example 1, Example 4, Comparative Examples 5-6 and Comparative Example 9, when the addition amount of piperazine in the aqueous phase solution or the addition amount of 1,3,5-benzene tricarbonyl chloride in the organic phase solution is within a certain range, the polyamide nanofiltration membrane prepared has more excellent water flux, antibiotic rejection rate and antibiotic / NaCl selectivity.

[0061] As can be seen from Example 1, Comparative Example 1 and Comparative Examples 7-8, when hesperidin is not added in the system, the water flux and NaCl / antibiotic selectivity decrease sharply, which indicates that hesperidin can form a patterned polyamide selective layer and a larger free volume, which is more conducive to improving the water permeation flux and NaCl / antibiotic selectivity of the polyamide nanofiltration membrane.

[0062] As can be seen from Example 1, Comparative Examples 2-4, the polyamide nanofiltration membrane provided by the present application has a performance far superior to that of the existing commercial membranes NF270 and NF90; in addition, the water flux and NaCl / tetracycline selectivity are both low when the existing aloin is used as an additive.

[0063] As shown in Table 2, the polyamide nanofiltration membrane provided by the present application has a lower rejection rate for sulfamethoxazole and a lower NaCl / sulfamethoxazole selectivity. Figure 3

[0064] Test Example 3: Test of polyamide nanofiltration membrane on different antibiotics (1) The polyamide nanofiltration membrane prepared in Example 1 was tested on sulfamethoxazole according to the test method of Test Example 2, and the specific results are shown in Table 2.

[0065] Table 2

[0066] As shown in Table 2, the polyamide nanofiltration membrane provided by the present application has a lower rejection rate for sulfamethoxazole and a lower NaCl / sulfamethoxazole selectivity.

[0067] ​The foregoing examples are illustrative only and are not intended to limit the scope of the methods described herein. The appended claims are intended to claim as broad a range as possible as the inventors can conceive of at the time of filing. The examples presented herein are intended to demonstrate the inventors' knowledge of the present application and are not intended to limit the scope of the claims. Some of the numerical ranges recited in the claims are inclusive of the integers within the defined range. Unless otherwise specified, all ranges include endpoints.

Claims

1. A method for preparing a hesperidin-modulated polyamide nanofiltration membrane, characterized in that, The method comprises the following steps: S1. contacting the surface of the base film with an aqueous solution, standing, and removing the aqueous solution; S2. contacting the surface of the base film after removing the aqueous solution in step S1 with an organic phase solution, and performing interfacial polymerization to obtain a polyamide nanofiltration membrane; The aqueous solution comprises hesperidin, an amine monomer, and water; in the aqueous solution, the mass-volume ratio of hesperidin to water is 5-10:1 g / L, and the mass-volume ratio of the amine monomer to water is 4-6:1 g / L; The organic phase solution is a mixed solution comprising an acid chloride monomer and an organic solvent; in the organic phase solution, the mass-volume ratio of the acid chloride monomer to the organic solvent is 1.3-2:1 g / L; The structure of the hesperidin is shown in the following formula (I): （I）。 2. The method of claim 1, wherein, The amine monomer is selected from one or more of piperazine, m-phenylenediamine, ethylenediamine, polyvinylamine, diethylenetriamine, and polyethyleneimine; and / or The acid chloride monomer is selected from one or more of 1,3,5-benzene tricarbonyl chloride, terephthaloyl chloride, and isophthaloyl chloride; and / or The base film is poly sulfone, poly ether sulfone, polyvinylidene fluoride, polyacrylonitrile, polyethylene, polyvinyl chloride, or polytetrafluoroethylene.

3. The preparation method according to claim 1, characterized in that, In the aqueous solution, the mass-volume ratio of hesperidin to water is 6.5-8.5:1 g / L.

4. The preparation method according to claim 3, characterized in that, In the aqueous solution, the mass-volume ratio of the amine monomer to water is 4.5-5.5:1 g / L.

5. The preparation method according to claim 3 or 4, characterized in that, In the organic phase solution, the mass-volume ratio of the acid chloride monomer to the organic solvent is 1.4-1.7:1 g / L.

6. The method of claim 1, wherein the step of forming the first and second layers is performed by a process selected from the group consisting of: sputtering, evaporation, and chemical vapor deposition. The organic solvent is selected from one or more of hexane, heptane, octane, decane, and cyclohexane.

7. The method of claim 1, wherein the step of forming the first and second layers is performed by a process selected from the group consisting of: sputtering, evaporation, and chemical vapor deposition. In step S1, the standing time is 0.5-15 min; and / or In step S2, the interfacial polymerization time is 0.05-5 min.

8. The hesperidin-regulated polyamide nanofiltration membrane obtained by the preparation method of any one of claims 1-7.

9. The hesperidin-regulated polyamide nanofiltration membrane of claim 8 for use in wastewater and sewage treatment.

10. The hesperidin-regulated polyamide nanofiltration membrane of claim 8 for use in selective separation of inorganic salts / antibiotics or recovery of antibiotics.

Images