Antibacterial antifouling reverse osmosis membrane and preparation method thereof

Abstract

The application relates to an antibacterial and antifouling reverse osmosis membrane and a preparation method thereof, and comprises the following steps: (1) uniformly dissolving a multiacyl chloride group organic compound in an organic solvent, then adding cyclodextrin, and carrying out ultrasonic treatment to obtain a cyclodextrin-organic acyl chloride inclusion compound solution; dispersing antibacterial nanoparticles in water, then adding an amino silane coupling agent, and stirring and dispersing to obtain a functionalized antibacterial nanoparticle suspension with amino groups on the surface; (2) uniformly coating the cyclodextrin-organic acyl chloride inclusion compound solution to one surface of a prefabricated reverse osmosis membrane, removing the excess solution on the surface after standing, and then coating the functionalized antibacterial nanoparticle suspension with amino groups on the surface on the surface with the cyclodextrin-organic acyl chloride inclusion compound, removing the excess solution on the surface after standing, and carrying out thermal drying to obtain the antibacterial and antifouling reverse osmosis membrane. The reverse osmosis membrane has excellent stability, small membrane sheet water flux attenuation, obviously improved antifouling capacity, and excellent antibacterial capacity.

Description

Technical Field

[0001] This invention relates to the field of water treatment membrane synthesis technology, specifically to an antibacterial and antifouling reverse osmosis membrane and its preparation method. Background Technology

[0002] Membrane separation technology, with its combined functions of separation, concentration, purification, and refining, along with its high efficiency, energy saving, environmental friendliness, and ease of control, has been widely applied in the food and pharmaceutical industries, generating significant economic and social benefits. It has become one of the most important methods in separation science today. Reverse osmosis technology is a pressure-driven membrane separation technique. Based on the selective permeability of reverse osmosis membranes—allowing only water molecules to pass through while retaining ions or small molecules—the pressure difference across the membrane serves as the driving force to achieve the separation of mixtures. However, in actual operation, the complexity of water quality and the variability of the environment cause a layer of contaminants to easily adhere to the surface of the reverse osmosis membrane, significantly reducing its separation efficiency.

[0003] To reduce membrane fouling, the surface of the polyamide desalination layer in reverse osmosis membranes is typically hydrophilically modified during production to reduce hydrophobicity and minimize contamination. Current manufacturing processes usually employ water-soluble polymers, such as polyvinyl alcohol (PVA), to directly modify the reverse osmosis membrane surface. However, due to PVA's high water solubility, it becomes unstable on the polyamide surface and easily detaches. To fix the PVA molecules, crosslinking agents are used to crosslink them, forming a dense network structure. However, coating the reverse osmosis membrane with crosslinked PVA significantly reduces its water flux, impacting membrane performance. Summary of the Invention

[0004] The technical problem this invention aims to solve is how to improve the surface antifouling and antibacterial properties of reverse osmosis membranes while ensuring the water flux of the membrane. Therefore, this invention provides an antibacterial and antifouling reverse osmosis membrane and its preparation method. This invention modifies the surface of existing reverse osmosis membranes by forming antibacterial nanoparticle cross-linked cyclodextrin inclusion complexes on the surface, thereby giving the reverse osmosis membrane surface better antifouling and antibacterial properties.

[0005] To achieve the above objectives, the present invention is implemented through the following technical solution:

[0006] A method for preparing an antibacterial and antifouling reverse osmosis membrane includes the following steps:

[0007] (1) Dissolve the polyacryl chloride group organic compound uniformly in an organic solvent, then add cyclodextrin, and sonicate to obtain a cyclodextrin-organic acryl chloride inclusion complex solution;

[0008] Antibacterial nanoparticles were dispersed in water, and then an aminosilane coupling agent was added. The mixture was stirred and dispersed to obtain a suspension of functionalized antibacterial nanoparticles with amino groups on the surface.

[0009] (2) The cyclodextrin-organic acyl chloride inclusion complex solution is uniformly coated onto one surface of the pre-made reverse osmosis membrane. After standing, the excess solution on the surface is removed. The functionalized antibacterial nanoparticle suspension with amino groups on the surface of the cyclodextrin-organic acyl chloride inclusion complex is superimposed and coated. After standing, the excess solution on the surface is removed. After thermal drying, the antibacterial and antifouling reverse osmosis membrane is obtained.

[0010] The reaction principle of the above method is as follows: Since cyclodextrin has a hydrophilic outer shell and a hydrophobic inner cavity, after mixing the polyacrylamide chloride group organic compound with cyclodextrin, the polyacrylamide chloride group organic compound will enter the inner cavity of cyclodextrin to form an inclusion complex. Then, multiple acrylamide chloride groups will chemically bond with multiple amino groups on the surface of antibacterial particles to obtain a reverse osmosis membrane with an antibacterial nanoparticle-cyclodextrin coating.

[0011] Furthermore, the polyacrylamide group organic compound is selected from one of pyromellitic methyl methacrylate, isophthaloyl chloride, orthophthaloyl chloride, 2,6-naphthoyl chloride, 4,4'-biphenyldiacetyl chloride, 4,4'-oxobis(benzoyl chloride), 1,4-cyclohexadiyl chloride, azelaic chloride, adipic acid chloride, sebacic acid chloride, octanoic acid chloride, glutaric acid chloride, and 1,7-heptanoic acid chloride.

[0012] Furthermore, the antibacterial nanoparticles are nano-zinc oxide; the organic solvent is cyclohexane; and the prefabricated reverse osmosis membrane is a polyamide reverse osmosis membrane with a flux of 45 LMH-80 LMH.

[0013] Furthermore, the aminosilane coupling agent is selected from one or more of 3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, 3-aminopropylmethyldimethoxysilane, N-2-aminoethyl-3-aminopropyltrimethoxysilane, and 3-diethylenetriaminopropyltrimethoxysilane.

[0014] Further, the mass ratio of the polyacrylamide chloride organic compound, the cyclodextrin, and the organic solvent is 0.1-1.5:0.05-0.5:100; and the ultrasonic treatment time is at least 0.5 hours.

[0015] Furthermore, the mass ratio of the antibacterial nanoparticles, the aminosilane coupling agent, and water is 0.02-0.3:0.5-4:100; and the stirring and dispersion time is 1-3 hours.

[0016] Further, the mass ratio of the polyacrylamide chloride group organic compound to the aminosilane coupling agent is 0.1-1.5:0.5-4; the coating amount of the cyclodextrin-organic acrylamide chloride inclusion complex solution on the surface of the pre-fabricated reverse osmosis membrane is 50-200 g / m². 2 The coating amount of the amino-functionalized antibacterial nanoparticle suspension on the surface containing cyclodextrin-organic acyl chloride inclusion complex is 50-100 g / m². 2 The settling time is at least 30 seconds; the thermal drying temperature is 60-80℃. The coating amount refers to the weight of the solution coated per square meter of film surface.

[0017] The present invention also provides an antibacterial and antifouling reverse osmosis membrane obtained by the above preparation method.

[0018] Beneficial technical effects:

[0019] This invention prepares an antibacterial and antifouling reverse osmosis membrane by forming an antibacterial nanoparticle-cyclodextrin coating on the surface of a commercial reverse osmosis membrane. Compared with traditional reverse osmosis membranes with polyvinyl alcohol coatings, the reverse osmosis membrane of this invention has excellent stability, smaller membrane water flux attenuation, significantly improved antifouling ability, and excellent antibacterial ability.

[0020] The nano zinc oxide-cyclodextrin coating involved in this invention has the following characteristics:

[0021] Cyclodextrin molecules have a unique hollow frustum-shaped three-dimensional structure with an inner hydrophobic cavity and an outer hydrophilic edge. This structure provides little resistance to water molecules during separation, and thus the antibacterial nanoparticle-cyclodextrin coating on the surface has little impact on the water flux of the reverse osmosis membrane. The cyclodextrin structure provides a large number of hydroxyl groups, which is beneficial to improving the hydrophilicity of the coating.

[0022] This invention effectively solves the instability problem of traditional antifouling membranes by using antibacterial nanoparticles, such as nano-zinc oxide cross-linked cyclodextrin inclusion complexes. Simultaneously, the structure of this invention also helps reduce the adhesion of contaminants such as microorganisms and colloidal particles to the reverse osmosis membrane surface. The antibacterial nanoparticles, such as nano-zinc oxide, can slowly release zinc ions (Zn). 2+ This process kills bacteria, giving the composite membrane excellent antibacterial properties. Attached Figure Description

[0023] Figure 1 This is a schematic diagram illustrating the reaction principle between materials in Example 1;

[0024] Figure 2 The images show the surface SEM morphology of the antibacterial and antifouling reverse osmosis membrane with nano zinc oxide-cyclodextrin coating in Example 1 before and after immersion in 4wt% sodium hydroxide aqueous solution. (A) is the SEM image before immersion, and (B) is the SEM image after immersion. The scale bars in the figures are all 1μm.

[0025] Figure 3 The graph shows the antibacterial properties of the pre-fabricated reverse osmosis membrane, the cross-linked PVA coated membrane of Comparative Example 2, and the reverse osmosis membrane of Example 1. In the graph, RO represents reverse osmosis. Detailed Implementation

[0026] The technical solutions of the present invention will be clearly and completely described below with reference to the embodiments and accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. The following description of at least one exemplary embodiment is merely illustrative and is in no way intended to limit the present invention or its application or use. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection of the present invention.

[0027] Unless otherwise specifically stated, the numerical values ​​set forth in these embodiments do not limit the scope of the invention. Techniques and methods known to those skilled in the art may not be discussed in detail, but where appropriate, such techniques and methods should be considered part of the specification. In all examples shown and discussed herein, any specific values ​​should be interpreted as merely exemplary and not as limitations. Therefore, other examples of exemplary embodiments may have different values.

[0028] The prefabricated reverse osmosis membrane used below is a traditional commercially available polyamide reverse osmosis membrane. The layers, from bottom to top, are PET nonwoven fabric layer, polysulfone layer, and polyamide layer (surface layer). The prefabricated reverse osmosis membrane has a flux of 45 LMH-80 LMH and is a mass-produced product of the production line of Entai Environmental Protection Technology (Changzhou) Co., Ltd.

[0029] Comparative Example 1

[0030] This comparative case uses a reverse osmosis membrane with a polyvinyl alcohol coating on its surface, and the preparation method is as follows:

[0031] Dissolve 0.5g of polyvinyl alcohol (model 05-88) in 100mL of water, and after thorough mixing, prepare a coating solution. Apply 10g of the coating solution evenly to the surface of a pre-fabricated reverse osmosis membrane (surface area 0.1m²). 2 After standing for 30 seconds, excess solution is removed using a pressure roller, and the membrane is dried in an 80°C oven to constant weight to obtain a reverse osmosis membrane with a polyvinyl alcohol coating.

[0032] Comparative Example 2

[0033] This comparative case uses a reverse osmosis membrane with a cross-linked polyvinyl alcohol coating on its surface, and the preparation method is as follows:

[0034] Dissolve 0.5g of polyvinyl alcohol (model 05-88) in 100mL of water, add 0.5g of glutaraldehyde, adjust the pH to 3.0 using sulfuric acid (0.5wt%), and mix thoroughly to obtain the coating solution. Apply 10g of the coating solution evenly to the surface of the prefabricated reverse osmosis membrane (surface area 0.1m²). 2 After standing for 30 seconds, excess solution is removed using a pressure roller, and the membrane is dried in an 80°C oven to constant weight to obtain a reverse osmosis membrane with a cross-linked polyvinyl alcohol coating.

[0035] Example 1

[0036] A method for preparing an antibacterial and antifouling reverse osmosis membrane includes the following steps:

[0037] (1) Dissolve 1.0 g of pyromellitic chloride uniformly in 100 g of cyclohexane solution, slowly add 0.4 g of cyclodextrin, sonicate for 1 h to mix evenly, and let stand to obtain a cyclohexane solution of cyclodextrin-pyromellitic chloride inclusion complex for later use.

[0038] 0.1g of nano zinc oxide was ultrasonically dispersed in 100g of pure water, and 1.0g of 3-aminopropyltrimethoxysilane was added. The mixture was stirred for 2h to obtain a functionalized nano zinc oxide suspension aqueous solution with amino groups on the surface.

[0039] (2) A cyclohexane solution of 10g of cyclodextrin-pyromellitic acid chloride inclusion complex was uniformly coated onto one surface of the pre-fabricated reverse osmosis membrane (surface area 0.1m²). 2 Let it stand for 30 seconds, then use a pressure roller to remove excess solution from the surface;

[0040] A 10g aqueous solution of functionalized nano zinc oxide with amino groups on the surface was uniformly coated onto the surface of the membrane containing cyclodextrin-organic acyl chloride inclusion complex. After standing for 60 seconds, the excess solution on the membrane surface was poured off, and the membrane was dried in an oven at 80℃ to obtain an antibacterial and antifouling reverse osmosis membrane with a nano zinc oxide-cyclodextrin composite coating on the surface.

[0041] The reaction principle between materials in this embodiment is as follows: Figure 1 As shown.

[0042] Example 2

[0043] A method for preparing an antibacterial and antifouling reverse osmosis membrane includes the following steps:

[0044] (1) Dissolve 1.0 g phthaloyl chloride uniformly in 100 g cyclohexane solution, slowly add 0.4 g cyclodextrin, sonicate for 1 h to mix evenly, and let stand to obtain a cyclohexane solution of cyclodextrin-phthaloyl chloride inclusion complex for later use.

[0045] 0.1g of nano zinc oxide was ultrasonically dispersed in 100g of pure water, and 1.0g of 3-aminopropyltrimethoxysilane was added. The mixture was stirred for 2h to obtain a functionalized nano zinc oxide suspension aqueous solution with amino groups on the surface.

[0046] (2) A cyclohexane solution of 10g of cyclodextrin-phthaloyl chloride inclusion complex was uniformly coated onto one surface of the pre-fabricated reverse osmosis membrane (surface area 0.1m²). 2 Let it stand for 30 seconds, then use a pressure roller to remove excess solution from the surface;

[0047] A 10g aqueous solution of functionalized nano zinc oxide with amino groups on the surface was uniformly coated onto the surface of the membrane containing cyclodextrin-organic acyl chloride inclusion complex. After standing for 60 seconds, the excess solution on the membrane surface was poured off, and the membrane was dried in an oven at 80℃ to obtain an antibacterial and antifouling reverse osmosis membrane with a nano zinc oxide-cyclodextrin composite coating on the surface.

[0048] Example 3

[0049] A method for preparing an antibacterial and antifouling reverse osmosis membrane includes the following steps:

[0050] (1) Dissolve 1.0 g of pyromellitic chloride uniformly in 100 g of cyclohexane solution, slowly add 0.4 g of cyclodextrin, sonicate for 1 h to mix evenly, and let stand to obtain a cyclohexane solution of cyclodextrin-pyromellitic chloride inclusion complex for later use.

[0051] 0.1 g of nano zinc oxide was ultrasonically dispersed in 100 g of pure water, and 1.0 g of 3-aminopropyltriethoxysilane was added. The mixture was stirred for 2 h to obtain a functionalized nano zinc oxide suspension aqueous solution with amino groups on the surface.

[0052] (2) A cyclohexane solution of 10g of cyclodextrin-pyromellitic acid chloride inclusion complex was uniformly coated onto one surface of the pre-fabricated reverse osmosis membrane (surface area 0.1m²). 2 Let it stand for 30 seconds, then use a pressure roller to remove excess solution from the surface;

[0053] A 10g aqueous solution of functionalized nano zinc oxide with amino groups on the surface was uniformly coated onto the surface of the membrane containing cyclodextrin-organic acyl chloride inclusion complex. After standing for 60 seconds, the excess solution on the membrane surface was poured off, and the membrane was dried in an oven at 80℃ to obtain an antibacterial and antifouling reverse osmosis membrane with a nano zinc oxide-cyclodextrin composite coating on the surface.

[0054] Example 4

[0055] A method for preparing an antibacterial and antifouling reverse osmosis membrane includes the following steps:

[0056] (1) Dissolve 1.0 g of pyromellitic chloride uniformly in 100 g of cyclohexane solution, slowly add 0.4 g of cyclodextrin, sonicate for 1 h to mix evenly, and let stand to obtain a cyclohexane solution of cyclodextrin-pyromellitic chloride inclusion complex for later use.

[0057] 0.1g of nano zinc oxide was ultrasonically dispersed in 100g of pure water, and 1.0g of 3-aminopropyltrimethoxysilane was added. The mixture was stirred for 2h to obtain a functionalized nano zinc oxide suspension aqueous solution with amino groups on the surface.

[0058] (2) A cyclohexane solution of 10g of cyclodextrin-pyromellitic acid chloride inclusion complex was uniformly coated onto one surface of the pre-fabricated reverse osmosis membrane (surface area 0.1m²). 2 Let it stand for 30 seconds, then use a pressure roller to remove excess solution from the surface;

[0059] A 7.5g aqueous solution of functionalized nano zinc oxide with amino groups on its surface was uniformly coated onto the surface of a cyclodextrin-organic acyl chloride inclusion complex. After standing for 60 seconds, the excess solution on the membrane surface was poured off, and the membrane was dried in an oven at 80°C to obtain an antibacterial and antifouling reverse osmosis membrane with a nano zinc oxide-cyclodextrin composite coating on its surface.

[0060] Performance testing

[0061] The reverse osmosis membranes prepared in the above embodiments and comparative examples were subjected to performance tests, including surface properties, water treatment performance, and stability.

[0062] (1) Membrane surface properties

[0063] The membrane with the coating side was rinsed with pure water for 6 hours. The static water contact angle and surface zeta potential of the membrane before and after rinsing were tested. The results are shown in Table 1.

[0064] Table 1. Surface properties of reverse osmosis membranes in the examples and comparative examples.

[0065] As shown in Table 1, the static water contact angle of the antibacterial and antifouling reverse osmosis membrane of the present invention is between 29.0° and 30.0°, and the Zeta potential value is between -10mV and -15mV. This is consistent with the hydrophilicity and charge data of antifouling reverse osmosis membrane surfaces reported in common literature, thus meeting the two necessary conditions for the antifouling performance of reverse osmosis membranes. After rinsing with pure water, the contact angle and Zeta potential value of the membrane with polyvinyl alcohol coating in Comparative Example 1 increased, indicating that the polyvinyl alcohol coating on the surface of the reverse osmosis membrane was washed away. This phenomenon will reduce or eliminate the antifouling performance of the membrane during operation. However, the contact angle and Zeta potential values ​​of the membrane with cross-linked polyvinyl alcohol coating in Comparative Example 2 and the membrane with nano-zinc oxide-cyclodextrin antibacterial and antifouling coating of the present invention did not change significantly, indicating that the coating on the membrane still exists, thus indicating that the coating has good stability.

[0066] (2) Membrane water treatment performance

[0067] Water treatment performance testing conditions: On a cross-flow testing platform, using an aqueous solution of 2000 ppm NaCl and 50 ppm hexadecyltrimethylammonium bromide as the test solution, under the conditions of 225 psi operating pressure, 25℃ temperature, and pH 6.5-7.5, the membrane permeate flow rate (m0) was tested. After continuous operation for 12 hours, the membrane permeate flow rate (m1) was tested. The membrane was then cleaned sequentially with hydrochloric acid solution (pH=2) and sodium hydroxide solution (pH=12), and the membrane permeate flow rate (m2) was tested again. The membrane's fouling resistance was assessed by calculating the flux loss rate and flux recovery rate. The less flux decline after operation, the better the fouling resistance. Flux loss rate = (1-m1 / m0)×100%, flux recovery rate = m2 / m0×100%. The results are shown in Table 2.

[0068] Table 2. Water treatment performance of reverse osmosis membranes in the examples and comparative examples.

[0069] As shown in Table 2, comparing the initial performance of each case, except for the cross-linked polyvinyl alcohol (CVA) coated reverse osmosis membrane (Comparative Example 2), the water flux of the other coated reverse osmosis membranes is between 42-45 LMH. In comparison, the water flux of the CVA coated reverse osmosis membrane is lower. This is because the network structure of CVA is dense, which has a large resistance to water molecules. In addition, sulfuric acid solution is used to adjust the pH value during the preparation of the CVA coating. Sulfuric acid is a non-volatile acid. After the membrane is dried, it may cause the local acid concentration to be too high, which will damage the surface structure, resulting in damage to the desalination layer of the membrane and affecting the water production performance of the reverse osmosis membrane.

[0070] A detailed comparison of the flux loss rate and flux recovery rate after cleaning of the membranes after 12 hours of operation revealed that, except for the polyvinyl alcohol-coated reverse osmosis membrane (Comparative Example 1), the flux loss rate of other coated reverse osmosis membranes after 12 hours of operation was less than 11.5%, and the flux recovery rate after cleaning was higher than 93%. The polyvinyl alcohol coating is washed away during operation, resulting in poor fouling resistance. Furthermore, the flux loss rate and flux recovery rate after cleaning of the nano-zinc oxide-cyclodextrin antibacterial and antifouling coating of this invention are higher than those of traditional antifouling coatings (polyvinyl alcohol-based coatings), further demonstrating that the reverse osmosis membrane with the nano-zinc oxide-cyclodextrin antibacterial and antifouling coating of this invention has better antifouling effects.

[0071] While traditional cross-linked polyvinyl alcohol coatings possess excellent stability, they significantly reduce the water flux of reverse osmosis membranes after application, negatively impacting membrane performance. In contrast, the nano-zinc oxide-cyclodextrin antifouling coating of this invention has minimal impact on reverse osmosis membrane water flux. This is because cyclodextrin molecules possess a hollow frustum-shaped three-dimensional structure with an inner hydrophobic cavity and an outer hydrophilic edge. This unique structure exhibits minimal resistance to water molecules during separation, thus reducing the negative impact on reverse osmosis membrane water flux. Furthermore, the larger spacing between the nano-zinc oxide particles also mitigates resistance during water flow.

[0072] (3) Membrane stability study

[0073] The antibacterial and antifouling reverse osmosis membrane with a nano-zinc oxide-cyclodextrin coating from Example 1 was immersed in a 4 wt% sodium hydroxide aqueous solution for 150 h, and the microstructure of the coating on the membrane surface before and after alkaline treatment was observed. The results are shown below. Figure 2 ,Depend on Figure 2 The comparison revealed that the nano-zinc oxide-cyclodextrin antibacterial and antifouling coating remained on the membrane surface before and after alkaline immersion treatment, and the morphology of the membrane surface did not change significantly. This proves that the antibacterial and antifouling reverse osmosis membrane obtained by the method of the present invention has good stability.

[0074] (4) Antibacterial performance evaluation

[0075] The pre-fabricated reverse osmosis membrane, the cross-linked PVA-coated membrane (Comparative Example 2), and the reverse osmosis membrane of Example 1 were continuously run in E. coli solution for 120 hours. The membranes were then removed, rinsed with 100 mL of pure water, and the rinsing solution was mixed into agar for incubation. The number of colonies in the culture dish was observed to determine the antibacterial performance of the membranes. Results are as follows: Figure 3 As shown, according to Figure 3 The phenomenon observed shows that, compared to pre-fabricated RO membranes and cross-linked PVA-coated RO membranes, the surface rinsing solution of the antibacterial and antifouling reverse osmosis membrane with nano-zinc oxide-cyclodextrin coating of the present invention exhibits no colonies. This indicates that the reverse osmosis membrane prepared by the present invention has excellent antibacterial properties. This is because nano-zinc oxide slowly releases zinc ions, which have bactericidal functions.

[0076] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the technical solution and inventive concept of the present invention, should be covered within the scope of protection of the present invention.

Claims

1. A method for preparing an antibacterial and antifouling reverse osmosis membrane, characterized in that, Includes the following steps: (1) Dissolve the polyacryl chloride group organic compound uniformly in an organic solvent, then add cyclodextrin, and sonicate to obtain a cyclodextrin-organic acryl chloride inclusion complex solution; Antibacterial nanoparticles were dispersed in water, and then an aminosilane coupling agent was added. The mixture was stirred and dispersed to obtain a suspension of functionalized antibacterial nanoparticles with amino groups on the surface. The organic compound with the polyacryl chloride group is selected from one of pyromellitic tricarboxylate chloride and phthaloyl chloride; The antibacterial nanoparticles are selected from nano-zinc oxide; the organic solvent is cyclohexane. The aminosilane coupling agent is selected from one or more of 3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, 3-aminopropylmethyldimethoxysilane, N-2-aminoethyl-3-aminopropyltrimethoxysilane, and 3-diethylenetriaminopropyltrimethoxysilane. The mass ratio of the polyacrylamide chloride group organic compound, the cyclodextrin, and the organic solvent is 0.1-1.5:0.05-0.5:100; The mass ratio of the antibacterial nanoparticles, the aminosilane coupling agent, and water is 0.02-0.3:0.5-4:

100. The mass ratio of the polyacrylamide chloride group organic compound to the aminosilane coupling agent is 0.1-1.5:0.5-4; (2) The cyclodextrin-organic acyl chloride inclusion complex solution is uniformly coated onto one surface of the pre-made reverse osmosis membrane. After standing, the excess solution on the surface is removed. The functionalized antibacterial nanoparticle suspension with amino groups on the surface of the cyclodextrin-organic acyl chloride inclusion complex is superimposed and coated. After standing, the excess solution on the surface is removed. After thermal drying, the antibacterial and antifouling reverse osmosis membrane is obtained.

2. The method for preparing an antibacterial and antifouling reverse osmosis membrane according to claim 1, characterized in that, The prefabricated reverse osmosis membrane is a polyamide reverse osmosis membrane with a flux of 45 LMH-80 LMH.

3. The method for preparing an antibacterial and antifouling reverse osmosis membrane according to claim 1, characterized in that, The ultrasonic treatment time is at least 0.5 hours.

4. The method for preparing an antibacterial and antifouling reverse osmosis membrane according to claim 1, characterized in that, The stirring and dispersion time is 1-3 hours.

5. The method for preparing an antibacterial and antifouling reverse osmosis membrane according to claim 1, characterized in that, The coating amount of the cyclodextrin-organic acyl chloride inclusion complex solution on the surface of the pre-fabricated reverse osmosis membrane is 50-200 g / m. 2 The coating amount of the amino-functionalized antibacterial nanoparticle suspension on the surface containing cyclodextrin-organic acyl chloride inclusion complex is 50-100 g / m². 2 The settling time is at least 30 seconds; the temperature of the thermal drying is 60-80℃.

6. The antibacterial and antifouling reverse osmosis membrane obtained by any one of the preparation methods according to claims 1-5.

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