Method for preparing reverse osmosis membrane and reverse osmosis membrane prepared thereby

Abstract

The invention relates to a preparation method of a reverse osmosis membrane and the reverse osmosis membrane prepared thereby. The preparation method comprises the following steps: forming a porous polymer supporting layer base membrane; pretreating the porous polymer support layer base membrane by using an aqueous solution containing a silane coupling agent; contacting the pretreated porous polymer support layer base membrane with a solution containing a catalyst and a substance capable of forming an artificial water channel so as to form the artificial water channel through self-assembly; sequentially contacting a pretreated porous polymer supporting layer base membrane with an amine monomer-containing water phase solution and an acyl chloride monomer-containing oil phase solution to form a polyamide functional layer; and performing post-treatment to obtain the reverse osmosis membrane. The reverse osmosis membrane with high flux and high desalination rate can be prepared by the method, and the prepared reverse osmosis membrane can effectively reduce the operation pressure in the operation process, thereby achieving the purposes of energy conservation and consumption reduction.

Description

Technical Field

[0001] The invention relates to the technical field of reverse osmosis membranes, in particular to a reverse osmosis membrane with an artificial water channel and a preparation method thereof. Background Art

[0002] As one of the key technologies to solve the current global water resource problems, reverse osmosis technology has received unprecedented attention worldwide. Although reverse osmosis membranes have been widely used in the fields of electricity, metallurgy, petrochemicals, medicine, food, municipal engineering, sewage reuse and seawater desalination, there is still a prominent contradiction in meeting the huge demand for reverse osmosis membrane applications and the limitations of existing desalination technologies. Among them, improving the comprehensive performance of reverse osmosis membranes with water flux and desalination rate as the core is an enduring research topic.

[0003] Aquaporin is a natural protein widely found in organisms. It forms "pores" on the cell membrane, which can control the flow of water in and out of the cell and exclude all ions. In recent years, many research institutions and market players have launched research on the introduction of aquaporin into the manufacturing technology of reverse osmosis membranes. Natural aquaporin is widely used in reverse osmosis membranes.

[0004] Patent document 1 (CN108176241B) provides a composite nanofiltration membrane containing water channel protein and a preparation method thereof. The preparation method comprises: step S1, arranging water channel protein vesicles and polyamine aqueous phase monomer solution on the surface of a porous support layer to obtain a surface-treated porous support layer, wherein the polyamine aqueous phase monomer solution comprises polyamine, surfactant, acid acceptor and water; step S2, performing a second surface treatment on the surface-treated porous support layer using a polyacyl chloride oil phase monomer solution to obtain a composite nanofiltration preliminary membrane; and step S3, drying the composite nanofiltration preliminary membrane to obtain a composite nanofiltration membrane, wherein the composite nanofiltration membrane comprises a porous support layer and a polyamide layer formed by polymerization, wherein the water channel protein vesicles are dispersed in the polyamide layer, which can not only protect the activity of the water channel protein, but also ensure the strength of the composite nanofiltration membrane, significantly improve the water flux of the membrane, and enhance the anti-pollution ability of the membrane.

[0005] Patent document 2 (CN103463997B) discloses a method for preparing a composite membrane containing water channel protein, wherein dopamine is self-polymerized on the surface of a basement membrane, and the basement membrane with polydopamine attached to the surface reacts with the amine group of a phosphatidylethanolamine membrane containing water channel protein, thereby preparing a composite membrane. This patented technology belongs to the field of nanofiltration membrane technology.

[0006] Patent document 3 (CN103721572B) discloses a method for preparing a phospholipid biomimetic membrane containing water channel protein, which utilizes layer-by-layer assembly to prepare a composite membrane with an electronegative surface, and then uses electrostatic binding to spread a positively charged phospholipid vesicle solution encapsulating water channel protein on the composite membrane to form a phospholipid bilayer membrane. This patented technology belongs to the field of nanofiltration membrane technology.

[0007] Patent document 4 (CN104144737B) discloses a thin film composite membrane based on water channel protein, in which a thin selective layer of natural amphiphilic vesicles is supported by a microporous substrate, wherein the amphiphilic substance is selected from block copolymers, including triblock copolymers of hydrophile-hydrophobe-hydrophile ABA or ABC type or diblock copolymers of hydrophile-hydrophobe AB type.

[0008] Patent document 5 (CN106731908A) discloses a composite reverse osmosis membrane containing aquaporin and a preparation method thereof. The preparation method of the reverse osmosis membrane comprises modifying the surface of a polysulfone support membrane, grafting amino functional groups thereon, and allowing the amino groups to participate in the interfacial polymerization reaction of polyamide, so that the connection between the polysulfone support layer and the polyamide active layer is a chemical bond force, thereby enhancing the bonding force between the two, and thereby effectively extending the life of the composite reverse osmosis membrane.

[0009] Patent document 6 (CN106928324A) discloses a method for improving the expression activity of aquaporin in vesicles, the first step of which includes the phosphorylation of aquaporin and the preparation of a phospholipid vesicle system solution, and the second step is the introduction of phosphorylated aquaporin. The phosphorylation of aquaporin improves the expression activity of aquaporin, and then the phosphorylated aquaporin is embedded in a vesicle and applied to a reverse osmosis membrane. When the water flux and desalination rate are at the same level, the ratio of the aquaporin used to the vesicle is greatly reduced.

[0010] Patent document 7 (CN107474119B) discloses an antibacterial aquaporin vesicle, and uses the antibacterial aquaporin vesicle to prepare an antibacterial aquaporin reverse osmosis membrane. The antibacterial aquaporin vesicle of the invention is prepared by embedding aquaporin with quaternized ABA or AB amphiphilic block copolymers, and then the antibacterial aquaporin vesicle is directly added to the reverse osmosis membrane, which does not destroy the surface structure of the polyamide functional layer and simplifies the preparation process of the aquaporin reverse osmosis membrane with antibacterial function.

[0011] Patent document 8 (CN108602025B) discloses an RO membrane or FO membrane having a high water permeability and salt blocking performance, comprising a covering layer composed of a phospholipid bilayer membrane formed on the surface of a porous membrane body, wherein the RO membrane or FO membrane has a porous membrane with a pore size of 5nm to 50nm and a covering layer composed of a phospholipid bilayer formed on the surface of the aforementioned porous membrane, wherein the phospholipid bilayer contains phospholipids, amphotericin B and ergosterol, wherein amphotericin B is contained as a channel substance.

[0012] Patent document 9 (CN108697984B) discloses a self-assembled nanostructure formed between a transmembrane protein such as aquaporin and polyalkyleneimine, and a separation membrane comprising the nanostructure.

[0013] Patent document 10 (CN110382094A) discloses a selective permeable membrane, which comprises a selective permeable support membrane and a lipid membrane formed on the surface of the support membrane and containing a channel substance, wherein the support membrane has a flow rate of 20 L / (m 2 h) and a permeation flux of 1% to 20%.

[0014] Patent document 11 (CN111545084A) discloses a method for preparing a composite nanofiltration membrane containing water channel protein, the preparation method comprising: S1, placing water channel protein vesicles and polyamine aqueous phase monomer solution on the surface of a porous support layer to obtain a surface-treated porous support layer, the polyamine aqueous phase monomer solution comprising polyamine, surfactant, acid acceptor and water; S2: preparing a phosphate buffer solution with a pH value of 5.5-8; S3: dissolving tannic acid and polyetheramine in the phosphate buffer solution respectively to prepare a tannic acid solution and a polyetheramine solution with a concentration of 0.1-0.5 g / L. In this invention, tannic acid and polyetheramine are alternately deposited on a porous polymer original membrane to obtain a nanofiltration membrane with a stable selective layer structure, which is beneficial to improving the stability of the membrane. Moreover, the polyethylene glycol segment in the polyetheramine can reduce the adhesion of proteins and improve the anti-pollution performance of the membrane.

[0015] Patent document 12 (CN112058097B) discloses a method for preparing a forward osmosis membrane material, which is composed of a four-layer structure, including a basement membrane, a dopamine cushion layer, a phospholipid bilayer containing water channel protein, and a polymer protective layer. The forward osmosis membrane prepared by this invention has a dense non-porous structure, efficient interception, high mechanical strength and acid and alkali resistance, and can achieve a removal effect of more than 99% of monovalent ions; it has good stability, a high water flux recovery rate after the osmotic membrane is cleaned, strong anti-pollution ability, and can effectively alleviate concentration polarization and has a long operating time. Water channel protein has a single water molecule selective permeability, and its water molecule transmission rate exceeds any current nanoporous material, which can ensure a substantial increase in the water flux of the composite membrane.

[0016] Patent document 13 (CN113543871A) discloses a method for manufacturing a membrane containing proteoliposomes having protein water channels. The method may include: providing a porous substrate, depositing a solution containing proteoliposomes on the porous substrate, and then contacting the porous substrate with an aqueous monomer solution and an organic monomer solution to form a selective layer on the porous substrate in which the proteoliposomes are embedded. The method may include: depositing an aqueous monomer solution, then depositing a solution containing proteoliposomes, and then depositing an organic monomer solution to form a selective layer.

[0017] The application of natural water channel proteins in reverse osmosis membranes has the following problems: first, the source is very rare. Although proteins with channel functions are widely present in nature, so far, 13 different types of channel proteins have been found in mammals alone, but proteins with channel functions only exist in specific parts of the animal body, and the output is extremely small; second, it is difficult to separate and purify, because natural water channel proteins exist in animals, so it is extremely difficult to collect, separate, purify, and enrich, and it faces great technical challenges; third, the material cost is high. Due to the low output and difficulty in purification and separation, the material cost of natural water channel proteins is extremely high; fourth, the stability is poor, it is easy to deteriorate and inactivate, it is extremely sensitive to environmental changes, and it is difficult to adapt to the complex and changeable water quality environment; fifth, it is difficult to synthesize artificially. Since the mechanism of forming natural water channel proteins is still unclear, it is also extremely difficult to synthesize artificially. In summary, natural water channel protein technology is difficult to be applied to reverse osmosis membrane technology on a large scale.

[0018] The counterpart of natural water channel proteins is artificial water channels, which are still in the initial stage of research. The application of artificial water channel proteins in reverse osmosis membranes is relatively rare. Artificial water channel technology is a technology that uses simpler technical means to synthesize substances with functions similar to those of natural water channel proteins. Synthetic biomimetic methods provide us with the possibility of constructing artificial single molecule or supramolecular structures that can mimic biological functions and have the characteristics of simple structure, easy synthesis, relatively low cost, high stability, good adjustability, and adjustable compatibility with membrane substrates.

[0019] Patent document 14 (CN112717715A) discloses a polyvinylamine membrane with nano-hydrophilic channels and its preparation and application. The preparation process includes: first, preparing polyvinylamine by free radical polymerization-hydrolysis of N-vinylformamide, reacting a small amount of amino groups in the polyvinylamine with an acyl chloride compound with a hydrophobic comb-like side chain, and after the reaction, coating it on a polyacrylonitrile ultrafiltration membrane by a solution coating method, and letting it stand for microphase separation to prepare a pervaporation composite membrane.

[0020] Patent document 15 (CN113600036A) discloses a method for preparing a high-flux composite nanofiber membrane with an artificial water channel, in which single-walled carbon nanotubes are used as artificial water channels and loaded onto the surface of an electrospun nanofiber membrane substrate by electrostatic spraying to prepare a composite nanofiber membrane with high permeation flux. The prepared composite nanofiber membrane has high permeation flux and good biodegradability.

[0021] Patent document 16 (CN114728241A) discloses a composite bionic membrane having artificial water channels, wherein the artificial water channel protein used is formed by a supramolecular aggregate composed of a self-organized lamellar phase containing artificial water channels of the imidazole tetrad type.

[0022] Patent document 17 (CN112295411B) discloses a modified polyamide membrane and a preparation method thereof, wherein the preparation method comprises the following steps: (1) coating a solution containing a pyrimidine or purine compound on the surface of a nascent polyamide membrane; (2) heating the polyamide membrane coated with the pyrimidine or purine compound to complete the reaction; (3) coating the polyamide membrane after the reaction with a solution of purine or pyrimidine compound to complete base pairing, thereby obtaining a polyamide membrane modified with pyrimidine and purine compounds. The method is simple in process and easy to operate, and the obtained polyamide membrane not only has a better salt rejection rate and flux, but also has improved deboronization performance and chlorine resistance. Summary of the invention

[0023] Problem that the invention aims to solve

[0024] The purpose of the present invention is to solve the above problems existing in the prior art and to provide a method for preparing a reverse osmosis membrane and a reverse osmosis membrane prepared thereby. The method effectively solves the problems of rare production of natural water channel proteins, difficulty in collection, high cost, poor stability, and difficulty in large-scale application in reverse osmosis membrane preparation technology by constructing artificial water channels.

[0025] Solutions for solving problems

[0026] In order to achieve the above objectives, the inventors of the present invention conducted intensive research and found that by pretreating the porous polymer support base membrane with a silane coupling agent, the artificial water channel material to be introduced later can be more efficiently immobilized on the surface of the base membrane. By using a catalyst, the material that can form artificial water channels can form artificial water channels on the surface of the base membrane through self-assembly, and then an ultra-thin functional layer is prepared through interfacial polymerization reaction. A reverse osmosis membrane with high flux and high desalination rate can be prepared. The prepared reverse osmosis membrane can effectively reduce the operating pressure during its operation, thereby achieving the purpose of energy saving and consumption reduction.

[0027] One aspect of the present invention relates to a method for preparing a reverse osmosis membrane, which comprises the following steps:

[0028] (1) preparing a polymer solution as a casting solution, applying the casting solution to a non-woven fabric, and then solidifying the casting solution in a coagulation bath to form a film, thereby forming a porous polymer support layer base film;

[0029] (2) pretreating the porous polymer support layer base membrane obtained in (1) using an aqueous solution containing a silane coupling agent;

[0030] (3) contacting the pretreated porous polymer support layer base membrane obtained in (2) with a solution containing a catalyst and a substance capable of forming an artificial water channel to form an artificial water channel by self-assembly;

[0031] (4) contacting the pretreated porous polymer support layer base membrane having artificial water channels obtained in (3) with an aqueous solution containing an amine monomer and an oil solution containing an acyl chloride monomer in sequence, thereby forming a polyamide functional layer;

[0032] (5) After post-treatment, a reverse osmosis membrane is obtained.

[0033] In the preparation method of the present invention, the polymer is one or more of bisphenol A type polysulfone, polyethersulfone, polyarylsulfone, polynaphthylidene ether sulfone ketone, polyaryl ether sulfone ketone, naphthalene biphenyl polyaryl ether nitrile ketone, polyacrylonitrile and sulfonated polyethersulfone.

[0034] The preparation method of the present invention, wherein the silane coupling agent is one or more of 3-aminopropyltriethoxysilane, 3-aminopropyltrimethoxysilane, 3-glycidyloxypropyltrimethoxysilane, N-(2-aminoethyl)-3-aminopropylmethyldimethoxysilane, N-(2-aminoethyl)-3-aminopropyltrimethoxysilane, N-(2-aminoethyl)-3-aminopropyltriethoxysilane, vinyltriethoxysilane, vinyltrimethoxysilane, vinyltri(2-methoxyethoxy)silane, and 3-aminopropylmethyldiethoxysilane.

[0035] In the preparation method of the present invention, the substance capable of forming an artificial water channel has one of the following molecular structures I, II and III:

[0036]

[0037] Wherein R is a straight or branched alkyl group having 1 to 8 carbon atoms, and X is O or S.

[0038] In the preparation method of the present invention, the catalyst is one or more of selenium dioxide, selenium disulfide, potassium permanganate and potassium dichromate.

[0039] The preparation method of the present invention, wherein the amine monomer is o-phenylenediamine, m-phenylenediamine, p-phenylenediamine, s-phenylenediamine, polyetheramine, 3-fluoroaniline, 3-chloroaniline, aminopiperazine, 2,3-diaminopyridine, 2,6-diaminopyridine, 2,5-diaminobenzenesulfonic acid, N-phenyl-p-phenylenediamine, 1,4-phenylenediamine, m-phenylenediamine, 2,4-diaminotoluene, 2,5-diaminotoluene, 2,6-diaminotoluene, 2,4-diaminoanisole, 3,4'-diaminoanisole, One or more of aminodiphenyl ether, 1,2-propylenediamine, 1,3-propylenediamine, diisobutylamine, 1,2-cyclohexanediamine, n-hexylamine, heptylamine, cycloheptylamine, 1,8-octanediamine, decylamine, dodecylamine, N-ethylethylenediamine, N-butylethylenediamine, 4,5-dimethyl-1,2-phenylenediamine, 1,5-diaminonaphthalene, N,N-diethyl-p-phenylenediamine, 2-hydroxyethylpropylamine, 1,3-diamino-2-propanol and 3,3',5,5'-tetramethylbenzidine.

[0040] The preparation method of the present invention, wherein the acyl chloride monomer is trimesoyl chloride, pyromellitoyl chloride, terephthaloyl chloride, isophthaloyl chloride, o-chlorobenzoyl chloride, oxalyl chloride, 3-bromopropionyl chloride, undecanoyl chloride, dodecanoyl chloride, n-valeryl chloride, 3-fluorobenzoyl chloride, 4-methoxybenzoyl chloride, 4-phenylbenzoyl chloride, p-fluorobenzoyl chloride, isovaleryl chloride, succinoyl chloride, 1,7-heptanedioyl chloride, ethyl malonate chloride, m-methylbenzoyl chloride, 2-methoxybenzoyl chloride, 4-methylbenzoyl chloride, One or more of oxybenzoyl chloride, 4-phenylbenzoyl chloride, 3,4-dimethoxybenzoyl chloride, cyclopentylcarbonyl chloride, cyclopropylcarbonyl chloride, heptanoyl chloride, 3-phenylpropionyl chloride, o-fluorobenzenesulfonyl chloride, p-ethylbenzoyl chloride, perfluorooctanesulfonyl chloride, 2,4,6-trichlorobenzoyl chloride, 4-bromo-2-fluorobenzoyl chloride, 3,5-difluorobenzoyl chloride, 2,5-difluorobenzoyl chloride, 3,4-dichlorobenzoyl chloride, 4-n-propylbenzoyl chloride, n-butyryl chloride and 2-nitrobenzoyl chloride.

[0041] Another aspect of the present invention relates to a reverse osmosis membrane, which comprises a porous polymer support layer base membrane and a polyamide functional layer in sequence, wherein the porous polymer support layer base membrane comprises a polymer porous support layer formed on a non-woven fabric layer, and is characterized in that an artificial water channel is provided between the porous polymer support layer base membrane and the polyamide functional layer, and the artificial water channel is formed by self-assembly of substances that can form artificial water channels.

[0042] The reverse osmosis membrane of the present invention, wherein the substance capable of forming an artificial water channel has one of the following molecular structures I, II and III:

[0043]

[0044]

[0045] Wherein R is a straight or branched alkyl group having 1 to 8 carbon atoms, and X is O or S.

[0046] Effects of the Invention

[0047] The reverse osmosis membrane preparation method provided by the present invention effectively solves the problems of rare production, difficulty in collection, high cost, poor stability, and difficulty in large-scale application of natural water channel protein in reverse osmosis membrane preparation technology by constructing artificial water channels. The prepared reverse osmosis membrane has high flux, high desalination rate and can effectively reduce the operating pressure during its operation, thereby achieving the purpose of energy saving and consumption reduction. BRIEF DESCRIPTION OF THE DRAWINGS

[0048] Figure 1Schematic diagrams of artificial water channels formed by the method of the present invention are shown, the left figure is a schematic diagram of a single water channel, and the right figure is a schematic diagram of multiple water channels (also called water cluster channels). DETAILED DESCRIPTION

[0049] Various exemplary embodiments, features and aspects of the present invention will be described in detail below. The word "exemplary" used here means "used as an example, embodiment or illustrative". Any embodiment described here as "exemplary" is not necessarily interpreted as being superior or better than other embodiments.

[0050] In addition, in order to better illustrate the present invention, numerous specific details are provided in the following specific embodiments. It should be understood by those skilled in the art that the present invention can be implemented without certain specific details. In other examples, methods, means, equipment and steps well known to those skilled in the art are not described in detail in order to highlight the subject matter of the present invention.

[0051] Unless otherwise stated, the units used in this specification are all international standard units, and the numerical values ​​and numerical ranges appearing in the present invention should be understood to include the inevitable systematic errors in industrial production.

[0052] In this specification, the word "may" means both performing a certain process and not performing a certain process.

[0053] In this specification, the references to "some specific / preferred embodiments", "other specific / preferred embodiments", "embodiments", etc., mean that the specific elements (e.g., features, structures, properties and / or characteristics) described in connection with the embodiments are included in at least one embodiment described herein, and may or may not exist in other embodiments. In addition, it should be understood that the elements may be combined in various embodiments in any suitable manner.

[0054] In this specification, the numerical range expressed using "a numerical value A to a numerical value B" means a range including the endpoints numerical values ​​A and B.

[0055] In this specification, when "normal temperature" or "room temperature" is used, the temperature may be 10-40°C.

[0056] The invention relates to a method for preparing a reverse osmosis membrane, which comprises the following steps:.

[0057] (1) preparing a polymer solution as a casting solution, applying the casting solution to a non-woven fabric, and then solidifying the casting solution in a coagulation bath to form a film, thereby forming a porous polymer support layer base film;

[0058] (2) pretreating the porous polymer support layer base membrane obtained in (1) using an aqueous solution containing a silane coupling agent;

[0059] (3) contacting the pretreated porous polymer support layer base membrane obtained in (2) with a solution containing a catalyst and a substance capable of forming an artificial water channel to form an artificial water channel by self-assembly;

[0060] (4) contacting the pretreated porous polymer support layer base membrane having artificial water channels obtained in (3) with an aqueous solution containing an amine monomer and an oil solution containing an acyl chloride monomer in sequence, thereby forming a polyamide functional layer;

[0061] (5) After post-treatment, a reverse osmosis membrane is obtained.

[0062] The technical concept of the present invention is to use a silane coupling agent to pretreat the porous polymer support base membrane so that the artificial water channel material to be introduced later can be more efficiently fixed on the surface of the base membrane. By using a catalyst, the material that can form artificial water channels forms artificial water channels on the surface of the base membrane through self-assembly, and then an ultra-thin functional layer is prepared through interfacial polymerization reaction. A reverse osmosis membrane with high flux and high desalination rate can be prepared. The prepared reverse osmosis membrane can effectively reduce the operating pressure during its operation, thereby achieving the purpose of energy saving and consumption reduction.

[0063] In the preparation method of the present invention, the polymer is one or more of bisphenol A type polysulfone, polyethersulfone, polyarylsulfone, polynaphthylidene ether sulfone ketone, polyaryl ether sulfone ketone, naphthalene biphenyl polyaryl ether nitrile ketone, polyacrylonitrile and sulfonated polyethersulfone.

[0064] Preferably, based on the total weight of the polymer solution, the concentration of the polymer is 15wt% to 35wt%, more preferably, the concentration of the polymer is 15wt% to 25wt%; if the concentration of the polymer is lower than 15wt%, the pore size of the prepared membrane is larger, the pure water flux is higher, and the mechanical strength is lower; if the concentration of the polymer is higher than 35wt%, the pore size of the prepared membrane is smaller, and the pure water flux is lower. Both low and high polymer concentrations are not conducive to the performance of the membrane.

[0065] Preferably, the polymer is added to the solvent and stirred until the polymer is completely dissolved to form a homogeneous solution, and the solution temperature is set to 120° C. to 180° C. After the polymer is completely dissolved, the polymer solution is placed in a vacuum drying oven for degassing and kept warm at 25° C. Preferably, the solvent used is one or more of N,N-dimethylformamide (DMF), N,N-dimethylacetamide (DMAC), and N-methyl-2-pyrrolidone.

[0066] The polymer solution is coated onto the non-woven fabric as a casting solution, and a porous polymer support layer base membrane is prepared through three steps of immersion precipitation phase conversion in a coagulation bath, washing and heat treatment.

[0067] Preferably, the coagulation bath is pure water. There is no special limitation on the material of the non-woven fabric, which may be polyester (PET), polypropylene (PP), acrylic (PAN) and polyvinyl chloride (PVC), etc. The coagulation bath temperature is, for example, 13°C, the washing water temperature is, for example, 25°C, and the heat treatment temperature is, for example, 80°C.

[0068] Preferably, the average pore size of the prepared porous polymer support layer base membrane is 5 to 30 nm, more preferably 8 to 15 nm, and the preferred pore ratio is 5% to 20%, more preferably 8% to 10%.

[0069] In the preparation method of the present invention, the silane coupling agent is one or more of 3-aminopropyltriethoxysilane, 3-aminopropyltrimethoxysilane, 3-glycidyloxypropyltrimethoxysilane, N-(2-aminoethyl)-3-aminopropylmethyldimethoxysilane, N-(2-aminoethyl)-3-aminopropyltrimethoxysilane, N-(2-aminoethyl)-3-aminopropyltriethoxysilane, vinyltriethoxysilane, vinyltrimethoxysilane, vinyltri(2-methoxyethoxy)silane, and 3-aminopropylmethyldiethoxysilane.

[0070] Preferably, based on the total weight of the aqueous solution containing the silane coupling agent, the concentration of the silane coupling agent is 0.01wt% to 5wt%, more preferably 0.5wt% to 1wt%. There is no particular restriction on the time for pretreatment with the aqueous solution containing the silane coupling agent, which can be 5s to 10min, preferably 15s to 30s. After the pretreatment, the solution is rinsed with deionized water for standby use.

[0071] In the preparation method of the present invention, the substance capable of forming an artificial water channel has one of the following molecular structures I, II and III:

[0072]

[0073]

[0074] Wherein R is a straight or branched alkyl group having 1 to 8 carbon atoms, and X is O or S.

[0075] Preferably, R is a straight-chain alkyl group having 1 to 8 carbon atoms, and more preferably, R is butyl, pentyl, hexyl, heptyl or octyl.

[0076] In the above molecular structures I, II, and III, R is a hydrophobic group in the molecule, and the middle part is a urea group (when X is O) or a thiourea group (when X is S) structure. The urea group or the thiourea group mainly plays the role of a molecular skeleton, and the -NH on the urea group between the molecules is self-assembled through hydrogen bonding. The third part is a polyol structure with 2 or 3 hydroxyl groups, which are connected at the head by hydrogen bonding to form a single water channel or multiple water (also known as water cluster) channels.

[0077] Molecular structure I self-assembles through hydrogen bonds to form the following structure:

[0078]

[0079] Molecular structure II is self-assembled through hydrogen bonding to form the following structure:

[0080]

[0081] The molecular structure III is self-assembled through hydrogen bonding to form the following structure:

[0082]

[0083] In the above molecular structures I, II, and III, the structural part formed by hydrogen bonds between alcoholic hydroxyl groups is the water molecule channel, which is divided into single water channel or multi-water (also known as water cluster) channel according to the width of the water molecule transmission path, such as Figure 1 As shown, the left figure is a schematic diagram of a single water channel, and the right figure is a schematic diagram of multiple water channels (also known as water cluster channels).

[0084] The pretreated porous polymer support layer base membrane is contacted with a solution containing a catalyst and a substance capable of forming an artificial water channel to form the artificial water channel by self-assembly.

[0085] Preferably, the pretreated porous polymer support layer base membrane is immersed in a solution containing a catalyst and a substance that can form an artificial water channel. There is no particular restriction on the immersion time and the solution temperature, which can be 5s to 24h. The solution temperature can be 10 to 40°C, preferably 15°C to 30°C.

[0086] The solution may further contain a solvent. Preferably, the solvent is one or more of water, methanol, ethanol, chloroform and carbon tetrachloride.

[0087] In the preparation method of the present invention, the catalyst is one or more of selenium dioxide, selenium disulfide, potassium permanganate, and potassium dichromate. The catalyst is used to oxidize the methyl and methylene groups in the molecular structures I, II, and III and convert them into aldehyde or carboxyl groups with higher activity, thereby reacting with the silane coupling agent.

[0088] Preferably, the concentration of the substance capable of forming an artificial water channel is 0.01 mol / L to 0.5 mol / L, and more preferably, the concentration is 0.05 mol / L to 0.2 mol / L.

[0089] Preferably, the solvent is evaporated by reduced pressure evaporation, the pressure range is 0.1 to 0.5 standard atmospheres, i.e., 0.01 MPa to 0.05 MPa, while maintaining the temperature at 30°C to 40°C, and the evaporation time is 0.5h to 12h. Under this condition, a material that can form an artificial water channel is deposited, and after the evaporation is completed, it is washed with deionized water for later use.

[0090] In the preparation method of the present invention, the amine monomer is o-phenylenediamine, m-phenylenediamine, p-phenylenediamine, s-phenylenediamine, polyetheramine, 3-fluoroaniline, 3-chloroaniline, aminopiperazine, 2,3-diaminopyridine, 2,6-diaminopyridine, 2,5-diaminobenzenesulfonic acid, N-phenyl-p-phenylenediamine, 1,4-phenylenediamine, m-phenylenediamine, 2,4-diaminotoluene, 2,5-diaminotoluene, 2,6-diaminotoluene, 2,4-diaminoanisole, 3,4'-diaminoanisole, One or more of aminodiphenyl ether, 1,2-propylenediamine, 1,3-propylenediamine, diisobutylamine, 1,2-cyclohexanediamine, n-hexylamine, heptylamine, cycloheptylamine, 1,8-octanediamine, decylamine, dodecylamine, N-ethylethylenediamine, N-butylethylenediamine, 4,5-dimethyl-1,2-phenylenediamine, 1,5-diaminonaphthalene, N,N-diethyl-p-phenylenediamine, 2-hydroxyethylpropylamine, 1,3-diamino-2-propanol and 3,3',5,5'-tetramethylbenzidine.

[0091] In the preparation method of the present invention, the acyl chloride monomer is trimesoyl chloride, pyromellitoyl chloride, terephthaloyl chloride, isophthaloyl chloride, o-chlorobenzoyl chloride, oxalyl chloride, 3-bromopropionyl chloride, undecanoyl chloride, dodecanoyl chloride, n-valeryl chloride, 3-fluorobenzoyl chloride, 4-methoxybenzoyl chloride, 4-phenylbenzoyl chloride, p-fluorobenzoyl chloride, isovaleryl chloride, succinoyl chloride, 1,7-heptanedioyl chloride, ethyl malonate chloride, m-methylbenzoyl chloride, 2-methoxybenzoyl chloride, 4-methylbenzoyl chloride, One or more of oxybenzoyl chloride, 4-phenylbenzoyl chloride, 3,4-dimethoxybenzoyl chloride, cyclopentylcarbonyl chloride, cyclopropylcarbonyl chloride, heptanoyl chloride, 3-phenylpropionyl chloride, o-fluorobenzenesulfonyl chloride, p-ethylbenzoyl chloride, perfluorooctanesulfonyl chloride, 2,4,6-trichlorobenzoyl chloride, 4-bromo-2-fluorobenzoyl chloride, 3,5-difluorobenzoyl chloride, 2,5-difluorobenzoyl chloride, 3,4-dichlorobenzoyl chloride, 4-n-propylbenzoyl chloride, n-butyryl chloride and 2-nitrobenzoyl chloride.

[0092] Preferably, the pretreated porous polymer support layer base membrane with artificial water channels obtained as described above is immersed in an aqueous solution containing an amine monomer as an aqueous phase monomer for 5s to 60s, and after being taken out, the excess solution on the surface is blown away with nitrogen; then it is immersed in an oil phase solution containing an acyl chloride monomer as an oil phase monomer for 5s to 60s, and naturally dried.

[0093] Preferably, based on the total weight of the aqueous solution, the concentration of the amine monomer is 0.5 wt % to 9.0 wt %.

[0094] In the preparation method of the present invention, preferably, an acid absorber (also called pH adjuster) is added to the aqueous phase solution to adjust the pH value of the solution to a range of 8 to 10. More preferably, the pH adjuster is a combination of camphorsulfonic acid / triethylamine. Based on the total weight of the aqueous phase solution, the concentration of the pH adjuster is 0.5wt%-5wt%. The pH adjuster is used to absorb excess acid generated by interfacial polymerization and promote continuous forward reaction of interfacial polymerization.

[0095] Preferably, the acyl chloride monomer is one or more of trimesoyl chloride, pyromellitoyl chloride, terephthaloyl chloride, o-chlorobenzoyl chloride and isophthaloyl chloride, and the concentration of the acyl chloride monomer is 0.01wt% to 5wt% based on the total weight of the oil phase solution. Preferably, the solvent in the oil phase solution is one or more of ethylcyclohexane, n-hexane, n-heptane, ISOPAR G and ISOPAR E.

[0096] In the preparation method of the present application, the post-treatment is preferably washing with deionized water to remove the solvent and the monomers that have not reacted completely, and then drying. There is no particular restriction on the drying temperature, which is usually 50 to 100°C; there is no particular restriction on the drying time, which is usually 5 to 60 minutes.

[0097] Preferably, a rinsing component is added to the deionized water, and the rinsing component is one or more of citric acid, sodium citrate, sodium carbonate, and sodium bicarbonate, and the concentration thereof is 0.5wt% to 20wt%, more preferably 5wt% to 10wt%, and the preferred solution temperature is 30°C to 80°C, more preferably 50°C to 70°C. There is no particular restriction on the rinsing time, and the preferred rinsing time is 5s to 10min, more preferably 30s to 2min.

[0098] The present invention also provides a reverse osmosis membrane, which comprises a porous polymer support layer base membrane and a polyamide functional layer in sequence, wherein the porous polymer support layer base membrane comprises a polymer porous support layer formed on a non-woven fabric layer, wherein an artificial water channel is provided between the porous polymer support layer base membrane and the polyamide functional layer, and the artificial water channel is formed by self-assembly of substances that can form artificial water channels.

[0099] According to the reverse osmosis membrane of the present invention, the substance capable of forming an artificial water channel has one of the following molecular structures I, II and III:

[0100]

[0101]

[0102] Wherein R is a straight or branched alkyl group having 1 to 8 carbon atoms, and X is O or S.

[0103] The descriptions of the molecular structure I, the molecular structure II, and the molecular structure III are the same as those in the above-mentioned method for producing a reverse osmosis membrane.

[0104] The reverse osmosis membrane prepared by the present invention has been significantly improved in water molecule transmission and salt retention. The artificial water channel layer embedded between the porous polymer support base membrane and the polyamide functional layer can transmit up to 2×10 8 Water molecules / second / channel, while intercepting most of the ions. Its water molecule transmission efficiency is close to that of natural aquaporin, which effectively improves the permeability selectivity of the reverse osmosis membrane.

[0105] At present, most natural water channel proteins have the disadvantages of scarce sources, difficulty in enrichment and purification, high cost, difficulty in adapting to the harsh application environment of reverse osmosis membranes, and difficulty in artificial synthesis. The material used in the present invention that can form artificial water channels has the advantages of large-scale manufacturing, low cost, controllable process, stable structure, etc., which overcomes the application disadvantages of natural water channel proteins; compared with the existing reverse osmosis membrane (referred to as RO membrane), the reverse osmosis membrane prepared by the present invention has a higher flux due to the artificial water channels contained therein, and at least ensures that the desalination rate is not lower than that of the existing reverse osmosis membrane. Therefore, the reverse osmosis membrane prepared by the present invention has the characteristics of high flux and high desalination rate, effectively reduces the operating pressure of the reverse osmosis membrane, and achieves the purpose of energy saving and consumption reduction.

[0106] Example

[0107] The embodiments of the present invention will be described in detail below in conjunction with the examples, but those skilled in the art will appreciate that the following examples are only used to illustrate the present invention and should not be considered to limit the scope of the present invention. If no specific conditions are specified in the examples, they are carried out according to normal conditions or the conditions recommended by the manufacturer. If the manufacturer is not specified for the reagents or instruments used, they are all conventional products that can be obtained commercially.

[0108] Comparative Example

[0109] Step 1: Preparation of porous polymer support layer base membrane

[0110] The polymer is dissolved in a solvent, left to stand for degassing, and then the solution is scraped onto a non-woven fabric and the solvent and polymer are phase separated in a coagulation bath to prepare a base film with a porous structure. The solvent is N,N-dimethylformamide (DMF); the polymer is: bisphenol A type polysulfone, with a content of 18wt%; the coagulation bath is pure water, the temperature is 12°C, and the non-woven fabric is made of polyester (PET).

[0111] Step 2: Preparation of reverse osmosis membrane

[0112] The base film prepared in step 1 is first immersed in an aqueous solution containing an aqueous monomer for 10 seconds, taken out and the excess solution is blown off with nitrogen; then immersed in an oil solution containing an oil monomer for 20 seconds; finally taken out, rinsed with deionized water and dried in an oven at 80°C. The aqueous monomer is: m-phenylenediamine, with a content of 4wt%, the acid absorbent is 2wt% camphorsulfonic acid / 1wt% triethylamine; the oil monomer is: trimesoyl chloride, with a content of 0.15wt%, and the solvent is ethylcyclohexane.

[0113] Step 3: Post-processing of the membrane

[0114] The membrane sheet after step 2 is immersed in a water tank containing a rinsing solution to remove excess monomers and solvents. The rinsing component is citric acid with a concentration of 8 wt %, a temperature of 70° C., and a rinsing time of 2 min.

[0115] Example 1

[0116] Step 1: Preparation of porous polymer support layer base membrane

[0117] The polymer is dissolved in a solvent, left to stand for degassing, and then the solution is scraped onto a non-woven fabric and the solvent and polymer are phase separated in a coagulation bath to prepare a base film with a porous structure. The solvent is N,N-dimethylformamide (DMF); the polymer is: bisphenol A type polysulfone, with a content of 18wt%; the coagulation bath is pure water, the temperature is 12°C, and the non-woven fabric is made of polyester (PET).

[0118] Step 2: Pretreatment of porous polymer support layer with silane coupling agent

[0119] The porous polymer support layer base membrane prepared in step 1 is pretreated with an aqueous solution containing a silane coupling agent, wherein the silane coupling agent used is 3-aminopropyltriethoxysilane with a concentration of 0.5wt%. The pretreatment is performed for 20s. After the pretreatment is completed, the base membrane is washed with deionized water for standby use.

[0120] Step 3: Self-assembly of artificial water channels on the porous polymer support layer

[0121] The porous polymer support layer base membrane completed in step 2 is immersed in a solution containing N, N'-1, 2-propanediolmethyl octyl urea artificial water channel molecules of molecular structure type I, the immersion time is 30 minutes, the solution temperature is 30°C, the solution contains 2.5g / L selenium dioxide, 0.1mol / L N, N'-1, 2-propanediolmethyl octyl urea, and the solvent is water. The solvent is evaporated by reduced pressure evaporation, the pressure is 0.02MPa, while maintaining the temperature at 35°C, the evaporation time is 5h, and the artificial water channel molecules are deposited under this condition. After evaporation, it is washed with deionized water for standby use.

[0122] Step 4: Preparation of a reverse osmosis membrane with an ultrathin functional layer by interfacial polymerization on a base membrane with artificial water channels

[0123] The base film after step 3 is first immersed in an aqueous solution containing an aqueous monomer for 10 seconds, taken out and the excess solution is blown off with nitrogen; then immersed in an oil solution containing an oil monomer for 20 seconds; finally taken out, rinsed with deionized water and dried in an oven at 80°C. The aqueous monomer is: m-phenylenediamine, with a content of 4wt%, the acid absorbent is 2% camphorsulfonic acid / 1% triethylamine; the oil monomer is: trimesoyl chloride, with a content of 0.15wt%, and the solvent is ethylcyclohexane.

[0124] Step 5: Post-processing of the membrane

[0125] The membrane sheet after step 4 is immersed in a water tank containing a rinsing solution to remove excess monomers and solvents. The rinsing component is citric acid with a concentration of 8 wt %, a temperature of 70° C., and a rinsing time of 2 min.

[0126] Example 2

[0127] Step 1 and step 2 are the same as step 1 and step 2 in Example 1.

[0128] Step 3: Self-assembly of artificial water channels on the porous polymer support layer

[0129] The porous polymer support layer base membrane completed in step 2 is immersed in a solution containing N, N'-1, 3-propanediolmethyl octyl urea artificial water channel molecules of molecular structure II, the immersion time is 30 minutes, the solution temperature is 30°C, the solution contains 2.5g / L selenium dioxide, 0.1mol / L N, N'-1, 3-propanediolmethyl octyl urea, and the solvent is water. The solvent is evaporated by reduced pressure evaporation, the pressure is 0.02MPa, while maintaining the temperature at 35°C, the evaporation time is 5h, and the artificial water channel molecules are deposited under this condition. After evaporation, it is washed with deionized water for standby use.

[0130] Step 4 and Step 5 are the same as Step 4 and Step 5 in Example 1.

[0131] Example 3

[0132] Step 1 and step 2 are the same as step 1 and step 2 in Example 1.

[0133] Step 3: Self-assembly of artificial water channels on the porous polymer support layer

[0134] The porous polymer support layer base membrane completed in step 2 is immersed in a solution containing N, N'-2, 3-bis(hydroxymethyl)ethanol octyl urea artificial water channel molecules of molecular structure III, the immersion time is 30 minutes, the solution temperature is 30°C, the solution contains 2.5g / L selenium dioxide, 0.15mol / LN, N'-2, 3-bis(hydroxymethyl)ethanol octyl urea, the solvent is an ethanol / water mixture with a volume ratio of 80 / 2, the solvent is evaporated by reduced pressure evaporation, the pressure is 0.02MPa, while maintaining the temperature at 35°C, the evaporation time is 5h, the artificial water channel molecules are deposited under this condition, and after the evaporation is completed, it is washed with deionized water for use.

[0135] Step 4 and Step 5 are the same as Step 4 and Step 5 in Example 1.

[0136] Example 4

[0137] Step 1 and step 2 are the same as step 1 and step 2 in Example 1.

[0138] Step 3: Self-assembly of artificial water channels on the porous polymer support layer

[0139] The porous polymer support layer base membrane completed in step 2 is immersed in a solution containing artificial water channel molecules of molecular structure type II N,N'-1,3-propylenedihydroxymethyloctyl urea. The immersion time is 30 minutes. The solution temperature is 30°C. The solution contains 2.5g / L selenium dioxide and 0.15mol / L N,N'-1,3-propylenedihydroxymethyloctyl urea. The solvent is an ethanol / water mixture with a volume ratio of 80 / 20. The solvent is evaporated by reduced pressure evaporation at a pressure of 0.02MPa while maintaining the temperature at 35°C for 5 hours. Under this condition, artificial water channel molecules are deposited. After evaporation, the solution is washed with deionized water for use.

[0140] Step 4 and Step 5 are the same as Step 4 and Step 5 in Example 1.

[0141] Example 5

[0142] Step 1 and step 2 are the same as step 1 and step 2 in Example 1.

[0143] Step 3: Self-assembly of artificial water channels on the porous polymer support layer

[0144] The porous polymer support layer base membrane completed in step 2 is immersed in a solution containing N,N'-1,3-propylenedihydroxymethylbutyl urea artificial water channel molecules of molecular structure II, the immersion time is 30 minutes, the solution temperature is 30°C, the solution components include 2.5g / L selenium dioxide, 0.15mol / LN,N'-1,3-propylenedihydroxymethylbutyl urea, the solvent is an ethanol / water mixture with a volume ratio of 80 / 20, the solvent is evaporated by reduced pressure evaporation, the pressure is 0.02MPa, while maintaining the temperature at 35°C, the evaporation time is 5h, the artificial water channel molecules are deposited under this condition, and after the evaporation is completed, it is washed with deionized water for use.

[0145] Step 4 and Step 5 are the same as Step 4 and Step 5 in Example 1.

[0146] Example 6

[0147] Step 1 and step 2 are the same as step 1 and step 2 in Example 1.

[0148] Step 3: Self-assembly of artificial aquaporins on the porous polymer support layer

[0149] The porous polymer support layer base membrane completed in step 2 is immersed in a solution containing N,N'-1,3-propylenedihydroxymethylpentyl urea artificial water channel molecules of molecular structure II, the immersion time is 30 minutes, the solution temperature is 30°C, the solution contains 2.5g / L selenium dioxide, 0.15mol / LN,N'-1,3-propylenedihydroxymethylpentyl urea, the solvent is an ethanol / water mixture with a volume ratio of 80 / 20, the solvent is evaporated by reduced pressure evaporation, the pressure is 0.02MPa, while maintaining the temperature at 35°C, the evaporation time is 5h, the artificial water channel molecules are deposited under this condition, and after the evaporation is completed, it is washed with deionized water for use.

[0150] Step 4 and Step 5 are the same as Step 4 and Step 5 in Example 1.

[0151] Example 7

[0152] Step 1 and step 2 are the same as step 1 and step 2 in Example 1.

[0153] Step 3: Self-assembly of artificial water channels on the porous polymer support layer

[0154] The porous polymer support layer base membrane completed in step 2 is immersed in a solution containing N,N'-1,3-propylenedihydroxymethylhexylurea artificial water channel molecules of molecular structure II, the immersion time is 30 minutes, the solution temperature is 30°C, the solution contains 2.5g / L selenium dioxide, 0.15mol / LN,N'-1,3-propylenedihydroxymethylhexylurea, the solvent is an ethanol / water mixture with a volume ratio of 80 / 20, the solvent is evaporated by reduced pressure evaporation, the pressure is 0.02MPa, while maintaining the temperature at 35°C, the evaporation time is 5h, the artificial water channel molecules are deposited under this condition, and after the evaporation is completed, it is washed with deionized water for use.

[0155] Step 4 and Step 5 are the same as Step 4 and Step 5 in Example 1.

[0156] Example 8

[0157] Step 1 and step 2 are the same as step 1 and step 2 in Example 1.

[0158] Step 3: Self-assembly of artificial water channels on the porous polymer support layer

[0159] The porous polymer support layer base membrane completed in step 2 is immersed in a solution containing N,N'-2,3-bis(hydroxymethyl)ethanol octyl urea artificial water channel molecules of molecular structure III, the immersion time is 30 minutes, the solution temperature is 30°C, the solution contains 2.5g / L selenium disulfide, 0.2mol / LN,N'-2,3-bis(hydroxymethyl)ethanol octyl urea, the solvent is an ethanol / water mixture with a volume ratio of 80 / 20, the solvent is evaporated by reduced pressure evaporation, the pressure is 0.02MPa, while maintaining the temperature at 35°C, the evaporation time is 5h, the artificial water channel molecules are deposited under this condition, and after the evaporation is completed, it is washed with deionized water for use.

[0160] Step 4 and Step 5 are the same as Step 4 and Step 5 in Example 1.

[0161] Diaphragm performance test

[0162] The reverse osmosis membranes prepared in the comparative example and Examples 1 to 8 were tested for their initial performance under the conditions of 150 psi pressure, 2000 ppm NaCl solution, pH = 6-7, and the flux and desalination rate of the membrane at different solution temperatures were tested. The operation time was 30 min, the temperature was 25±3°C, and the salt concentration of the produced water and the raw water was tested respectively. The desalination rate of the membrane was: (1-(salt concentration of produced water / salt concentration of inlet water))×100. The results are shown in Table 1 below.

[0163] Table 1

[0164] serial number Flux / GFD Desalination rate / % Comparison Example 20.28 99.43 Example 1 28.45 99.55 Example 2 32.25 99.56 Example 3 30.15 99.48 Example 4 28.43 99.58 Example 5 33.15 99.61 Example 6 32.13 99.52 Example 7 31.15 99.55 Example 8 33.54 99.56

[0165] From the results shown in Table 1, it can be seen that compared with the control example, the performance of the membranes obtained in all embodiments is significantly improved, the flux is increased by 40% to 65%, and the desalination rate is slightly increased by 0.05% to 0.18%. Therefore, under the same pressure conditions, the permeation efficiency is higher, achieving the expected purpose of energy saving and consumption reduction of the present invention.

[0166] It should be noted that, although the technical solution of the present invention is introduced with specific examples, those skilled in the art will appreciate that the present invention should not be limited thereto.

[0167] The embodiments of the present invention have been described above, and the above description is exemplary, not exhaustive, and is not limited to the disclosed embodiments. Many modifications and variations will be apparent to those of ordinary skill in the art without departing from the scope and spirit of the described embodiments. The selection of terms used herein is intended to best explain the principles of the embodiments, practical applications, or technical improvements in the market, or to enable other persons of ordinary skill in the art to understand the embodiments disclosed herein.

[0168] Industrial Applicability

[0169] The reverse osmosis membrane preparation method provided by the present invention effectively solves the problems of rare production, difficulty in collection, high cost, poor stability, and difficulty in large-scale application of natural water channel protein in reverse osmosis membrane preparation technology by constructing artificial water channels. The prepared reverse osmosis membrane has high flux, high desalination rate and can effectively reduce the operating pressure during its operation, thereby achieving the purpose of energy saving and consumption reduction.

Claims

1. A method for preparing a reverse osmosis membrane, characterized in that: The following steps are involved: (1) preparing a polymer solution as a casting solution, applying the casting solution to a non-woven fabric, and then solidifying the casting solution in a coagulation bath to form a film, thereby forming a porous polymer support layer base film; (2) pretreating the porous polymer support layer base membrane obtained in (1) using an aqueous solution containing a silane coupling agent; (3) contacting the pretreated porous polymer support layer base membrane obtained in (2) with a solution containing a catalyst and a substance capable of forming an artificial water channel to form an artificial water channel by self-assembly; (4) contacting the pretreated porous polymer support layer base membrane having artificial water channels obtained in (3) with an aqueous solution containing an amine monomer and an oil solution containing an acyl chloride monomer in sequence, thereby forming a polyamide functional layer; (5) After post-treatment, a reverse osmosis membrane is obtained.

2. The preparation method according to claim 1, wherein the polymer is one or more of bisphenol A type polysulfone, polyethersulfone, polyarylsulfone, polynaphthylidene ether sulfone ketone, polyaryl ether sulfone ketone, naphthalene biphenyl polyaryl ether nitrile ketone, polyacrylonitrile and sulfonated polyethersulfone.

3. The preparation method according to claim 1 or 2, wherein the silane coupling agent is one or more of 3-aminopropyltriethoxysilane, 3-aminopropyltrimethoxysilane, 3-glycidyloxypropyltrimethoxysilane, N-(2-aminoethyl)-3-aminopropylmethyldimethoxysilane, N-(2-aminoethyl)-3-aminopropyltrimethoxysilane, N-(2-aminoethyl)-3-aminopropyltriethoxysilane, vinyltriethoxysilane, vinyltrimethoxysilane, vinyltri(2-methoxyethoxy)silane, and 3-aminopropylmethyldiethoxysilane.

4. The preparation method according to claim 1 or 2, wherein the substance capable of forming an artificial water channel has one of the following molecular structures I, II and III: Wherein R is a straight or branched alkyl group having 1 to 8 carbon atoms, and X is O or S.

5. The preparation method according to claim 1 or 2, wherein the catalyst is one or more of selenium dioxide, selenium disulfide, potassium permanganate, and potassium dichromate.

6. The preparation method according to claim 1 or 2, wherein the amine monomer is o-phenylenediamine, m-phenylenediamine, p-phenylenediamine, s-phenylenediamine, polyetheramine, 3-fluoroaniline, 3-chloroaniline, aminopiperazine, 2,3-diaminopyridine, 2,6-diaminopyridine, 2,5-diaminobenzenesulfonic acid, N-phenyl-p-phenylenediamine, 1,4-phenylenediamine, m-phenylenediamine, 2,4-diaminotoluene, 2,5-diaminotoluene, 2,6-diaminotoluene, 2,4-diaminoanisole, 3, One or more of 4'-diaminodiphenyl ether, 1,2-propylenediamine, 1,3-propylenediamine, diisobutylamine, 1,2-cyclohexanediamine, n-hexylamine, heptylamine, cycloheptylamine, 1,8-octanediamine, decylamine, dodecylamine, N-ethylethylenediamine, N-butylethylenediamine, 4,5-dimethyl-1,2-phenylenediamine, 1,5-diaminonaphthalene, N,N-diethyl-p-phenylenediamine, 2-hydroxyethylpropylamine, 1,3-diamino-2-propanol and 3,3',5,5'-tetramethylbenzidine.

7. The preparation method according to claim 1 or 2, wherein the acyl chloride monomer is trimesoyl chloride, pyromellitoyl chloride, terephthaloyl chloride, isophthaloyl chloride, o-chlorobenzoyl chloride, oxalyl chloride, 3-bromopropionyl chloride, undecanoyl chloride, dodecanoyl chloride, n-valeryl chloride, 3-fluorobenzoyl chloride, 4-methoxybenzoyl chloride, 4-phenylbenzoyl chloride, p-fluorobenzoyl chloride, isovaleryl chloride, succinoyl chloride, 1,7-heptanedioyl chloride, ethyl malonate chloride, m-methylbenzoyl chloride, 2-methoxybenzoyl chloride , 4-methoxybenzoyl chloride, 4-phenylbenzoyl chloride, 3,4-dimethoxybenzoyl chloride, cyclopentylcarbonyl chloride, cyclopropylcarbonyl chloride, heptanoyl chloride, 3-phenylpropionyl chloride, o-fluorobenzenesulfonyl chloride, p-ethylbenzoyl chloride, perfluorooctanesulfonyl chloride, 2,4,6-trichlorobenzoyl chloride, 4-bromo-2-fluorobenzoyl chloride, 3,5-difluorobenzoyl chloride, 2,5-difluorobenzoyl chloride, 3,4-dichlorobenzoyl chloride, 4-n-propylbenzoyl chloride, n-butyryl chloride and 2-nitrobenzoyl chloride.

8. A reverse osmosis membrane, comprising a porous polymer support layer base membrane and a polyamide functional layer in sequence, wherein the porous polymer support layer base membrane comprises a polymer porous support layer formed on a non-woven fabric layer, characterized in that: There are artificial water channels between the porous polymer support layer base membrane and the polyamide functional layer, and the artificial water channels are formed by self-assembly of substances that can form artificial water channels.

9. The reverse osmosis membrane according to claim 8, wherein the substance capable of forming an artificial water channel has one of the following molecular structures I, II and III: Wherein R is a straight or branched alkyl group having 1 to 8 carbon atoms, and X is O or S.

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