High-performance reverse osmosis membrane for water treatment and preparation method and application thereof

Abstract

The application belongs to the technical field of membrane separation and water treatment, and particularly relates to a high-performance reverse osmosis membrane for water treatment and a preparation method and application thereof. The application proposes a new method of adding an interface regulator with an octanol / water partition coefficient Log P of-3-2 in an aqueous solution and adding a functionalized long-chain fatty acid salt in an organic phase, a long carbon chain segment forms a self-assembled layer in the organic phase, maintains a constant diffusion environment, an anion adjusts the migration of an amine monomer, and a metal cation stabilizes the interface and enhances the density of the membrane layer. Thus, the interface polymerization kinetics is precisely controlled from the organic phase side. The strategy can not only effectively improve the uniformity and density of the membrane layer, but also significantly improve the boron removal and desalination performance while maintaining high water flux.

Description

Technical Field

[0001] This invention belongs to the field of membrane separation and water treatment technology, specifically relating to a high-performance reverse osmosis membrane for water treatment, its preparation method, and its application. Background Technology

[0002] Currently, seawater desalination technology has become an important way to obtain usable freshwater. Among them, reverse osmosis (RO) membrane technology has become the mainstream process for seawater desalination due to its advantages such as low energy consumption, high-quality permeate, and stable operation. Most existing commercial RO membranes are aromatic polyamide membrane composite membranes, which form a separation layer through the interfacial polymerization reaction of aqueous aromatic diamine monomers (such as m-phenylenediamine, MPD) and organic polyacrylamide chlorides (such as trimesoyl chloride, TMC). This type of membrane can achieve a salt rejection rate of over 99.5%, but it is insufficient in removing neutral small molecule boric acid (H3BO3) from seawater. Therefore, improving the boron removal capacity of RO membranes has always been an important research direction in this field.

[0003] In recent years, many researchers have attempted to regulate the rate of interfacial polymerization and the membrane structure by introducing surfactants into aqueous systems. For example, common anionic surfactants such as sodium dodecyl sulfate (SDS) and sodium dodecylbenzene sulfonate (SDBS) have been widely used to improve the diffusion behavior of monomers in the aqueous phase and interfacial tension, thereby optimizing the membrane density and surface morphology to some extent. However, these regulatory methods mainly act on the aqueous phase side, and research on their impact on the diffusion symmetry between the two phases and the reaction environment of the organic phase remains insufficient.

[0004] Currently, there is limited research on the reverse control of interfacial polymerization processes by adding surfactants to the organic phase. Existing technology CN114247303A discloses the addition of nonionic surfactants to an oil phase solution, which utilizes the reaction between the oil phase monomer and the active groups on the nonionic surfactant. However, polar groups (such as hydroxyl and ether bonds) undergo side reactions with acyl chlorides, reducing controllability and repeatability. CN107126850A discloses the addition of anionic surfactants such as sodium dodecyl sulfonate to a sulfonyl chloride organic phase solution to promote the reaction between the two phases, thereby increasing the degree of crosslinking. However, short-chain surfactants such as SDS have relatively short carbon chains (C... 12 Its limited solubility in the organic phase and unstable interfacial adsorption easily lead to interfacial fluctuations and uneven local polymerization. Its surface activity is more concentrated on the aqueous phase side, and its effect on regulating monomer diffusion in the organic phase is limited.

[0005] Furthermore, polyamide reverse osmosis membranes with nodular structures have been proven to have high rejection rates. The fabrication of nodular polyamide reverse osmosis membranes with high surface area ratios is expected to improve rejection rates while simultaneously increasing membrane flux. Therefore, how to fabricate nodular polyamide reverse osmosis membranes with high surface area ratios through interface control to simultaneously achieve high rejection rates, high flux, and high boron removal rates is a pressing issue that needs to be addressed. Summary of the Invention

[0006] To address the aforementioned problems, this invention proposes a novel method of adding functionalized long-chain fatty acid salts to the organic phase. The long carbon segments form a self-assembled layer in the organic phase, maintaining a constant diffusion environment. Anions regulate the migration of amine monomers, while metal cations stabilize the interface and enhance membrane density. This allows for precise control of interfacial polymerization kinetics from the organic phase side. This strategy not only effectively improves the uniformity and density of the membrane but also significantly enhances deboronization and desalination performance while maintaining high water flux.

[0007] Specifically, this invention provides a method for preparing a high-performance reverse osmosis membrane for water treatment. A porous base membrane is sequentially contacted with an aqueous solution and an organic solution via interfacial polymerization to form a polyamide reverse osmosis membrane. An interfacial regulator with an octanol / water partition coefficient Log P of -3 to 2 is added to the aqueous solution, and a long-chain fatty acid salt with an octanol / water partition coefficient Log P greater than 0 is added to the organic solution. The long-chain fatty acid salt has a C anode. 15 –C 20 The polyamide reverse osmosis membrane contains saturated or unsaturated fatty acid ions, and its cation is a metal cation. The surface of the polyamide reverse osmosis membrane has at least 75% nodular regions.

[0008] As a preferred embodiment, the long-chain fatty acid salt is a straight-chain or branched hydrocarbon group containing 0–4 C=C or 0–1 C≡C.

[0009] As a preferred embodiment, the anion of the long-chain fatty acid salt is selected from any one or a combination of two or more of pentadecanoic acid, pentadecenoic acid, palmitic acid, palmitoleic acid, heptadecanoic acid, heptadecanoic acid, stearic acid, oleic acid, linoleic acid, linolenic acid, octadecanoic acid, nonadecanoic acid, nonadecanoic acid, arachidic acid, eicosenoic acid, eicosadienoic acid, eicostrienoic acid, and arachidonic acid; the long-chain fatty acid salt has 0-3 functionalized groups, which are selected from: hydroxyl, carbonyl, ether, aldehyde, halogen, terminal alkenyl, terminal alkynyl, ester, or amide.

[0010] As a preferred embodiment, the interface regulator is selected from one or more of camphor sulfonic acid, phosphoric acid, potassium hydrogen tartrate, ethanolamine, dimethyl sulfoxide, and citric acid.

[0011] As a preferred embodiment, the concentration of the long-chain fatty acid salt in the organic phase solution is 0.01-1 wt%.

[0012] As a preferred embodiment, the metal cation is Na. + K + Ca 2+ Mg 2+ Zn 2+ Cu 2+ Fe 2+ or Fe 3+ One or more of them.

[0013] Preferably, the concentration of the polyacrylamide chloride monomer in the organic phase solution is 0.01-5 wt%; the polyacrylamide chloride monomer is selected from one or more of the following: trimesoyl chloride, terephthaloyl chloride, isophthaloyl chloride, biphenyl dicarboxylate chloride, biphenyl trimesoyl chloride, biphenyl tetracarboxylate chloride, naphthalene dicarboxylate chloride, naphthalene trimesoyl chloride, naphthalene tetracarboxylate chloride, malonyl chloride, succinyl chloride, glutaryl chloride, and adipyl chloride; the organic solvent in the organic phase solution is selected from hexane, heptane, octane, nonane, decane, undecane, dodecane, Isopar C, Isopar E, Isopar G, Isopar H, Isopar L, and Isopar One or more of M; the aqueous solution contains a polyamine monomer, the concentration of which is 0.5-5 wt%; the polyamine monomer is selected from one or more of o-phenylenediamine, m-phenylenediamine, p-phenylenediamine, 1,3,5-triaminobenzene, diaminotoluene, ethylenediamine, propylenediamine, butanediamine, diaminocyclohexane, and piperazine.

[0014] As a preferred embodiment, the contact time between the surface of the porous base membrane and the aqueous solution is 1-300 s; the contact time between the surface of the porous base membrane and the organic solution is 1-300 s; the material of the porous base membrane is selected from one of polysulfone, polyphenylsulfone, polyethersulfone, polyvinylidene fluoride, polytetrafluoroethylene, polyethylene, polypropylene, polyimide, polyetherimide, polyacrylonitrile, polyphenylene ether, polyphenylene sulfide, polyetherketone, and polyaryletherketone.

[0015] As a preferred method, after the polyamide reverse osmosis membrane is formed by interfacial polymerization, the polyamide separation layer is post-treated, and the post-treatment is selected from one or more of diazotization treatment, acylation treatment, amination treatment or surface grafting modification.

[0016] The present invention also provides a high-performance reverse osmosis membrane for water treatment prepared according to the above preparation method, which can be used in desalination and deboronization.

[0017] Compared with the prior art, the present invention has the following advantages:

[0018] (1) Bidirectional regulation of reaction kinetics: Traditional short-chain surfactants such as SDS and SDBS (carbon chain number C) 12 –C 14 This invention can only function in the aqueous phase, and its regulation is limited to one side of the diffusion path, which easily leads to a mismatch in diffusion rates between the two phases. The present invention adds an interface regulator with an octanol / water partition coefficient Log P of -3 to 2 to the aqueous solution, and introduces a self-assembling long-chain fatty acid salt with an octanol / water partition coefficient Log P greater than 0 into the organic phase. This simultaneously regulates the chemical potential and diffusion gradient on both sides of the interface, forming a more balanced and mild polymerization environment, thereby obtaining a polyamide reverse osmosis membrane with at least 70% nodular regions on its surface.

[0019] (2) Significantly improved interfacial structural stability: Short-chain surfactants have poor solubility in the organic phase and are prone to aggregation or migration to the aqueous phase, resulting in unstable reaction interfaces. Long-chain fatty acid salts, on the other hand, have stronger hydrophobicity and higher molecular orientation ability, and can self-assemble into a stable molecular layer at the oil / water interface, effectively reducing interfacial tension, avoiding local turbulence and non-uniform polymerization, making the reaction interface smoother and more stable, which is conducive to the formation of a continuous and defect-free separation layer.

[0020] (3) Continuous diffusion regulation and film formation reproducibility: Long-chain fatty acid salts have low solubility but uniform distribution in the organic phase, and can persist throughout the reaction process and stably control the cross-interfacial diffusion of amine monomers. Compared with short-chain surfactants, which are consumed or migrated early in the reaction, long-chain systems have a more persistent regulatory effect, significantly improving the reproducibility and batch-to-batch consistency of membrane preparation.

[0021] (4) Synergistic effect of metal cations: The long-chain fatty acid salts used in this invention are usually in the form of metal salts, and their cations (such as Na) + K + Ca² + Zn² + At the interface, cations play an important synergistic role: on the one hand, cations can form weak coordination with acyl chloride groups or amine groups, inhibiting local overreaction and chain segment breakage; on the other hand, divalent cations (such as Zn) have a significant synergistic effect. 2+ Ca 2+ It can enhance the electrostatic shielding and network stability between molecules, and improve the density and alkali resistance of the polyamide layer; in addition, the electric field effect of metal ions can induce the orientation of interfacial molecules, making the film structure more regular, which helps to achieve the synergistic improvement of high desalination and high deboronization. Attached Figure Description

[0022] Figure 1These are scanning electron microscope (SEM) images of the surface and cross-section of the reverse osmosis membranes obtained in Examples 1-6 and Comparative Examples 1-3, wherein the SEM images of the surface of the reverse osmosis membranes obtained in Examples 1-6 and Comparative Examples 1-3 are magnified to 50,000. Detailed Implementation

[0023] The following is a further detailed description of the present invention in conjunction with specific preferred embodiments, and it should not be construed that the specific implementation of the present invention is limited to these descriptions. For those skilled in the art, various simple deductions or substitutions can be made without departing from the concept of the present invention, and all such modifications and substitutions should be considered within the scope of protection of the present invention. Specific conditions not specified in the embodiments are performed according to conventional conditions or conditions recommended by the manufacturer. Unless otherwise specified, all reagents or instruments used are conventional products obtained through commercial channels.

[0024] Example 1

[0025] This embodiment provides a method for preparing a high-performance seawater desalination reverse osmosis membrane. The specific preparation process is as follows:

[0026] (1) Preparation of aqueous solution

[0027] m-phenylenediamine, camphor sulfonic acid, and triethylamine were added sequentially to deionized water to prepare a homogeneous and transparent aqueous solution. The concentrations of each component in the aqueous solution were as follows: 3.3 wt% m-phenylenediamine, 3 wt% camphor sulfonic acid (Log P = -1.8), and 2 wt% triethylamine.

[0028] (2) Preparation of organic phase solution

[0029] Tristyroyl chloride and sodium stearate were added to Isopar G organic solvent to prepare a homogeneous and transparent organic phase solution. The concentrations of the components in the organic phase solution were as follows: 0.2 wt% tristyroyl chloride and 0.01 wt% sodium stearate (Log P = 8.2).

[0030] (3) Contact the surface of the polysulfone membrane with the aqueous solution prepared in step (1) for 10s, remove the excess aqueous solution on the surface, and contact the membrane layer formed by the aqueous solution with the organic solution prepared in step (2) to undergo interfacial polymerization reaction for 10s. After the reaction is completed, remove the excess organic solution on the surface to obtain the nascent reverse osmosis membrane.

[0031] (4) Heat-treat the nascent reverse osmosis membrane in a 90℃ oven for 6 minutes.

[0032] (5) Rinse the reverse osmosis membrane prepared in step (4) with deionized water.

[0033] Example 2

[0034] This embodiment provides a method for preparing a high-performance seawater desalination reverse osmosis membrane. The specific preparation process is as follows:

[0035] (1) Preparation of aqueous solution

[0036] m-phenylenediamine, camphor sulfonic acid, and triethylamine were added sequentially to deionized water to prepare a homogeneous and transparent aqueous solution. The concentrations of each component in the aqueous solution were as follows: 3.3 wt% m-phenylenediamine, 3 wt% camphor sulfonic acid (Log P = -1.8), and 2 wt% triethylamine.

[0037] (2) Preparation of organic phase solution

[0038] Tristyroyl chloride and magnesium stearate were added to Isopar G organic solvent to prepare a homogeneous and transparent organic phase solution. The concentrations of the components in the organic phase solution were as follows: 0.2 wt% tristyroyl chloride and 0.01 wt% magnesium stearate (Log P = 10.0).

[0039] (3) Contact the surface of the polysulfone membrane with the aqueous solution prepared in step (1) for 10s, remove the excess aqueous solution on the surface, and contact the membrane layer formed by the aqueous solution with the organic solution prepared in step (2) to undergo interfacial polymerization reaction for 10s. After the reaction is completed, remove the excess organic solution on the surface to obtain the nascent reverse osmosis membrane.

[0040] (4) Heat-treat the nascent reverse osmosis membrane in a 90℃ oven for 6 minutes.

[0041] (5) Rinse the reverse osmosis membrane prepared in step (4) with deionized water.

[0042] Example 3

[0043] This embodiment provides a method for preparing a reverse osmosis membrane, and the specific preparation process is as follows:

[0044] (1) Preparation of aqueous solution

[0045] m-phenylenediamine, camphor sulfonic acid, and triethylamine were added sequentially to deionized water to prepare a homogeneous and transparent aqueous solution. The concentrations of each component in the aqueous solution were as follows: 3.3 wt% m-phenylenediamine, 3 wt% camphor sulfonic acid (Log P = -1.8), and 2 wt% triethylamine.

[0046] (2) Preparation of organic phase solution

[0047] Tristyroyl chloride and sodium oleate were added to Isopar G organic solvent to prepare a homogeneous and transparent organic phase solution. The concentrations of the components in the organic phase solution were as follows: 0.2 wt% tristyroyl chloride and 0.01 wt% sodium oleate (Log P = 6.8).

[0048] (3) Contact the surface of the polysulfone membrane with the aqueous solution prepared in step (1) for 10s, remove the excess aqueous solution on the surface, and contact the membrane layer formed by the aqueous solution with the organic solution prepared in step (2) to undergo interfacial polymerization reaction for 10s. After the reaction is completed, remove the excess organic solution on the surface to obtain the nascent reverse osmosis membrane.

[0049] (4) Heat-treat the nascent reverse osmosis membrane in a 90℃ oven for 6 minutes.

[0050] (5) Rinse the reverse osmosis membrane prepared in step (4) with deionized water.

[0051] Example 4

[0052] This embodiment provides a method for preparing a high-performance seawater desalination reverse osmosis membrane. The specific preparation process is as follows:

[0053] (1) Preparation of aqueous solution

[0054] m-phenylenediamine, camphor sulfonic acid, and triethylamine were added sequentially to deionized water to prepare a homogeneous and transparent aqueous solution. The concentrations of each component in the aqueous solution were as follows: 3.3 wt% m-phenylenediamine, 3 wt% camphor sulfonic acid (Log P = -1.8), and 2 wt% triethylamine.

[0055] (2) Preparation of organic phase solution

[0056] Tristyroyl chloride and sodium linoleate were added to Isopar G organic solvent to prepare a homogeneous and transparent organic phase solution. The concentrations of the components in the organic phase solution were as follows: 0.2 wt% tristyroyl chloride and 0.01 wt% sodium linoleate (Log P = 6.5).

[0057] (3) Contact the surface of the polysulfone membrane with the aqueous solution prepared in step (1) for 10s, remove the excess aqueous solution on the surface, and contact the membrane layer formed by the aqueous solution with the organic solution prepared in step (2) to undergo interfacial polymerization reaction for 10s. After the reaction is completed, remove the excess organic solution on the surface to obtain the nascent reverse osmosis membrane.

[0058] (4) Heat-treat the nascent reverse osmosis membrane in a 90℃ oven for 6 minutes.

[0059] (5) Rinse the reverse osmosis membrane prepared in step (4) with deionized water.

[0060] Example 5

[0061] This embodiment provides a method for preparing a high-performance seawater desalination reverse osmosis membrane. The specific preparation process is as follows:

[0062] (1) Preparation of aqueous solution

[0063] m-phenylenediamine, camphor sulfonic acid, and triethylamine were added sequentially to deionized water to prepare a homogeneous and transparent aqueous solution. The concentrations of each component in the aqueous solution were as follows: 3.3 wt% m-phenylenediamine, 3 wt% camphor sulfonic acid (Log P = -1.8), and 2 wt% triethylamine.

[0064] (2) Preparation of organic phase solution

[0065] Tristyroyl chloride and sodium palmitate were added to Isopar G organic solvent to prepare a homogeneous and transparent organic phase solution. The concentrations of the components in the organic phase solution were as follows: 0.2 wt% tristyroyl chloride and 0.01 wt% sodium palmitate (Log P = 6.4).

[0066] (3) Contact the surface of the polysulfone membrane with the aqueous solution prepared in step (1) for 10s, remove the excess aqueous solution on the surface, and contact the membrane layer formed by the aqueous solution with the organic solution prepared in step (2) to undergo interfacial polymerization reaction for 10s. After the reaction is completed, remove the excess organic solution on the surface to obtain the nascent reverse osmosis membrane.

[0067] (4) Heat-treat the nascent reverse osmosis membrane in a 90℃ oven for 6 minutes.

[0068] (5) Rinse the reverse osmosis membrane prepared in step (4) with deionized water.

[0069] Example 6

[0070] This embodiment provides a method for preparing a high-performance seawater desalination reverse osmosis membrane. The specific preparation process is as follows:

[0071] (1) Preparation of aqueous solution

[0072] m-phenylenediamine, camphor sulfonic acid, and triethylamine were added sequentially to deionized water to prepare a homogeneous and transparent aqueous solution. The concentrations of each component in the aqueous solution were as follows: 3.3 wt% m-phenylenediamine, 3 wt% camphor sulfonic acid (Log P = -1.8), and 2 wt% triethylamine.

[0073] (2) Preparation of organic phase solution

[0074] Tristyroyl chloride and sodium arachidate were added to Isopar G organic solvent to prepare a homogeneous and transparent organic phase solution. The concentrations of the components in the organic phase solution were as follows: 0.2 wt% tristyroyl chloride and 0.01 wt% sodium arachidate (Log P = 8.7).

[0075] (3) Contact the surface of the polysulfone membrane with the aqueous solution prepared in step (1) for 10s, remove the excess aqueous solution on the surface, and contact the membrane layer formed by the aqueous solution with the organic solution prepared in step (2) to undergo interfacial polymerization reaction for 10s. After the reaction is completed, remove the excess organic solution on the surface to obtain the nascent reverse osmosis membrane.

[0076] (4) Heat-treat the nascent reverse osmosis membrane in a 90℃ oven for 6 minutes.

[0077] (5) Rinse the reverse osmosis membrane prepared in step (4) with deionized water.

[0078] Comparative Example 1

[0079] The difference between this comparative example and Example 1 is that sodium stearate was not added to the organic phase solution, while all other aspects remained the same as in Example 1.

[0080] Comparative Example 2

[0081] The difference between this comparative example and Example 1 is that sodium stearate was added to the aqueous solution at a concentration of 0.01 wt%, while the rest remained the same as in Example 1.

[0082] Comparative Example 3

[0083] The difference between this comparative example and Example 1 is that sodium dodecyl sulfate is added to the organic phase solution instead of sodium stearate, while the rest are the same as in Example 1.

[0084] Test Example 1

[0085] The performance of the reverse osmosis membranes obtained in all embodiments and comparative examples was tested. In this experiment, a cross-flow filtration device was used to test the water flux and desalination rate of the reverse osmosis membranes. The effective membrane area of ​​a single rectangular test unit was 42 cm². 2 The feed solution was prepared using sodium chloride (32 g / L) and boric acid (5 mg / L), with the feed solution temperature controlled at 25.0 ± 0.2 °C. After a 3-hour pre-compression treatment at an operating pressure of 800 psi (5.5 MPa), the filtrate was collected after 30 minutes. The volume of filtrate produced per unit time and per unit membrane area is the water flux (LMH). The desalination rate (%) = (feed solution conductivity - filtrate conductivity) / feed solution conductivity × 100%. The boric acid concentration was measured by inductively coupled plasma mass spectrometry (ICP-MS), and the boron removal rate (%) = (feed solution concentration - filtrate concentration) / feed solution concentration × 100%. Figure 1 SEM images of Examples 1-6 and Comparative Examples 1-3 were analyzed using ImageJ software to determine the area ratio of the "nodular structure" region. The water flux, desalination and deboron removal performance results of each reverse osmosis membrane, along with the structural area test ratio, are shown in Table 1.

[0086] Table 1 Performance test results of reverse osmosis membranes obtained in Examples 1-6 and Comparative Examples 1-3

[0087]

[0088] As shown in Table 1, the membranes of Examples 1–6 exhibited significantly better desalination and deboronization rates than the comparative examples after adding camphor sulfonic acid to the aqueous phase and long-chain fatty acid salts to the organic phase. The boric acid rejection rate increased by approximately 8–12%. This indicates that camphor sulfonic acid and long-chain fatty acid salts can effectively regulate the interfacial polymerization rate and promote the crosslinking and densification of the polyamide layer. Comparative Example 2 shows that when sodium stearate is added to the aqueous phase, its long-chain structure alters the solvation environment of the aqueous phase, thus inhibiting the polymerization reaction, indicating that its optimal site of action is in the organic phase. The limited regulatory effect of sodium dodecyl sulfate in the organic phase in Comparative Example 3 further verifies the unique advantages of the anionic structure of long-chain fatty acid salts in stabilizing the interface and promoting controllable reaction.

[0089] Test Example 2

[0090] The surfaces of the reverse osmosis membranes obtained in Examples 1-6 and Comparative Examples 1-3 were observed using a scanning electron microscope. The SEM images of the reverse osmosis membrane surfaces in Examples 1-6 and Comparative Examples 1-3 were obtained at a magnification of 50,000. The results are as follows: Figure 1 As shown.

[0091] In Comparative Examples 1–3, the membrane surface exhibited a typical heterogeneous leaf-like structure with obvious wrinkles and pores in some areas. The nodules were sparsely distributed and the interface edges were relatively sharp, indicating a rapid interfacial polymerization rate and uneven reaction, resulting in microporous defects in the membrane layer and insufficient boron removal selectivity. In particular, in Comparative Example 3 (with sodium dodecyl sulfate added to the organic phase), although the interface was slightly improved, large areas of leaf-like protrusions were still visible, indicating that its regulatory effect was limited.

[0092] The samples from Examples 1–6 (with different long-chain fatty acid salts, such as sodium stearate, sodium oleate, and their derivatives, added to the organic phase) exhibited significantly different morphological characteristics: the overall film layer was smoother and denser, the leaf-like structure gradually weakened and merged with the nodular structure; the nodules were continuously distributed, and the surface protrusions were small and regular, forming a uniform micronodule-microprotrusion morphology. This morphology indicates that long-chain fatty acid salts can effectively regulate the monomer diffusion rate in the organic phase, inhibit excessively rapid interfacial reactions, and thus promote the orderly cross-linking and growth of polyamide segments. With the increase of carbon chain length and the number of functional groups (such as sodium oleate and sodium linoleate), the nodules gradually transitioned into a soft protrusion morphology, the specific surface area increased significantly, providing more water molecule transport channels while maintaining high density.

[0093] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them. The basic principles and main features of the present invention have been described above with specific implementation schemes. Based on the present invention, some modifications or substitutions can be made, but these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of protection claimed by the present invention.

Claims

1. A method for preparing a high-performance reverse osmosis membrane for water treatment, comprising sequentially contacting a porous base membrane with an aqueous phase solution and an organic phase solution via interfacial polymerization to form a polyamide reverse osmosis membrane, characterized in that, An interface regulator with an octanol / water partition coefficient Log P of -3 to 2 is added to the aqueous phase solution, and a long-chain fatty acid salt with an octanol / water partition coefficient Log P greater than 0 is added to the organic phase solution. The anion of the long-chain fatty acid salt is C. 15 –C 20 The polyamide reverse osmosis membrane contains saturated or unsaturated fatty acid ions, and its cation is a metal cation. The surface of the polyamide reverse osmosis membrane has at least 75% nodular regions.

2. The preparation method according to claim 1, characterized in that, The long-chain fatty acid salt is a straight-chain or branched hydrocarbon group, containing 0–4 C=C or 0–1 C≡C; the anion of the long-chain fatty acid salt is selected from any one or a combination of two or more of pentadecanoic acid, pentadecenoic acid, palmitic acid, palmitoleic acid, heptadecanoic acid, heptadecanoic acid, stearic acid, oleic acid, linoleic acid, linolenic acid, octadecanoic acid, nonadecanoic acid, nonadecanoic acid, arachidic acid, eicosenoic acid, eicosadienoic acid, eicostrienoic acid, and arachidonic acid; the long-chain fatty acid salt has 0–3 functional groups, which are selected from: hydroxyl, carbonyl, ether, aldehyde, halogen, terminal alkenyl, terminal alkynyl, ester, or amide.

3. The preparation method according to claim 1, characterized in that, The interface regulator is selected from one or more of camphor sulfonic acid, phosphoric acid, potassium hydrogen tartrate, ethanolamine, dimethyl sulfoxide, and citric acid.

4. The preparation method according to claim 1, characterized in that, The concentration of the long-chain fatty acid salt in the organic phase solution is 0.01-1 wt%.

5. The preparation method according to claim 1, characterized in that, The metal cation is Na. + K + Ca 2+ Mg 2 + Zn 2+ Cu 2+ Fe 2+ or Fe 3+ One or more of them.

6. The preparation method according to claim 1, characterized in that, The concentration of the polyacrylamide chloride monomer in the organic phase solution is 0.01-5 wt%; the polyacrylamide chloride monomer is selected from one or more of the following: trimesoyl chloride, terephthaloyl chloride, isophthaloyl chloride, biphenyl dicarboxylate chloride, biphenyl trimesoyl chloride, biphenyl tetracarboxylate chloride, naphthalene dicarboxylate chloride, naphthalene trimesoyl chloride, naphthalene tetracarboxylate chloride, malonyl chloride, succinyl chloride, glutaryl chloride, and adipyl chloride; the organic solvent in the organic phase solution is selected from hexaane, heptane, octane, nonane, decane, undecane, dodecane, Isopar C, Isopar E, Isopar G, Isopar H, Isopar L, and Isopar One or more of M; the aqueous solution contains a polyamine monomer, the concentration of which is 0.5-5 wt%; the polyamine monomer is selected from one or more of o-phenylenediamine, m-phenylenediamine, p-phenylenediamine, 1,3,5-triaminobenzene, diaminotoluene, ethylenediamine, propylenediamine, butanediamine, diaminocyclohexane, and piperazine.

7. The preparation method according to claim 1, characterized in that, The contact time between the surface of the porous base membrane and the aqueous solution is 1-300s; the contact time between the surface of the porous base membrane and the organic solution is 1-300s; the material of the porous base membrane is selected from one of polysulfone, polyphenylsulfone, polyethersulfone, polyvinylidene fluoride, polytetrafluoroethylene, polyethylene, polypropylene, polyimide, polyetherimide, polyacrylonitrile, polyphenylene ether, polyphenylene sulfide, polyetherketone, and polyaryletherketone.

8. The preparation method according to claim 1, characterized in that, After the polyamide reverse osmosis membrane is formed by interfacial polymerization, the polyamide separation layer is post-treated. The post-treatment is selected from one or more of diazotization, acylation, amination, or surface grafting modification.

9. A high-performance reverse osmosis membrane for water treatment prepared by the preparation method according to claim 1.

10. The application of the high-performance reverse osmosis membrane for water treatment according to claim 9 in desalination and deboron removal.

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