Polyamide reverse osmosis membrane as well as preparation method and application thereof

Abstract

The invention relates to a polyamide reverse osmosis membrane as well as a preparation method and application thereof. The preparation method of the polyamide reverse osmosis membrane comprises the following steps: applying an aqueous solution of rhodamine B to a base membrane to prepare a first workpiece; enabling the first workpiece to be in contact with a water-phase solution of a diamine compound and an oil-phase solution of polyacyl chloride, and performing interfacial polymerization reaction on the first workpiece to prepare the polyamide reverse osmosis membrane. The polyamide reverse osmosis membrane prepared by the preparation method has high desalting performance and relatively high flux.

Description

Technical Field

[0001] The present application relates to a reverse osmosis membrane, and in particular to a polyamide reverse osmosis membrane and a preparation method and application thereof. Background Art

[0002] As a semipermeable membrane material that efficiently retains salt and other impurities in water, reverse osmosis membranes are widely used in water treatment and related fields due to their core properties of "preferential permeation of water molecules under pressure while solutes are retained." Their high desalination performance is key to achieving water purification. Reverse osmosis membrane materials can be divided into two major categories: organic polymer materials and inorganic materials. Polyamide reverse osmosis membranes have become the mainstream commercial reverse osmosis membrane due to their high salt rejection rate.

[0003] However, it is usually difficult to achieve both high desalination performance and high flux of reverse osmosis membranes. This is because the desalination and flux performance of reverse osmosis membranes are determined by their microstructure, such as pore size, distribution, density, hydrophilicity, etc., and the effects of these structural parameters on the two are often "one increases while the other decreases". Traditional methods focus on structural modification of reverse osmosis membranes in order to achieve high flux effects, such as constructing a small molecule polyol functional layer on the surface of the reverse osmosis membrane, and using organic strong base solutions to post-treat the reverse osmosis membrane. There are also some methods that use imidazole or carboxylic acid compounds to regulate the interface during the polyamide polymerization process to prepare high-flux reverse osmosis membranes. However, the effects of these methods are not ideal, and it is difficult to achieve an effective improvement in flux while maintaining the high desalination performance of the reverse osmosis membrane. Summary of the Invention

[0004] Based on this, the present application provides a polyamide reverse osmosis membrane that can effectively improve the flux while maintaining high desalination performance, as well as a preparation method and application thereof.

[0005] In a first aspect of the present application, a method for preparing a polyamide reverse osmosis membrane is provided, comprising the following steps:

[0006] Applying an aqueous solution of Rhodamine B to the base film to prepare a first article;

[0007] The first component is brought into contact with an aqueous solution of a diamine compound and an oily solution of a polyacid chloride, and an interfacial polymerization reaction is performed on the first component to prepare a polyamide reverse osmosis membrane.

[0008] In one embodiment, the mass concentration of Rhodamine B in the aqueous solution of Rhodamine B is 0.01% to 0.1%.

[0009] In one embodiment, the step of contacting the first article with an aqueous solution of a diamine compound and an oily solution of a polyacyl chloride comprises:

[0010] immersing the first article in the aqueous solution of the diamine compound, taking it out, and preparing a second article;

[0011] The oil phase solution of the polyacid chloride is sprayed on one side of the second component.

[0012] In one embodiment, the mass concentration of the diamine compound in the aqueous solution of the diamine compound is 1.5% to 3.5%; and / or,

[0013] In the oil phase solution of the polyacid chloride, the mass concentration of the polyacid chloride is 0.1% to 0.3%.

[0014] In one embodiment, the diamine compound includes one or more of m-phenylenediamine, p-phenylenediamine and piperazine; and / or,

[0015] The polyacid chloride includes one or both of trimesoyl chloride and isophthaloyl chloride.

[0016] In one embodiment, the interfacial polymerization reaction time is 6s~60s, and can be optionally 10s~30s.

[0017] In one embodiment, after the interfacial polymerization reaction is completed, the process further includes oxidant post-treatment, moisturizing treatment and drying treatment;

[0018] Optionally, the oxidant post-treatment includes: immersing the workpiece after the interfacial polymerization reaction in an aqueous solution of the oxidant for treatment;

[0019] Further optionally, in the aqueous solution of the oxidant, the mass concentration of the oxidant is 50ppm~500ppm;

[0020] Further optionally, the oxidant comprises sodium hypochlorite;

[0021] Further optionally, the time for immersing in the aqueous solution of the oxidant for treatment is 30s to 120s;

[0022] Optionally, the moisturizing treatment includes: immersing the workpiece after the oxidant post-treatment in an aqueous solution of a moisturizing agent for treatment;

[0023] Further optionally, in the aqueous solution of the moisturizing agent, the mass concentration of the moisturizing agent is 2% to 20%;

[0024] Further optionally, the moisturizing agent includes one or both of glycerin and citric acid;

[0025] Further optionally, the time for immersing in the aqueous solution of the moisturizing agent for treatment is 10s to 120s;

[0026] Optionally, the drying conditions include: a temperature of 40° C. to 90° C. and a time of 30 seconds to 180 seconds.

[0027] In a second aspect of the present application, a polyamide reverse osmosis membrane is provided, which is prepared by the method for preparing the polyamide reverse osmosis membrane according to the first aspect;

[0028] Optionally, the permeate flux of the polyamide reverse osmosis membrane is ≥100 L / (m 2 •h);

[0029] Optionally, the polyamide reverse osmosis membrane has a salt rejection rate of ≥88%.

[0030] The third aspect of the present application provides the use of the polyamide reverse osmosis membrane described in the second aspect in water treatment.

[0031] A fourth aspect of the present application provides a water treatment method, comprising the following steps:

[0032] The polyamide reverse osmosis membrane described in the second aspect is used for treatment;

[0033] Optionally, the treatment pressure is ≤1.55 MPa.

[0034] The present application introduces Rhodamine B during the interfacial polymerization of polyamide monomers, namely diamine compounds and polyacyl chlorides on the base membrane. The specific molecular structure of Rhodamine B can interfere with the cross-linking density and regulate the polymerization kinetics to form a loose but pore-controllable polyamide layer. Its hydrophilicity and induced surface micro-wrinkles can synergistically improve the permeability of water molecules, while relying on selective channels to maintain the salt ion retention ability. In this way, the prepared polyamide reverse osmosis membrane maintains high desalination performance while having a higher flux. DETAILED DESCRIPTION

[0035] The polyamide reverse osmosis membrane of the present application, its preparation method, and its application are further described in detail below with reference to specific examples. The present application can be implemented in many different forms and is not limited to the embodiments described herein. On the contrary, the purpose of providing these embodiments is to provide a more thorough and comprehensive understanding of the disclosure of the present application.

[0036] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art to which this application pertains. The terms used herein in the specification of this application are for the purpose of describing specific embodiments only and are not intended to limit this application.

[0037] The optional scope of the terms "and / or", "or / and", and "and / or" used in this document includes any one of two or more related listed items, and also includes any and all combinations of the related listed items, and the said any and all combinations include any two related listed items, any more related listed items, or a combination of all related listed items.

[0038] As used herein, "one or more" refers to any one, any two, or any two or more of the listed items.

[0039] In this application, terms such as "first aspect," "second aspect," and "third aspect" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or quantity, nor as implicitly indicating the importance or quantity of the technical features indicated. Furthermore, terms such as "first," "second," and "third," etc., are intended only to provide a non-exhaustive enumeration and description and should not constitute a closed-ended limitation on quantity.

[0040] In this application, the technical features described in an open manner include closed technical solutions composed of the listed features, and also include open technical solutions containing the listed features.

[0041] In this application, when referring to numerical ranges, unless otherwise specified, the numerical ranges are considered continuous and include the minimum and maximum values ​​of the range, as well as every value between such minimum and maximum values. Further, when a range refers to an integer, every integer between the minimum and maximum values ​​of the range is included. In addition, when multiple ranges are provided to describe a feature or characteristic, the ranges can be combined. In other words, unless otherwise specified, all ranges disclosed herein should be understood to include any and all subranges subsumed therein.

[0042] Unless otherwise specified, the percentage contents mentioned in this application refer to mass percentage for solid-liquid mixture and solid-solid mixture, and refer to volume percentage for liquid-liquid mixture.

[0043] The percentage concentrations mentioned in this application, unless otherwise specified, refer to the final concentration, which refers to the percentage of the added component in the system after the addition of the component.

[0044] The temperature parameters in this application, unless otherwise specified, allow for both constant temperature treatment and treatment within a certain temperature range. The constant temperature treatment allows for temperature fluctuations within the precision range of instrument control. Unless otherwise specified, all steps in this application are performed at room temperature, which generally refers to 4°C to 30°C, preferably 20±5°C.

[0045] In some embodiments of the present application, a method for preparing a polyamide reverse osmosis membrane is provided, comprising the following steps:

[0046] Applying an aqueous solution of Rhodamine B to the base film to prepare a first article;

[0047] The first component is brought into contact with an aqueous solution of a diamine compound and an oily solution of a polyacid chloride, and an interfacial polymerization reaction is performed on the first component to prepare a polyamide reverse osmosis membrane.

[0048] It is understood that the CAS number of rhodamine B is 81-88-9, and its structure is as follows:

[0049]

[0050] In some embodiments, the mass concentration of rhodamine B in the aqueous solution of rhodamine B is 0.01% to 0.1%. Specifically, the mass concentration of rhodamine B includes, but is not limited to, 0.01%, 0.02%, 0.03%, 0.04%, 0.05%, 0.06%, 0.07%, 0.08%, 0.09%, 0.1%, or a range between any two of the foregoing.

[0051] Without limitation, the step of applying the aqueous solution of Rhodamine B to the base film includes: spraying the aqueous solution of Rhodamine B on the base film.

[0052] Without limitation, the base membrane may be a base membrane commonly used in the art, such as a polysulfone base membrane.

[0053] In some embodiments, the step of contacting the first article with an aqueous solution of a diamine compound and an oily solution of a polyacyl chloride comprises:

[0054] immersing the first article in the aqueous solution of the diamine compound, taking it out, and preparing a second article;

[0055] The oil phase solution of the polyacid chloride is sprayed on one side of the second component.

[0056] It can be understood that the polyamide coating is usually prepared only on one side of the base membrane, and this side is usually the front side of the polyamide reverse osmosis membrane, that is, the water inlet side.

[0057] In some embodiments, the mass concentration of the diamine compound in the aqueous solution of the diamine compound is 1.5% to 3.5%. Specifically, the mass concentration of the diamine compound includes, but is not limited to, 1.5%, 2%, 2.5%, 3%, 3.5%, or a range between any two of the foregoing.

[0058] Without limitation, the diamine compound includes one or more of m-phenylenediamine, p-phenylenediamine and piperazine.

[0059] In some embodiments, the mass concentration of the polyacyl chloride in the oil phase solution of the polyacyl chloride is 0.1% to 0.3%. Specifically, the mass concentration of the polyacyl chloride includes, but is not limited to, 0.1%, 0.12%, 0.14%, 0.16%, 0.18%, 0.2%, 0.22%, 0.24%, 0.26%, 0.28%, 0.3%, or any range therebetween.

[0060] Without limitation, the polyacid chloride includes one or both of trimesoyl chloride and isophthaloyl chloride.

[0061] It is understandable that the solvent used in the aqueous solution of the diamine compound is water, and the solvent used in the oily solution of the polyacyl chloride is an organic solvent immiscible with water, such as one or more of n-heptane, n-hexane and n-decane.

[0062] In some embodiments, the interfacial polymerization reaction time is 6 s to 60 s. Specifically, the time includes but is not limited to: 6 s, 10 s, 15 s, 20 s, 25 s, 30 s, 35 s, 40 s, 45 s, 50 s, 55 s, 60 s, or a range between any two of the foregoing. Furthermore, the interfacial polymerization reaction time is 10 s to 30 s.

[0063] Furthermore, after the interfacial polymerization reaction is completed, one or more of oxidant post-treatment, moisturizing treatment and drying treatment are further included. In some embodiments, after the interfacial polymerization reaction is completed, one or more of oxidant post-treatment, moisturizing treatment and drying treatment are further included.

[0064] In some embodiments, the oxidant post-treatment includes immersing the article after the interfacial polymerization reaction in an aqueous solution of the oxidant for treatment.

[0065] In some embodiments, the mass concentration of the oxidant in the aqueous solution is 50 ppm to 500 ppm. Specifically, the mass concentration of the oxidant includes but is not limited to 50 ppm, 100 ppm, 150 ppm, 200 ppm, 250 ppm, 300 ppm, 350 ppm, 400 ppm, 450 ppm, 500 ppm, or a range between any two of the foregoing.

[0066] In some embodiments, the oxidizing agent includes sodium hypochlorite. Treatment with sodium hypochlorite can effectively remove unreacted monomers and residues.

[0067] In some embodiments, the immersion time in the aqueous solution of the oxidant is 30 seconds to 120 seconds. Specifically, the time includes but is not limited to: 30 seconds, 60 seconds, 90 seconds, 120 seconds, or a range between any two of the foregoing.

[0068] Without limitation, the pH of the aqueous solution of the oxidant is 5-9.

[0069] In some embodiments, the moisturizing treatment includes immersing the article after the oxidant post-treatment in an aqueous solution of a moisturizing agent for treatment.

[0070] In some embodiments, the mass concentration of the moisturizing agent in the aqueous solution is 2% to 20%. Specifically, the mass concentration of the moisturizing agent includes, but is not limited to, 2%, 4%, 6%, 8%, 10%, 12%, 14%, 16%, 18%, 20%, or any range therebetween.

[0071] In some embodiments, the moisturizing agent includes one or both of glycerol and citric acid. Moisturizing treatment with one or both of glycerol and citric acid can reduce water loss during the drying process of the membrane and maintain the stability of the pore structure.

[0072] In some embodiments, the immersion time in the aqueous solution of the moisturizing agent is 10 seconds to 120 seconds. Specifically, the time includes but is not limited to: 10 seconds, 30 seconds, 60 seconds, 90 seconds, 120 seconds, or a range between any two of the foregoing.

[0073] In some embodiments, the drying process includes a temperature of 40°C to 90°C and a drying time of 30 seconds to 180 seconds. Specifically, the temperature includes, but is not limited to, 40°C, 50°C, 60°C, 70°C, 80°C, 90°C, or a range between any two of the foregoing; and the drying time includes, but is not limited to, 30 seconds, 60 seconds, 90 seconds, 120 seconds, 180 seconds, or a range between any two of the foregoing.

[0074] In other embodiments of the present application, a polyamide reverse osmosis membrane is provided, which is prepared by the above-mentioned method for preparing a polyamide reverse osmosis membrane. The polyamide reverse osmosis membrane has high desalination performance and high flux.

[0075] In some embodiments, the permeate flux of the polyamide reverse osmosis membrane is ≥100 L / (m 2 •h). Specifically, the permeation flux includes but is not limited to (L / (m 2 •h)): 100, 110, 120, 120.2, 126.2, 130, 131.5, 140, 150, 160 or a range between any two of the foregoing.

[0076] In some embodiments, the polyamide reverse osmosis membrane has a salt rejection rate of ≥88%. Specifically, the salt rejection rate includes but is not limited to: 88%, 90%, 95%, 98%, 98.1%, 98.3%, 98.5%, 98.6%, or a range therebetween.

[0077] In other embodiments of the present application, there is provided use of the polyamide reverse osmosis membrane described above in water treatment.

[0078] In some other embodiments of the present application, a water treatment method is provided, comprising the following steps:

[0079] The treatment was carried out using the polyamide reverse osmosis membrane as described above.

[0080] In some embodiments, the treatment pressure is ≤1.55 MPa. The polyamide reverse osmosis membrane has a high flux and can achieve effective desalination under relatively low pressure conditions. Specifically, the treatment pressure includes, but is not limited to, 1 MPa, 1.05 MPa, 1.1 MPa, 1.2 MPa, 1.3 MPa, 1.4 MPa, 1.5 MPa, 1.55 MPa, or a range between any two of the foregoing.

[0081] For experimental parameters not specified in the following specific examples, reference is made to the guidance given in this application document, and reference may also be made to experimental manuals in the art or other experimental methods known in the art, or to the experimental conditions recommended by the manufacturer.

[0082] The raw materials and reagents involved in the following specific examples can be obtained from commercial sources, or can be prepared by those skilled in the art according to known methods. The main raw material information is as follows:

[0083] Polysulfone base membrane: P3500 LCD MB7, SOLVAY;

[0084] Rhodamine B: Sigma-Aldrich (Shanghai) Co., Ltd.;

[0085] Metaphenylenediamine: purity 99.9%, Shanghai Annuo Aromatic Amine Chemicals Co., Ltd.

[0086] Trimesoyl chloride: purity >97.5%, Qingdao Sanlibennuo New Materials Co., Ltd.

[0087] n-Heptane: purity 99%, Aladdin Reagent (Shanghai) Co., Ltd.

[0088] Sodium hypochlorite: available chlorine content ≥6%, Wanhua Chlor-Alkali Co., Ltd.;

[0089] Glycerin: purity 99.5%, Shandong Luliya New Materials Co., Ltd.

[0090] Sodium chloride: purity 99.5%, Beijing Yinuokai Technology Co., Ltd.

[0091] Example 1

[0092] This embodiment is a method for preparing a polyamide reverse osmosis membrane, and the steps are as follows:

[0093] (1) Evenly spray 0.02 wt% Rhodamine B aqueous solution on the surface of the polysulfone-based membrane;

[0094] (2) The product of step (1) is fully immersed in a 1.5 wt% aqueous solution of m-phenylenediamine; after taking it out, a 0.12 wt% n-heptane solution of trimesoyl chloride is evenly sprayed on the front of the film to carry out an interfacial polymerization reaction for 20 seconds;

[0095] (3) The reverse osmosis membrane after the reaction in step (2) was post-treated: first immersed in an aqueous solution with a pH of 8 and containing 500 ppm of sodium hypochlorite for 1 minute, then immersed in a 4 wt% glycerol aqueous solution for 30 seconds, and finally dried at 50°C for 2 minutes and rolled up to obtain a polyamide reverse osmosis membrane.

[0096] Example 2

[0097] This embodiment is a method for preparing a polyamide reverse osmosis membrane. The steps are the same as those in Example 1, with the main difference being that the mass concentration of the Rhodamine B aqueous solution in step (1) is 0.05%.

[0098] Example 3

[0099] This embodiment is a method for preparing a polyamide reverse osmosis membrane. The steps are the same as those in Example 1, with the main difference being that the mass concentration of the Rhodamine B aqueous solution in step (1) is 0.1%.

[0100] Example 4

[0101] This embodiment is a method for preparing a polyamide reverse osmosis membrane. The steps are the same as those in Example 1, with the main difference being that an equal amount of m-phenylenediamine is replaced by piperazine, and an equal amount of trimesoyl chloride is replaced by isophthaloyl chloride.

[0102] Example 5

[0103] This embodiment is a method for preparing a polyamide reverse osmosis membrane, and the steps are as follows:

[0104] (1) Spray 0.1 wt% Rhodamine B aqueous solution evenly on the surface of the polysulfone-based membrane and squeeze out the excess solution on the surface;

[0105] (2) The workpiece of step (1) was fully immersed in a 2 wt% aqueous solution of m-phenylenediamine to remove water droplets from the front and back surfaces respectively; then, a 0.2 wt% n-heptane solution of trimesoyl chloride was evenly sprayed on the front of the film to carry out an interfacial polymerization reaction for 8 s;

[0106] (3) The reverse osmosis membrane after the reaction in step (2) was post-treated: first immersed in an aqueous solution with a pH of 8 and containing 100 ppm of sodium hypochlorite for 1 minute, then immersed in a 20 wt% glycerol aqueous solution for 30 seconds, and finally dried at 90°C for 2 minutes and rolled up to obtain a polyamide reverse osmosis membrane.

[0107] Comparative Example 1

[0108] This comparative example is a method for preparing a polyamide reverse osmosis membrane. The steps are the same as those in Example 1, with the main difference being that step (1) is not performed, i.e., Rhodamine B is not applied.

[0109] Comparative Example 2

[0110] This comparative example is a method for preparing a polyamide reverse osmosis membrane, and the steps are as follows:

[0111] (1) The polysulfone-based membrane was fully immersed in a 1.5 wt% m-phenylenediamine aqueous solution to remove water droplets from the front and back surfaces. Then, a 0.12 wt% trimesoyl chloride n-heptane solution was evenly sprayed on the front of the membrane to carry out an interfacial polymerization reaction for 20 s.

[0112] (2) The reverse osmosis membrane after the reaction in step (1) was post-treated by first immersing it in an aqueous solution with a pH of 8 and containing 500 ppm of sodium hypochlorite for 1 minute, then immersing it in a 4 wt% glycerol aqueous solution for 30 seconds, and finally drying it at 50°C for 2 minutes;

[0113] (3) Evenly spraying a 0.02 wt% Rhodamine B aqueous solution on the surface of the dried product in step (2) to obtain a polyamide reverse osmosis membrane.

[0114] Comparative Example 3

[0115] This comparative example is a method for preparing a polyamide reverse osmosis membrane. The steps are the same as those in Example 1, with the main difference being that an equal amount of indole-6-carboxylic acid is used to replace rhodamine B.

[0116] Test example:

[0117] The definition of salt rejection rate R is: under certain operating conditions, the difference between the salt concentration of the feed solution and the salt concentration of the permeate, divided by the salt concentration of the feed solution; the permeate flux F is defined as: under certain operating conditions, the volume of water passing through the unit membrane area per unit time, its unit is L / (m 2 •h).

[0118] The operating conditions are: the inlet liquid is 2000ppm sodium chloride aqueous solution, the operating pressure is 1.05MPa, the operating temperature is 25℃, and the pH of the aqueous solution is 7~8.

[0119] The test results of the salt rejection rate R and flux F of the reverse osmosis membranes prepared in various embodiments and comparative examples are shown in Table 1 below.

[0120] Table 1

[0121]

[0122] The technical features of the above-mentioned embodiments can be combined arbitrarily. In order to make the description concise, not all possible combinations of the technical features in the above-mentioned embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0123] The embodiments described above only express several implementation methods of the present application, which are convenient for understanding the technical solutions of the present application in a specific and detailed manner, but they cannot be understood as limiting the scope of protection of the patent application. It should be pointed out that for ordinary technicians in this field, without departing from the concept of the present application, several variations and improvements can be made, which all fall within the scope of protection of the present application. It should be understood that the technical solutions obtained by those skilled in the art through logical analysis, reasoning or limited experiments on the basis of the technical solutions provided in the present application are all within the scope of protection of the claims attached to the present application. Therefore, the scope of protection of the patent application of this application shall be based on the content of the attached claims, and the description can be used to interpret the content of the claims.

Claims

1. A method for preparing a polyamide reverse osmosis membrane, characterized in that: The steps include: Applying an aqueous solution of Rhodamine B to the base film to prepare a first article; The first component is brought into contact with an aqueous solution of a diamine compound and an oily solution of a polyacid chloride, and an interfacial polymerization reaction is performed on the first component to prepare a polyamide reverse osmosis membrane.

2. The method for preparing a polyamide reverse osmosis membrane according to claim 1, wherein In the aqueous solution of Rhodamine B, the mass concentration of Rhodamine B is 0.01% to 0.1%.

3. The method for preparing a polyamide reverse osmosis membrane according to claim 1, wherein The step of contacting the first article with an aqueous solution of a diamine compound and an oily solution of a polyacid chloride comprises: immersing the first article in the aqueous solution of the diamine compound, taking it out, and preparing a second article; The oil phase solution of the polyacid chloride is sprayed on one side of the second component.

4. The method for preparing a polyamide reverse osmosis membrane according to claim 1, wherein In the aqueous solution of the diamine compound, the mass concentration of the diamine compound is 1.5% to 3.5%; and / or, In the oil phase solution of the polyacid chloride, the mass concentration of the polyacid chloride is 0.1% to 0.3%.

5. The method for preparing a polyamide reverse osmosis membrane according to claim 1, wherein The diamine compound includes one or more of m-phenylenediamine, p-phenylenediamine and piperazine; and / or, The polyacid chloride includes one or both of trimesoyl chloride and isophthaloyl chloride.

6. The method for preparing a polyamide reverse osmosis membrane according to any one of claims 1 to 5, wherein: The time of the interfacial polymerization reaction is 6s~60s, and can be optionally 10s~30s.

7. The method for preparing a polyamide reverse osmosis membrane according to any one of claims 1 to 5, wherein: After the interfacial polymerization reaction is completed, it also includes oxidant post-treatment, moisturizing treatment and drying treatment; Optionally, the oxidant post-treatment includes: immersing the workpiece after the interfacial polymerization reaction in an aqueous solution of the oxidant for treatment; Further optionally, in the aqueous solution of the oxidant, the mass concentration of the oxidant is 50 ppm to 500 ppm; Further optionally, the oxidant comprises sodium hypochlorite; Further optionally, the time for immersing in the aqueous solution of the oxidant for treatment is 30s to 120s; Optionally, the moisturizing treatment includes: immersing the workpiece after the oxidant post-treatment in an aqueous solution of a moisturizing agent for treatment; Further optionally, in the aqueous solution of the moisturizing agent, the mass concentration of the moisturizing agent is 2% to 20%; Further optionally, the moisturizing agent includes one or both of glycerin and citric acid; Further optionally, the time for immersing in the aqueous solution of the moisturizing agent for treatment is 10s to 120s; Optionally, the drying conditions include: a temperature of 40° C. to 90° C. and a time of 30 seconds to 180 seconds.

8. A polyamide reverse osmosis membrane, characterized in that Prepared by the preparation method of the polyamide reverse osmosis membrane according to any one of claims 1 to 7; Optionally, the permeate flux of the polyamide reverse osmosis membrane is ≥100 L / (m 2 •h); Optionally, the polyamide reverse osmosis membrane has a salt rejection rate of ≥88%.

9. Use of the polyamide reverse osmosis membrane according to claim 8 in water treatment.

10. A water treatment method, characterized in that: The steps include: The polyamide reverse osmosis membrane according to claim 8 is used for treatment; Optionally, the treatment pressure is ≤1.55 MPa.

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