Polyamide reverse osmosis membrane with high desalination rate and preparation method thereof

Abstract

The application provides a high desalination rate polyamide reverse osmosis membrane and a preparation method thereof, and the method comprises the following steps: coating a water phase solution on a polysulfone support layer, then coating an oil phase solution, drying, and obtaining a nascent polyamide reverse osmosis membrane; rinsing the nascent polyamide reverse osmosis membrane, then immersing the nascent polyamide reverse osmosis membrane in a post-treatment solution, air-drying, and obtaining a high desalination rate polyamide reverse osmosis membrane; the post-treatment solution is a four-arm polyethylene glycol glycidyl ether aqueous solution. The four-arm polyethylene glycol glycidyl ether aqueous solution is used as the post-treatment solution, the crosslinking degree of the polyamide separation layer can be increased, and thus the desalination rate of the membrane is improved; in addition, the concentration of the four-arm polyethylene glycol glycidyl ether aqueous solution and the immersion time or multiple immersions can be adjusted, and the flux and the desalination rate of the membrane can be effectively controlled.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of reverse osmosis membranes, and particularly relates to a high-desalination-rate polyamide reverse osmosis membrane and a preparation method thereof. BACKGROUND

[0002] Reverse osmosis technology is an advanced and energy-efficient separation technology today. Its principle is that under the action of a pressure higher than the osmotic pressure of a solution, the solute and solvent in the solution are separated by the selective interception of a semi-permeable membrane that allows only water to pass through but not other substances. By utilizing the separation characteristics of the reverse osmosis membrane, the dissolved salts, colloids, organic matter, bacteria, microorganisms and other impurities in water can be effectively removed. Reverse osmosis technology has the advantages of low energy consumption, no pollution, advanced process, simple operation and maintenance, etc. The reverse osmosis membrane is the core of the reverse osmosis technology, and the research and application of the reverse osmosis membrane has always been the hottest research direction in the field of reverse osmosis technology.

[0003] Chinese patent CN 106512729 A introduces a preparation method of a high-desalination-rate composite reverse osmosis membrane: by utilizing the characteristic that aromatic polyamide molecules are easy to hydrolyze in an acidic solution, the reverse osmosis composite membrane is first appropriately hydrolyzed under acidic conditions to obtain a relatively loose polyamide separation layer, then the separation layer is used as a support structure, and a thinner and denser functional layer is deposited on the surface of the separation layer as a separation layer by means of solvent evaporation and chemical crosslinking, so that the desalination rate of the reverse osmosis composite membrane is improved without sacrificing the permeation flux. However, the degree of hydrolysis is difficult to control when the reverse osmosis composite membrane is appropriately hydrolyzed under acidic conditions, and in addition, the step of depositing a thinner and denser functional layer on the surface of the reverse osmosis composite membrane by means of solvent evaporation and chemical crosslinking is relatively cumbersome and is not conducive to industrial production. SUMMARY

[0004] Therefore, the purpose of the present application is to provide a high-desalination-rate polyamide reverse osmosis membrane and a preparation method thereof. The method is simple, and the prepared polyamide reverse osmosis membrane has a high flux and a high desalination rate.

[0005] The present application provides a preparation method of a high-desalination-rate polyamide reverse osmosis membrane, comprising the following steps:

[0006] Coating a water-phase solution on a polysulfone support layer, then coating an oil-phase solution, drying to obtain a nascent polyamide reverse osmosis membrane;

[0007] Rinsing the nascent polyamide reverse osmosis membrane, then immersing it in a post-treatment solution, air-drying to obtain a high-flux high-desalination-rate anti-pollution polyamide reverse osmosis membrane;

[0008] The post-treatment solution is a four-arm polyethylene glycol glycidyl ether aqueous solution.

[0009] The application can increase the cross-linking degree of the polyamide separation layer, thereby improving the desalination rate of the membrane, by using the four-arm polyethylene glycol glycidyl ether aqueous solution as the post-processing solution; in addition, the concentration and soaking time or multiple soaking of the four-arm polyethylene glycol glycidyl ether aqueous solution can be adjusted to effectively control the flux and desalination rate of the membrane.

[0010] The application coats a water phase solution on a polysulfone support layer, coats an oil phase solution, and dries to obtain a nascent polyamide reverse osmosis membrane.

[0011] In the application, the water phase solution comprises 0.5-5wt% multifunctional amine, 0.05-2wt% surfactant, 3-10wt% polar solvent, sodium hydroxide, and the balance water; the sodium hydroxide adjusts the pH value of the water phase solution to 7-9. In the application, the water phase solution comprises 0.5-5wt% multifunctional amine, preferably 2.0-3.0wt%; the multifunctional amine is selected from any one or more of m-phenylenediamine, ethylenediamine, propylenediamine, butylenediamine, hexylenediamine, N-(2-hydroxyethyl)ethylenediamine, 1,2-diaminocyclohexane, 1,3-diaminocyclohexane, 1,4-diaminocyclohexane, diethylenetriamine, m-phenylenediamine, p-phenylenediamine, o-phenylenediamine, m-phenylenediamine, piperazine, and 4-aminomethylpiperazine. The water phase solution comprises 0.05-2wt% surfactant, preferably 0.05-0.15wt%; the surfactant is selected from sodium dodecylbenzenesulfonate and / or sodium laurylsulfate. The water phase solution comprises 3-10wt% polar solvent, preferably 5-8wt%; the polar solvent is selected from dimethyl sulfoxide and / or N-methylpyrrolidone.

[0012] The application first coats a water phase solution on a polysulfone support layer, removes the excess solution on the surface, and then passes the polysulfone base film adsorbed with the water phase solution through a closed space with a heat supply and air exhaust system, preferably volatilizes the water content of the water phase solution to 28-35% at 20-30℃ and 40-80% relative humidity after coating the water phase solution, and then coats an oil phase solution. In the application, the oil phase solution comprises 0.05-0.3wt% multifunctional acyl halide, and the balance is an oil phase solvent; the oil phase solvent is selected from one of C4-C12 aliphatic hydrocarbon, cycloaliphatic hydrocarbon, and aromatic hydrocarbon. The application preferably removes a part of the oil phase solution on the surface after coating the oil phase solution, and then enters a 60-80℃ oven to dry, to form a polyamide ultra-thin separation layer, i.e. to obtain a nascent polyamide reverse osmosis membrane.

[0013] After obtaining the nascent polyamide reverse osmosis membrane, the application rinses the nascent polyamide reverse osmosis membrane, soaks in a post-processing solution, and air dries, to obtain a polyamide reverse osmosis membrane with high desalination rate.

[0014] In the application, the rinsing specifically comprises:

[0015] The nascent polyamide reverse osmosis membrane is rinsed with inorganic strong alkali aqueous solution, isopropyl alcohol aqueous solution and water in sequence; the concentration of the inorganic strong alkali aqueous solution is 0.004-0.04wt%, preferably 0.01-0.04wt%; the inorganic strong alkali aqueous solution is sodium hydroxide aqueous solution or potassium hydroxide aqueous solution. The concentration of the isopropyl alcohol aqueous solution is 5-25wt%, preferably 10-20wt%.

[0016] The present application can greatly improve the flux of the reverse osmosis membrane by using the polar solvent and the alkaline solution with high concentration for rinsing, and further improve the flux of the nascent polyamide reverse osmosis membrane by using the isopropyl alcohol aqueous solution with high concentration for rinsing.

[0017] In the present application, the post-treatment solution is four-arm polyethylene glycol glycidyl ether aqueous solution; the molecular weight of the four-arm polyethylene glycol glycidyl ether is 2000-5000g / mol; the concentration of the four-arm polyethylene glycol glycidyl ether aqueous solution is 0.01-1wt%. The temperature of the soaking in the post-treatment solution is 10-40℃, and the time is 10-60min.

[0018] The soaking in the post-treatment solution can prolong the soaking time or can be divided into multiple times of soaking.

[0019] The following test method is used in the present application to test the performance of the reverse osmosis membrane:

[0020] The initial flux and the desalination rate of the polyamide reverse osmosis membrane with high desalination rate are tested by filtering 1500ppm sodium chloride aqueous solution at 1.03MPa, 25℃ and the membrane surface flow rate of 1.1GPM / min for 30min.

[0021] The present application provides a preparation method of polyamide reverse osmosis membrane with high desalination rate, which comprises the following steps: coating water phase solution on the polysulfone support layer, then coating oil phase solution, drying to obtain nascent polyamide reverse osmosis membrane; rinsing the nascent polyamide reverse osmosis membrane, then soaking in post-treatment solution, and air-drying to obtain polyamide reverse osmosis membrane with high desalination rate; the post-treatment solution is four-arm polyethylene glycol glycidyl ether aqueous solution. The present application uses four-arm polyethylene glycol glycidyl ether aqueous solution as the post-treatment solution, which can increase the crosslinking degree of the polyamide separation layer, thereby improving the desalination rate of the membrane; in addition, the present application can adjust the concentration of the four-arm polyethylene glycol glycidyl ether aqueous solution and the soaking time or multiple times of soaking, thereby effectively controlling the flux and the desalination rate of the membrane. DETAILED DESCRIPTION

[0022] In order to further illustrate the present application, a high desalination rate polyamide reverse osmosis membrane and a preparation method thereof provided by the present application are described in detail below in conjunction with examples, but they should not be understood as limiting the protection scope of the present application.

[0023] Comparative Example 1

[0024] A production method of the high desalination rate polyamide reverse osmosis membrane is as follows:

[0025] 1. Preparation of the water phase solution: 25 g of m-phenylenediamine, 1 g of sodium dodecyl sulfate and 80 g of N-methylpyrrolidone were dissolved in 894 g of water, and the pH value was adjusted to 8.5-9 using sodium hydroxide. After stirring uniformly, the water phase solution was obtained.

[0026] 2. Preparation of the oil phase solution: 2.5 g of trimesoyl chloride was dissolved in 997.5 g of Isopar G, and the oil phase solution was obtained after stirring uniformly.

[0027] 3. The water phase solution was first coated on the polysulfone support layer. After removing the excess solution on the surface, the polysulfone substrate film adsorbed with the water phase solution was passed through a closed space with a heat supply and air exhaust system, and the internal temperature was controlled at 20-30°C and the relative humidity was controlled at 40%-80%, so that the water content of the membrane surface was further volatilized to 28-35 wt%. Then, the oil phase solution was coated on the surface, and after removing a part of the oil phase solution on the surface, it was then dried in an oven at 60-80°C to form a polyamide ultra-thin separation layer, thereby obtaining a nascent polyamide reverse osmosis membrane.

[0028] 4. The initial flux and desalination rate of the high desalination rate polyamide reverse osmosis membrane were tested by filtering a 1500 ppm sodium chloride aqueous solution at 1.03 MPa, 25°C and a membrane surface flow rate of 1.1 GPM / min for 30 min. All the test results are shown in Table 1.

[0029] Comparative Example 2

[0030] A production method of the high desalination rate polyamide reverse osmosis membrane is as follows:

[0031] 1. The same as Comparative Example 1.

[0032] 2. The same as Comparative Example 1.

[0033] 3. Preparation of rinse solution 1: 4 g of sodium hydroxide was dissolved in 2 L of water to obtain rinse solution 1.

[0034] 4. Preparation of rinse solution 2: 400 g of IPA was dissolved in 2 L of water to obtain rinse solution 2.

[0035] 5. First, the water phase solution is coated on the polysulfone support layer. After removing the excess solution on the surface, the polysulfone bottom film adsorbing the water phase solution is passed through a closed space with a heat supply and air exhaust system, the internal temperature is controlled at 20-30°C, the relative humidity is controlled at 40-80%, and the water content on the film surface is further volatilized to 28-35 wt%. Then, the oil phase solution is coated on the film. After removing a part of the oil phase solution on the surface, the film is dried in an oven at 60-80°C to form a polyamide ultra-thin separation layer. The polyamide reverse osmosis membrane in nascent state is obtained after the film is immersed and rinsed with rinsing liquid 1 and rinsing liquid 2 in turn and dried.

[0036] 6. The initial flux and desalination rate of the polyamide reverse osmosis membrane with high desalination rate are tested by filtering 1500 ppm sodium chloride aqueous solution at 1.03 MPa, 25°C and a flow rate of 1.1 GPM / min for 30 min. All the test results are shown in Table 1.

[0037] Comparative Example 3:

[0038] A method for producing a polyamide reverse osmosis membrane with high desalination rate is as follows:

[0039] 1. The same as Comparative Example 1.

[0040] 2. The same as Comparative Example 1.

[0041] 3. The same as Comparative Example 2.

[0042] 4. The same as Comparative Example 2.

[0043] 5. Preparation of the post-treatment solution: 2 g of polyethylene glycol diglycidyl ether with a molecular weight of 2000 is dissolved in 998 g of water to obtain the post-treatment solution.

[0044] 6. First, the water phase solution is coated on the polysulfone support layer. After removing the excess solution on the surface, the polysulfone bottom film adsorbing the water phase solution is passed through a closed space with a heat supply and air exhaust system, the internal temperature is controlled at 20-30°C, the relative humidity is controlled at 40-80%, and the water content on the film surface is further volatilized to 28-35 wt%. Then, the oil phase solution is coated on the film. After removing a part of the oil phase solution on the surface, the film is dried in an oven at 60-80°C to form a polyamide ultra-thin separation layer. The polyamide reverse osmosis membrane in nascent state is obtained after the film is immersed and rinsed with rinsing liquid 1 and rinsing liquid 2 in turn and dried.

[0045] 7. The initial flux and desalination rate of the polyamide reverse osmosis membrane with high desalination rate are tested by filtering 1500 ppm sodium chloride aqueous solution at 1.03 MPa, 25°C and a flow rate of 1.1 GPM / min for 30 min. All the test results are shown in Table 1.

[0046] Comparative Example 4:

[0047] A method for producing a high desalination rate polyamide reverse osmosis membrane is as follows:

[0048] 1. Same as Comparative Example 1.

[0049] 2. Same as Comparative Example 1.

[0050] 3. Same as Comparative Example 2.

[0051] 4. Same as Comparative Example 2.

[0052] 5. Preparation of post-treatment solution: weigh 2 g of eight-arm polyethylene glycol glycidyl ether with a molecular weight of 10,000 into 998 g of water to obtain the post-treatment solution.

[0053] 6. First, coat the polysulfone support layer with the aqueous phase solution, remove the excess solution on the surface, and then pass the polysulfone substrate film adsorbed with the aqueous phase solution through a closed space with a heat supply and exhaust system, control the internal temperature at 20-30°C and the relative humidity at 40-80%, and let the water content on the membrane surface further volatilize to 28-35 wt%. Then, coat the oil phase solution on it, remove part of the oil phase solution on the surface, and then enter the 60-80°C oven for drying to form a polyamide ultra-thin separation layer. After soaking and rinsing with rinsing liquid 1 and rinsing liquid 2 in turn, the post-treatment solution is soaked for 40 min, and then dried to obtain a high desalination rate polyamide reverse osmosis membrane.

[0054] 7. At 1.03 MPa, 25°C and a membrane surface flow rate of 1.1 GPM / min, filter 1500 ppm sodium chloride aqueous solution for 30 min, and test the initial flux and desalination rate of the high desalination rate polyamide reverse osmosis membrane. All test results are shown in Table 1.

[0055] Example 1:

[0056] A method for producing a high desalination rate polyamide reverse osmosis membrane is as follows:

[0057] 1. Same as Comparative Example 1.

[0058] 2. Same as Comparative Example 1.

[0059] 3. Same as Comparative Example 2.

[0060] 4. Same as Comparative Example 2.

[0061] 5. Preparation of post-treatment solution: weigh 2 g of four-arm polyethylene glycol glycidyl ether with a molecular weight of 2000 into 998 g of water to obtain the post-treatment solution.

[0062] 6. First, the water phase solution is coated on the polysulfone support layer. After removing the excess solution on the surface, the polysulfone bottom film with the water phase solution adsorbed is passed through a closed space with a heating and air exhaust system, the internal temperature is controlled at 20-30°C, the relative humidity is controlled at 40-80%, and the water content on the film surface is further volatilized to 28-35 wt%. Then, the oil phase solution is coated on the film, after removing a part of the oil phase solution on the surface, the film is dried in an oven at 60-80°C to form a polyamide ultra-thin separation layer. The polyamide reverse osmosis membrane with high desalination rate is obtained after the film is immersed in rinsing liquid 1, rinsing liquid 2, and then the grafting post-treatment solution for 40 min, and air drying.

[0063] 7. The initial flux and desalination rate of the polyamide reverse osmosis membrane with high desalination rate are tested by filtering 1500 ppm sodium chloride aqueous solution at 1.03 MPa, 25°C, and a film surface flow rate of 1.1 GPM / min for 30 min. All the test results are shown in Table 1.

[0064] Example 2:

[0065] A method for producing a polyamide reverse osmosis membrane with high flux and high desalination rate is as follows:

[0066] 1. Same as Comparative Example 1.

[0067] 2. Same as Comparative Example 1.

[0068] 3. Same as Comparative Example 2.

[0069] 4. Same as Comparative Example 2.

[0070] 5. Preparation of the grafting post-treatment solution: 6 g of four-arm polyethylene glycol glycidyl ether with a molecular weight of 2000 is selected and dissolved in 994 g of water to obtain the grafting post-treatment solution.

[0071] 6. Same as Example 1.

[0072] 7. Same as Example 1.

[0073] Example 3:

[0074] A method for producing a polyamide reverse osmosis membrane with high flux and high desalination rate is as follows:

[0075] 1. Same as Comparative Example 1.

[0076] 2. Same as Comparative Example 1.

[0077] 3. Same as Comparative Example 2.

[0078] 4. Same as Comparative Example 2.

[0079] 5. Preparation of grafting post-treatment solution: 10 g of four-arm polyethylene glycol glycidyl ether with molecular weight of 2000 was selected in 994 g of water to obtain the grafting post-treatment solution;

[0080] 6. The same as Example 1.

[0081] 7. The same as Example 1.

[0082] Example 4:

[0083] A production method of a high-flux high-desalination-rate polyamide reverse osmosis membrane is as follows:

[0084] 1. The same as Comparative Example 1.

[0085] 2. The same as Comparative Example 1.

[0086] 3. The same as Comparative Example 2.

[0087] 4. The same as Comparative Example 2.

[0088] 5. The same as Example 2;

[0089] 6. First, a water-phase solution is coated on the polysulfone support layer, after removing the excess solution on the surface, the polysulfone substrate film adsorbed with the water-phase solution is passed through a closed space with a heat supply and air exhaust system, the internal temperature is controlled at 20-30℃, the relative humidity is controlled at 40-80%, the water content on the membrane surface is further volatilized to 28-35 wt%. Then, an oil-phase solution is coated on it, after removing a part of the oil-phase solution on the surface, it is then passed into an oven at 60-80℃ for drying, forming a polyamide ultra-thin separation layer, after sequentially immersing and rinsing it with rinsing liquid 1 and rinsing liquid 2, it is immersed in the grafting post-treatment solution for 10 min, and then air-dried, obtaining a high-flux high-desalination-rate polyamide reverse osmosis membrane.

[0090] 7. The same as Example 1.

[0091] Example 5:

[0092] A production method of a high-flux high-desalination-rate polyamide reverse osmosis membrane is as follows:

[0093] 1. The same as Comparative Example 1.

[0094] 2. The same as Comparative Example 1.

[0095] 3. The same as Comparative Example 2.

[0096] 4. The same as Comparative Example 2.

[0097] 5. The same as Example 2;

[0098] 6. First, the water phase solution is coated on the polysulfone support layer. After removing the excess solution on the surface, the polysulfone bottom film adsorbing the water phase solution is passed through a closed space with a heat supply and air exhaust system, the internal temperature is controlled at 20-30°C, the relative humidity is controlled at 40-80%, and the water content on the film surface is further volatilized to 28-35 wt%. Then, the oil phase solution is coated on the film. After removing a part of the oil phase solution on the surface, the film is dried in an oven at 60-80°C to form a polyamide ultra-thin separation layer. The polyamide reverse osmosis membrane with high desalination rate is obtained after the film is immersed in rinsing liquid 1, rinsing liquid 2, and grafting post-treatment solution in sequence, and dried.

[0099] 7. Same as Example 1.

[0100] Example 6:

[0101] A method for producing a polyamide reverse osmosis membrane with high flux and high desalination rate is as follows:

[0102] 1. Same as Example 1.

[0103] 2. Same as Example 1.

[0104] 3. Same as Comparative Example 2.

[0105] 4. Same as Comparative Example 2.

[0106] 5. Same as Example 2.

[0107] 6. First, the water phase solution is coated on the polysulfone support layer. After removing the excess solution on the surface, the polysulfone bottom film adsorbing the water phase solution is passed through a closed space with a heat supply and air exhaust system, the internal temperature is controlled at 20-30°C, the relative humidity is controlled at 40-80%, and the water content on the film surface is further volatilized to 28-35 wt%. Then, the oil phase solution is coated on the film. After removing a part of the oil phase solution on the surface, the film is dried in an oven at 60-80°C to form a polyamide ultra-thin separation layer. The polyamide reverse osmosis membrane with high desalination rate is obtained after the film is immersed in rinsing liquid 1, rinsing liquid 2, and grafting post-treatment solution in sequence, and dried.

[0108] 7. Same as Example 1.

[0109] Table 1: Initial flux and desalination rate of polyamide reverse osmosis membranes prepared in Examples and Comparative Examples

[0110]

[0111] In Table 1, the desalination rate = (1- product water conductivity / feed water conductivity) * 100%;

[0112] The lower the water conductivity is, the lower the salt concentration in the produced water is, and the better the water quality is; the water quality of Example 1 is greatly improved without loss of flux compared with Comparative Example 3.

[0113] From the above examples, it is known that, when the composite polyamide reverse osmosis membrane is prepared by the interfacial polymerization method, the addition of the polar solvent in the water phase liquid is beneficial to increase the specific surface area of the polyamide layer, thereby improving the flux, and the use of the alkaline solution for rinsing can make the amide bond of the polyamide hydrolyze, thereby improving the flux, and the use of the IPA for rinsing can make the composite polyamide reverse osmosis membrane swell, and the flux can be further improved, but these methods can improve the flux while causing the desalination rate to decrease. The four-arm polyethylene glycol glycidyl ether can greatly improve the crosslinking degree of the separation layer on the surface of the composite polyamide reverse osmosis membrane, thereby greatly improving the desalination rate. The experimental results show that the flux of the polyamide reverse osmosis membrane obtained by the method provided in the application is 52.1-59.5 GFD, the desalination rate is 99.21-99.56%, and the water conductivity is 14.67-23.01 μS / cm.

[0114] The above only describes the preferred embodiments of the present application, and it should be noted that, for those skilled in the art, some improvements and refinements can be made without departing from the principles of the present application, and these improvements and refinements should also be considered as the protection scope of the present application.

Claims

1. A method for preparing a polyamide reverse osmosis membrane with high desalination rate, comprising the following steps: coating a water phase solution on a polysulfone support layer, then coating an oil phase solution, drying to obtain a nascent polyamide reverse osmosis membrane; rinsing the nascent polyamide reverse osmosis membrane, then immersing in a post-treatment solution, air-drying to obtain a polyamide reverse osmosis membrane with high desalination rate; wherein the rinsing specifically comprises: rinsing the nascent polyamide reverse osmosis membrane with inorganic strong alkali aqueous solution, isopropyl alcohol aqueous solution and water in sequence; the concentration of the inorganic strong alkali aqueous solution is 0.004-0.04wt%; the concentration of the isopropyl alcohol aqueous solution is 5-25wt%; wherein the post-treatment solution is a four-arm polyethylene glycol glycidyl ether aqueous solution; the molecular weight of the four-arm polyethylene glycol glycidyl ether is 2000-5000; the concentration of the four-arm polyethylene glycol glycidyl ether aqueous solution is 0.01-1wt%; the temperature for immersing in the post-treatment solution is 10-40℃, and the time is 10-80min. The water phase solution comprises 0.5-5wt% multifunctional amine, 0.05-2wt% surfactant, 3-10wt% dimethyl sulfoxide and / or N-methyl pyrrolidone, sodium hydroxide and the rest water; the sodium hydroxide adjusts the pH value of the water phase solution to 7-9. The oil phase solution comprises 0.05-0.3% multifunctional acyl halide, and the rest is an oil phase solvent; the oil phase solvent is selected from one of C4-C12 aliphatic hydrocarbon and aromatic hydrocarbon. The multifunctional amine is selected from any one or more of m-phenylenediamine, ethylenediamine, propylenediamine, butylenediamine, hexylenediamine, N-(2-hydroxyethyl)ethylenediamine, 1,2-diaminocyclohexane, 1,3-diaminocyclohexane, 1,4-diaminocyclohexane, diethylenetriamine, p-phenylenediamine, o-phenylenediamine, m-phenylenediamine, piperazine and 4-aminomethylpiperazine. The surfactant is selected from sodium dodecyl benzene sulfonate and / or sodium lauryl sulfate. The coating of the water phase solution is followed by volatilization at 20-30℃ and relative humidity of 40-80% to a water content of 28-35%, and then coating of the oil phase solution.

2. The production method according to claim 1, characterized by, 5.A polyamide reverse osmosis membrane with high desalination rate, prepared by the method of any one of claims 1-4. ​ 3. The preparation method according to claim 2, characterized in that, ​ ​ 4. The method of claim 1, wherein, ​ ​

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