KR20130037365A - Reverse osmosis membrane having a high fouling resistance and manufacturing method thereof - Google Patents

Abstract

PURPOSE: A reverse osmosis membrane with an excellent contamination resistance and a manufacturing method thereof are provided to prevent a fouling phenomenon that is a phenomenon of which an amount of water penetration or a water penetrating property, such as a salt removing rate, are deteriorated in time as the membrane is contaminated. CONSTITUTION: A reverse osmosis membrane with an excellent contamination resistance comprises a fine porous supporting member(100), an active layer(200), an ionic polymer layer(300), and a coating layer(400). The active layer is formed on the fine porous supporting member. The ionic polymer layer is formed on the fine porous supporting member. The coating layer is formed on the ionic polymer layer and comprises optical catalyst nanoparticles.

Description

Reverse osmosis membrane with excellent fouling resistance and manufacturing method {REVERSE OSMOSIS MEMBRANE HAVING A HIGH FOULING RESISTANCE AND MANUFACTURING METHOD THEREOF}

The present invention relates to a reverse osmosis membrane and a method for manufacturing the same, and more particularly, to a reverse osmosis membrane and a method for manufacturing the same by improving the surface characteristics by modifying the surface properties.

The phenomenon that the solvent moves between the two solutions separated by the semi-permeable membrane through the membrane from the solution with a low solute concentration to the solution with a high solute concentration is called osmotic phenomenon. The pressure acting on the solution side Is called osmotic pressure. However, when an external pressure higher than osmotic pressure is applied, the solvent moves toward the solution having a low solute concentration. This phenomenon is called reverse osmosis. By using the reverse osmosis principle, it is possible to separate various salts or organic substances through the semipermeable membrane using the pressure gradient as a driving force. Reverse osmosis membranes using the reverse osmosis phenomenon are used in various fields such as desalination of seawater, wastewater treatment, ultrapure water production, household water treatment, etc. by separating substances at molecular level and removing salts from salt water or seawater. The study of the reverse osmosis field was mainly aimed at increasing the permeability of the membrane and improving the salt removal rate.

However, in a water treatment process using a reverse osmosis membrane, fouling is a phenomenon in which a solute or an ionic compound is adsorbed on the surface of the membrane and contaminates the membrane. As fouling occurs, most of the operating costs of water treatment facilities are being used to prevent fouling and fouling due to fouling, and research on fundamental preventive measures is required.

Generally, the causative agent causing fouling is divided into inorganic crystalline fouling, organic fouling, particle and colloid fouling, and microbial fouling depending on the form. In the case of polyamide reverse osmosis composite membranes, microbial fouling generated by adsorption of microorganisms in water onto the membrane surface is known to be the most serious.

In order to reduce fouling, methods such as pretreatment of raw water, modification of the electrical properties of the membrane surface, modification of the process condition of the membrane, and periodic cleaning are widely used. In particular, in the case of fouling caused by microorganisms most seriously occurred in the reverse osmosis composite membrane, fouling caused by microorganisms is reduced by treatment with a fungicide such as chlorine. However, since chlorine generates by-products such as carcinogens, there are many problems to be applied to the process of producing drinking water.

On the other hand, recently, a method of dispersing metal oxide particles such as titanium dioxide, that is, a photocatalyst having a characteristic of disinfecting microorganisms under ultraviolet light or sunlight and dispersing organic substances, or dispersing it in water during a water treatment process or on the surface of a separator is proposed. However, the process of adding such metal oxide particles to water requires a secondary process of recovering the particles again, and it is difficult to recycle the particles. Also, when the metal oxide particles are dispersed on the surface of the separator, the separator Due to the roughness of the surface and the roughness of the surface of the separator, there is a problem that the metal oxide particles are difficult to uniformly and uniformly coat because the charge or the functional groups induced on the surface of the separator are not induced evenly.

The present invention is to solve the above problems, and provides a reverse osmosis membrane and a manufacturing method excellent in fouling resistance.

To this end, the present invention is a microporous support; An activation layer formed on the microporous support; An ionic polymer layer formed on the activation layer; And it is formed on the ionic polymer layer, and provides a reverse osmosis membrane excellent in fouling resistance comprising a coating layer comprising a photocatalytic nanoparticles.

In another aspect, the present invention comprises the steps of (a) preparing a microporous support; (b) forming an activation layer on the microporous support; (c) forming an ionic polymer layer on the activation layer; And (d) forming a coating layer including photocatalytic nanoparticles on the ionic polymer layer.

Reverse osmosis membrane according to the present invention, while maintaining the same or superior permeate flow rate and salt removal rate compared to the conventional membrane, photolysis of the pollutant present in the water to prevent them from adsorbed to the membrane, the membrane is contaminated over time As a result, fouling, which is a phenomenon in which water permeation characteristics such as water permeation amount and salt removal rate, are lowered, can be prevented.

1 is a view schematically showing the structure of a reverse osmosis membrane according to an embodiment of the present invention.

Hereinafter, the present invention will be described in more detail with reference to the drawings.

Figure 1 schematically shows the structure of the reverse osmosis membrane according to an embodiment of the present invention. As shown in FIG. 1, the reverse osmosis membrane according to one embodiment of the present invention includes a microporous support 100, an activation layer 200, an ionic polymer layer 300, and a coating layer 400.

Here, the microporous support 100 may be a polymer material cast on a nonwoven fabric, the nonwoven material, for example, polyester, polycarbonate, microporous polypropylene, polyphenylene ether, polyvinyl fluoride Leeden and the like can be used, but is not necessarily limited thereto. However, among these, polyester is particularly preferable. In addition, as the polymer material, for example, polysulfone, polyethersulfone, polycarbonate, polyethylene oxide, polyimide, polyetherimide, polyetheretherketone, polypropylene, polymethylpentene, polymethyl chloride and polyvinyl Regenzlide and the like can be used, but are not necessarily limited to these. Of these, polysulfone is particularly preferable.

On the other hand, the thickness of the microporous support 100 is preferably 100 ~ 200㎛, more preferably 120 ~ 170㎛, most preferably 140 ~ 150㎛. If the thickness of the porous support is thinner than 100 μm, the membrane may be damaged because it cannot withstand the high pressure applied during the operation of the water treatment membrane. If the thickness of the porous support is greater than 200 μm, the surface roughness may be increased. This is because the performance of the membrane is likely to be deteriorated in that the exit path is long.

In addition, the pore size of the microporous support 100 is preferably 10 to 70nm. This is because it is an effective range for selectively separating suspended substances, polysaccharides, proteins, and polymeric substances, which are generally known as substances capable of being separated from a porous support.

Next, the activation layer 200 is formed on the microporous support 100, and performs a function of excluding salt. The activation layer 200 may be, for example, polyamide, replaceable polyamide, polypiperazine, replaceable polypiperazine, polyphenylene diamine, replaceable polyphenyldiamine, polychloro phenylene diamine, and replaceable poly. It may consist of chloro phenylene diamine, polybenzidine, substituted polybenzidine, and the like, although not necessarily limited thereto, of which polyamide is particularly preferred.

Meanwhile, the thickness of the activation layer 200 is preferably 100 to 200 nm, more preferably 110 to 180 nm, and most preferably 130 to 150 nm. Since the activation layer is very rough, if the thickness of the activation layer is less than 100nm, it is highly unlikely to coat the entire porous support, and if the thickness of the activation layer is more than 200nm, the activation layer is likely to be unevenly formed. to be.

Next, the ionic polymer layer 300 is formed on the activation layer 200, and can improve the salt rejection rate by salt ions and electrostatic repulsion, and according to the charge distribution of the ionic polymer layer. The photocatalytic nanoparticles of the coating layer 400 formed on the polymer layer 300 may be widely and uniformly distributed. If the ionic polymer layer does not exist, the functional groups of the activating layer alone do not induce charges evenly on the surface of the membrane, and thus the photocatalytic nanoparticles are not evenly adsorbed. May adversely affect

On the other hand, the ionic polymer layer 300 is preferably 1 to 10nm in thickness. This is because when the thickness of the ionic polymer layer is 1 nm or less, it is difficult to uniformly induce charges on the coated surface. When the thickness of the ionic polymer layer is more than 10 nm, the thickness is too thick, which may adversely affect the membrane performance. In addition, more specifically, the thickness of the ionic polymer layer 300 is more preferably 2 to 8nm, most preferably 3 to 6nm. This means that the photocatalytic nanoparticles formed on the ionic polymer layer 300 can be more broadly and uniformly distributed without being deteriorated when the ionic polymer layer is coated with the thickness in the above range, This is because the salt rejection rate is also excellent.

Meanwhile, the ionic polymer layer 300 has a structure in which a cationic polymer membrane and an anionic polymer membrane are sequentially stacked. The number of the cationic polymer film and the anion polymer film formed on the activation layer 200 is not particularly limited, but the polymer film formed on the activation layer 200 should have an ionic property in which the electrostatic attraction works with the activation layer 200. In addition, the polymer film formed under the coating layer 400 should have an ionic property in which the coating layer 400 and the electrostatic attraction work. Specifically, for example, when the charge characteristic of the activation layer 200 is an anion, a cationic polymer film in which the activating layer 200 and the electrostatic attraction work is formed on the activation layer 200, and the cationic polymer film and After forming an anionic polymer film in which electrostatic attraction acts on the cationic polymer film, a coating layer 400 including photocatalytic nanoparticles having positive charges is formed on the anionic polymer film.

Meanwhile, the cationic polymer membrane may include a polymer material having a repetitive cycle of an electrolyte which is dissolved in water and may have a positive charge. For example, poly allylamine hydrochloride (PAH), polydiaryldimethylammonium chloride (poly (diallyldimethylammonium chloride), PDDA), polyethyleneimine (poly (ethylenimine), PEI) may include at least one from the group consisting of.

On the other hand, the anionic polymer membrane may include a polymer material having a repeating cycle of an electrolyte that is dissolved in water and may have a negative charge, for example, poly (sodium styrenesulfonate) (PSS), polymethacrylic acid ((poly (methacrylic acid), PMAA), polyacrylic acid (poly (acrylic acid), PAA) It may include at least one.

Next, the coating layer 400 is formed on the ionic polymer layer 300, and serves to reduce fouling by photolyzing contaminants.

The coating layer 400 may include photocatalytic nanoparticles, and for example, titanium dioxide, silver, zinc oxide, or the like may be used as the photocatalytic nanoparticles, and among these, titanium dioxide having excellent photocatalytic function is particularly preferable.

On the other hand, the thickness of the coating layer 400 is preferably 1 to 10nm. This is because if less than 1nm titanium dioxide is not evenly coated in a single layer can not effectively play a role of photolysis and hydrophilization as a photocatalyst, if the thickness exceeds 10nm it may have a negative effect on the membrane performance. In addition, more specifically, the thickness of the coating layer 400 is more preferably 2 to 8nm, most preferably 4 to 5nm. This is because when the coating layer is formed within the thickness range, titanium dioxide is widely and uniformly coated on the ionic polymer layer to effectively perform a photolysis role as a photocatalyst.

Since the reverse osmosis membrane according to the present invention has excellent fouling resistance, it can reduce fouling, and can be very useful for desalination of seawater and brine, ultrapure water for semiconductor industry, and various industrial wastewater treatment.

In another aspect, the reverse osmosis membrane manufacturing method according to an embodiment of the present invention, (a) preparing a microporous support; (b) forming an activation layer; (c) forming an ionic polymer layer; And (d) forming a coating layer.

First, (a) preparing a microporous support is a step of preparing a microporous support by casting a polymer material on the nonwoven fabric. Here, as the material of the nonwoven fabric, for example, polyester, polycarbonate, microporous polypropylene, polyphenylene ether, polyvinylidene fluoride and the like can be used, of which polyester is particularly preferred, and as the polymer material, For example, polysulfone, polyethersulfone, polycarbonate, polyethylene oxide, polyimide, polyetherimide, polyetheretherketone, polypropylene, polymethylpentene, polymethylchloride and polyvinylidene fluoride may be used. In particular, polysulfone is preferred.

Next, (b) forming the activation layer is a step of forming an activation layer on the microporous support, specifically, by immersing the microporous support in an amine aqueous solution and then removing the excess aqueous solution on the support and drying the Forming an activation layer on the microporous support. The activation layer is, for example, polyamide, substituted polyamide, polypiperazine, substituted polypiperazine, polyphenylene diamine, substituted polyphenylene diamine, polychloro phenylene diamine, substituted polychloro phenylene Diamine, polybenzidine, substituted polybenzidine, and the like, with polyamide being particularly preferred.

Next, (c) forming the ionic polymer layer refers to forming an ionic polymer layer on the activation layer, wherein the ionic polymer layer formed on the activation layer has a salt excretion rate due to salt ions and electrostatic repulsion. It also serves to improve the function, and also to enable the photocatalytic nanoparticles of the coating layer formed on the ionic polymer layer to be widely and uniformly distributed.

The step (c) of forming an ionic polymer layer may include: (c-1) immersing the active layer in an aqueous polymer electrolyte solution having a cation; (c-2) first washing the surface of the activation layer; (c-3) immersing the active layer in an aqueous polymer electrolyte solution having anions; (c-4) second washing the surface of the activation layer.

In the step (c-1), the activation layer is immersed in an aqueous polymer electrolyte solution having a cation at a concentration of 0.001 M to 1 M, more preferably 0.005 M to 0.1 M, most preferably 0.1 M. This is because when the concentration of the aqueous polymer electrolyte solution having a cation is less than 0.001M, the coating may be performed over the entire active layer, and when the concentration of the aqueous solution of the polymer electrolyte having a cation exceeds 1M, the membrane performance may be adversely affected.

In addition, the polymer having a cation may include a polymer material having a repetitive cycle of an electrolyte which is dissolved in water and may have a positive charge. For example, poly allylamine hydrochloride (PAH), polydiaryldimethyl Ammonium chloride (poly (diallyldimethylammonium chloride), PDDA), polyimide (poly (ethylenimine), PEI) may include at least one from the group consisting of.

Next, in the step (c-2), the activated layer combined with the cationic polymer is put in distilled water and washed first to remove the weakly bound cationic polymer.

Next, in the step (c-3), the activation layer is immersed in an aqueous polymer electrolyte solution having an anion of 0.001 M to 1 M concentration, more preferably 0.005 M to 0.1 M, most preferably 0.1 M concentration. . If the concentration of the aqueous polymer electrolyte solution having an anion is less than 0.001M, the entire active layer can be coated, and if the concentration of the aqueous solution of the polymer electrolyte having an anion is more than 0.1M, the performance of the separation membrane may be adversely affected.

In addition, the polymer having an anion may include a polymer material having a repetitive cycle of an electrolyte which is dissolved in water and may have a negative charge. For example, poly (sodium styrenesulfonate) (PSS), poly It may include at least one from the group consisting of methacrylic acid ((poly (methacrylic acid), PMAA), polyacrylic acid (poly (acrylic acid), PAA).

Next, in the step (c-4), the activated layer combined with the anion polymer is placed in distilled water and washed twice to remove the weakly bound anion polymer.

On the other hand, the step of forming the ionic polymer layer (c) may further include anion treatment of the surface of the activation layer before the step (c-1) when the activation layer is not negatively charged.

Next, in the (d) coating layer forming step, to form a coating layer containing a photocatalytic nanoparticles on the ionic polymer layer. This is because the photocatalytic nanoparticles are coated on the membrane surface to prevent photolysis of the contaminants and adsorption on the membrane surface.

On the other hand, the (d) coating layer forming step, specifically, the ionic polymer layer is immersed in an aqueous solution of photocatalytic nanoparticles having a positive charge for 20 to 30 minutes, and then the surface of the membrane is washed with distilled water to remove excess nanoparticles do. Here, the photocatalytic nanoparticles are not particularly limited as long as they perform a photocatalytic function. For example, titanium dioxide, zinc oxide, silver, and the like may be used, and among them, titanium dioxide having excellent photocatalytic function is preferable.

Hereinafter, the present invention will be described in more detail with reference to specific examples.

Example 1

Put 18 wt% polysulfone solid in DMF (N, N-Dimethylformamide) solution, melt it for more than 12 hours at 80 ~ 85 ℃, and then get uniform liquid. 50㎛ on 150μm thick nonwoven fabric of polyester A thick polysulfone was cast to prepare a porous polysulfone support. The porous polysulfone support thus prepared was immersed in an aqueous solution containing 2% by weight of MPD (m-Phenylenediamine) for 2 minutes, and then the excess aqueous solution on the support was removed using a roller and dried at room temperature for 1 minute, after which the coated The support was immersed in a solution containing 0.1% by weight of TMC (1,3,5-benzenetricarbonyl trichloride) in Isol C solvent (manufactured by SKC Co., Ltd.) for 1 minute and then dried in an oven at 60 ° C for 10 minutes to remove excess organic solution. Then, after washing with 0.2% by weight aqueous sodium carbonate solution at room temperature for 2 hours or more, and washed with distilled water to prepare a polyamide membrane of 200㎛ thickness.

Thereafter, the polyamide membrane was immersed in a poly allylamine hydrochloride (PAH) solution of 0.01 M concentration and poly (sodium styrenesulfonate, PSS) solution of 0.01 M concentration for 5 minutes, respectively, and then distilled water. It was washed with to form an ionic polymer layer consisting of a cationic polymer membrane and an anionic polymer membrane on the surface of the polyamide membrane. Thereafter, the polyamide membrane was immersed in a 0.05 wt% titanium dioxide aqueous solution having a positive charge to form a coating layer containing titanium dioxide on the surface of the membrane to prepare a reverse osmosis membrane having excellent fouling resistance.

Example 2

A reverse osmosis membrane was prepared in the same manner as in Example 1 except that 0.1 wt% of titanium dioxide was used instead of 0.05 wt% of titanium dioxide.

Example 3

A reverse osmosis membrane was prepared in the same manner as in Example 1 except that 0.15 wt% of titanium dioxide was used instead of 0.05 wt% of titanium dioxide.

Example 4

A reverse osmosis membrane was prepared in the same manner as in Example 1 except that 0.2 wt% titanium dioxide aqueous solution was used instead of 0.05 wt% titanium dioxide aqueous solution.

Example 5

A reverse osmosis membrane was prepared in the same manner as in Example 1 except that 0.25 wt% titanium dioxide aqueous solution was used instead of 0.05 wt% titanium dioxide aqueous solution.

Example 6

A reverse osmosis membrane was prepared in the same manner as in Example 1 except that 0.3 wt% of titanium dioxide was used instead of 0.05 wt% of titanium dioxide.

Comparative Example 1

Coating layer containing titanium dioxide on the surface of the film by immersing the polyamide film in 0.05% by weight aqueous titanium dioxide solution having a positive charge, without forming an ionic polymer layer on the surface of the polyamide film prepared in the same manner as in Example 1 To form a reverse osmosis membrane.

Comparative Example 2

None of the ionic polymer layer and the coating layer were formed on the surface of the polyamide membrane prepared in the same manner as in Example 1.

Experimental Example 1

The initial salt removal rate and initial permeation flow rate of the reverse osmosis membranes prepared in Examples 1 to 6 and Comparative Examples 1 and 2 were measured. The initial salt removal rate and the initial permeate flow rate were obtained by mounting the reverse osmosis membrane prepared by Examples 1 to 6 and Comparative Examples 1 and 2 to the reverse osmosis membrane cell apparatus including a flat plate permeation cell, a high pressure pump, a reservoir, and a cooling device. Then, it measured while permeating a 32,000 ppm sodium chloride aqueous solution at 25 degreeC by the flow volume of 1400 mL / min. The planar type transmissive cell is a cross-flow type, and the effective permeable area is 140 cm ² . The reverse osmosis membrane was installed in the permeation cell, and then preliminarily operated for about 1 hour using tertiary distilled water to stabilize the evaluation equipment. Then, 32,000 ppm of sodium chloride solution was added thereto, and the permeate flow rate was calculated by measuring the amount of water permeated for 10 minutes at 800 psi pressure after operating for 1 hour until the pressure and permeate flow rate reached a steady state. The salt rejection rate was calculated by analyzing the salt concentration before and after permeation. The measurement results are shown in Table 1 below.

The initial flux (gallon / ft ² · day) Initial salt exclusion rate (%) Example 1 17.88 96.64 Example 2 17.46 97.08 Example 3 17.59 97.76 Example 4 17.45 98.80 Example 5 16.72 98.36 Example 6 17.19 98.37 Comparative Example 1 17.91 96.98 Comparative Example 2 18.30 96.20

Experimental Example 2

After measuring the initial salt excretion rate and permeate flow rate by Experimental Example 1, 100 ppm casein solution in which casein was dissolved in an aqueous solution of pH 11 or higher was charged into a tank. The change in salt excretion rate and flow rate 2 hours after the casein aqueous solution was added was measured. The method of measuring the salt excretion rate and flow rate is the same as in Experimental Example 1. The measurement results are shown in the following [Table 2].

After 2 hours the flux of casein transmission (gallon / ft ² · day) % Salt rejection after 2 hours of casein permeation Example 1 17.51 96.11 Example 2 17.38 96.25 Example 3 17.64 96.97 Example 4 17.48 98.43 Example 5 16.21 98.61 Example 6 17.54 98.79 Comparative Example 1 14.98 95.02 Comparative Example 2 15.08 94.97

Referring to Tables 1 and 2, Examples 1 to 6 maintained the initial permeate flow rate and the permeate flow rate after 2 hours of casein addition, and the initial salt excretion rate and the salt excretion rate after 2 hours of casein addition were also maintained almost the same. On the other hand, Comparative Examples 1 and 2 can be seen that the permeate flow rate is significantly lower than the initial permeate flow rate 2 hours after the casein input, the salt excretion rate is also significantly lower than the initial salt excretion rate 2 hours after the casein input. That is, unlike Comparative Examples 1 and 2, Examples 1 to 6 are significantly superior in fouling resistance to Comparative Examples 1 and 2 from the result that the permeation flow rate and salt rejection rate before and after the injection of casein as a pollutant are kept constant. It can be seen.

100 microporous support
200 active layers
300 Ionic Polymer Layer
400 coating layer

Claims (20)

Microporous support;
An activation layer formed on the microporous support;
An ionic polymer layer formed on the activation layer; And
The reverse osmosis membrane formed on the ionic polymer layer, and excellent in fouling resistance including a coating layer comprising photocatalytic nanoparticles.
The method of claim 1,
The microporous support is selected from the group consisting of polysulfone, polyethersulfone, polycarbonate, polyethylene oxide, polyimide, polyetherimide, polyetheretherketone, polypropylene, polymethylpentene, polymethylchloride and polyvinylidene fluoride Reverse osmosis membranes having excellent stain resistance, including those selected.
The method of claim 1,
The active layer is polyamide, substituted polyamide, polypiperazine, substituted polypiperazine, polyphenylene diamine, substituted polyphenylene diamine, polychloro phenylene diamine, substituted polychloro phenylene diamine, polybenzidine The reverse osmosis membrane excellent in fouling resistance, comprising at least one selected from the group consisting of a substituted polybenzidine.
The reverse osmosis membrane of claim 1, wherein the ionic polymer layer has a structure in which a cationic polymer membrane and an anionic polymer membrane are sequentially stacked.
The method of claim 4, wherein the cationic polymer membrane is made of poly allylamine hydrochloride (PAH), polydiaryldimethylammonium chloride (poly (diallyldimethylammonium chloride), PDDA), polyethyleneimine (poly (ethylenimine), PEI) Reverse osmosis membrane excellent pollution resistance comprising at least one species from the group.
The method of claim 4, wherein the anionic polymer film is poly (sodium styrenesulfonate), polymethacrylic acid (poly (methacrylic acid), PMAA), poly (acrylic acid), PAA The reverse osmosis membrane excellent pollution resistance that comprises at least one from the group consisting of).
The reverse osmosis membrane of claim 1, wherein the photocatalytic nanoparticles of the coating layer comprise at least one selected from the group consisting of titanium dioxide, silver, and zinc oxide.
The reverse osmosis membrane of claim 1, wherein the ionic polymer layer has a thickness of 1 nm to 10 nm.
The reverse osmosis membrane of claim 8, wherein the ionic polymer layer has a thickness of 2 nm to 8 nm.
The reverse osmosis membrane of claim 9, wherein the ionic polymer layer has a thickness of 3 nm to 6 nm.
The reverse osmosis membrane of claim 1, wherein the coating layer has a thickness of 1 nm to 10 nm.
The reverse osmosis membrane of claim 11, wherein the coating layer has a thickness of 2 nm to 8 nm.
The reverse osmosis membrane of claim 12, wherein the coating layer has a thickness of 4 nm to 5 nm.
(a) preparing a microporous support;
(b) forming an activation layer on the microporous support;
(c) forming an ionic polymer layer on the activation layer; And
(d) a method for producing a reverse osmosis membrane having excellent fouling resistance, comprising forming a coating layer including photocatalytic nanoparticles on the ionic polymer layer.
15. The method of claim 14,
The microporous support is selected from the group consisting of polysulfone, polyethersulfone, polycarbonate, polyethylene oxide, polyimide, polyetherimide, polyetheretherketone, polypropylene, polymethylpentene, polymethylchloride and polyvinylidene fluoride Reverse osmosis membrane production method comprising the selected.
15. The method of claim 14,
The active layer is a reverse osmosis membrane manufacturing method excellent pollution resistance that comprises a polyamide membrane.
15. The method of claim 14,
The step (c)
(c-1) immersing the active layer in an aqueous polymer electrolyte solution having a cation;
(c-2) first washing the surface of the activation layer;
(c-3) immersing the active layer in an aqueous polymer electrolyte solution having anions;
(C-4) excellent reverse osmosis membrane production method comprising the step of second washing the surface of the active layer.
18. The method of claim 17,
The reverse osmosis membrane manufacturing method excellent pollution resistance further comprising the step of anion treating the surface of the active layer before the step (c-1).
The method according to claim 17, wherein in the step (c-1), the concentration of the polymer electrolyte solution containing the cation is 0.001M to 0.1M.
18. The method of claim 17, wherein in the step (c-1), the concentration of the aqueous polymer electrolyte solution having the anion is 0.001M to 0.1M.

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