KR101659122B1 - Polyamide water-treatment membranes having properies of high salt rejection and high flux and manufacturing method thereof - Google Patents

Abstract

The present invention relates to a water treatment separator comprising a porous support and a polyamide active layer formed on the porous support, wherein a hydrophilic group is introduced into the polyamide active layer, and a method for producing the same.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a polyamide-based water treatment membrane having excellent salt removal rate and permeation flow rate characteristics,

More particularly, the present invention relates to a polyamide-based water treatment separator having a hydrophilic group in a polyamide active layer to improve a salt removal ratio and a permeate flow rate characteristic, and a method for producing the same .

Due to the serious pollution and water shortage in recent years, it is urgent to develop new water resources. Studies on the pollution of water quality are aiming at the treatment of high quality living and industrial water, various domestic sewage and industrial wastewater, and interest in the water treatment process using the separation membrane having the advantage of energy saving is increasing. In addition, the accelerated enforcement of environmental regulations is expected to accelerate the activation of membrane technology. Conventional water treatment process is difficult to meet the regulations that are strengthened, but membrane technology is expected to become a leading technology in the water treatment field because it guarantees excellent treatment efficiency and stable treatment.

Liquid separation is classified into micro filtration, ultrafiltration, nano filtration, reverse osmosis, sedimentation, copper transport and electrodialysis depending on the pores of the membrane.

In recent years, the use of inorganic separators has been expanding in view of their excellent properties such as heat resistance and durability. However, most commercialized separators have been applied to organic separators Is a polymer separator.

Conventionally, asymmetric cellulose acetate has been widely used as an organic separation membrane. Cellulose-based polymers have a linear backbone structure and are highly crystalline, are not well soluble in water, and are excellent in hydrophilicity. Therefore, they are used as materials for microfiltration membranes or ultrafiltration membranes. However, the cellulose-based polymer has poor physical properties such as chemical resistance, heat resistance, and stain resistance, and is therefore difficult to use as a reverse osmosis membrane material. In addition, due to various drawbacks such as narrow operating pH range, deformation at high temperature, high cost for operation, and vulnerability to microorganisms, to be.

A polyamide-based polymer membrane has emerged to overcome the disadvantages of the above-mentioned cellulosic polymers. That is, the TFC membrane (Thin Film Composite membrane) comprising a polyamide-based thin film as an active layer has a higher stability against pH change than a conventional cellulose-based asymmetric membrane and can be operated at a lower pressure, And is the main species of the water treatment separator at present.

Specifically, the polyamide-based separation membrane is formed by forming a polysulfone layer on a nonwoven fabric to form a microporous support, and immersing the microporous support in an aqueous solution of m-Phenylene Diamine (mPD) to form an mPD layer , And then immersing or coating the same in an organic solvent of triMesoyl Chloride (TMC) to form a polyamide active layer by interfacial polymerization with the mPD layer in contact with TMC. According to such a manufacturing method, since the nonpolar solution and the polar solution are in contact with each other, polymerization occurs only at the interface thereof, and a polyamide active layer having a very thin thickness is formed.

On the other hand, such a reverse osmosis membrane is commercially used and desorbs salt in a large amount in order to desalt salt, and the permeate flow characteristics capable of passing excess water even at a relatively low pressure should be excellent. Therefore, it is required to develop a technology for further improving the salt removal rate and permeate flow characteristics of the reverse osmosis membrane.

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and it is an object of the present invention to provide a polyamide-based water treatment separator having a salt removal rate and a permeation flow rate by introducing a hydrophilic group into the polyamide active layer.

In one aspect, the present invention provides a water treatment separator comprising a porous support and a polyamide active layer formed on the porous support, wherein a hydrophilic group is introduced into the polyamide active layer.

At this time, the polyamide active layer is formed by interfacial polymerization of an amine compound and an acyl halide compound, and the amine compound includes an amine compound having a hydrophilic group.

At this time, it is preferable that the hydrophilic group is a sulfonic acid group, a sulfonic acid group, a carboxyl group, a carboxylic acid group, a phosphonic acid group, a phosphonic acid group, a hydroxyl group or a thiol group.

The amine compound having a hydrophilic group may be composed of at least one benzene ring, and the benzene ring may have a structure having two or more amines and at least one hydrophilic group, specifically, a structure represented by the following formula (1) .

Preferably, the amine compound having a hydrophilic group is selected from the group consisting of 2,2-benzidine disulfonic acid, 2,5-diaminobenzene-1,4-disulfonic acid and 2,5-diaminobenzenesulfonic acid And may be any one or more selected.

The amine compound may be a combination of a polyfunctional amine compound and an amine compound having a hydrophilic group. In this case, the polyfunctional amine compound may be at least one selected from the group consisting of m-phenylenediamine, p-phenylenediamine, Chloro-1,3-phenylenediamine, 6-chloro-1,3-phenylenediamine, 3-chloro-1,4-phenylenediamine or a mixture thereof, and the polyfunctional amine The weight ratio of the compound and the amine compound having a hydrophilic group may be 99.9: 0.1 to 90: 10.

On the other hand, in the water treatment separation membrane of the present invention, the repeating unit of the amine compound having the hydrophilic group as a whole may be contained in an amount of 0.04 to 4% in the entire polyamide active layer.

The water treatment separation membrane may have an initial salt removal rate of 99% or more and an initial permeation flow rate of 37 to 45 gallon / ft ² · day or more when passing a sodium chloride (NaCl) solution having a concentration of 32,000 ppm at 800 psi pressure, The amount of change in the permeated flow rate after cleaning may be less than or equal to 6%.

Meanwhile, in the water treatment separation membrane of the present invention, the porous support may be a microfiltration membrane, an ultrafiltration membrane, a nanofiltration membrane, or a reverse osmosis membrane.

In another aspect, the present invention provides a water treatment apparatus including at least one water treatment module including at least one water treatment separation membrane and at least one water treatment module.

In another aspect, the present invention provides a method of forming a porous support, comprising: forming an aqueous solution layer comprising an amine compound having a hydrophilic group on a porous support; And contacting the aqueous solution layer with an organic solution containing an acyl halide to form a polyamide layer.

On the other hand, the amine compound having the hydrophilic group may be contained in an amount of 0.006 to 0.6% by weight in the entire aqueous solution containing the amine compound.

The water treatment separation membrane of the present invention has the effect of introducing a hydrophilic group into the inside of the polyamide active layer to form pores having hydrophilic properties, and having excellent salt removal rate and permeation flow rate.

In addition, according to the method for preparing a water treatment separation membrane of the present invention, a water treatment separation membrane having an excellent salt removal ratio and a permeation flow rate can be manufactured through a process of adding an amine compound having a hydrophilic group to an aqueous amine compound solution without a separate post treatment.

Hereinafter, preferred embodiments of the present invention will be described. However, the embodiments of the present invention can be modified into various other forms, and the scope of the present invention is not limited to the embodiments described below. Further, the embodiments of the present invention are provided to more fully explain the present invention to those skilled in the art.

The present inventors have found that, in the case of a water treatment separation membrane produced by a general method, water molecules have a high removal rate and a somewhat lower permeation flow rate as the water molecules move through the pores at the level of a few omstrong in the synthesized polyamide . Accordingly, the present inventors have conducted intensive studies to produce a water treatment separation membrane having a high salt removal rate and a good permeation flow rate, and as a result, it has become possible to introduce a hydrophilic group into the synthesized polyamide polymer separation membrane, The present invention has been completed.

Accordingly, the present invention is characterized by (1) a porous support, and (2) a polyamide active layer formed on the porous support, wherein a hydrophilic group is introduced into the polyamide active layer.

The porous support may be a porous support having a coating layer of a polymeric material formed on a nonwoven fabric. Examples of the polymeric material include polysulfone, polyethersulfone, polycarbonate, polyethylene oxide, polyimide, poly An ether imide, a polyether ketone, a polypropylene, a polymethylpentene, a polymethylchloride, and a polyvinylidene fluoride, but the present invention is not limited thereto. Of these, polysulfone is particularly preferable.

On the other hand, the polyamide active layer (2) formed on the porous support may be formed by interfacial polymerization of an amine compound and an acyl halide compound. At this time, the amine compound is generally a polyfunctional amine compound and a mixture thereof. In the present invention, an amine compound having a hydrophilic group is used as described below. Also, the acyl halide compound is an aromatic compound having 2 to 3 carboxylic acid halides, including, but not limited to, trimethoyl chloride, isophthaloyl chloride, terephthaloyl chloride, or a mixture thereof .

Next, a hydrophilic group is introduced into the inside of the polyamide active layer.

More specifically, the polyamide active layer is formed by interfacial polymerization of an amine compound and an acyl halide compound, and the amine compound includes an amine compound having a hydrophilic group.

In this case, the hydrophilic group is for enhancing the hydrophilicity of the active layer of the water treatment separation membrane, and is not limited thereto, but is preferably a sulfonic acid group, a sulfonic acid group, a carboxyl group, a carboxylic acid group, a phosphonic acid group, a phosphonic acid group, a hydroxyl group or a thiol group desirable.

In the case where a hydrophilic group is directly introduced into the polyamide active layer, since the hydrophilic functional group is chemically bonded directly on the pore structure at the level of a few omstrong generated after the polyamide polymerization, only pure water from which other substances are removed is permeated It is possible to obtain an effect of modifying the path of water movement more hydrophilically under the water purification process. As a result, the permeation flux per unit time can be increased, and a highly permeable membrane can be produced.

As described above, when the polyamide active layer is formed, interfacial polymerization reaction occurs between the amine compound in the aqueous solution previously applied and the acyl halide which is in contact with the amine compound in the subsequent step. Therefore, when an aqueous solution layer containing an amine compound having a hydrophilic group is formed on the porous support as in the present invention, a hydrophilic group is introduced into the polyamide membrane while the amine compound reacts with the acyl halide.

That is, according to the method of the present invention, a hydrophilic group is directly introduced into the polyamide which constitutes the polyamide active layer, unlike the conventional method in which a coating layer containing a hydrophilic compound is applied on the polyamide active layer, And the like. In this case, unlike the case of simply treating the surface of the separation membrane with a hydrophilic material, since the hydrophilic material acts directly on the movement path of the water, the effect of increasing the permeation flow rate is great and the effect is continuously maintained after the formation of the membrane .

At this time, the amine compound having a hydrophilic group usable in the present invention is not limited thereto, but it is preferably composed of at least one benzene ring, and the benzene ring preferably has two or more amines and at least one hydrophilic group.

Further, preferably, the amine compound of the present invention may be a compound represented by the following formula (1) or (2).

[Chemical Formula 1]

Wherein i is an integer of 1 to 4, preferably an integer of 1 to 2, and R ₁ is a sulfonic acid group, a sulfonic acid group, a carboxyl group, a carboxylic acid group, a phosphonic acid group, a phosphonic acid group, a hydroxyl group or a thiol group Preferably, it is a sulfonic acid group or a sulfonic acid base.

(2)

Wherein n is an integer of 0 to 3, preferably 0 or 1, j, k and 1 are each independently an integer of 0 to 3, R ₂ and R ₄ are each independently a sulfonic acid group, a base, a carboxyl group, a carboxylic acid base, a phosphonic acid group, phosphonic acid base, a hydroxyl group or thiol group, R ₃ is a sulfonic acid group, a sulfonic acid base, a carboxyl group, a carboxylic acid base, a phosphonic acid group, phosphonic acid base, a hydroxyl group, thiol group, Amino group or hydrogen. More preferably, each of R ₂ to R ₄ may independently be a sulfonic acid group or a sulfonic acid group.

Specific examples of the amine compound having a hydrophilic group include, but are not limited to, 2,2-benzidine disulfonic acid, 2,5-diaminobenzene-1,4-disulfonic acid and 2,5- Phobic acid, and the like.

In the present invention, as the amine compound, a combination of a polyfunctional amine compound and an amine compound having a hydrophilic group may be used.

The polyfunctional amine compound may be an amine compound capable of interfacial polymerization with an acyl halide to form a conventional polyamide active layer. For example, aromatic polyfunctional amine compounds such as cyclohexane diamine, piperazine and piperazine derivatives, Amine; N, N-dimethyl-1,3-phenylenediamine, xylylenediamine, benzidine, benzidine derivatives or mixtures thereof. Of these, aromatic polyfunctional amines are preferred, and m-phenylenediamine, p-phenylenediamine, 1,3,6-benzenetriamine, 4-chloro-1,3- 1,3-phenylenediamine, 3-chloro-1,4-phenylenediamine or a mixture thereof.

In this case, the weight ratio of the polyfunctional amine compound and the amine compound having a hydrophilic group may be 99.9: 0.1 to 90: 10, preferably 99.6: 0.4 to 95: 5. At this time, if the content ratio is less than 99.9: 01, the effect of increasing the flow rate due to hydrophilicity is insignificant. If the content ratio is more than 90:10, the decrease of the salt removal rate becomes severe and the effect of increasing the flow rate is not confirmed any more.

On the other hand, in the case of the water treatment separation membrane of the present invention, the repeating unit of the amine compound having the hydrophilic group is included in the total polyamide active layer in an amount of 0.04 to 4%, preferably 0.16 to 2%. When the above range is satisfied, the salt removal rate is maintained at a level (> 95%) that can be used in a conventional reverse osmosis membrane, and at the same time, the permeation flow rate is increased by 50%.

According to the experiment of the present inventors, in the case of the separation membrane of the present invention in which the polyamide active layer having a hydrophilic group was formed as described above, the initial salt removal rate was 99% or more and the initial flow rate was 37 gallon / ft ² · day or more and has an initial salt removal rate of 99% or more and an initial flow rate of 25 gallon / ft ² · day or more as measured at a pressure of 250 ppm in a 2000 ppm NaCl aqueous solution, and has a salt removal rate equivalent to that of conventional reverse osmosis membranes, .

In addition, the water treatment separator has an initial salt removal rate of more than 99%, an initial flow rate of 36.5 gallons / ft ² · day or more, measured at a pressure of 800 psi, a NaCl aqueous solution of 32000 ppm after washing, The initial salt removal rate was 99% or more and the initial flow rate was 24.5 gallons / ft ² · day or more.

That is, the water treatment separation membrane according to the present invention maintains the excellent permeation flow rate performance even when the change in the permeation flow rate measured under the high pressure condition and the low pressure condition after washing is 6% or less. This shows that, unlike the conventional water-treating membrane coated with a hydrophilic membrane, the direct polyamide active layer has a hydrophilic-grouped pore, showing a change in permeation flow rate of 9% or more after washing, and has a remarkable effect of continuously having a high permeate flow rate .

Meanwhile, the water treatment separation membrane including the above components may be used for a micro filtration, an ultrafiltration, a nano filtration or a reverse osmosis membrane, and preferably a reverse osmosis membrane have.

The present invention also relates to a water treatment module including the water treatment separation membrane according to the present invention and a water treatment apparatus including the water treatment module.

The water treatment module to which the water treatment separation membrane of the present invention is applied is excellent in salt removal rate and permeation flow rate and is excellent in chemical stability and can be used as a microfiltration membrane, an ultrafiltration membrane, a nanofiltration membrane, and a membrane filter for domestic / industrial water purification, sewage treatment, Or as a reverse osmosis membrane module.

The concrete type of the water treatment module that can be constructed using the water treatment separation membrane of the present invention is not particularly limited, and examples thereof include a plate & frame module, a tubular module, a hollow & Spiral wound modules, and the like. Further, as long as the water treatment module of the present invention includes the above-described water treatment separation membrane of the present invention, other structures and manufacturing methods are not particularly limited and general means known in this field can be employed without limitation.

Next, a method for producing the water treatment separation membrane of the present invention will be described.

More specifically, the water treatment separation membrane of the present invention comprises a step of forming an aqueous solution layer containing an amine compound having a hydrophilic group on a porous support and an organic solution containing an acyl halide on the aqueous solution layer to form a polyamide active layer The method comprising the steps of:

At this time, in the step of forming the aqueous solution layer containing the amine compound having the hydrophilic group, the hydrophilic group is for improving the hydrophilicity of the active layer of the water treatment separation membrane. However, the hydrophilic group may be a sulfonic acid group, a sulfonic acid group, a carboxyl group, A phosphonic acid group, a phosphonic acid group, a hydroxyl group or a thiol group.

Examples of the amine compound having a hydrophilic group include, but are not limited to, 2,2-benzidine disulfonic acid, 2,2-benzidine disulfonic acid, 2,5-diaminobenzene-1,4-disulfonic acid and 2 , 5-diaminobenzenesulfonic acid, and the like.

The amine compound having a hydrophilic group may be contained in an amount of about 0.006 to 0.6% by weight, preferably about 0.024 to 0.48% by weight, more preferably 0.048 to 0.24% by weight in the whole aqueous solution. When the content of the amine compound having a hydrophilic group satisfies the above range, the polyamide active layer can be smoothly formed while the effect of improving the permeation flow rate is excellent.

On the other hand, the aqueous solution layer may be a combination of a polyfunctional amine compound and an amine compound having a hydrophilic group. As the polyfunctional amine compound, amine compounds used in the preparation of a water treatment separation membrane may be used without limitation, for example, aromatic polyfunctional amines such as cyclohexane diamine, piperazine and piperazine derivatives; N, N-dimethyl-1,3-phenylenediamine, xylylenediamine, benzidine, benzidine derivatives or mixtures thereof. Of these, aromatic polyfunctional amines are preferred, and m-phenylenediamine, p-phenylenediamine, 1,3,6-benzenetriamine, 4-chloro-1,3- 1,3-phenylenediamine, 3-chloro-1,4-phenylenediamine or a mixture thereof.

The amine compound having the hydrophilic group may be contained in an amount of 0.1 to 10 parts by weight, preferably 0.4 to 5 parts by weight, based on 100 parts by weight of the solid content of the polyfunctional amine compound.

Meanwhile, the solvent of the amine aqueous solution is preferably a polar solvent such as water, and the amine aqueous solution may further contain an additive agent such as triethylamine and camphorsulfonic acid, if necessary.

Further, the method of forming the amine aqueous solution layer on the porous support does not exclude any method as long as it is capable of forming an aqueous solution on the support. For example, any method such as spraying, coating, immersion, dropping, etc. can be used.

After the formation of the aqueous solution layer, a step of selectively removing an aqueous solution containing an excess of the amine compound may be further carried out. When the excess aqueous solution is thus removed, the interfacial polymerization layer can be safely formed on the support and a uniform layer can be formed. The removal of the excess aqueous solution can be performed using a sponge, an air knife, a nitrogen gas blowing, a natural drying, a compression roll or the like, but is not limited thereto.

Next, in the step of forming the polyamide active layer by contacting the organic solution containing the acyl halide compound on the aqueous solution layer, the amine compound coated on the surface reacts with the acyl halide compound to form polyamide by interfacial polymerization, And adsorbed on the microporous support to form a thin film. In the contact method, a polyamide active layer may be formed by a method such as dipping, spraying, or coating.

The acyl halide compound is an aromatic compound having 2 to 3 carboxylic acid halides, including, but not limited to, trimethoyl chloride, isophthaloyl chloride, terephthaloyl chloride, or a mixture thereof Do.

On the other hand, as the organic solvent of the solution containing the acyl halide compound, it is preferable to use a solvent that does not participate in the interfacial polymerization reaction, does not cause chemical bonding with the acyl halide compound, and does not damage the porous support layer. Examples of the organic solvent include aliphatic hydrocarbon solvents such as Freons and hydrophobic liquids such as hexane, cyclohexane, heptane, and alkane having 5 to 12 carbon atoms that are immiscible with water, for example, alkanes having 5 to 12 carbon atoms And mixtures thereof such as Isol-C (Exxon Cor.) And Isol-G (Exxon Cor.).

The contact time is preferably about 1 minute to 5 hours, more preferably about 1 minute to 3 hours. When the contact time is less than 1 minute, the coating layer is not sufficiently formed, and when the contact time exceeds 5 hours, there is a negative influence that the thickness of the coating layer becomes too thick to reduce the permeation flow rate of the water treatment separator.

Meanwhile, when the polyamide active layer is formed on the porous support by the above-described method, the polyamide active layer may be selectively dried and washed. At this time, the drying is preferably performed in an oven at 45 ° C to 80 ° C for about 1 minute to 10 minutes. The washing is not particularly limited, but can be performed, for example, in a basic aqueous solution. The basic aqueous solution which can be used is not particularly limited, but for example, an aqueous solution of sodium carbonate can be used. Specifically, the basic aqueous solution is preferably performed in an aqueous solution of sodium carbonate at 20 ° C to 30 ° C for 1 hour to 24 hours.

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

≪ Example 1 >

18% by weight of polysulfone solids were added to DMF (N, N-dimethylformamide) solution and melted at 80 ° C to 85 ° C for 12 hours or more to obtain a uniform liquid phase. This solution is cast on a nonwoven fabric having a thickness of 95 to 100 mu m made of polyester to a thickness of 45 to 50 mu m. The cast nonwoven fabric was then immersed in water to prepare a porous polysulfone support.

The porous polysulfone support prepared by the above method was mixed with 7.92 wt% of metaphenylenediamine, 0.08 wt% of BDSA (2,2-benzidine disulfonic acid), 1 wt% of triethylamine and 2.3 wt% of camphorsulfonic acid , The excess aqueous solution on the support was removed using a 25 psi roller and dried at room temperature for 1 minute.

Then, an organic solution containing 0.2% by volume of trimesoyl chloride (TMC) was applied to the surface of the coated support with an Hexane solvent (Sigma Aldrich) to perform interfacial polymerization, and excess organic solution was removed Lt; RTI ID = 0.0 > 60 C < / RTI >

The water treatment separation membrane obtained by the above method was immersed in a 0.2 wt% sodium carbonate aqueous solution for 2 hours or more and then washed with distilled water for 1 minute to prepare a water treatment membrane having a polyamide active layer.

≪ Example 2 >

Except that 0.16 wt% of BDSA (2,2-benzidine disulfonic acid) was used in place of 0.08 wt% of BDSA (2,2-benzydine disulfonic acid), to prepare a water treatment separation membrane.

≪ Example 3 >

A water treatment separation membrane was prepared in the same manner as in Example 1, except that BDSA (2,2-benzidine disulfonic acid) was used in an amount of 0.24 wt% instead of 0.08 wt% of BDSA (2,2-benzidine disulfonic acid).

<Example 4>

Except that 0.32 wt% of BDSA (2,2-benzidine disulfonic acid) was used in place of 0.08 wt% of BDSA (2,2-benzidine disulfonic acid).

&Lt; Comparative Example 1 &

A water treatment separation membrane was prepared in the same manner as in Example 1, except that 0.08% by weight of an amine compound aqueous solution except for BDSA (2,2-benzydinedisulfonic acid) was used.

&Lt; Comparative Example 2 &

The water treatment separator prepared in Comparative Example 1 was immersed in a solution containing 0.03 wt% of camphorsulfonic acid ((7,7-dimethyl-2-oxobicyclo [2,2,1] heptan-1-yl) methanesulfonic acid) % And sodium carbonate (0.05 wt%) at room temperature for 2 minutes to form a hydrophilic coating film on the polyamide active layer.

Then, the water treatment separation membrane was washed with 0.2 wt% sodium carbonate aqueous solution at room temperature for 30 minutes, and then washed with distilled water to prepare a water treatment separation membrane having the coating membrane.

< Experimental Example  1 - Initial Salt exclusion rate  And initial permeate flow measurement>

The initial salt rejection rate and initial permeate flow rate of the water treatment membranes prepared in Examples 1 to 4 and Comparative Examples 1 and 2 were evaluated by the following methods. The initial salt rejection rate and the initial permeate flux were measured at 25 ° C while the aqueous sodium chloride solution was supplied at a concentration of 32,000 ppm at 800 psi pressure or 2,000 ppm concentration at 250 psi pressure at a flow rate of 4500 mL / min. The water treatment membrane cell device used for the evaluation of the membrane was equipped with a plate type permeable cell, a high pressure pump, a reservoir and a cooling device. The structure of the plate type permeable cell was a cross-flow type with an effective permeable area of 28 cm ² . After the washed water treatment membrane was installed in the permeation cell, the preliminary operation was performed for about 1 hour by using the third distilled water for stabilization of the evaluation equipment. Then, the apparatus was operated for about 1 hour until the pressure and permeate flow rate reached a steady state by replacing with 32,000 ppm sodium chloride aqueous solution. Then, the flow rate was calculated by measuring the amount of water permeated for 10 minutes, and the conductivity was measured with a Conductivity Meter ) Was used to calculate the salt rejection rate by analyzing the salt concentration before and after permeation. The measurement results are shown in [Table 1].

division
32000 ppm / 800 psi 2000 ppm / 250 psi Salt Removal Rate (%) Permeate flow (GFD) Salt Removal Rate (%) Permeate flow (GFD) Example 1 99.42 37.20 99.50 25.29 Example 2 99.32 39.85 99.38 29.72 Example 3 99.39 41.68 99.39 33.36 Example 4 99.30 42.84 99.36 35.77 Comparative Example 1 99.42 36.14 99.47 23.55 Comparative Example 2 99.30 37.43 99.29 25.41

The results of Table 1 show that when the polyamide active layer is formed using an amine compound having a hydrophilic group as in Examples 1 to 4, the membrane has an equivalent salt removal ratio as compared with the separation membrane of Comparative Example 1, % &Lt; / RTI &gt; to &lt; RTI ID = 0.0 &gt; 20%. &Lt; / RTI &gt;

< Experimental Example  2 - After washing  Change in permeation flow rate>

In the water treatment membranes prepared in Examples 1 to 4 and Comparative Examples 1 and 2, the amount of change in the permeated flow rate before and after washing was evaluated by the following method. The membrane surface and equipment were washed for one hour using third distilled water, and the permeate flow rate and salt removal rate were measured under the same conditions as described in Experimental Example 1. Then, the rate of change was measured by comparing the measured value with the initial permeate flow rate and the salt removal rate measured in Experimental Example 1. [ The measurement results are shown in Table 2.

division
After washing
32000 ppm / 800 psi After washing
2000 ppm / 250 psi Rate of change
32000 ppm / 800 psi Rate of change
2000 ppm / 250 psi Salt Removal Rate (%) Permeate flow (GFD) Salt Removal Rate (%) Permeate flow (GFD) Rate of Salt Removal Rate Change Permeate flow rate change rate Rate of Salt Removal Rate Change Permeate flow rate change rate Example 1 99.62 38.83 99.42 24.83 0.20 4.38 0.08 1.81 Example 2 99.44 40.52 99.28 29.31 0.12 1.68 0.10 1.38 Example 3 99.42 41.29 99.53 33.42 0.03 0.94 0.14 0.18 Example 4 99.38 40.44 99.49 33.97 0.08 5.60 0.13 5.03 Comparative Example 1 99.50 35.79 99.42 23.12 0.08 0.97 0.05 1.83 Comparative Example 2 99.38 34.82 99.34 23.08 0.08 6.97 0.05 9.17

It can be seen from the above [Table 2] that the permeation rate change rate before and after cleaning of the water treatment separation membrane of the present invention manufactured by Examples 1 to 4 is less than 6% at both high pressure and low pressure conditions. In contrast, in the case of Comparative Example 2 in which a hydrophilic film was formed on the surface, it was found that the rate of change of the permeated flow rate before and after washing at low pressure was 9% or less and 7% at high pressure. In the case of the water treatment separation membrane of the present invention, it is considered that the hydrophilic membrane exists in the polyamide active layer and is not washed away by washing, whereas in the case of Comparative Example 2, the hydrophilic membrane is washed away during washing.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is to be understood that the invention is not limited to the disclosed exemplary embodiments, but, on the contrary, It will be obvious to those of ordinary skill in the art.

Claims (17)

A porous support; And
And a polyamide active layer formed on the porous support,
A hydrophilic group is introduced into the inside of the polyamide active layer,
The polyamide active layer is formed by interfacial polymerization of an amine compound and an acyl halide compound,
The amine compound is a combination of a polyfunctional amine compound and an amine compound having a hydrophilic group,
The weight ratio of the polyfunctional amine compound to the amine compound having a hydrophilic group is 99.9: 0.1 to 90: 10,
Wherein the amine compound having a hydrophilic group is 2,2-benzidine disulfonic acid.
delete delete delete delete delete delete The method according to claim 1,
The polyfunctional amine compound may be at least one selected from the group consisting of m-phenylenediamine, p-phenylenediamine, 1,3,6-benzenetriamine, 4-chloro-1,3-phenylenediamine, Diamine, 3-chloro-1,4-phenylenediamine or a mixture thereof.
delete delete The method according to claim 1,
Wherein the water treatment separation membrane has an initial salt removal rate of 99% or more and an initial permeation flow rate of 37 to 45 gallon / ft ² · day or more when passing a sodium chloride (NaCl) solution having a concentration of 32,000 ppm at 800 psi pressure.
The method according to claim 1,
Wherein the water treatment separation membrane has a change amount of the permeation flow rate after cleaning of 6% or less.
The water treatment separator according to claim 1, wherein the porous support is a microfiltration membrane, an ultrafiltration membrane, a nanofiltration membrane or a reverse osmosis membrane.
A water treatment module comprising at least one water treatment membrane according to any one of claims 1, 8, 11 to 13.
A water treatment apparatus comprising at least one water treatment module according to claim 14.
Forming an aqueous solution layer comprising an amine compound on the porous support; And
And contacting the aqueous solution layer with an organic solution containing an acyl halide to form a polyamide active layer,
The amine compound is a combination of a polyfunctional amine compound and an amine compound having a hydrophilic group,
The weight ratio of the polyfunctional amine compound to the amine compound having a hydrophilic group is 99.9: 0.1 to 90: 10,
Wherein the amine compound having a hydrophilic group is 2,2-benzidine disulfonic acid.
17. The method of claim 16,
Wherein the amine compound having a hydrophilic group is contained in an amount of 0.006 to 0.6% by weight in the entire aqueous solution containing an amine compound.