KR20200038702A - Membrane, water treatment module, method of manufacturing membrane and composition for modifying active layer of membrane - Google Patents

Abstract

The present invention relates to a separator, a water treatment module, a manufacturing method of a separator and a composition for modifying an active layer of a separator. The separator comprises a porous layer and an active layer, and has an effect of improving the salt removal rate.

Description

Separation membrane, water treatment module, manufacturing method of separation membrane, and composition for modifying active layer of separation membrane

The present specification relates to a separation membrane, a water treatment module, a manufacturing method of the separation membrane, and a composition for modifying the active layer of the separation membrane.

The phenomenon that the solvent moves between the two solutions separated by the semi-permeable membrane through the separation membrane from a solution having a low solute concentration to a high solution is called an osmotic phenomenon, and at this time, the pressure acting on the side of the solution having a high solute concentration due to the movement of the solvent. Is called osmotic pressure. However, when an external pressure higher than the osmotic pressure is applied, the solvent moves toward a solution having a low solute concentration, and this phenomenon is called reverse osmosis. By using the reverse osmosis principle, various salts or organic substances can be separated through a semi-permeable membrane using a pressure gradient as a driving force. The water treatment separation membrane using the reverse osmosis phenomenon is used for separating molecular-level substances and removing salts from salt water or sea water to supply water for household, construction, and industrial use.

In the reverse osmosis membrane, salt removal rate and flow rate improvement are always important tasks, and especially in the case of SW (Sea water) separation membrane using high-density raw water, improvement of removal rate is more important. Research into improving the performance of the reverse osmosis membrane has been continuously conducted.

Korean Patent Publication No. 10-2013-0137238

The present specification relates to a separation membrane, a water treatment module, a method for manufacturing the separation membrane, and a composition for modifying the active layer of the separation membrane.

An exemplary embodiment of the present specification is a porous layer; And a separation membrane including an active layer, which is provided on the active layer, and further includes a membrane including a structure in which an amine group and sorbitol polyglycidyl ether of the active layer are covalently bonded.

Another embodiment of the present specification provides a water treatment module including the separator.

Another embodiment of the present specification is a porous layer; And contacting the composition for modifying the active layer of the separator comprising sorbitol polyglycidyl ether to the separator comprising the active layer. And forming a film on the active layer comprising a structure in which the amine group and the sorbitol polyglycidyl ether of the active layer are covalently bonded.

Another exemplary embodiment of the present specification provides a composition for modifying an active layer of a separator comprising sorbitol polyglycidyl ether.

When separating a high concentration of raw water with a separation membrane according to the present specification, there is an effect of improving the salt removal rate.

1 shows a separator according to an exemplary embodiment of the present specification.

When a member is referred to as being “on” another member in the present specification, this includes not only the case where one member abuts another member, but also another member between the two members.

In the present specification, when a part “includes” a certain component, it means that the component may further include other components, not to exclude other components, unless specifically stated otherwise.

Hereinafter, the present specification will be described in more detail.

An exemplary embodiment of the present specification is a porous layer; And a separation membrane including an active layer, which is provided on the active layer, and further includes a membrane including a structure in which an amine group and sorbitol polyglycidyl ether of the active layer are covalently bonded.

The active layer is formed by interfacial polymerization of an aqueous solution containing an amine compound and an organic solution containing an acyl halide compound. A large amount of amine groups are present on the surface of the active layer formed by the interfacial polymerization. That is, the amine group of the active layer is present on the surface of the active layer.

In general, the salt removal rate of the membrane may be influenced by the physical repelling force of a substance present on the membrane surface. When the amine group and the sorbitol polyglycidyl ether of the active layer include a covalent bond on the active layer included in the separation membrane according to the present specification, the covalent structure causes physical repulsion. Accordingly, the salt ions that are intended to pass through the separator cannot easily pass through the separator due to physical repulsion, thereby improving the salt removal rate of the separator.

When pre-treatment is performed with an aqueous solution containing DMAP (N, N-dimethylamino propylamine), a salt removal rate is formed on the active layer by forming a film containing a structure in which the amine group and sorbitol polyglycidyl ether of the active layer are covalently bonded. Can be degraded. This is because when the aqueous solution containing DMAP contacts the separator, the aqueous solution containing DMAP is basic and may cause chemical damage to the separator. In addition, when pre-treatment with an aqueous solution containing DMAP, physical damage to the separator may occur while undergoing additional processes such as rinsing and drying. Accordingly, the salt permeability of the separator increases rapidly due to chemical and / or physical damage of the separator caused by pretreatment of the aqueous solution containing the DMAP, and the salt removal rate may decrease.

On the other hand, the separation membrane according to an exemplary embodiment of the present specification is an aqueous solution containing the DMAP to prepare a membrane comprising a structure in which the amine group and the sorbitol polyglycidyl ether of the active layer are covalently bonded without conducting pretreatment, and thus use a salt in an economical manner. There is an effect that the removal rate can be improved.

In one embodiment of the present specification, the sorbitol polyglycidyl ether is represented by Formula 1 below.

[Formula 1]

In one embodiment of the present specification, the membrane including the structure in which the amine group and the sorbitol polyglycidyl ether of the active layer are covalently formed is formed of a composition for modifying the active layer of the separation membrane containing the sorbitol polyglycidyl ether.

The structure in which the amine group and the sorbitol polyglycidyl ether of the active layer is "covalently bonded" specifically refers to a form in which the amine group and the epoxy group of the sorbitol polyglycidyl ether are combined.

Specifically, the "covalent bond" means that an amine group on the surface of the active layer and the epoxy group of the sorbitol polyglycidyl ether are opened to share electrons to form a chemical bond.

For example, the structure in which the amine group of the active layer and the sorbitol polyglycidyl ether are covalently bonded may be represented by the following Chemical Formula 1-1.

[Formula 1-1]

는 상기 활성층의 표면에 아민기가 연결된 것을 의미한다.In Chemical Formula 1-1,

Means that an amine group is connected to the surface of the active layer.

The amine group of the active layer may be an amine group remaining in the active layer, or may be an amine group included in the polyamide constituting the active layer.

The epoxy group of the sorbitol polyglycidyl ether that reacts with the amine group of the active layer means at least one epoxy group included in the sorbitol polyglycidyl ether.

One embodiment of the present specification provides a composition for modifying an active layer of a separator comprising sorbitol polyglycidyl ether.

The composition for modifying the active layer of the separation membrane containing the sorbitol polyglycidyl ether may include the sorbitol polyglycidyl ether and a solvent.

In addition, the composition for modifying the active layer of the separator comprising the sorbitol polyglycidyl ether may further include an amine group of the active layer.

In one embodiment of the present specification, the weight average molecular weight of the sorbitol polyglycidyl ether contained in the composition for modifying the active layer of the separation membrane containing the sorbitol polyglycidyl ether is 100 g / mol to 1,000 g / mol. Preferably, the weight average molecular weight is 250 g / mol to 350 g / mol. Specifically, the weight average molecular weight is 294.30 g / mol.

When the weight average molecular weight of the sorbitol polyglycidyl ether falls within the above range, it is possible to sufficiently prevent the salt permeation of the separator and increase the salt removal rate, but the viscosity of the composition for modifying the active layer of the separator comprising the sorbitol polyglycidyl ether To keep it not too high, it does not cause process problems that can occur due to the high viscosity of the solution.

The weight-average molecular weight is a value obtained by averaging the molecular weights of the molecular weights of the component molecular species of the polymer compound having a molecular weight distribution as one of the average molecular weights in which the molecular weight is not uniform and the molecular weight of a certain polymer material is used as a standard.

The weight average molecular weight can be measured through Gel Permeation Chromatography (GPC) analysis.

The solvent of the composition for modifying the active layer of the separation membrane containing the sorbitol polyglycidyl ether may be water, but is not limited thereto, and a hydrophilic solvent may be used.

In one embodiment of the present specification, the active layer is a polyamide active layer.

The polyamide active layer may be formed by generating polyamide by interfacial polymerization and adsorbing on the porous layer while the amine compound and the acyl halide compound react upon contact of the amine compound and the acyl halide compound.

The contacting may be performed through a method such as dipping, spraying or coating. Interfacial polymerization conditions can be used without limitation those known in the art.

To form the polyamide active layer, an aqueous layer containing an amine compound may be formed on the porous layer. The method of forming an aqueous solution layer containing an amine compound on the porous layer is not particularly limited, and any method capable of forming an aqueous solution layer on the porous layer can be used without limitation. Specifically, a method of forming an aqueous solution layer containing an amine compound on the porous layer may include spraying, coating, dipping, dripping, coating, and the like.

At this time, the aqueous layer containing the amine compound may be further subjected to a step of removing the aqueous solution containing the excess amine compound, if necessary. The aqueous layer containing the amine compound formed on the porous layer may be non-uniformly distributed when there are too many aqueous solutions containing the amine compound present on the porous layer, and the aqueous solution containing the amine compound is distributed non-uniformly. In the case, a heterogeneous polyamide active layer may be formed by subsequent interfacial polymerization. Therefore, it is preferable to remove the excess aqueous solution after forming an aqueous solution layer containing an amine compound on the porous layer. Although the removal of the excess aqueous solution is not particularly limited, for example, it may be performed using a sponge, an air knife, nitrogen gas blowing, natural drying, or a compression roll.

In the aqueous solution containing the amine compound, the amine compound is not limited as long as it is an amine compound used in the production of a membrane, but for specific examples, m-phenylenediamine, p-phenylenediamine, 1,3,6 Preference is given to -benzenetriamine, 4-chloro-1,3-phenylenediamine, 6-chloro-1,3-phenylenediamine, 3-chloro-1,4-phenylenediamine or mixtures thereof. Specifically, the amine compound is m-phenylenediamine.

The solvent of the aqueous solution containing the amine compound may be water, acetone, dimethyl sulfoxide (DMSO), or 1-methyl-2-pyrrolidinone (NMP), hexamethylphosphoramide (HMPA). It can contain.

The content of the amine compound may be 1% by weight or more and 10% by weight or less based on the total weight of the composition. When the above content is satisfied, the desired salt removal rate and permeation flow rate can be secured in the present specification.

The polyamide active layer may be prepared by coating an aqueous solution containing an amine compound on the porous layer and then interfacial polymerization by contacting an organic solution containing an acyl halide compound.

The acyl halide compound is not limited as long as it can be used for the polymerization of polyamide, but as a specific example, an aromatic compound having 2 to 3 carboxylic acid halides, trimethoyl chloride, isophthaloyl chloride and terephthaloyl One or two or more mixtures selected from the group consisting of chlorides can be preferably used. Specifically, the acyl halide compound is trimezoyl chloride.

The content of the acyl halide compound may be 0.01 wt% or more and 0.5 wt% or less based on the total weight of the composition. When the above content is satisfied, the desired salt removal rate and permeation flow rate can be secured in the present specification.

The organic solvent included in the organic solution containing the acyl halide compound is an aliphatic hydrocarbon solvent, for example, a hydrophobic liquid that does not mix with water such as freons and hexane, cyclohexane, heptane, alkanes having 5 to 12 carbon atoms, For example, alkanes having 5 to 12 carbon atoms and mixtures thereof, such as IsoPar (Exxon), ISOL-C (SK Chem), and ISOL-G (Exxon) may be used, but are not limited thereto.

The content of the organic solvent may be 95 wt% to 99.99 wt% based on the total weight of the organic solution containing the acyl halide compound, but is not limited thereto. When the content is satisfied, when the content is satisfied, the desired salt removal rate and permeation flow rate can be secured.

The thickness of the polyamide active layer may be 10 nm to 1000 nm, but is not limited thereto. The thickness may be preferably 300 nm to 500 nm. When the thickness of the polyamide active layer satisfies the above range, when the content is satisfied, a salt removal rate and a permeate flow rate desired in the present invention can be secured.

In the present specification, the porous layer may include a first porous support and a second porous support.

As the first porous support, a nonwoven fabric may be used. Polyethylene terephthalate may be used as the material of the nonwoven fabric, but is not limited thereto.

The thickness of the nonwoven fabric may be 50 μm to 150 μm, but is not limited thereto. Preferably, the thickness may be 60 μm to 100 μm. When the thickness of the nonwoven fabric satisfies the above range, durability of the separation membrane including the porous layer may be maintained.

The second porous support may mean that a coating layer of a polymer material is formed on the first porous support. As the polymer material, for example, polysulfone, polyethersulfone, polycarbonate, polyethylene oxide, polyimide, polyetherimide, polyetheretherketone, polypropylene, polymethylpentene, polymethylchloride, and polyvinylidene fluoride Ride and the like may be used, but is not necessarily limited to these. Specifically, polysulfone can be used as the polymer material.

The thickness of the second porous support may be 20 μm to 100 μm, but is not limited thereto. Preferably, the thickness may be 30 μm to 50 μm. When the thickness of the coating layer satisfies the above range, durability of the separator including the porous layer including the second porous support may be properly maintained.

According to an example, the second porous support layer may be made of a polymer solution containing the polysulfone. The polymer solution containing the polysulfone, based on the total weight of the polymer solution containing the polysulfone, put polysulfone solids of 10% to 20% by weight in 80% to 90% by weight of solvent dimethylformamide It may be a homogeneous liquid obtained after melting at 80 ° C to 85 ° C for 12 hours, but the weight range is not limited to the above range.

When the polysulfone solid in the above range is included based on the total weight of the polymer solution containing the polysulfone, the durability of the separator including the second porous support may be appropriately maintained.

The second porous support may be formed by a method of casting. The casting means a solution casting method. Specifically, after dissolving the polymer material in a solvent, it may mean a method of displacing the solvent after being developed on a smooth, non-adhesive surface. Specifically, the method of substituting with the solvent may use a nonsolvent induced phase separation method. With the non-solvent-induced phase separation method, a polymer is dissolved in a solvent to form a uniform solution, molded into a certain shape, and then immersed in a non-solvent. After that, the interaction between diffusion of the non-solvent and the solvent is carried out, the composition of the polymer solution changes, and precipitation of the polymer occurs, thereby forming a portion of the solvent and the non-solvent into pores.

In one embodiment of the present specification, a protective layer may be further included on a film including a structure in which the amine group and the sorbitol polyglycidyl ether of the active layer are covalently bonded.

The protective layer may be prepared through a method in which a film containing a structure in which the amine group and sorbitol polyglycidyl ether of the active layer is covalently bonded is formed and then immersed in the composition for forming a protective layer.

The protective layer may be a coating layer coated with a hydrophilic polymer such as polyvinyl alcohol on the surface of the membrane including a structure in which the amine group and sorbitol polyglycidyl ether of the active layer are covalently bonded, or may be a coating layer containing polyalkylene oxide, It may be a hydrophobic coating layer containing fluorine, or may be a coating layer coated with an aqueous solution containing glycerin.

In one embodiment of the present specification, the composition for forming a protective layer may include 10% to 30% by weight of glycerin based on the total weight of the composition for forming a protective layer. Specifically, it may include 15% by weight to 25% by weight of glycerin based on the total weight of the composition for forming the protective layer.

The separation membrane of the present specification may further include a protective layer made of a composition for forming a protective layer containing glycerin in the above weight range, thereby minimizing a decrease in permeate flow rate and improving stain resistance and durability.

An exemplary embodiment of the present specification provides a separator having a salt removal rate of 99.87% to 99.95% of the separator under the conditions of sodium chloride (NaCl) 0.054 mol / m ³ (32,000 ppm), 5.5 MPa (800 psi) and 25 ° C. .

Specifically, the salt removal rate may be 99.87% to 99.91%.

In one embodiment of the present specification, sodium chloride (NaCl) 0.054 mol / m ³ (32,000 ppm), 5.5 MPa (800 psi), and the permeation flow rate of the separation membrane at 25 ° C. is 3.7 to 4.5 L / m ² · day . Specifically, the permeation flow rate is 3.7 to 4.3 L / m ² · day. More specifically, the permeation flow rate is 3.79 to 4.24 L / m ² · day.

In the present specification, the salt removal rate and the evaluation of the permeate flow rate can be measured after a 1 hour stabilization step at sodium chloride (NaCl) 0.054 mol / m ³ (32,000 ppm), 5.5 MPa (800 psi) and 25 ° C. conditions. .

Specifically, in order to measure the salt removal rate and the permeate flow rate of the separator according to the present specification, a water treatment module including a plate type permeable cell, a high pressure pump, a storage tank, and a cooling device may be used. After the separation membrane is installed in the permeation cell, a sufficient preliminary operation is performed for about 1 hour using tertiary distilled water to stabilize the evaluation equipment. After that, after confirming that the 0.054 mol / m ³ (32,000 ppm) aqueous sodium chloride solution was stabilized by operating the equipment at a flow rate of 5.5 MPa (800 psi), 4 L / min for about 1 hour, it was confirmed that the water was permeated at 25 ° C for 10 minutes. The amount of permeation can be calculated by measuring the amount, and the salt removal rate (%) can be calculated by analyzing the salt concentration before and after permeation using a conductivity meter.

The separation membrane may be used as a micro filtration membrane (Micro Filtration), an ultra filtration membrane (UltraFiltration), a nano filtration membrane (Nano Filtration) or a reverse osmosis membrane (Reverse Osmosis), and may be specifically used as a reverse osmosis membrane.

One embodiment of the present specification provides a water treatment module including the separator.

The water treatment module may include one or more of the separators. Specifically, the water treatment module may include one or more and 50 or less separators.

The specific type of the water treatment module is not particularly limited, and examples thereof include a plate & frame module, a tubular module, a hollow & fiber module, or a spiral wound module.

In addition, as long as the water treatment module includes the above-mentioned reverse osmosis membrane, other configurations and manufacturing methods are not particularly limited, and general means known in this field can be employed without limitation.

An exemplary embodiment of the present specification is a porous layer; And contacting the composition for modifying the active layer of the separator comprising sorbitol polyglycidyl ether to the separator including the active layer; And forming a film on the active layer comprising a structure in which the amine group and the sorbitol polyglycidyl ether of the active layer are covalently bonded.

In the method of manufacturing the separator, the above-described description may be applied to the porous layer and the active layer.

The porous layer; And in the step of contacting the composition for modifying the active layer of the separation membrane containing sorbitol polyglycidyl ether to the separation membrane comprising the active layer, the contact may be carried out by a method of coating.

The step of forming a film comprising a structure in which the amine group and the sorbitol polyglycidyl ether of the active layer are covalently bonded on the active layer is coated with the composition for modifying the active layer of the separation membrane containing the sorbitol polyglycidyl ether and reacted for 10 seconds. And, after performing the rinsing for 10 seconds, may further include the step of rinsing for 6 minutes in distilled water at 70 ℃.

In one embodiment of the present specification, the sorbitol polyglycidyl ether is included in an amount of 0.01 to 2% by weight based on the total weight of the composition for modifying the active layer of the separator comprising the sorbitol polyglycidyl ether.

When the content of the sorbitol polyglycidyl ether falls within the above range, the viscosity of the composition for modifying the active layer of the separation membrane containing the sorbitol polyglycidyl ether is maintained not too high to occur due to the high viscosity of the solution It does not cause any possible process problems.

When the sorbitol polyglycidyl ether is 1 to 2% by weight based on the total weight of the composition for modifying the active layer, hydrophilicity is increased due to an increase in the hydroxyl group included in the structure of the sorbitol polyglycidyl ether Thus, there is an effect that the permeation flow rate can be further improved.

1 illustrates the structure of a separator according to an exemplary embodiment of the present specification. 1, an aqueous solution containing an amine compound and an organic solution containing an acyl halide compound on the porous layer 10 are formed by interfacial polymerization, the active layer 11, and the amine group and sorbitol poly of the active layer on the active layer 11 A membrane 12 including a structure in which glycidyl ether is covalently bonded, and a separation membrane including a protective layer 13 formed by applying the composition for forming the protective layer on the membrane 12 are illustrated. The separation membrane according to an exemplary embodiment of the present specification includes a membrane 12 including a structure in which the amine group and the sorbitol polyglycidyl ether of the active layer are covalently bonded, thereby improving salt removal rate and permeation flow rate.

Hereinafter, examples will be described in detail to specifically describe the present specification. However, the embodiments according to the present specification may be modified in various other forms, and the scope of the present specification is not interpreted to be limited to the embodiments described below. The embodiments of the present specification are provided to more fully describe the present specification to those skilled in the art.

Example 1.

As a porous layer, a coating layer (polysulfone layer) was coated on a nonwoven fabric (polyethylene terephthalate) having a thickness of 80 μm to a thickness of 40 μm. The coating solution of the polysulfone layer was a homogeneous liquid with 15% by weight of polysulfone solid in 85% by weight of solvent dimethylformamide and stirred at 80 to 85 ° C for 12 hours. The coating method was a die coating method.

Then, a polyamide active layer was formed on the porous layer by an interfacial polymerization reaction of m-phenylenediamine (m-PD) and trimethoyl chloride (TMC).

Specifically, an aqueous solution layer was formed on the porous support layer using an aqueous solution containing 5% by weight of m-phenylenediamine. Subsequently, an organic solution containing 0.2% by weight of trimethoyl chloride (TMC) and 98% by weight of Isopar-G, an organic solvent, was applied on the aqueous solution layer to perform an interfacial polymerization reaction, and a polyamide having a thickness of 500 nm was formed. An active layer was prepared.

Then, based on the total weight of the composition for modifying the active layer of the separator, the composition for modifying the active layer containing 0.01% by weight of sorbitol polyglycidyl ether (SPGE) and 99.99% by weight of water was applied and reacted for 10 seconds, followed by 10 seconds. Rinse was performed.

Then, rinsing was performed in distilled water at 70 ° C. for 6 minutes, and then, to prepare a protective layer, a composition for forming a protective layer was prepared. The composition for forming the protective layer was prepared by adding 20% by weight of glycerin based on the total amount of the composition for forming the protective layer in distilled water and dissolving at 25 ° C for 1 hour to prepare a uniform liquid.

This solution was applied on a film prepared by applying the composition for modifying the active layer, and dried in an oven at 90 ° C. for 5 minutes to prepare a protective layer.

The thickness of the prepared porous layer and the active layer was averaged by measuring the cross-section of a sample of 0.2 cm ² through a microtome, coating the platinum (Pt), and measuring each thickness using a scanning electron microscope (SEM). It was confirmed by calculating by value.

Thus, the separator of Example 1 was prepared.

Examples 2 to 4

In Example 1, a separator was prepared in the same manner as in Example 1, except that the content of sorbitol polyglycidyl ether (SPGE) was applied as shown in Table 1 below.

SPGE content (% by weight) Example 1 0.01 Example 2 0.1 Example 3 One Example 4 2

Comparative Example 1

As a porous layer, a coating layer (polysulfone layer) was coated on a nonwoven fabric (polyethylene terephthalate) having a thickness of 100 µm to a thickness of 60 µm. The coating solution of the polysulfone layer was a homogeneous liquid with 15% by weight of polysulfone solid in 85% by weight of solvent dimethylformamide and stirred at 80 to 85 ° C for 12 hours. The coating method was a die coating method.

Then, a polyamide active layer was formed on the porous layer by an interfacial polymerization reaction of m-phenylenediamine (m-PD) and trimethoyl chloride (TMC).

Specifically, an aqueous solution layer was formed on the porous support layer using an aqueous solution containing 5% by weight of m-phenylenediamine. Subsequently, an organic solution containing 0.2% by weight of trimethoyl chloride (TMC) and 98% by weight of Isopar-G, an organic solvent, was applied on the aqueous solution layer to perform an interfacial polymerization reaction, and a polyamide having a thickness of 500 nm was formed. An active layer was prepared.

Then, to prepare a protective layer on the polyamide active layer, a composition for forming a protective layer was prepared. The composition for forming the protective layer was prepared by adding 20% by weight of glycerin based on the total amount of the composition for forming the protective layer in distilled water and dissolving at 25 ° C for 1 hour to prepare a uniform liquid.

This solution was applied on the polyamide active layer and dried in an oven at 90 ° C. for 5 minutes to prepare a protective layer.

The thickness of the prepared porous layer and the active layer was averaged by measuring the cross-section of a sample of 0.2 cm ² through a microtome, coating the platinum (Pt), and measuring each thickness using a scanning electron microscope (SEM). It was confirmed by calculating by value.

Thus, a separator of Comparative Example 1 was prepared.

Comparative Example 2

In Comparative Example 1, after preparing the polyamide active layer, it was pre-treated with an aqueous solution containing DMAP (N, N-dimethylamino propylamine). Based on the total weight of the aqueous solution containing DMAP, an aqueous solution containing 5% by weight of DMAP was applied on the polyamide active layer at 25 ° C., reacted for 10 seconds, and then rinsed for 10 seconds.

Then, to prepare a protective layer on the polyamide active layer, a composition for forming a protective layer was prepared. The composition for forming the protective layer was prepared by adding 20% by weight of glycerin based on the total amount of the composition for forming the protective layer in distilled water and dissolving at 25 ° C for 1 hour to prepare a uniform liquid.

This solution was applied on the polyamide active layer and dried in an oven at 90 ° C. for 5 minutes to prepare a protective layer.

The thickness of the prepared porous layer and the active layer was averaged by measuring the cross-section of a sample of 0.2 cm ² through a microtome, coating the platinum (Pt), and measuring each thickness using a scanning electron microscope (SEM). It was confirmed by calculating by value.

Thus, a separator of Comparative Example 2 was prepared.

Experimental example

(Evaluation of salt removal rate and permeation flow rate)

Sodium chloride (NaCl) 0.054 mol / m ³ (32,000 ppm), 5.5 MPa (800 psi) and after stabilization for 1 hour at 25 ° C., the separation membranes prepared according to Examples 1 to 4 and Comparative Examples 1 and 2 The salt removal rate was evaluated and described in Table 2 below.

Specifically, in order to measure the salt removal rate and the permeate flow rate of the separators prepared according to Examples 1 to 4 and Comparative Examples 1 and 2, a water treatment module including a flat-type permeable cell, a high-pressure pump, a storage tank, and a cooling device was used. .

The structure of the flat-type transmission cell was a cross-flow method, and the effective transmission area was 28 cm ² . After the separation membrane was installed in the permeation cell, preliminary operation was performed for about 1 hour using tertiary distilled water to stabilize the evaluation equipment. After that, it was confirmed that the 0.054 mol / m ³ (32,000 ppm) aqueous sodium chloride solution was stabilized by operating the equipment for about 1 hour at a flow rate of 5.5 MPa (800 psi), 4 L / min, and then permeated at 25 ° C. for 10 minutes. The permeate flux was calculated by measuring the amount of water, and the salt removal rate (%) was calculated by analyzing the salt concentration before and after permeation using a conductivity meter. The salt removal rate and the permeate flow rate thus measured are shown in Table 2 below.

Salt removal rate (%) Permeation flow rate (L / m ² · day) Example 1 99.87 3.88 Example 2 99.90 3.79 Example 3 99.90 4.17 Example 4 99.91 4.24 Comparative Example 1 99.86 3.98 Comparative Example 2 99.84 4.13

According to Table 2, it was confirmed that the salt removal rates of Examples 1 to 4 were higher than those of Comparative Examples 1 and 2. In addition, it was confirmed that the permeation flow rates of Examples 3 and 4 were higher than those of Comparative Examples 1 and 2. This is when the content of the sorbitol polyglycidyl ether as in Examples 3 and 4 is 1% by weight to 2% by weight based on the total weight of the composition for modifying the active layer, satisfies the salt removal rate of 99.9% or more while the permeation flow rate is 4.17 L / m ² · day or more was satisfied, and it was confirmed that the performance of the separator according to the present specification was excellent.

Although the preferred embodiment of the present invention has been described through the above, the present invention is not limited thereto, and can be implemented in various ways within the scope of the claims and detailed description of the invention, and this also belongs to the scope of the invention. .

10: porous layer
11: active layer
12: membrane comprising a structure in which the amine group and sorbitol polyglycidyl ether of the active layer are covalently bonded
13: protective layer

Claims (9)

Porous layer; And as a separation membrane comprising an active layer,
A separator provided on the active layer, further comprising a membrane comprising a structure in which the amine group and the sorbitol polyglycidyl ether of the active layer are covalently bonded. The method according to claim 1, wherein the sorbitol polyglycidyl ether is a separator represented by the formula (1):
[Formula 1]

The separator according to claim 1, wherein the active layer is a polyamide active layer. The method according to claim 1, The separation layer further comprises a protective layer on the membrane comprising a structure in which the amine group and the sorbitol polyglycidyl ether of the active layer is covalently bonded. The method according to claim 1, The sodium chloride (NaCl) 0.054 mol / m ³ , 5.5 MPa and the separation rate of the salt of the separation membrane at 25 ℃ conditions is 99.87% to 99.95%. A water treatment module comprising the separator according to claim 1. Porous layer; And contacting the composition for modifying the active layer of the separator comprising sorbitol polyglycidyl ether to the separator including the active layer; And
Comprising the step of forming a film comprising a structure covalently bonded to the amine group and the sorbitol polyglycidyl ether of the active layer on the active layer,
Method for producing a separator according to any one of claims 1 to 5. The method of claim 7, wherein the sorbitol polyglycidyl ether is contained in an amount of 0.01 to 2% by weight based on the total weight of the composition for modifying the active layer containing the sorbitol polyglycidyl ether. A composition for modifying an active layer of a separation membrane containing sorbitol polyglycidyl ether.

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