KR102504461B1 - Method for preparing multilayered ion exchange membrane using partial modification and the multilayered ion exchange membrane prepared by the same method - Google Patents

Abstract

The present invention relates to a method for manufacturing a multilayer ion exchange membrane using partial chemical modification and to the multilayer ion exchange membrane manufactured thereby, and more particularly, to a part of an acidic group such as a sulfonic acid group or a carboxyl group of a polymer ion exchange membrane for anion conductivity. It relates to a method for preparing a multilayer ion exchange membrane including an acid/base layer by partial modification with an ammonium group, which is a functional group, and a multilayer ion exchange membrane manufactured thereby.

Description

Method for preparing multilayered ion exchange membrane using partial modification and the multilayered ion exchange membrane prepared thereby {Method for preparing multilayered ion exchange membrane using partial modification and the multilayered ion exchange membrane prepared by the same method}

The present invention relates to a method for manufacturing a multilayer ion exchange membrane using partial chemical modification and to the multilayer ion exchange membrane manufactured thereby, and more particularly, to a part of an acidic group such as a sulfonic acid group or a carboxyl group of a polymer ion exchange membrane for anion conductivity. It relates to a method for preparing a multilayer ion exchange membrane including an acid/base layer by partial modification with an ammonium group, which is a functional group, and a multilayer ion exchange membrane manufactured thereby.

An ion exchange membrane refers to a polymer membrane that selectively passes anions or cations, and is classified into a cation exchange membrane and an anion exchange membrane according to surface charge characteristics. The cation exchange membrane has a negatively charged functional group (cationically conductive functional group), passes only cations by electrical attraction, and blocks the movement of anions by electrical repulsive force. In addition, the anion exchange membrane has a positively charged functional group (anionic conductive functional group), and has characteristics of moving anions by electrical attraction and blocking movement of cations by electrical repulsive force.

Such an ion exchange membrane should have excellent permselectivity as well as ion exchange capacity, low ion transfer resistance and diffusion coefficient, excellent electrochemical properties, and low manufacturing cost. In particular, ion exchange membranes in the field of water treatment and seawater desalination require superior ion selectivity and water permeability characteristics than conventional membranes.

Japanese Patent Publication 2001049009A Korean Patent Publication No. 10-2013-00255821 Korean Patent Publication No. 10-2014-0119479

The technical problem to be achieved by the present invention is to modify one side (amphiphilic membrane, bipolar membrane) or some layers of both surfaces with ammonium groups through a chemical modification process of an ion exchange membrane containing an acidic functional group such as a sulfonic acid group or a carboxylic acid group. It is to provide a method for manufacturing a multi-layered ion exchange membrane including alternating acid/base layers.

In addition, another technical problem of the present invention is to have a double layer or triple layer structure by modifying acidic functional groups of some layers of one or both surfaces of the ion exchange membrane with an ammonium group by a chemical modification reaction, and interfacial resistance between different layers when manufacturing a multilayer ion exchange membrane It is to provide an ion exchange membrane that can solve the problem and the problem of interfacial separation due to the application of the electrochemical system.

In addition, the present invention provides a multi-layered ion exchange membrane that includes alternating acid/base layers, so that the salt removal rate is excellent, the water permeability is high, and the performance can be maintained for a long period of time.

In order to solve the above problems, the present invention provides a method for producing a multilayer ion exchange membrane using partial modification, characterized in that a portion of the acidic group on one or both surfaces of the sulfonic acid polymer ion exchange membrane is modified with an ammonium group.

More specifically, the present invention is a method for preparing a multilayered ion exchange membrane by partially modifying the acidic groups of the polymeric ion exchange membrane with ammonium groups, wherein a) chlorination of some of the acidic groups of the polymeric ion exchange membrane or chlorination of the entire acidic groups of the polymeric ion exchange membrane is performed. Restoring a part after; b) nitrifying the ion exchange membrane on which the chlorination reaction has been performed; c) amination of the ion exchange membrane subjected to the nitrification reaction; and d) activating an ammonium group by alkalinizing the ion exchange membrane subjected to the amination reaction.

In addition, the present invention provides a multi-layered ion exchange membrane including a layered structure in which acid/base layers intersect by chemically modifying some of the acidic groups of the polymeric ion exchange membrane with ammonium groups.

According to the present invention, a multilayered ion exchange membrane in which heterogeneous functional groups having different charge characteristics have a layered structure can be prepared by selectively chemically modifying some of the sulfonic acid groups of the polymeric ion exchange membrane having an acidic group such as a sulfonic acid group or a carboxylic acid group. Depending on the field of application or use, it is possible to manufacture an ion exchange membrane composed of a double layer in the form of cation/anion, a triple layer in the form of cation/anion/cation, or a multi-layer structure of more than that, so the application potential is very wide. am.

In addition, in the present invention, since the electron density can be stabilized by introducing bridge groups in the chemical modification process, it is possible to solve the problem that the anionic conductive functional group applied to the terminal is chemically unstable due to the difference in electronegativity.

In addition, the chemical modification method according to the present invention can fundamentally block the interfacial resistance problem between heterogeneous layers and the delamination phenomenon occurring in multilayer separators manufactured by the physical thermal bonding method, thereby providing an ion exchange membrane that maintains long-term performance. there is.

1 is a graph showing water permeability over time of multilayer ion exchange membranes prepared according to Examples and Comparative Examples of the present invention.
2 is a graph showing salt removal rates over time of multilayer ion exchange membranes prepared according to Examples and Comparative Examples of the present invention.

The present invention will be described in more detail with reference to examples and drawings.

The method for manufacturing a multilayer ion exchange membrane according to the present invention is characterized by modifying a part of an acidic group such as a sulfonic acid group or a carboxyl group of a polymeric ion exchange membrane with an ammonium group, which is an anionic conductive functional group.

Looking at the manufacturing process step by step, the method for manufacturing a multilayered ion exchange membrane using partial modification according to the present invention is a method for preparing a multilayered ion exchange membrane by partially modifying the acid group of the polymeric ion exchange membrane with an ammonium group, comprising: a) the polymeric ion exchange membrane chlorination of some of the acidic groups or chlorination of all of the acidic groups and then restoring some of them; b) nitrifying the ion exchange membrane on which the chlorination reaction has been performed; c) amination of the ion exchange membrane subjected to the nitrification reaction; and d) alkalizing the ion exchange membrane where the amination reaction has been performed to activate an ammonium group, wherein the acidic group of the polymeric ion exchange membrane is a sulfonic acid group or a carboxylic acid group.

On the other hand, the multilayer ion exchange membrane according to the present invention is characterized in that it includes a layered structure in which acid/base layers cross each other by chemically modifying a part of a sulfonic acid group or a carboxylic acid group of a polymeric ion exchange membrane with an ammonium group. The multilayer ion exchange membrane according to the present invention may have a double-layered structure by modifying acid groups on one side of the polymeric ion exchange membrane with ammonium groups, or may have a triple-layered structure by modifying some of the acidic groups on both sides of the polymeric ion exchange membrane with ammonium groups. there is.

In the present invention, the ammonium group whose acidic group is substituted by chemical modification may be any of a primary ammonium group, a secondary ammonium group, a tertiary ammonium group, or a quaternary ammonium group. In the present invention, the ammonium group may be represented by [Formula 1] -NR ₁ R ₂ R ₃ , and the primary ammonium group is a functional group in which each of R ₁ , R ₂ and R ₃ is a hydrogen atom (ie, -NH ₃ ⁺ ), A secondary ammonium group refers to a functional group in which R ₁ and R ₂ are each a hydrogen atom and R ₃ is an alkyl or aryl group. A tertiary ammonium group is a functional group in which R ₁ is a hydrogen atom and R ₂ and R ₃ are each an alkyl or aryl group, and a quaternary ammonium group is a group in which R ₁ , R ₂ and R ₃ are each an alkyl or aryl group (ie, R ₁ , R ₂ and R ₃ are not hydrogen atoms).

Hereinafter, the chemical modification process of the present invention is described using a reaction formula, but the reaction formula is only illustrative, and the scope of the present invention is not limited to the following reaction formula.

[Scheme 1]

The method for manufacturing a multilayer ion exchange membrane according to the present invention may proceed according to Scheme 1 above, specifically, step 1: partial chlorination (-OH → -Cl) or partial restoration after full chlorination, step 2: Nitration (-Cl → -NO ₂ ), Step 3: Amination (-NO ₂ → -NH ₂ ), Step 4: Alkali treatment (-NH ₂ → -NH ₃ ⁺ ), chemical modification can be made.

At this time, the partial chlorination reaction in the first step may be performed on only one side of the ion exchange membrane, or may be controlled to be performed on only some layers on both sides of the ion exchange membrane, or partial reforming may be performed by restoring a part after the chlorination reaction as a whole. may be Accordingly, a multilayer ion exchange membrane in which an acid layer and a base layer, that is, a sulfonic acid base layer or a carboxyl base layer and an ammonium base layer are formed in a layered structure can be manufactured.

Polymer ion exchange membranes usable in the present invention include ion exchange membranes based on perfluorine-based sulfonic acid ionomers or perfluorine-based carboxylic acid ionomers or ion exchange membranes based on hydrocarbon-based sulfonic acid ionomers or hydrocarbon-based carboxylic acid ionomers. As the ion exchange membrane, a reinforced composite membrane including a porous support may also be used.

Specifically, as the perfluorine-based sulfonic acid ionomer or perfluorine-based carboxylic acid-based polymeric ion exchange membrane, for example, poly(perfluorosulfonic acid) or poly(perfluorocarboxylic acid), including a sulfonic acid group or a carboxylic acid group copolymers of tetrafluoroethylene and fluorovinyl ether, and mixtures thereof, but are not limited thereto.

In addition, hydrocarbon-based sulfonic acid ionomers or hydrocarbon-based carboxylic acid-based polymeric ion exchange membranes include, for example, carboxylated polyaryl ether sulfone, carboxylated polystyrene, carboxylated polyarylene ether ketone, and carboxylated polyether ketone. , sulfonated polyimide, sulfonated polyaryl ether sulfone, sulfonated polyether ether ketone, sulfonated polybenzimidazole, sulfonated polysulfone, sulfonated polystyrene, sulfonated polyphosphazene, sulfonated polyether ether sulfone, alcohol sulfonated polyethersulfone, sulfonated polyetherbenzimidazole, sulfonated polyarylene ether ketone, sulfonated polyether ketone, sulfonated polyimidazole, sulfonated polyether ketone ketone, sulfonated polyarylether benzimidazole and these One or more may be selected from the group consisting of a homopolymer, an alternating copolymer, a random copolymer, a block copolymer, a multi-block copolymer, and a graft copolymer of, but is not limited thereto.

In addition, when a reinforced composite membrane including a porous support is used as a polymer ion exchange membrane, usable porous supports include, for example, polyterafluoroethylene, polyvinylidene fluoride, polyethylene, polypropylene, polyethylene terephthalate, and polyimide. , polyamic acid and polymers such as polyamide, but are not particularly limited thereto.

Specifically, the chemical modification process according to the present invention will be described in detail step by step. First, in the step of a) chlorination, a polymer ion exchange membrane having an acidic group such as a sulfonic acid group or a carboxyl group is converted to SOCl ₂ , MeSO ₂ Cl, PCl ₅ , POCl ₃ , NH ₄ Cl, HCl, dichloromethane (DCM) 1 selected from the group consisting of It may be carried out by treatment with a solution containing more than one kind of compound, but is not limited thereto, and any solution capable of chlorinating an acidic group may be used.

In addition, the chlorination reaction is preferably carried out at 10 to 110 ° C., and the reaction time can be selectively adjusted depending on the degree of chemical modification of the acidic group, but is generally about 30 seconds to 8 hours.

At this time, if only one side of the polymeric ion exchange membrane having an acidic group is treated so that the chlorination reaction proceeds, a double-layer ion exchange membrane including an acidic base layer such as a sulfonic acid base layer or a carboxyl base layer and an ammonium base layer can be prepared. The polymeric ion exchange membrane is immersed in a solution to obtain Even if the chlorination reaction is performed on both surfaces, an ion exchange membrane having a triple layer structure of ammonium group/sulfonic acid group or carboxyl group/ammonium group can be prepared by chemically modifying only the surface thinly by controlling the reaction time.

After the chlorination reaction, the reaction of introducing an ammonium group undergoes a nitrification reaction in which a bridge group and a -NO ₂ group are introduced according to [Scheme 1]. The nitrification reaction may be performed by treating the perfluorine-based ion exchange membrane on which the chlorination reaction has been performed with a nitromethane or nitrobenzene solution, but is not limited thereto, and any solution capable of replacing -Cl with -NO ₂ can be used. do. Meanwhile, in the nitrification reaction, a bridging group such as a methyl group or a phenyl group is introduced by treatment with nitromethane, nitrobenzene, or the like.

At this time, the nitrification reaction is preferably carried out in the presence of a catalyst of the group consisting of sodium carbonate (Na ₂ CO ₃ ). In addition, the nitrification reaction is preferably carried out at 10 to 110 ° C., and the reaction time is appropriately 30 seconds to 12 hours.

Then, a step of replacing the chlorine group of the ion exchange membrane into which the bridge group has been introduced with an ammonium group is performed, which includes an amination reaction and an alkalization reaction step.

The amination reaction may be performed by treating the ion exchange membrane on which the nitrification reaction has been performed with, for example, an aqueous HCl solution, but is not limited thereto, and any solution capable of replacing -NO ₂ with -NH ₂ may be used. . The amination reaction is preferably carried out at 10 to 100 ° C., and the reaction time is appropriately about 30 seconds to 12 hours.

Then, the alkalization reaction may be performed by treating the ion exchange membrane where the amination reaction has been performed with an aqueous solution containing at least one compound selected from the group consisting of, for example, LiOH, NaOH, and KOH, but is not particularly limited thereto. , any solution capable of substituting -NH ₂ for -NH ₃ ⁺ can be used. The alkalization reaction is preferably carried out at 10 to 110 ° C., and the reaction time is appropriately about 30 seconds to 12 hours.

In addition, in the process of chemically modifying a sulfonic acid group into an ammonium group according to the present invention, the chlorination, nitrification, amination, and alkalization reaction steps may further include washing and drying steps after each reaction step is performed.

In the chemical modification method according to the present invention, the reaction temperature and time range of each step can be appropriately adjusted as needed, but partial modification is required to form a multilayer film, so when the reaction proceeds beyond the temperature and time range, the desired layer structure You can't get it, so be careful.

The multilayered ion exchange membrane according to the present invention includes a layered structure in which acid/base layers cross each other by chemically modifying a part of a sulfonic acid group or a carboxylic acid group of a polymeric ion exchange membrane with an ammonium group. The multilayer ion exchange membrane may have a double-layered structure by modifying acidic groups on one side of the polymeric ion exchange membrane with ammonium groups, or may have a triple-layered structure by modifying some of the acidic groups on both sides of the polymeric ion exchange membrane with ammonium groups.

In addition, the ammonium group of the ion exchange membrane chemically modified according to the present invention may be bonded to the -SO ₂ functional group of the sulfonic acid polymer ion exchange membrane through a bridge group selected from a methyl group or a phenyl group. The water permeability of the multilayer ion exchange membrane partially modified with ammonium groups according to the present invention is 14.51 - 15.61 10 ^-12 m/s.Pa, and the salt removal rate is in the range of 99.49 - 99.99%, which is excellent in performance and characteristics.

Hereinafter, the present invention will be described in more detail through specific examples. However, the following examples are presented by way of example to aid understanding of the present invention and should not be construed as limiting the scope of the present invention thereto.

<Example 1>

In the chlorination reaction, which is the first step of Scheme 1, 5 g/mL SOCl ₂ /dichloromethane was stirred at 400 rpm in a nitrogen atmosphere at 40 ^° C, and Nafion 117, a perfluorinated sulfonic acid ionomer-based ion exchange membrane (film thickness 175 μm) was reacted for 4 hours. After the reaction, the mixture was washed with dichloromethane for 5 minutes and dried in a vacuum oven at 80 ^° C for 4 hours.

Next, in the nitrification reaction in the second step, the nitromethane solution was stirred at a speed of 200 rpm in a nitrogen atmosphere at 110 ^° C, and sodium carbonate as a catalyst was added at 20 wt% based on the weight of the ion exchange membrane obtained after the first step, followed by chlorination. The reacted Nafion 117 was allowed to react for 30 seconds. Then, it was washed with ultrapure water for 3 hours and dried in a vacuum oven at 80 ^° C for 4 hours.

Next, in the third step of the amination reaction, a 1 M HCl solution at 100 ^° C was stirred at a speed of 200 rpm, and the Nafion 117 subjected to the nitrification reaction was reacted for 30 seconds, followed by washing with ultrapure water for 3 hours, It was dried in a vacuum oven at 80 ^° C for 4 hours.

Finally, in the 4-step alkalization reaction, a 1 M KOH solution was stirred at a speed of 200 rpm at 110 ^° C, and the aminated Nafion 117 was reacted for 30 seconds, followed by washing with ultrapure water for 3 hours. Then dried in a vacuum oven at 80 ^° C for 4 hours.

<Example 2>

In the chlorination reaction, which is the first step of Scheme 1, 5 g/mL of PCl ₅ /POCl ₃ was stirred at 400 rpm in a nitrogen atmosphere at 110 ^o C, and the hydrocarbon-based sulfonic acid ionomer-based sulfonated aryl ether sulfone membrane was formed for 30 seconds reacted while After the reaction, the mixture was washed with dichloromethane for 5 minutes and dried in a vacuum oven at 80 ^° C for 4 hours.

Next, in the second stage of the nitrification reaction, the nitromethane solution was stirred at a rate of 200 rpm in a nitrogen atmosphere at 80 ^° C, and sodium carbonate as a catalyst was added at 20 wt% relative to the weight of the sulfonated arylethersulfone membrane obtained after the first stage, Then, the sulfonated arylethersulfone film subjected to the chlorination reaction was reacted for 7 hours. Then, it was washed with ultrapure water for 3 hours and dried in a vacuum oven at 80 ^° C for 4 hours.

Then, in the third step of the amination reaction, a 0.5 M HCl solution at 50 ^° C was stirred at a speed of 200 rpm, and the sulfonated arylethersulfone film subjected to the nitrification reaction was reacted for 3 hours, followed by washing with ultrapure water for 3 hours and dried in a vacuum oven at 80 ^° C for 4 hours.

Finally, in the fourth step of the alkalization reaction, a 0.5 M KOH solution was stirred at a rate of 200 rpm at 50 ^o C, and the aminated sulfonated arylethersulfone membrane was reacted for 3 hours, followed by the reaction with ultrapure water for 3 hours. After washing, it was dried in a vacuum oven at 80 ^° C for 4 hours.

<Example 3>

In the first step of the chlorination reaction of Reaction Scheme 1, 5 g/mL SOCl ₂ /dichloromethane was stirred at 400 rpm in a nitrogen atmosphere at 10 ^o C, and a sulfonated styrene membrane, an ion exchange membrane based on a carbon-based sulfonic acid ionomer, was 8 reacted over time. After the reaction, the mixture was washed with dichloromethane for 5 minutes and dried in a vacuum oven at 80 ^° C for 4 hours.

One side of the ion exchange membrane subjected to the chlorination reaction was exposed to a 1 M aqueous solution of potassium hydroxide at room temperature, and then stirred and reacted at a speed of 100 rpm for 6 hours to restore the sulfonic acid group.

Next, in the nitrification reaction in the second step, the nitromethane solution was stirred at a speed of 200 rpm in a nitrogen atmosphere at 10 ^° C, sodium carbonate as a catalyst was added at 20 wt% based on the weight of the ion exchange membrane obtained after the first step, and the chlorination reaction was performed. The rough ion exchange membrane was reacted for 12 hours. Then, it was washed with ultrapure water for 3 hours and dried in a vacuum oven at 80 ^° C for 4 hours.

Next, in the third step of the amination reaction, a 0.5 M HCl solution at 10 ^° C was stirred at a speed of 200 rpm, and the ion exchange membrane subjected to the nitrification reaction was reacted for 12 hours, washed with ultrapure water for 3 hours, and 80 It was dried in an ^o C vacuum oven for 4 hours.

Finally, in the 4-step alkalization reaction, a 0.5 M KOH solution was stirred at 200 rpm at 10 ^o C, and the aminated ion exchange membrane was reacted for 12 hours, washed with ultrapure water for 3 hours, and then It was dried in a vacuum oven at 80 ^° C for 4 hours.

<Example 4>

In the chlorination reaction, which is the first step of Scheme 1, 5 g/mL of PCl ₅ /POCl ₃ was stirred at 400 rpm in a nitrogen atmosphere at 110 ^o C, and Nafion 212, a perfluorine-based sulfonic acid ionomer-based reinforced film, was coated on only one side. Reacted for 30 seconds. After the reaction, the mixture was washed with dichloromethane for 5 minutes and dried in a vacuum oven at 80 ^° C for 4 hours.

Next, in the nitrification reaction of the second step, the nitromethane solution was stirred at a speed of 200 rpm in a nitrogen atmosphere at 110 ^° C, and sodium carbonate as a catalyst was added at 20 wt% based on the weight of the ion exchange membrane obtained after the first step. Nafion 212 subjected to surface chlorination was reacted for 30 seconds. Then, it was washed with ultrapure water for 3 hours and dried in a vacuum oven at 80 ^° C for 4 hours.

Next, in the third step of the amination reaction, a 1 M HCl solution at 100 ^° C was stirred at a speed of 200 rpm, and the Nafion 212 subjected to the nitrification reaction was reacted for 30 seconds, followed by washing with ultrapure water for 3 hours, It was dried in a vacuum oven at 80 ^° C for 4 hours.

Finally, in the fourth step of the alkalization reaction, a 1 M KOH solution was stirred at a rate of 200 rpm at 110 ^° C, and Nafion 212, which had undergone the amination reaction, was reacted for 30 seconds, and washed with ultrapure water for 3 hours. Then dried in a vacuum oven at 80 ^° C for 4 hours.

<Example 5>

In the chlorination reaction, which is the first step of Scheme 1, 0.25 g/g of NH ₄ /HCl was stirred at a rate of 400 rpm in a nitrogen atmosphere at 100 ^o C, and Nafion 211, a perfluorinated sulfonic acid ionomer-based reinforced film, was coated with only one side of 30 reacted for seconds. After the reaction, the mixture was washed with dichloromethane for 5 minutes and dried in a vacuum oven at 80 ^° C for 4 hours.

Next, in the nitrification reaction of the second step, the nitromethane solution was stirred at a speed of 200 rpm in a nitrogen atmosphere at 110 ^° C, and sodium carbonate as a catalyst was added at 20 wt% based on the weight of the ion exchange membrane obtained after the first step. Nafion 211 subjected to surface chlorination was reacted for 30 seconds. Then, it was washed with ultrapure water for 3 hours and dried in a vacuum oven at 80 ^° C for 4 hours.

Next, in the third step of the amination reaction, a 1 M HCl solution at 100 ^° C was stirred at a speed of 200 rpm, and the Nafion 211 subjected to the nitrification reaction was reacted for 30 seconds, followed by washing with ultrapure water for 3 hours, It was dried in a vacuum oven at 80 ^° C for 4 hours.

Finally, in the 4-step alkalization reaction, a 1 M KOH solution was stirred at a speed of 200 rpm at 110 ^° C, and Nafion 211, which had undergone the amination reaction, was reacted for 30 seconds, and washed with ultrapure water for 3 hours. Then dried in a vacuum oven at 80 ^° C for 4 hours.

<Example 6>

A multilayer ion exchange membrane was prepared in the same manner as in Example 4, except that the perfluorine-based sulfonic acid ion exchange membrane was used as the reinforced composite membrane, Nafion 117-PFM.

<Example 7>

A multilayer ion exchange membrane was prepared in the same manner as in Example 1, except that 3M 725 was used as the perfluorine-based sulfonic acid ion exchange membrane.

<Example 8>

A multilayer ion exchange membrane was prepared in the same manner as in Example 1, except that the sulfonic acid polymer ion exchange membrane was replaced with a carboxylic acid polymer ion exchange membrane.

<Comparative Example 1>

An ion exchange membrane based on Cellulose acetate (CA) commercially available from HTI was used.

<Comparative Example 2>

An ion exchange membrane based on Cellulose triacetate (CTA) commercially available from HTI was used.

<Comparative Example 3>

A polyamide (PA)-based thin-film composite (TFC) type ion exchange membrane commercially available from DOW was used.

<Comparative Example 4>

A PA-based TFC type ion exchange membrane commercially available from DOW was used.

<Comparative Example 5>

WSI was used as a commercially available double layer ion exchange membrane from Tokuyama Soda.

<Experimental Example 1> Measurement of water permeability and salt removal rate

In order to evaluate the performance of the membranes prepared in Examples and Comparative Examples, a certain pressure was applied to a unit area to pass NaCl aqueous solution at a concentration of 0.5 M, and water permeability was evaluated through the degree of purification and the permeated flow rate.

The operational performance of the water treatment ion exchange membrane can be confirmed through water permeability and salt removal rate. That is, the higher the water permeability and salt removal rate of the ion exchange membrane, the better the performance. Accordingly, the water permeability and salt rejection of the multilayer ion exchange membrane prepared according to the above example and the commercially available ion exchange membrane as a comparative example were measured over time.

As can be seen in [Table 1] and [Table 2] and [Figure 1] and [Figure 2], compared to the commercial ion exchange membrane used as a comparative example, the multilayer ion exchange membrane partially modified according to the present invention It can be seen that the performance varies from about 3 times to 5 times, and over time, the gap in performance widens depending on the degree of contamination or durability of the ion exchange membrane. That is, it can be seen that the performance of the existing double-layer ion exchange membrane deteriorates over time due to the peeling phenomenon between the layers, but the multi-layer ion exchange membrane chemically modified according to the present invention shows continuous performance.

Claims (23)

A method for producing a triple layer ion exchange membrane for water treatment comprising a layered structure in which an acid layer and a base layer intersect by partially modifying a sulfonic acid group or a carboxylic acid group of a polymer ion exchange membrane with an ammonium group,
a) chlorinating some of the sulfonic acid groups or carboxylic acid groups on both sides of the polymeric ion exchange membrane;
b) nitrifying the ion exchange membrane on which the chlorination reaction has been performed;
c) amination of the ion exchange membrane subjected to the nitrification reaction; and
d) activating an ammonium group by alkalinizing the ion exchange membrane subjected to the amination reaction. delete According to claim 1,
The method of manufacturing a triple layer ion exchange membrane for water treatment, characterized in that the ammonium group is selected from a primary ammonium group, a secondary ammonium group, a tertiary ammonium group, or a quaternary ammonium group. delete delete According to claim 1,
A method for producing a triple layer ion exchange membrane for water treatment, characterized in that a bridge group is introduced in the nitrification reaction step b). According to claim 6,
The bridge group is a method for producing a triple layer ion exchange membrane for water treatment, characterized in that selected from a methyl group or a phenyl group. According to claim 1,
The method of manufacturing a triple layer ion exchange membrane for water treatment, characterized in that the polymer ion exchange membrane is an ion exchange membrane based on a perfluorine-based ionomer or a hydrocarbon-based ionomer. According to claim 8,
The perfluorine-based ionomer is composed of poly(perfluorosulfonic acid), poly(perfluorocarboxylic acid), a copolymer of tetrafluoroethylene and fluorovinyl ether containing a sulfonic acid group or a carboxylic acid group, or a mixture thereof. A method for producing a triple layer ion exchange membrane for water treatment, characterized in that it is selected from the group. According to claim 8,
The hydrocarbon-based ionomer is carboxylated polyarylethersulfone, carboxylated polystyrene, carboxylated polyaryleneetherketone, carboxylated polyetherketone, sulfonated polyimide, sulfonated polyarylethersulfone, sulfonated polyether Ether ketone, sulfonated polybenzimidazole, sulfonated polysulfone, sulfonated polystyrene, sulfonated polyphosphazene, sulfonated polyetherethersulfone, sulfonated polyethersulfone, sulfonated polyetherbenzimidazole, sulfonated polyaryl ene ether ketone, sulfonated polyether ketone, sulfonated polyimidazole, sulfonated polyether ketone ketone, sulfonated polyarylether benzimidazole and their homopolymers, alternating copolymers, random copolymers, block copolymers, A method for producing a triple layer ion exchange membrane for water treatment, characterized in that it is selected from the group consisting of multi-block copolymers, graft copolymers, and mixtures thereof. According to claim 1,
The method of manufacturing a triple layer ion exchange membrane for water treatment, characterized in that the polymer ion exchange membrane is a reinforced composite membrane comprising a porous support. According to claim 11,
The porous support of the reinforced composite membrane is for water treatment, characterized in that selected from the group consisting of polyterafluoroethylene, polyvinylidene fluoride, polyethylene, polypropylene, polyethylene terephthalate, polyimide, polyamic acid and polyamide. Method for producing a triple layer ion exchange membrane. A triple layer ion exchange membrane for water treatment comprising a layered structure in which an acid layer and a base layer intersect by partially modifying a sulfonic acid group or a carboxylic acid group of the polymeric ion exchange membrane by the method according to claim 1 with an ammonium group. delete delete According to claim 13,
The ammonium group is a triple layer ion exchange membrane for water treatment, characterized in that selected from a primary ammonium group, a secondary ammonium group, a tertiary ammonium group, or a quaternary ammonium group. According to claim 13,
The ammonium group is a triple layer ion exchange membrane for water treatment, characterized in that connected to the ion exchange membrane through a bridge group. According to claim 17,
The bridge group is a triple layer ion exchange membrane for water treatment, characterized in that selected from a methyl group or a phenyl group. According to claim 13,
The polymer ion exchange membrane is a three-layer ion exchange membrane for water treatment, characterized in that the perfluorine-based ionomer or hydrocarbon-based ionomer-based ion exchange membrane. According to claim 19,
The perfluorine-based ionomer is composed of poly(perfluorosulfonic acid), poly(perfluorocarboxylic acid), a copolymer of tetrafluoroethylene and fluorovinyl ether containing a sulfonic acid group or a carboxylic acid group, or a mixture thereof. A triple layer ion exchange membrane for water treatment, characterized in that it is selected from the group. According to claim 19,
The hydrocarbon-based ionomer is carboxylated polyarylethersulfone, carboxylated polystyrene, carboxylated polyaryleneetherketone, carboxylated polyetherketone, sulfonated polyimide, sulfonated polyarylethersulfone, sulfonated polyether Ether ketone, sulfonated polybenzimidazole, sulfonated polysulfone, sulfonated polystyrene, sulfonated polyphosphazene, sulfonated polyetherethersulfone, sulfonated polyethersulfone, sulfonated polyetherbenzimidazole, sulfonated polyaryl ene ether ketone, sulfonated polyether ketone, sulfonated polyimidazole, sulfonated polyether ketone ketone, sulfonated polyarylether benzimidazole and their homopolymers, alternating copolymers, random copolymers, block copolymers, A triple layer ion exchange membrane for water treatment, characterized in that it is selected from the group consisting of multi-block copolymers, graft copolymers, and mixtures thereof. According to claim 13,
The polymeric ion exchange membrane is a triple layer ion exchange membrane for water treatment, characterized in that the reinforced composite membrane comprising a porous support. The method of claim 22,
The porous support of the reinforced composite membrane is for water treatment, characterized in that selected from the group consisting of polyterafluoroethylene, polyvinylidene fluoride, polyethylene, polypropylene, polyethylene terephthalate, polyimide, polyamic acid and polyamide. Trilayer ion exchange membrane.

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