KR20100018759A - Manufacturing method of heterogeneous ion exchange membrane, heterogeneous ion exchange structures and manufacturing method of heterogeneous ion exchange structures - Google Patents

Abstract

PURPOSE: A manufacturing method of a heterogeneous ion exchange membrane, a heterogeneous ion exchange structure and a manufacturing method thereof are provided to uniformly form the thickness of the heterogeneous ion exchange membrane. CONSTITUTION: A manufacturing method of a heterogeneous ion exchange membrane comprises a step for forming slurry by mixing ion exchange resin, a polymer binder, an additive and a solvent, and a forming the ion exchange membrane by applying the slurry with a tape casting method. The polymer binder is PVB. The additive includes one or more components among a dispersing agent, a hydrophobic polymer or a plasticizer.

Description

Manufacturing method of heterogeneous ion exchange membrane, heterogeneous ion exchange structures and manufacturing method of heterogeneous ion exchange structures

The present invention relates to a heterogeneous ion exchange membrane, and more particularly to a method for producing a heterogeneous ion exchange membrane, a heterogeneous ion exchange structure and a method for producing a heterogeneous ion exchange structure.

Ion-exchange membranes are membranes that selectively permeate ions and can be classified into homogeneous and heterogeneous membranes according to their structure. Depending on the purpose, ion-exchange membranes can be classified into desalting membranes, concentrated membranes, specially selected permeable membranes, and electrolyte membranes.

Since the ion exchange membrane selectively permeates ions, it is applied to an electrodeionization apparatus or an electrodialysis apparatus for removing an electrolyte in water.

However, the conventional homogeneous ion exchange membrane has a low density and low mechanical strength, and has a disadvantage of being produced at high temperature. In addition, since the thickness control is difficult, there is a problem that the large area is difficult.

DISCLOSURE OF THE INVENTION An object of the present invention for solving the above problems is to provide a method for producing a heterogeneous ion exchange membrane capable of large area with improved thickness uniformity, a heterogeneous ion exchange structure including the ion exchange membrane, and a method for producing the heterogeneous ion exchange structure. It is.

The present invention for achieving the above object is to form a slurry by mixing an ion exchange resin, a polymer binder, an additive and a solvent, the ion comprising a step of applying the slurry using a tape casting method to form an ion exchange membrane It provides a method for producing an exchange membrane.

The polymer binder may be poly (vinyl butyral) (PVB), and the additive may include at least one or more of a dispersant, a hydrophobic polymer, or a plasticizer. The hydrophobic polymer may be PVC, PE or PP.

The ion exchange resin is a cation exchange resin, the cation exchange resin may be 30 to 60% by weight based on the weight sum of the cation exchange resin and the polymer binder.

The ion exchange resin is an anion exchange resin, the anion exchange resin may be 10 to 40% by weight based on the weight sum of the anion exchange resin and the polymer binder.

A slurry formed by mixing an ion exchange resin, a polymer binder, an additive, and a solvent is disposed between the first ion exchange membrane and the second ion exchange membrane and the first ion exchange membrane and the second ion exchange membrane formed by applying a tape casting method. It provides a non-homogeneous ion exchange structure comprising a fiber network.

Mixing an ion exchange resin, a polymer binder, an additive and a solvent to form a slurry, applying the slurry using a tape casting method to form a first ion exchange membrane and a second ion exchange membrane, and the first ion exchange membrane and It provides a method for producing a heterogeneous ion exchange structure comprising positioning and bonding the fiber network between the second ion exchange membrane.

The ion exchange membranes and the fiber network may be bonded using a thermocompression method.

As described above, an ion exchange membrane was formed by applying a slurry containing the ion exchange resin particles and the polymer binder using a tape casting method. As a result, not only can the thickness of the ion exchange membrane be reduced, but also the thickness of the ion exchange membrane can be formed uniformly, so that a large area can be achieved.

By using PVB as the polymer binder, an ion exchange membrane can be formed even at a low temperature. Therefore, the electrical performance of the ion exchange membrane can be improved.

In addition, by optimizing the weight ratio of the ion exchange resin particles and the polymer binder, the electrical performance and mechanical strength of the ion exchange membrane can be improved together.

As the invention allows for various changes and numerous embodiments, particular embodiments will be illustrated in the drawings and described in detail in the written description.

However, this is not intended to limit the present invention to specific embodiments, it should be understood to include all modifications, equivalents, and substitutes included in the spirit and scope of the present invention.

Hereinafter, with reference to the accompanying drawings, it will be described in detail a preferred embodiment of the present invention. Hereinafter, the same reference numerals are used for the same components in the drawings, and duplicate descriptions of the same components are omitted.

1 is a cross-sectional view showing a heterogeneous ion exchange structure according to an embodiment of the present invention.

Referring to FIG. 1, a heterogeneous ion exchange structure 20 according to an embodiment of the present invention includes a first ion exchange membrane 12, a second ion exchange membrane 16, and a fiber network 14 disposed therebetween. can do. The fiber network 14 may improve the strength compared to the case where the ion exchange membrane is formed in a single.

The ion exchange membranes 12 and 16 may be formed by applying a slurry containing ion exchange resin particles, a polymer binder, an additive, and a solvent by using a tape casting method, and then removing the solvent. The thickness of the ion exchange membranes 12 and 16 may be reduced by forming the ion exchange membranes 12 and 16 using the tape casting method. In addition, even when the ion exchange membranes 12 and 16 are implemented in a large area, they may be formed to have a uniform thickness.

Bonding the ion exchange membranes 12 and 16 and the fiber network 14 may be performed using a thermocompression method. The thermocompression may improve the density and mechanical strength of the ion exchange structure 20, and may make the ion exchange structure 20 flexible.

Figure 2 is a schematic diagram showing an electric deionization device having a heterogeneous ion exchange structure according to an embodiment of the present invention.

Referring to FIG. 2, the heterogeneous ion exchange structure 20 may be an anion exchange structure 22 or a cation exchange structure 24. Such ion exchange structures 20 can be used in an electric deionizer.

When the heterogeneous ion exchange structures 22 and 24 are used in an electrodeionization device, the electrodeionization device may have a spacer 23 formed between the anion exchange structure 22 and the cation exchange structure 24. have. The spacer 23 may serve as a passage through which the fluid moves. An ion exchange resin may be filled in the spacer 23.

In addition, the heterogeneous ion exchange structures 22 and 24 may be connected to the respective electrodes 25 and 26. When a DC power is supplied to the electrodes 25 and 26, a potential difference is generated between the electrodes 25 and 26, and the ions present in the waste water by these potential differences are respectively separated from the ion exchange structures 22 and 24. Can be moved towards.

That is, the cation 23b may move to the cathode 26, and the anion 23a may move to the anode 25. For example, the cation 23b may be Na ⁺ , and the anion 23a may be Cl ⁻ .

Hereinafter, a method of manufacturing an ion exchange membrane and an ion exchange structure according to an embodiment of the present invention will be described with reference to FIG. 1 again.

First, a slurry is prepared by mixing ion exchange resin particles, a polymer binder, an additive, and a solvent. The ion exchange resin particles may be cation exchange resin particles or anion exchange resin particles.

Specifically, when the ion exchange resin particles are cation exchange resin, the cation exchange resin may be 30 to 60% by weight based on the weight sum of the cation exchange resin and the polymer binder. Preferably, the cation exchange resin may be 40 to 60% by weight based on the weight sum of the cation exchange resin and the polymer binder.

In addition, when the ion exchange resin particles are anion exchange resin, the anion exchange resin may be 10 to 40% by weight based on the weight sum of the anion exchange resin and the polymer binder. Preferably, the anion exchange resin may be 10 to 20% by weight based on the weight sum of the anion exchange resin and the polymer binder. The additive may be added at 0.05 times the weight sum of the ion exchange resin particles and the polymer binder, and the solvent may be added twice the weight sum of the ion exchange resin particles and the polymer binder.

For example, when the weight sum of the ion exchange resin and the polymer binder is 5g, the additive and the solvent may be 0.25g and 10g, respectively.

The ion exchange resin particles may be formed by pulverizing the ion exchange resin. The grinding may be performed using a ball mill. The ion exchange resins pulverized as described above are classified using a sieve to obtain ion exchange resin particles having a uniform size. The sieve may be a sieve enough to obtain fine particles of 100 μm or less.

The polymer binder may be a thermoplastic polymer. The thermoplastic polymer may be poly (vinyl butyral) (PVB). The PVB may maintain a liquid state even at a temperature below 100 ° C., thereby enabling film formation even at low temperatures.

The additive may include at least one or more of a dispersant, a hydrophobic polymer, and a plasticizer.

The dispersant may be poly ethyelene glycol (PEG).

The hydrophobic polymer may be polyvinyl chloride (PVC), polyethylene (PE), polypropylene (PP). When the ion exchange membranes are formed using the slurry containing the hydrophobic polymer, the water content of the ion exchange membranes can be lowered, thereby improving the mechanical strength of the ion exchange membranes. In this case, however, the ion exchange capacity may decrease and the electrical resistance may increase.

The plasticizer may be dioctyl phthalate (DOP). The plasticizer may control the elasticity and strength of the ion exchange membranes, and may facilitate molding and processing.

The solvent may be alcohol, toluene or water, and may be used by mixing them.

The slurry may be applied by tape casting to form the ion exchange membranes. The thickness of the ion exchange membranes 12 and 16 may be reduced by forming the ion exchange membranes 12 and 16 using the tape casting method. In addition, even when the ion exchange membranes 12 and 16 are implemented in a large area, they may be formed to have a uniform thickness. Specifically, an ion exchange membrane may be prepared by thinly applying the slurry onto a backing tape positioned on a tape caster and then removing the solvent.

The backing tape may be a stainless steel tape, an oil paper tape, a polymer tape. The polymer tape may be MYLAR, ACLAR tape. The backing tape may be coated with silicone to facilitate separation of the ion exchange membrane and the tape.

Ion exchange membranes may be formed in the same manner as described above, and the ion exchange structures may be formed by placing a fiber network between the ion exchange membranes and then bonding them. The bonding may use thermocompression bonding. At this time, the fiber network can improve the strength compared to the case where the ion exchange membrane is formed in a single.

The thermocompression may be performed by applying a pressure of 800 to 1000 kgf / cm ² at a temperature of 80 to 100 ℃, it may be carried out in a time of about 10 to 30 minutes so that the temperature and pressure is sufficiently applied to the ion exchange structure. Can be.

If the thermocompression bonding is performed at a temperature of 80 ° C. or less, no ion exchange resin is formed in the polymer binder structure, and thus, the ion exchange membrane is not formed. It can damage and damage the membrane.

In addition, when the pressure is applied at 800 kgf / cm ² or less, the ion exchange membranes and the fiber network may not be bonded, and when the pressure is applied at 1000 kgf / cm ² or more, the ion exchange structure may be damaged. The heterogeneous ion exchange structure prepared as described above may be cut to a constant size.

Through the thermocompression process as described above, the density and mechanical strength of the heterogeneous ion exchange structure can be improved, and the heterogeneous ion exchange structure can be flexible. In addition, by performing the thermocompression process, the thickness of the heterogeneous ion exchange structure can be uniformly formed, thereby enabling a large area.

The ion group at the end of the heterogeneous ion exchange structure prepared as described above is activated. The activation may be performed by immersing the ion exchange structure in an acid solution or a basic solution and maintaining the temperature at about 40 ° C. for 1 hour to 2 hours.

For example, in the case of a heterogeneous cation exchange membrane, activation of the ion group may be performed by dipping in HCl solution, and the heterogeneous anion exchange membrane may be performed by dipping in NaOH solution.

Hereinafter, preferred examples are provided to aid in understanding the present invention. However, the following experimental examples are only for helping understanding of the present invention, and the present invention is not limited to the following experimental examples.

Production Example  One: Heterogeneous  Preparation of Cation Exchange Structures (1)

Cation exchange resin particles were formed by grinding a cation exchange resin (Rhom and Hass, IR120). The pulverization was performed using a ball mill, and the pulverized cation exchange resin was classified using a sieve to obtain fine powder of 100 μm or less. The slurry was prepared by mixing the cation exchange resin particles, PVB as a polymer binder, PEG as a dispersant, dioctyl phthalate (DOP) as a plasticizer, and a mixed solvent of ethyl alcohol and toluene.

Specifically, the slurry was prepared by mixing the cation exchange resin particles and the polymer binder in a weight ratio of 30:70 to 5g, the dispersant and the plasticizer was 0.25g the sum of their weight. In addition, the solvent was prepared by mixing ethyl alcohol and toluene in a ratio of 1: 3 to 10g.

The slurry prepared as described above was applied to the base tape positioned in the tape caster thinly, and then a cation exchange membrane was prepared by removing the solvent. The thickness of the formed ion exchange film at this time was about 330 micrometers. The backing tape was a polymer tape coated with silicon.

The first cation exchange membrane and the second cation exchange membrane were prepared in the same manner as above, and a fiber network was disposed between the ion exchange membranes. The fiber network used a mesh of 100 mesh.

The first cation exchange membrane, the fibrous network and the second cation exchange membrane were joined by thermocompression bonding. The thermal compression was applied at a pressure of 800 to 1000 kgf / cm ² in the temperature range of 80 ℃ to 100 ℃, it was performed for about 30 minutes.

The width and length of the heterogeneous cation exchange structure thus prepared were cut into 18 cm and 35 cm, respectively, to prepare a cation exchange structure having a large area of 500 cm ² .

Production Example  2: Heterogeneous  Cation Exchange Structure Preparation (2)

Performed in the same manner as in Preparation Example 1, when preparing a slurry, the cation exchange resin particles and the polymer binder in a weight ratio of 40:60 to prepare a heterogeneous cation exchange structure.

Production Example  3: Heterogeneous  Preparation of Cation Exchange Structures (2006.01)

Performed in the same manner as in Preparation Example 1, when preparing a slurry, the cation exchange resin particles and the polymer binder in a weight ratio of 50:50 to prepare a heterogeneous cation exchange structure.

Production Example  4: Heterogeneous  Preparation of Cation Exchange Structures (4)

Performed in the same manner as in Preparation Example 1, when preparing a slurry, the cation exchange resin particles and the polymer binder in a weight ratio of 60:40 to prepare a heterogeneous cation exchange structure.

Production Example  5: Heterogeneous  Preparation of Anion Exchange Structure (1)

Performed in the same manner as in Preparation Example 1, an anion exchange resin (Rhom and Hass, IR120) was used in place of the cation exchange resin. In addition, in preparing the slurry, the anion exchange resin particles and the polymer binder were prepared in a weight ratio of 10:90 to prepare a heterogeneous anion exchange structure.

Production Example  6: Heterogeneous  Preparation of Anion Exchange Structure (2)

Performed in the same manner as in Preparation Example 5, in addition, in preparing the slurry, the anion exchange resin particles and the polymer binder were prepared at a weight ratio of 20:80 to prepare a heterogeneous anion exchange structure.

Production Example  7: Heterogeneous  Preparation of Anion Exchange Structure (3)

Performed in the same manner as in Preparation Example 5, in addition, in preparing the slurry, the anion exchange resin particles and the polymer binder were prepared in a non-homogeneous anion exchange structure in a weight ratio of 30:70.

Production Example  8: Heterogeneous  Preparation of Anion Exchange Structure (4)

Performed in the same manner as in Preparation Example 5, in addition, the anion exchange resin particles and the polymer binder in the preparation of the slurry to prepare a heterogeneous anion exchange structure in a weight ratio of 40:60.

Production Example  9: PVC Added Heterogeneous  Preparation of Cation Exchange Structures (1)

In the same manner as in Preparation Example 1, the cation exchange resin particles and the polymer binder was prepared in a weight ratio of 40: 60 to prepare a slurry of 5g, 0.25g of a hydrophobic polymer in a dispersant and a plasticizer having a total weight of 0.25g as an additive More was added. PVC was used as the hydrophobic polymer.

Production Example  10: PVC Added Heterogeneous  Cation Exchange Structure Preparation (2)

Performed in the same manner as in Preparation Example 9, 0.5g of the PVC hydrophobic polymer was added.

Production Example  11: PVC Added Heterogeneous  Preparation of Cation Exchange Structures (2006.01)

Performed in the same manner as in Preparation Example 9, 0.75g of the PVC hydrophobic polymer was added.

Production Example  12: PVC Added Heterogeneous  Preparation of Cation Exchange Structures (4)

Performed in the same manner as in Preparation Example 9, 1.0g of the PVC hydrophobic polymer was added.

Production Example  13: PE Added Heterogeneous  Preparation of Cation Exchange Structures (1)

In the same manner as in Preparation Example 1, the cation exchange resin particles and the polymer binder was prepared in a weight ratio of 40: 60 to prepare a slurry of 5g, 0.25g of a hydrophobic polymer in a dispersant and a plasticizer having a total weight of 0.25g as an additive More was added. PE was used as the hydrophobic polymer.

Production Example  14: PE Added Heterogeneous  Cation Exchange Structure Preparation (2)

Performed in the same manner as in Preparation Example 13, 0.5g of the PE hydrophobic polymer was added.

Production Example  15: PE Added Heterogeneous  Preparation of Cation Exchange Structures (2006.01)

Performed in the same manner as in Preparation Example 13, 0.75g of the PE hydrophobic polymer was added.

Production Example  16: PE Added Heterogeneous  Preparation of Cation Exchange Structures (4)

Performed in the same manner as in Preparation 13, 1.0g of the PE hydrophobic polymer was added.

Experimental Example  One: Heterogeneous  Cation Exchange membrane  Property evaluation

Tables 1 to 3 below show the physicochemical properties of Linan C (LinanEuro), CR 67 (Ionics) and MC 3470 (Sybron), which are heterogeneous cation exchange membranes compatible with the heterogeneous cation exchange structures according to Preparation Examples 1 to 4. The results of the measurement of electrochemical and mechanical properties are shown.

Hereinafter, physicochemical and electrochemical properties were evaluated as follows.

end. Thickness Measurement of Heterogeneous Ion Exchange Structures

The thickness of the heterogeneous ion exchange structure was a micrometer (Mitutoyo, Japan) that can measure up to 0.1 micron units. The average value was determined after measuring the thickness by repeating 3 to 5 times each.

I. Ion exchange capacity

Ion exchange capacity is the ion exchange functional groups are fixed to the structure (cation exchange structure: -RSO ₃ ^-, an anion exchange structure: -R ₄ N ⁺⁾ as an index representing the amount of was measured through a process as follows.

(1) The ion exchange structure to be measured is immersed in a high concentration of acid solution for 24 hours so that functional groups in the ion exchange structure are present as -SO ₃ H and -R ₄ N ⁺ . Here, the cation exchange structure was immersed in 1.0 N HCl solution, the anion exchange structure was immersed in 1.0 N NaOH solution.

(2) The acid solution remaining in equilibrium in the acid solution is washed with distilled water and soaked in distilled water for one day to remove the acid solution remaining on the membrane surface.

(3) The ion exchange structure is immersed in an acid solution again so that the cation and anion can be replaced in place of hydrogen ions. That is, the cation exchange structure was soaked in 0.5 mol / L NaCl so that the H ⁺ ion site was replaced with cation (Na ⁺ ) in the salt solution, and the anion exchange structure was soaked in 0.1 N HCl so that the H ⁺ ion site was anion It was allowed substituted with) an ion ^- OH.

(4) Measure the amount of ions substituted with the H ⁺ ions.

(5) Finally, the ion exchange structure is dried and weighed, and the ion exchange capacity is calculated by the following equation (1).

<Equation 1>

All. Water Swelling Ratio (WSR)

Each ion exchange structure was immersed in distilled water for 24 hours, the surface of the ion exchange structure was wiped well and weighed (wet weight W _wet ). Each ion exchange structure was placed in a vacuum oven and dried at 50 ° C. until a constant weight was measured and weighed (dry weight, W _dry ). Based on the results, the moisture content (WSR) was obtained by using Equation 2 below.

<Equation 2>

4. Electrical resistance

The electrical resistance of the ion exchange structure was performed in a 0.5 N NaCl solution, measured Z value and θ value using a LCZ meter (NF Electronics) in a clip cell manufactured in the laboratory, and the resistance (R) using Equation 3 below. ) Was obtained.

 In this case, since the resistance measured is a value obtained by combining the solution and each ion exchange structure, the resistance value of the ion exchange structure alone is measured by measuring the resistance of the solution itself using the same method as above and subtracting the resistance of the solution from the total resistance. Obtained.

In practice, the resistance of the film is important because the area resistance is multiplied by the area of the electrode used to express the electrical resistance value as the area resistance value (Ωcm ² ). The area of the electrodes used was 0.197 cm ² .

<Equation 3>

Area Resistance (Ω㎠) = ｜ Z ｜ × cosθ × Area

5. Ion Transport Number

The ion-exchange structures cut to size were immersed in 0.05 N NaCl solution for one day, and then mounted in two compartment cells filled with the same amount (150 mL) of 0.05 N NaCl solution and 0.01 N NaCl solution. By precisely measuring the potential on both sides of the ion exchange structure, the ion transport water was calculated using Equation 4 below.

<Equation 4>

Where C1 is 0.01 N, C2 is 0.05 N, E _m is the measured potential value, R is the ideal gas constant, T is the absolute temperature, and F is the Faraday constant.

Kinds Weight ratio of ion exchange resin and polymer binder Thickness (mm) Water content (%) Ion exchange capacity (meq / g) Transport Electrical resistance (Ω · ㎠) Preparation Example 1 30:70 0.33 60 1.7 0.88 6.83 Preparation Example 2 40:60 0.31 75 2.6 0.92 4.59 Production Example 3 50:50 0.37 81 2.8 0.91 4.23 Preparation Example 4 60:40 0.47 83 3.1 0.90 3.18 Linan c 0.42 67 2.5 0.91 6.7 CR 67 0.59 52 2.0 0.97 5.5

As can be seen from the results of Table 1, the heterogeneous cation exchange structures prepared in Preparation Examples 1 to 4 were reduced in thickness compared to commercially available heterogeneous ion exchange membranes, and in Preparation Examples 2 to 4, The water content was significantly improved.

Such water content shows hydrophilicity, and thus, it is judged that it has the ability to easily remove ions when applied to the ion exchange membrane process. Therefore, it is determined that the heterogeneous cation exchange structures prepared in Preparation Examples 2 to 4 of the present invention have a high ability to remove ions.

In addition, in ion transport water, for Preparation Examples 2 to 4, a value of about 0.9 was shown. This is almost equivalent to 0.91 of Linan C, a commercially available cation exchange structure.

In the case of electrical resistance, a value similar to that of commercially available heterogeneous ion exchange membranes was obtained, and among them, the electrical resistance of the cation exchange structures prepared in Preparation Examples 2 to 4 was low. It can be predicted that the cations can pass through the cation exchange structures due to the low electrical resistance, and this result can be matched with the ion exchange capacity value.

Judging from the results of measuring the physical and electrochemical properties, the cation exchange resin is preferably 30 to 60% by weight based on the weight sum of the cation exchange resin and the polymer binder, more preferably 40 to 60 It can be seen that the weight percent.

Table 2 below shows the results of evaluation of the mechanical properties of the heterogeneous cation exchange structures and the commercialized heterogeneous cation exchange membranes according to Preparation Examples 1 to 4.

Mechanical properties were evaluated at 10 mm / min using Instron 5567 from Universal Testing Machine, UK.

Kinds Weight ratio of ion exchange resin and polymer binder Stress (MPa) Tensile Rate (%) Modulus (MPa) Preparation Example 1 30:70 19.6 26.7 0.14 Preparation Example 2 40:60 15.8 26.5 0.12 Production Example 3 50:50 13.8 24.5 0.12 Preparation Example 4 60:40 10.6 19.4 0.10 Linanc 1.7 19.1 0.2 MC 3470 22.8 19.1 0.7

As can be seen from the results of Table 2, in the case of stress, the heterogeneous cation exchange structures according to Preparation Examples 1 to 4 exhibited higher values than commercialized heterogeneous cation exchange membranes, that is, LinanC, and were similar to those of MC 3470. The value is shown. Among the Preparation Examples 1 to 4, the stresses of Preparation Examples 1 to 3 showed higher values than those of Preparation Example 4.

In the case of the tensile rate, the heterogeneous cation exchange membrane according to the preparation of the present invention showed a higher value than the commercialized heterogeneous cation exchange membranes (MC3470 and LinanC). In Preparation Examples 1 to 4, the tensile modulus of Preparation Examples 1 to 3 was higher than that of Preparation Example 4.

In addition, when comparing the modulus value, the heterogeneous cation exchange structures prepared in Preparation Examples 1 to 4 of the present invention exhibited lower values than those of commercially available heterogeneous cation exchange membranes. Therefore, when comparing the stress and the tensile rate, it can be seen that the cation exchange structures prepared in Preparation Examples 1 to 4 of the present invention is excellent in mechanical strength. In the case of modulus values, when the numerical value is large, the hardness is improved, and when the numerical value is small, the ductility is improved. Therefore, it is determined that the cation exchange structures according to 1 to 4 in the preparation examples of the present invention have better ductility than commercially available heterogeneous cation exchange membranes.

In view of the mechanical property measurement results, the cation exchange resin is preferably 30 to 60% by weight based on the sum of the weight of the cation exchange resin and the polymer binder, but 30 to 50% by weight in consideration of stress and tensile rate. It can be seen that it is more preferable that it is%.

When referring to the physical and chemical properties, electrochemical properties and mechanical properties with reference to Table 1 to Table 2, most preferably the cation exchange resin 40 to 40 based on the weight sum of the cation exchange resin and the polymer binder 50 weight percent.

Experimental Example  2: Heterogeneous  Negative ion Exchange membrane  Property evaluation

Table 3 below shows the physicochemical properties and electrochemical properties of Linan C (LinanEuro), 204SZRA 67 (Ionics) and MC 3475 (Sybron), which are non-homogeneous anion exchange membranes compatible with Preparation Examples 5-8. Properties and mechanical properties were compared. Each characteristic evaluation was carried out using the same method as Experimental Example 1.

Kinds Weight ratio of ion exchange resin and polymer binder Thickness (mm) Water content (%) Ion exchange capacity (meq / g) Transport Electrical resistance (Ω · ㎠) Preparation Example 5 10:90 0.22 30 1.6 0.82 119.3 Preparation Example 6 20:80 0.24 37 2.0 0.86 13.8 Preparation Example 7 30:70 0.27 61 2.2 0.89 4.0 Preparation Example 8 40:60 0.33 78 2.5 0.81 3.3 Linan a 0.46 47 2.1 0.90 7.9 204SZRA 0.56 50 1.6 0.95 4.5

As can be seen from the results of Table 3, the heterogeneous anion exchange structures prepared in Preparation Examples 5 to 8 were reduced in thickness compared to commercially available heterogeneous ion exchange membranes. The water content was significantly improved.

Such water content shows hydrophilicity, and thus, it is judged that it has the ability to easily remove ions when applied to the ion exchange membrane process. Therefore, it is determined that the heterogeneous anion exchange structures prepared in Preparation Examples 7 to 8 of the present invention have a high ability to remove ions.

In ion transport water, Preparation Examples 5, 6, and 8 were slightly lower, but in Preparation Example 7, a value of 0.89 was derived, which was equivalent to that of commercially available anion exchange membranes.

In the case of electrical resistance, the heterogeneous ion exchange structure according to Preparation Example 5 had a high electrical resistance, and the amount of ion exchange was somewhat decreased. However, in Preparation Examples 7 to 8, the electrical resistance was low in the commercialized heterogeneous ion exchange membrane, thereby improving the ion exchange amount.

In view of the physical and electrochemical property measurement results, the anion exchange resin is preferably 10 to 40% by weight based on the weight sum of the anion exchange resin and the polymer binder, more preferably 30 to 40 It can be seen that the weight percent.

Table 4 shows the results of evaluation of the mechanical properties of the heterogeneous anion exchange structures and the commercialized heterogeneous anion exchange membranes according to Preparation Examples 5 to 8.

Kinds Weight ratio of ion exchange resin and polymer binder Stress (MPa) Tensile Rate (%) Modulus (MPa) Preparation Example 5 10:90 8.1 28.1 0.13 Preparation Example 6 20:80 7.3 27.6 0.11 Preparation Example 7 30:70 6.8 27.2 0.10 Preparation Example 8 40:60 5.6 25.4 0.07 Linana 1.0 8.5 0.11 MA 3475 10.4 18.3 0.63

As can be seen from the results of Table 4, in the case of stress, the heterogeneous anion exchange structures according to Preparation Examples 5 to 8 exhibited higher values than those of commercially available heterogeneous anion exchange membranes, that is, LinanC. The value is shown. Among the Preparation Examples 5 to 8, the stresses of Preparation Examples 5 to 7 showed higher values than those of Preparation Example 8.

In the case of the tensile rate, the heterogeneous anion exchange structure according to the preparation of the present invention showed a higher value than the commercialized heterogeneous anion exchange membranes (MC3470 and LinanC). In addition, among the Preparation Examples 5 to 8, the stresses of Preparation Examples 5 to 7 showed higher values than those of Preparation Example 8.

When comparing the modulus value, the heterogeneous anion exchange structures prepared in Preparation Examples 5 to 8 of the present invention showed lower values than the commercially available heterogeneous anion exchange membranes. Therefore, when comparing the stress and the tensile rate, it can be seen that the anion exchange structures prepared in Preparation Examples 5 to 8 of the present invention is excellent in mechanical strength. In the case of modulus values, when the numerical value is large, the hardness is improved, and when the numerical value is small, the ductility is improved. Therefore, it is determined that the anion exchange structures according to 5 to 8 in the preparation examples of the present invention have better ductility than commercially available heterogeneous anion exchange membranes.

In view of the mechanical property measurement results, the anion exchange resin is preferably 10 to 30% by weight based on the sum of the weight of the anion exchange resin and the polymer binder, but considering the stress and tensile rate 10 to 20% by weight It can be seen that it is more preferable that it is%.

Experimental Example  3: PVC Added Heterogeneous  Cation Exchange membrane  Property evaluation

Table 5 below shows the results of evaluating the physicochemical and electrochemical properties of the heterogeneous cation exchange structure according to Preparation Example 2 and the heterogeneous cation exchange structures added with PVC to Preparation Examples 9 to 12.

Kinds Thickness (mm) Weight ratio of ion exchange resin and polymer binder PVC (g) Water content (%) Ion exchange capacity (meq / g) Transport Electrical resistance (Ω㎠) Preparation Example 2 0.31 40:60 0 75 2.6 0.92 4.59 Preparation Example 9 0.31 0.25 70 3.1 0.91 4.83 Preparation Example 10 0.32 0.50 65 3.0 0.91 5.21 Preparation Example 11 0.40 0.75 65 2.9 0.89 5.52 Preparation Example 12 0.40 1.0 64 2.8 0.84 5.35

As can be seen from the results of Table 5, the heterogeneous cation exchange structures obtained in Preparation Examples 9 to 12 decreased the water content from 70% to 64% as the amount of PVC added increased. This is consistent with the above description that the water content will decrease if hydrophobic polymer is added to the heterogeneous ion exchange membrane as shown in FIG. 1. Therefore, it can be predicted that the water content decreases with the addition of PVC, so that the mechanical strength can be improved.

Based on the measurement results of the physicochemical and electrochemical properties, in the case of Preparation Examples 9 to 12, the cation exchange resin preferably has an amount of 0.25g to 1g of PVC, but considering ion exchange amount and transport water When it is found that it is more preferable that it is 0.25g to 0.5g.

Experimental Example  4: PE Added Heterogeneous  Cation Exchange membrane  Property evaluation

Table 6 below shows the results of evaluating the physicochemical and electrochemical properties of the heterogeneous cation exchange structure according to Preparation Example 2 and the heterogeneous cation exchange structures to which PE was added to Preparation Examples 13 to 16.

Kinds Thickness (mm) Weight ratio of ion exchange resin and polymer binder PE (g) Water content (%) Ion exchange capacity (meq / g) Transport Electrical resistance (Ω㎠) Preparation Example 2 0.31 40:60 0 75 2.6 0.92 4.59 Preparation Example 13 0.29 0.25 73 2.5 0.91 4.74 Preparation Example 14 0.33 0.50 72 2.3 0.91 4.91 Preparation Example 15 0.37 0.75 70 2.4 0.90 5.40 Preparation Example 16 0.38 1.0 65 2.2 0.90 5.83

As can be seen from the results of Table 6, the heterogeneous cation exchange structures obtained in Preparation Examples 13 to 16 decreased the water content from 73% to 65% as the amount of PE added increased. This is consistent with the above description that the water content will decrease if hydrophobic polymer is added to the heterogeneous ion exchange membrane as shown in FIG. 1. Therefore, it can be predicted that the water content decreases with the addition of PE, so that the mechanical strength can be improved.

Based on the measurement results of the physicochemical and electrochemical properties, in the case of Preparation Examples 13 to 16, the amount of cation exchange resin is preferably 0.25g to 1g, but considering the amount of ion exchange and transport water In this case, it can be seen that it is more preferable that it is 0.25g to 0.75g.

Experimental Example  5: Electric deionization  Process evaluation

The results of measuring the efficiency in the actual electrodeionization device of the heterogeneous cation exchange membranes compatible with the cation exchange structures of Preparation Examples 1 to 4 of the present invention. Each of the heterogeneous cation exchange structures and the commercialized heterogeneous cation exchange membranes prepared in Preparation Examples 1 to 4 of the present invention, and the spacer and the commercialized heterogeneous anion exchange membranes were alternately arranged to constitute a stack, and an electrodeionization thereof. Process evaluation was performed. As the commercialized heterogeneous anion exchange membrane, AMX (Astom) was used.

Evaluation of the efficiency of the electrodeionization process was carried out in a single cell (cell pair) of 40 cm 2 and the flow rate of the dilution chamber and the concentration chamber was 3 cm / min. In addition, in the deionization process, the influent was 0.05 M NaCl, the concentrate was 0.025 M NaCl, the electrode rinse solution (electrode rinse solution) 3% Na ₂ SO ₄ was used. The volume of each solution was used 500 mL, it was carried out for 7 to 8 hours at a current density of 1.5 mA / cm 2 applied at 50 ml / min conditions.

Kinds Ion exchange resins and polymer binders (% by weight) Current efficiency (%) NaCl flux (mol / ㎡hr) Energy consumption (kWh / mol) Preparation Example 1 30:70 77.3 1.81 0.27 Preparation Example 2 40:60 83.4 2.01 0.37 Production Example 3 50:50 86.3 2.05 0.36 Preparation Example 4 60:40 87.7 2.06 0.30 Linanc 85.9 1.99 0.30 MC3470 85.6 2.15 0.31

As can be seen from the results of Table 7, the efficiency of the electrodeionization process of the heterogeneous cation exchange structures and the commercialized heterogeneous cation exchange membranes prepared in Preparation Examples 1 to 4 of the present invention was NaCl flux, Preparation Example 4 And Linan C was 2.06 mol / m ² hr and 1.99 mol / m ² hr, respectively, resulting in higher values of Preparation Example 4 of the present invention.

In addition, as a result of comparing the current efficiency and the energy consumption required to move 1 mol of NaCl, the heterogeneous cation exchange structures prepared according to the preparation of the present invention yielded values similar to those of commercially available heterogeneous cation exchange membranes.

Therefore, in view of the result of measuring the electric deionization process, the cation exchange resin is preferably 30 to 60% by weight based on the weight sum of the cation exchange resin and the polymer binder, more preferably 40 to 60 It can be seen that the weight percent.

3A to 3B are graphs showing the efficiency in the electrodeionization apparatus according to the preparation example of the present invention. Specifically, Figure 3a is a graph showing the removal rate and power consumption of the cobalt ions, Figure 3b is a graph showing the power consumption, production water resistance and cobalt removal efficiency with time under the same conditions as Figure 3a.

Hereinafter, the stack was constructed using a cation exchange structure according to Preparation Example 2, a spacer and an anion exchange structure according to Preparation Example 7.

The electrodeionizer was performed in a single cell of 50 cm 2 and the flow rates of the dilution chamber and the concentration chamber were 6 cm / min, respectively. The influent was 10 ppm of Co (NO ₃ ) ₂ and the concentrate was set to 500 mW / cm Na ₂ SO ₄ . In addition, the electrode washing solution (electrode rinse solution) was used Na ₂ SO ₄ of 500 dl / cm. The applied current density was carried out at 1.5 mA / cm 2 for 6 hours.

Referring to FIG. 3A, when using heterogeneous ion exchange structures according to the preparation example of the present invention, the removal rate of cobalt ions was 98% or more. In addition, the power consumption corresponding to 1 L of produced water was about 0.2 Wh, which was very low.

3b shows that the time for removing cobalt ions can be removed in a short time of about 5 minutes, and the power consumption is in the range of 1.0 to 1.5 wh / L even after about 1 hour. It can be seen that it does not increase.

In addition, it can be seen that a very effective performance of about 12 MΩcm after 20 minutes of resistance operation of the production water.

Experimental Example  6: Electric deionization  Process evaluation

4A to 4B are graphs showing the results of an electrodeionization process evaluation of heterogeneous ion exchange structures. Specifically, FIG. 4A shows the electrical conductivity change of the heterogeneous ion exchange structures, and FIG. 4B shows the film resistance change of the heterogeneous ion exchange structures.

Hereinafter, the stack was prepared using a heterogeneous cation exchange constructs commercialized with a cation exchange construct according to Preparation Example 2 (Lanan C from LinanEuro, China, MC3470 from Sybron, USA), a spacer, and a commercialized heterogeneous anion exchange structure (AMX from Astom, Japan). Configured.

The electrodeionizer was performed in a single cell of 50 cm 2 and the flow rates of the dilution chamber and the concentration chamber were 3 cm / min, respectively. The influent was 0.05 M NaCl and the concentrate was 0.025 M NaCl. In addition, 3% Na ₂ SO ₄ was used as an electrode rinse solution. The applied current density was carried out at 1.5 mA / cm 2 for 6 hours.

Referring to FIG. 4A, the stack structure composed of the heterogeneous cation exchange structure according to Preparation Example 2 showed a change in electrical conductivity similar to that of each stack structure composed of commercially available heterogeneous cation exchange structures.

Referring to FIG. 4B, the stack structure of the heterogeneous cation exchange structure according to Preparation Example 2 showed a slightly higher film resistance value than the stack structure of MC3470, but showed a lower value than the stack structure of Linan C.

Although described above with reference to a preferred embodiment of the present invention, those skilled in the art will be variously modified and changed within the scope of the invention without departing from the spirit and scope of the invention described in the claims below I can understand that you can.

1 is a cross-sectional view showing a heterogeneous ion exchange structure according to an embodiment of the present invention.

Figure 2 is a schematic diagram showing an electric deionization device having a heterogeneous ion exchange structure according to an embodiment of the present invention.

3A to 3B are graphs showing the efficiency in the electrodeionization apparatus according to the preparation example of the present invention.

4A to 4B are graphs showing the results of an electrodeionization process evaluation of heterogeneous ion exchange structures.

<Description of the symbols for the main parts of the drawings>

12: first ion exchange membrane 14: fiber network

16: second ion exchange membrane 20: ion exchange structure

22: anion exchange structure 24: cation exchange structure

Claims (15)

Mixing an ion exchange resin, a polymer binder, an additive, and a solvent to form a slurry; Applying the slurry using a tape casting method to form an ion exchange membrane. The method of claim 1, The polymer binder is PVB manufacturing method of the ion exchange membrane. The method of claim 1, The additive is a method for producing an ion exchange membrane comprising at least one of a dispersant, a hydrophobic polymer or a plasticizer. The method of claim 1, The ion exchange resin is a cation exchange resin, The cation exchange resin is 30 to 60% by weight based on the sum of the weight of the cation exchange resin and the polymeric binder method of producing an ion exchange membrane. The method of claim 1, The ion exchange resin is an anion exchange resin, The anion exchange resin is a method of producing an ion exchange membrane of 10 to 40% by weight based on the weight sum of the anion exchange resin and the polymer binder. A first ion exchange membrane and a second ion exchange membrane formed by applying a slurry formed by mixing an ion exchange resin, a polymer binder, an additive, and a solvent by a tape casting method; And A heterogeneous ion exchange structure comprising a fiber network positioned between the first ion exchange membrane and the second ion exchange membrane. The method of claim 6, Wherein said polymeric binder is PVB. The method of claim 6, Wherein said additive comprises at least one of a dispersant, a hydrophobic polymer, or a plasticizer. Mixing an ion exchange resin, a polymer binder, an additive, and a solvent to form a slurry; Applying the slurry using a tape casting method to form a first ion exchange membrane and a second ion exchange membrane; And Positioning and bonding a fibrous network between the first ion exchange membrane and the second ion exchange membrane. The method of claim 9, The ion exchange resin is a cation exchange resin, The cation exchange resin is 30 to 60% by weight based on the sum of the weight of the cation exchange resin and the polymeric binder method of producing an ion exchange structure. The method of claim 9, The ion exchange resin is an anion exchange resin, The anion exchange resin is a method for producing an ion exchange structure of 10 to 40% by weight based on the weight sum of the anion exchange resin and the polymer binder. The method according to any one of claims 9 to 11, Wherein said polymeric binder is PVB. The method of claim 9, The additive is a method of producing an ion exchange structure is a dispersant, a hydrophobic polymer or a plasticizer. The method of claim 13, The hydrophobic polymer is a method of producing a heterogeneous ion exchange structure is PVC, PE or PP. The method of claim 9, The ion exchange membrane and the fibrous network is a method for producing a heterogeneous ion exchange structure, characterized in that the bonding using a thermal compression method.

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