KR101284009B1 - Manufacturing Method of Capacitive Deionization Electrode - Google Patents

Abstract

  The present invention is to control the structure of the polymer having an ion exchange group, the degree of amination to sulfonation or the concentration of the solution to directly coat the polymer on the carbon-based electrode to reduce the interface resistance between the ion exchange membrane and the electrode to reduce the resistance loss process Disclosed is a method for manufacturing an electrode for electrosorption ion removal, which maintains a conventional water treatment rate and reduces manufacturing costs due to a simplified process.

Description

 Manufacturing Method of Electrosorption Type Ion Removal Electrode {Manufacturing Method of Capacitive Deionization Electrode}

The present invention relates to a method for producing an electrode for electrosorption ion removal, and more particularly, to a method for manufacturing an electrode for electrosorption ion removal electrode directly coated with an ion exchange membrane, an electrode obtained therefrom, and a unit cell including the same.

Globally, drought phenomena due to global warming, groundwater depletion, desertification progress, population growth, and industrial and industrial water use are increasing, and as a resource of water is increasing, desalination of seawater and living and industrial wastewater Recycling is emerging as a new issue. In addition, as the interest in the production of industrial ultrapure water increases, and the demand for clear water to eat and wash in terms of life, research on the development of a high efficiency ion removal device is being actively conducted.

Currently, technologies for removing ions are mainly used by evaporation, reverse osmosis membrane method and ion exchange resin method. Evaporation and reverse osmosis membrane methods have high operating cost and operating problems due to high energy consumption. The exchange resin method has a disadvantage of making secondary pollutants because of excessive use of acid (Acid) or salt (NaCl) during regeneration.

In order to make up for the shortcomings of existing dissolved ion removal technologies and to develop new energy removal technologies with low energy consumption, researches are being conducted in various countries around the world. These new ion removal technologies are being developed in the US, LLNL and Sabrex of Texas. Capacitive deionization (CDI) technology.

CDI technology, which is an electrosorption type ion removal technology, consumes less energy than other methods. Unlike conventional ion removal technology, CDI technology does not require cleaning by chemicals, so it is an eco-friendly new ion removal technology without secondary pollution. Due to its simplicity, research is being actively conducted on next-generation dissolved ion removal technology. The first CDI process research was carried out in the 1960s by researchers at the University of Oklahoma, USA using a porous activated carbon electrode for desalination of seawater, and Johnson et al. Conducted a CDI experiment using activated carbon. However, due to the deterioration of the electrode, which is a key factor, it has not been developed due to the difficulty of continuous process. However, in the mid-'90s, the LLNL (Lawrence Livermore National Laboratory) developed a CDI process using a carbon aerogel electrode. In addition, research on the development of the CDI process using activated carbon fibers, carbon nanotubes, etc. as an electrode active material has also been conducted.

In the CDI process using only carbon-based electrodes, a problem arises in that the adsorption of ions from the adsorbed ions is desorbed to the opposite electrode as well as the ions are not desorbed from the electrode.

In order to compensate for this, there is a technique of inserting an ion exchange membrane between electrodes, and a schematic diagram of a unit cell employing the same may be illustrated in FIG. 1. However, in the case of the CDI process developed by placing the prepared ion exchange membrane on the electrode surface and using a method such as compression or heat fusion, a large interface resistance between the ion exchange membrane and the electrode surface acts to reduce the overall water treatment rate. In addition, there is still a need for additional process simplification to reduce manufacturing costs. In addition, the preparation of the ion exchange membrane involves a post-treatment process for preparing a polymer and then removing solvents or unreacted materials.

In one embodiment of the present invention to minimize the interfacial resistance between the carbon-based electrode and the ion exchange membrane as well as to provide a method of manufacturing an electrode for the electrosorption ion removal electrode that can reduce the manufacturing cost by simplifying the process in forming the ion exchange membrane. do.

In one embodiment of the present invention to provide an electrode for the electrosorption type ion removal that can minimize the interface resistance between the carbon material electrode and the ion exchange membrane.

In an embodiment of the present invention, the process of forming an ion exchange membrane separately and including the unit cell may be omitted, and the process may be simplified, and the interface resistance between the carbonaceous electrode and the ion exchange membrane may be minimized. The present invention provides a unit cell of an electroadsorption type ion apparatus having improved adsorption and desorption characteristics and ion removal rate efficiency.

In one embodiment of the present invention, a cationic conductor solution containing a polymer having a cation exchange group represented by the following Chemical Formula 1 or an anion conductor solution containing a polymer having an anion exchange group represented by the following Chemical Formula 2 is applied to a carbonaceous electrode and dried It provides a method for producing an electrode for electroadsorption ion removal comprising the step of forming an ion exchange membrane.

[Formula 1]

In Formula 1, A and A 'are the same as or different from each other, -S-, -SO _2- , -NH-, -C (CH ₃ ) ₂ -or -C = O-, and B is -O-,- SO _2- , -C = O- or -C (CF ₃ ) ₂ , X is sodium or potassium, n + m = k and n / (n + m) is 0.001 to 1.

[Formula 2]

In formula 2, Y is-, -CO-, -SO ₂ -or -O-, Z and D are the same or different from each other-, -O- or -S-, C is-, -C (CH ₃ ) ₂ -or -C (CF ₃ ) _2- , R ₁ is H or -CH ₂ N ⁺ R ₂ R ₃ R ₄ , R ₂ , R ₃ , R ₄ is the same or different from each other and is -CH ₃ , -CH ₂ CH ₃ ,-(CH ₂ ) ₂ CH ₃ , -CH ₂ NH ₂ ,-(CH ₂ ) ₂ NH ₂ or-(CH ₂ ) ₃ NH ₂ X and y are each arbitrary repeating unit, and x / (x + y) is 0.001-1.

In the manufacturing method of the electrode for the electrosorption ion removal ion according to an embodiment of the present invention, the polymer represented by the formula (1) is not dissolved in water to the intrinsic viscosity measured on NMP (N-methyl-α-pyrrolidinone) of 0.1 or more And, the intrinsic viscosity measured on the NMP can be used that exists in the range of 0.8 or more and 2.5 or less.

In the method for preparing an electrode for electrosorption ion removal according to a preferred embodiment of the present invention, the polymer represented by Formula 1 is n / (n + m) is 0.8 to 1, and the polymer represented by Formula 2 is x / ( x + y) may be used is 0.8 to 1.

In the manufacturing method of the electrode for the electrosorption ion removal ion according to a preferred embodiment of the present invention, the cation conductor solution may be used to include a polymer having a cation exchange group represented by the formula (1) in 10 to 30% by weight of the total solution , Anion conductor solution may be used to include a polymer having an anion exchange group represented by the formula (2) in 10 to 30% by weight of the total solution.

In the method for preparing an electrode for electrosorption ion removal according to a preferred embodiment of the present invention, the cation conductor solution is a polymerization product of a polymer having a cation exchange group represented by Formula 1, and the anion conductor solution is an anion represented by Formula 2. It may be a polymerization product itself of a polymer having an exchange group.

In the manufacturing method of the electrode for the ion adsorption type ion removal according to a preferred embodiment of the present invention, the ion exchange membrane may be formed to have a thickness of 10 to 20㎛.

In the manufacturing method of the electrode for the ion adsorption ion removal according to an embodiment of the present invention, the drying may be performed for 12 to 36 hours in the air or inert gas atmosphere of 55 to 65 ℃.

In another embodiment of the present invention; And an ion exchange membrane formed on the surface of the carbonaceous electrode and comprising a polymer including a cation exchange group represented by the following Chemical Formula 1 or a polymer including an anion exchange group represented by the following Chemical Formula 2; .

[Formula 1]

In Formula 1, A and A 'are the same as or different from each other, -S-, -SO _2- , -NH-, -C (CH ₃ ) ₂ -or -C = O-, and B is -O-,- SO _2- , -C = O- or -C (CF ₃ ) ₂ , X is sodium or potassium, n + m = k and n / (n + m) is 0.001 to 1.

[Formula 2]

In formula 2, Y is-, -CO-, -SO ₂ -or -O-, Z and D are the same or different from each other-, -O- or -S-, C is-, -C (CH ₃ ) ₂ -or -C (CF ₃ ) _2- , R ₁ is H or -CH ₂ N ⁺ R ₂ R ₃ R ₄ , R ₂ , R ₃ , R ₄ is the same or different from each other and is -CH ₃ , -CH ₂ CH ₃ ,-(CH ₂ ) ₂ CH ₃ , -CH ₂ NH ₂ ,-(CH ₂ ) ₂ NH ₂ or-(CH ₂ ) ₃ NH ₂ X and y are each arbitrary repeating unit, and x / (x + y) is 0.001-1.

In the electrosorption ion removal electrode according to a preferred embodiment of the present invention, the polymer represented by the formula (1) is insoluble in water with an intrinsic viscosity of 0.1 or more measured on NMP (N-methyl-α-pyrrolidinone), NMP Intrinsic viscosity measured in the phase may be present in the range of 0.8 or more and 2.5 or less.

In the electrode for electrosorption ion removal ion according to a preferred embodiment of the present invention, the polymer represented by Formula 1 is n / (n + m) is 0.8 to 1, the polymer represented by Formula 2 is x / (x + y ) May be from 0.8 to 1.

In the electrode for the electrosorption ion removal ion according to a preferred embodiment of the present invention, the ion exchange membrane may have a thickness of 10 to 20㎛.

Another embodiment of the present invention provides a unit cell of an electroadsorbing ion removing device including an electrode obtained according to the manufacturing method according to the above embodiments.

Another embodiment of the present invention provides a unit cell of an electroadsorption type ion removing device including the electrode according to the embodiments.

According to the present invention, it is possible to minimize the interface resistance between the carbon material electrode and the ion exchange membrane, and to reduce the manufacturing cost by simplifying the cost and simplifying the process in forming the ion exchange membrane, and separately forming the ion exchange membrane as a unit cell. Since the process can be omitted, the process can be simplified, and the interface resistance between the carbonaceous electrode and the ion exchange membrane can be minimized, thereby improving the adsorption and desorption characteristics and the ion removal efficiency of the ions. The water treatment efficiency of the removal process can be improved.

1 is a schematic diagram of the structure of an electroadsorption unit cell including a conventional ion exchange membrane.
FIG. 2 is a graph illustrating a result of evaluating ion removal rate over time by varying the type of electrode with respect to a unit cell using the electroadsorbing ion removing electrode obtained as an anode according to an embodiment of the present invention.
Figure 3 is a graph of the result of evaluating the water treatment rate according to the type of electrode for the unit cell using the electroadsorption type ion removal electrode obtained according to an embodiment of the present invention as a cathode.
Figure 4 is a graph of the results of comparing the adsorption and / or desorption characteristics of the ion adsorption and / or desorption characteristics with respect to the unit cell using the electrosorption type ion removal electrode obtained as an anode according to an embodiment of the present invention.
5 is a graph showing the result of evaluating the ion removal rate with time for the unit cell using the electroadsorption type ion removal electrode obtained as an anode according to one embodiment of the present invention.

The present invention relates to a method for producing an electrode for electrosorption ion removal, specifically to a method for producing an electrode for electrosorption ion removal having an ion exchange membrane by directly coating a polymer solution having an ion exchange group having a specific structural formula.

In one embodiment of the present invention, depending on whether the electrode is an anode or a cathode, the polymer solution having an ion exchange group may be a polymer having an anion exchange group or a polymer having a cation exchange group.

In one embodiment of the present invention, the polymer having a cation exchange group may be advantageous in terms of direct coating property on the carbonaceous electrode represented by the following Chemical Formula 1.

[Formula 1]

In Formula 1, A and A 'are the same as or different from each other, -S-, -SO _2- , -NH-, -C (CH ₃ ) ₂ -or -C = O-, and B is -O-,- SO _2- , -C = O- or -C (CF ₃ ) ₂ , X is sodium or potassium, n + m = k and n / (n + m) is 0.001 to 1.

Specifically, the polymer represented by Chemical Formula 1 is insoluble in water at least 0.1 having an intrinsic viscosity measured on NMP (N-methyl-α-pyrrolidinone). However, when applied as a cationic conductor, it is more preferable that the intrinsic viscosity measured on the NMP exists in the range of 0.8 or more and 2.5 or less. If the intrinsic viscosity is 0.1 or less, difficulty occurs in the post-treatment and film manufacturing process, and in order to coat the electrode directly, the value is preferably present in the range of 0.8 or more and 2.5 or less. Here, the viscosity of the final copolymer can be precisely controlled by adjusting the reaction environment, such as reaction temperature and reaction time, sulfonated monomer content.

The sulfonic acid group-containing polyarylene ether polymer compound represented by Chemical Formula 1 is obtained by a direct polymerization method between a sulfonated aromatic monomer, a monomer not containing a sulfonic acid group, and a bisphenol-based monomer, and the degree of sulfonation in the entire compound is sulfonated. It depends on the content of the monomers. C shown in Scheme 1 below means a leaving group that acts as a starting point of the reaction of each activated monomer, and has a form of halogenated elements such as F and Cl or -NO ₂ . The general reaction structure is shown in Scheme 1 below. Wherein A in the sulfonated monomer and A 'in the unsulfonated monomer have no obligation of identity, and are -S-, -SO _2- , -NH-, -C (CH ₃₎ capable of activating leaving group C ) ₂ --C = O- and the like freely selected. The B group in the bisphenol-based monomer structure is not particularly limited, but may be accompanied by a significant difference in reactivity depending on the steric structure of the compound to be selected. For reference, the compounds of each phenyl structure represented in Scheme 1 may be selected or combined from other types of aromatic alkyl groups such as naphthyl- groups.

[Reaction Scheme 1]

In Scheme 1, A, A ′, B, and X are as defined in Chemical Formula 1.

The sulfonated monomer in Scheme 1 was prepared through an aromatic nucleophilic substitution reaction of fuming sulfuric acid, thereby preparing a polymer in the form of sodium salt. The final product in Formula 1 and Scheme 1, cationic polymer, is referred to as SPAES-DD. Here, DD means the degree of sulfonation of the prepared cationic polymer, that is, n / (n + m) in the formula (1). If n / (n + m) is 1, the sulfonation degree may be represented as 100%. In one embodiment of the present invention, the sulfonation also affects the direct application of the polymer to the carbon electrode, the sulfonation degree of 0.1 to 100% (n / (n + m) ratio of 0.001 to 1) , Preferably 80% to 100% (0.8 to 1 in ratio of (n / (n + m)). Sulfonation is also a factor affecting water treatment.

The solution containing the polymer having a cation exchange group is preferably to apply the polymerization product itself obtained by polymerizing the polymer.

The concentration of the polymer having a cation exchange group in the solution containing the polymer having a cation exchange group may be controlled for coating property upon coating on the carbon electrode and ion exchange membrane formation into a thin film upon film formation, preferably in terms of thickness control. The polymer content with cation exchange capacity can be adjusted in the range of 10 to 30% by weight, preferably in the range of 10 to 25% by weight.

The method of coating the solution containing the polymer having such a cation exchange group on the carbon-based electrode can be carried out without particular limitation, but may be preferably coated using a method such as dip coating, spin coating, doctor blade. . After the coating may be carried out to dry or vacuum drying for 12 to 36 hours in an air or inert gas atmosphere of 55 to 65 ℃.

The ion exchange membrane obtained by applying a solution containing a polymer having a cation exchange group to the electrode and drying it may be formed into a thin film having a thickness of about 10 to 20㎛, even with such a thin film to form a separate ion exchange membrane or more It can be effective.

On the other hand, the polymer having an anion exchange group in one embodiment of the present invention may be advantageous in terms of direct coating on the carbon material electrode represented by the following formula (2).

[Formula 2]

In formula 2, Y is-, -CO-, -SO ₂ -or -O-, Z and D are the same or different from each other-, -O- or -S-, C is-, -C (CH ₃ ) ₂ -or -C (CF ₃ ) _2- , R ₁ is H or -CH ₂ N ⁺ R ₂ R ₃ R ₄ , R ₂ , R ₃ , R ₄ is the same or different from each other and is -CH ₃ , -CH ₂ CH ₃ ,-(CH ₂ ) ₂ CH ₃ , -CH ₂ NH ₂ ,-(CH ₂ ) ₂ NH ₂ or-(CH ₂ ) ₃ NH ₂ X and y are each arbitrary repeating unit, and x / (x + y) is 0.001-1.

In Formula 2, x / (x + y) is preferably 0.001 to 1, more preferably 0.8 to 1.0.

As an example of a method for producing a polymer having an anion exchange group represented by the formula (2) is a chloromethylated by reacting a solution in which a hydrocarbon-based polymer is dissolved with a chloromethylating agent in the presence of a catalyst (step 1), the chloromethylation obtained therefrom The dissolved hydrocarbon-based polymer is dissolved in a solvent and then reacted with an aminizing agent (step 2), but is not limited thereto.

[Reaction Scheme 2]

In Scheme 1, Y, Z, C, D, R ₁ , x and y are as defined in Formula 2, and n is x + y.

The solution containing the polymer having an anion exchange group is preferably to apply the polymerization product itself obtained by polymerizing the polymer.

The concentration of the polymer having an anion exchange group in the solution containing the polymer having an anion exchange group can be controlled for the coating property when coating on the carbon electrode and the formation of the ion exchange membrane into the thin film when forming the film, preferably in terms of thickness control The polymer content with anion exchange capacity can be adjusted in the range of 10 to 30% by weight, preferably 10 to 20% by weight, and most preferably in the range of 14 to 16% by weight.

The method of coating the solution containing the polymer having an anion exchange group on the carbon-based electrode can be carried out without particular limitation, but may be preferably coated using a method such as dip coating, spin coating, doctor blade. . After the coating may be carried out to dry or vacuum drying for 12 to 36 hours in an air or inert gas atmosphere of 55 to 65 ℃.

An ion exchange membrane obtained by applying a solution containing a polymer having an anion exchange group to an electrode and drying the same may be formed into a thin film having a thickness of about 10 to 20 μm, and such a thin film may be equivalent to or more than forming a separate ion exchange membrane. It can be effective.

In the above and the following description, the carbonaceous electrode may include an electrode made of carbon, a mixture of carbon and metal, a compound of carbon and metal, a mixture of carbon and a binder, or a mixture of carbon and a functional material, wherein carbon Of course, it may be included in the form of aerogels, activated carbon, graphite, nanotubes, fibers, powders and the like.

According to the electrode manufacturing method of the present invention, the solution containing the polymer represented by the formula (1) or the polymer represented by the formula (2) is coated on the carbon material electrode immediately after the filtration process and dried, the reaction solution is sedimented / separated separately It can be differentiated from the conventional method including the step of obtaining the aminated polymer through, and again to form it in the form of a membrane. Therefore, the manufacturing cost can be reduced by simplifying the process, and the interface resistance between the electrode and the ion exchange membrane can be reduced, thereby minimizing the resistance loss and increasing the water treatment rate. From these characteristics, the improvement of the performance of the electrode for electrosorption type ion removal apparatus of this invention, and the electrosorption type ion removal apparatus provided with the same can be expected.

Hereinafter, the present invention will be described in more detail with reference to Examples, but the present invention is not limited to the following Examples.

Example 1 Preparation of Electrode and Unit Cell Coated with Polymer Having Cation Exchange Group

(1) Preparation of sulfonated polyarylether sulfone (SPAES-DD)

In a 100 ml branched round flask, a gas inlet, thermometer, dean stark trap, condenser and mechanical stirrer were installed and nitrogen was used to remove air and other impurities for a few minutes. g DCDPS (4,4'-dichlorodiphenylsulfone; 1.5 mol), 7.1019 g BP (4,4'-biphenol; 2 mol), 4.6840 g SDCDPS (3,3'-disulfonated-4,4'-dichloro- diphenylsulfone 0.5 mol), 6.0618 g K ₂ CO ₃ (1.15 mol), 44.4 g NMP, 22.2 ml toluene (NMP / toluene = 2/1, V / V) were added and stirred at 80 ° C. or higher for 1 hour. The monomer was dissolved. Thereafter, the temperature of the reaction solution was raised to 160 ° C., and the reaction product was refluxed with toluene for 4 hours to remove water, and then heated up to 190 ° C. to completely remove residual toluene from the Dean-Stark trap and react for 24 hours. After the reaction was completed, the reaction mixture was cooled to room temperature, thereby preparing a cationic polymer having a sulfonation degree of 25%. Table 1 below shows the characteristics of sulfonated polyarylether sulfones having different degrees of sulfonation.

The numbers written in SPAES in Table 1 below indicate the degree of sulfonation of sulfonated polyarylether sulfones.

Intrinsic viscosity (IV) in Table 1 is the intrinsic viscosity measured on a room temperature (25 ℃) NMP.

(2) Preparation of Electrosorption Type Ion Removal Electrode Coated with Sulfonated Polyarylether Sulfone (SPAES-DD)

The SPAES-30 cationic polymer prepared above was coated directly with a doctor blade on the carbonaceous electrode at a concentration of 10 to 30 wt% to have a thickness of 10 to 20 μm, and then 36 hours at 55 ° C. After drying under reduced pressure, an electrode for ion adsorption ion removal coated with a cation exchange membrane was prepared. If the thickness of the coating layer prepared above is less than 10㎛ does not remove ions and water purification treatment, if the coating is more than 20㎛ 10 because the interface resistance of the membrane is rapidly increased and unnecessary ion conductor is consumed because it is not suitable 10 Preference is given to ˜20 μm.

(3) Electrosorption type ion removal experiment using sulfonated polyarylether sulfone (SPAES-DD) coated electrode

After using the electrode coated with the sulfonated polyarylether sulfone obtained from the above (2) as a negative electrode and using a commercially available anion exchange membrane not coated as a positive electrode, The prepared electrode was cut into 10 × 10 cm 2, and 100 μm-thick spacers (200 mesh, polyamide) were installed to prevent short-circuits due to contact between the anode and the cathode and to serve as a flow path for the flow of fluid. A hole having a radius of 1 cm was prepared to allow the solution to pass through the spacer on the four sides of the electrode and to exit to the center. A 15 × 15 cm 2 acrylic plate was fixed to the outside of the positive electrode and the negative electrode to form a single cell for electrosorption ion removal.

The adsorption and desorption characteristics of the salt and the removal rate of the salt according to the type of the negative electrode were investigated using the prepared single cell for the ion adsorption ion removal. In operation, a 200 ppm NaCl solution was supplied at a rate of 30 mL / min, a voltage of 1.5 V was applied to the electrode, followed by 3 minutes of adsorption and 2 minutes of desorption. Adsorption and desorption characteristics of ions over time of the manufactured cell are shown in FIG. 2.

And the ion removal rate was measured to measure the water treatment rate is shown in FIG.

In Figures 2 and 3 SP-4 is an embodiment of the present invention applying a negative electrode coated with a sulfonated polyarylether sulfone represented by the formula (1) having a sulfonation degree of 25%, SP-1 is a sulfonation degree of 50 %, SP-3 is 35% sulfonated and SP-2 is 30% sulfonated.

As shown in FIG. 2, the adsorption and desorption characteristics of the electrosorption ion removal in the unit cell for the electrosorption ion removal using the electrode prepared by coating a specific polymer having a cation exchange group on the electrode according to the embodiment of the present invention are various. When the cationic conductor having a sulfonation degree is applied, it can be seen that the desorption of ions is excellent, and as shown in FIG. 3, it shows an excellent water treatment ratio of 75% to 92%. Therefore, when applying the ion-conductor for water treatment prepared above will show excellent performance even in the alternative application of the commercialized cation exchange membrane.

Example 2 Preparation of Electrode and Unit Cell Coated with Polymer Having Anion Exchanger

(1) Preparation of Anion Conductor-Containing Solution

100 g of polysulfone (UDEL ^ㄾ Polysulfone, P-3500 LCD MB, Solvay Advanced Polymers) was dried in a vacuum oven at 100 ° C for 24 hours, and the dried polysulfone was equipped with a mechanical stirrer, gas inlet, condenser and temperature bath for temperature setting. Into a 1 L four-necked round bottom flask installed. Subsequently, the solution was prepared by sufficiently dissolving polysulfone to 12.8 wt% with respect to 425.8 ml of 1,1,2,2-tetrachloroethane (TCE). After complete dissolution at room temperature, the temperature of the constant temperature water bath was set to 40 ° C. 8.7327 g of catalyst ZnCl ₂ was added to the reactor, followed by stirring for about 30 minutes. Thereafter, 103.0 ml of chloromethyl methyl ether (CMME) is dropped through a dropping funnel, and the amount of CMME added is 6 times (6 × (poly) of the number of moles of CMME reacted per mole of polysulfone repeat unit. Calculated as the amount of sulfone (g) / repeated unit molecular weight (g / mol) × chloromethyl methyl ether molecular weight (g / mol)} and dripped vigorously while injecting dry inert gas through the gas inlet attached to the reactor. The reaction mixture was filtered and precipitated in excess methanol, and the precipitated chloromethylated polysulfone was ground with a grinder and washed several times with methanol and third distilled water. Methylated polysulfone was dried in a drier at 80 ° C. for 12 hours and vacuum dried at 80 ° C. The chloromethylation reaction is shown in Scheme 3 below.

Scheme 3

(In the above, x, y and R ₁ are as defined above, n is any repeating unit, and x + y = n.)

In the reaction, the degree of chloromethylation (x / n) can be analyzed by ¹ H NMR (nuclear magnetic resonance) spectroscopy and the degree of chloromethylation of polysulfone in this example was 0.95.

200 g of the prepared chloromethylated polysulfone was placed in a 2 L four-necked round bottom flask equipped with a mechanical stirrer and sufficiently dissolved in 1489.4 ml of dimethylacetamide (DMAc, N, N-dimethylacetamid) to 12.5 wt%. Dropping 366.0 ml of trimethylamine aqueous solution using a dropping funnel to the reactor, wherein the amount of the trimethylamine aqueous solution added was 4 times (4 × (chloro) of the number of moles of trimethylamine per mole of repeating units of chloromethylated polysulfone. Methylated polysulfone amount (g) / repeated unit molecular weight (g / mol) × trimethylamine molecular weight (g / mol)} was added dropwise, followed by vigorous stirring at room temperature for 12 hours, followed by filtration and anion conductor. The containing solution was obtained, The amination reaction of the said chloromethylated polysulfone is shown by following Reaction Formula 4 .

[Reaction Scheme 4]

(In the above, x, y, R ₁ and R ₁ ′ are as defined above and x + y = n.)

(2) Preparation of Electrode for Electrosorption Type Ion Removal Device

After coating the anion conductor-containing solution containing a hydrocarbon-based polymer having anion-exchange capacity prepared in (1) on the carbon material electrode to the thickness of the coating layer on one side of the electrode by using the doctor blade method 10 to 20㎛ After drying at 55 ° C. for 12 hours, and drying under reduced pressure at 55 ° C. for 36 hours, an electrode for an electroadsorption type ion removal device was formed by coating an anion exchange membrane on a carbon material electrode.

(3) Single cell production using an electrode coated with anion exchange membrane

An electrode was prepared using an electroadsorption type ion removal electrode having an anion exchange membrane coated thereon on the carbonaceous electrode prepared in (2) as an anode, and a commercial cation exchange membrane uncoated as a cathode. After cutting each electrode to 10 × 10㎠, 100 μm thick spacers (200 mesh, polyamide) are mounted to prevent short-circuit by contact between the positive electrode and the negative electrode, and serve as a passage through which fluid can flow. Provided. A hole with a radius of 1 cm was drilled in the center of the electrode to prepare a solution to pass through the spacers from the four sides of the electrode to the center. A 15 × 15 cm 2 acrylic plate was fixed to the outer side of the positive electrode and the negative electrode to form a single cell for electrosorption ion removal.

The adsorption and / or desorption characteristics and the ion removal rate of the salt according to the type of the positive electrode were measured using the electrosorption ion removal single cell prepared in (3). In operation, a 200 ppm NaCl solution was supplied at a rate of 30 mL / min, a voltage of 1.5 V was applied to the electrode, and a 3 minute adsorption and a 2 minute desorption process were performed.

On the other hand, Comparative Examples 1 to 3 were formed by stacking a commercially available anion exchange membrane on a carbon-based electrode (anode) to configure each unit cell, and then measured adsorption and / or desorption characteristics and ion removal rate of ions under the same conditions. will be.

Specifically, Comparative Example 1 is commercialized fumasep ^?? Is a anion exchange membrane and a unit cell is constructed. Comparative Example 2 is a unit cell composed of PCA-based PC-SK as an anion exchange membrane, and Comparative Example 3 is a unit cell formed using Tokuyama Soda Neosepta AMX as an anion exchange membrane. It is made up.

4 shows the adsorption and / or desorption characteristics of ions over time with respect to the unit cell including the electrode for the electrosorption type ion removal device of the present invention, and FIG. 5 shows the ion removal rate.

From the results of FIGS. 4 to 5, the case of employing an electrode having a polymer coating layer having an anion exchange group represented by the formula (2) according to an embodiment of the present invention is used rather than having a conventionally available anion exchange membrane. Adsorption and desorption properties of and the result can be confirmed that the ion removal rate is improved.

As described above, the present invention, in the unit cell of the electroadsorption ion removal device, by coating a hydrocarbon-based polymer-containing solution having a liquid anion exchange capacity on the surface of the carbon material electrode, the anion exchange membrane directly on the carbon material electrode By providing a unit cell of the electroadsorption type ion removal device to minimize the interface resistance between the carbon material electrode and the anion exchange membrane. Accordingly, the present invention can reduce the interface resistance between the carbon material electrode and the anion exchange membrane to reduce the resistance loss and simplify the process, thereby increasing the water treatment rate, as well as reducing the manufacturing cost due to the process simplification.

In addition, the adsorption-desorption characteristics and ion removal rate efficiency of ions to the unit cell of the electroadsorption ion removal device of the present invention was improved. The present invention provides a method for producing an electrode for an electroadsorption type ion removal device which can omit the conventional film forming step of the ion exchange membrane by directly forming an ion exchange membrane on the carbonaceous electrode by coating. In addition, the present invention provides a method for producing a hydrocarbon-based polymer having a novel anion exchange capacity.

Although the present invention has been described in detail only with respect to the embodiments described, it will be apparent to those skilled in the art that various modifications and changes are possible within the technical scope of the present invention, and such modifications and modifications belong to the appended claims.

Claims (13)

Next, a cation conductor solution containing a polymer having a cation exchange group represented by Formula 1 or an anion conductor solution containing a polymer having an anion exchange group represented by Formula 2 is coated on a carbonaceous electrode and dried to have a thickness of 10 to 20 μm. A method for producing an electroadsorption ion removal electrode for water treatment, comprising the step of forming an ion exchange membrane.
[Formula 1]

In Formula 1, A and A 'are the same as or different from each other, -S-, -SO _2- , -NH-, -C (CH ₃ ) ₂ -or -C = O-, and B is -O-,- SO _2- , -C = O- or -C (CF ₃ ) ₂ , X is sodium or potassium, n + m = k and n / (n + m) is 0.25 to 0.5.
(2)

In formula 2, Y is-, -CO-, -SO ₂ -or -O-, Z and D are the same or different from each other-, -O- or -S-, C is-, -C (CH ₃ ) ₂ -or -C (CF ₃ ) _2- , R ₁ is H or -CH ₂ N ⁺ R ₂ R ₃ R ₄ , R ₂ , R ₃ , R ₄ is the same or different from each other and is -CH ₃ , -CH ₂ CH ₃ ,-(CH ₂ ) ₂ CH ₃ , -CH ₂ NH ₂ ,-(CH ₂ ) ₂ NH ₂ or-(CH ₂ ) ₃ NH ₂ X and y are each arbitrary repeating unit, and x / (x + y) is 0.001-1. The method of claim 1,
The polymer represented by Chemical Formula 1 is insoluble in water having an intrinsic viscosity measured on NMP (N-methyl-α-pyrrolidinone) of 0.1 or more, and the intrinsic viscosity measured on NMP is in a range of 0.8 or more and 2.5 or less. Method for producing an electrosorption ion removal electrode for water treatment. The method of claim 1,
The polymer represented by the formula (2) is x / (x + y) is 0.8 to 1 method of producing an electroadsorption type ion removal electrode for water treatment. The method of claim 1,
The cation conductor solution comprises 10 to 30% by weight of the polymer having a cation exchange group represented by the formula (1) in the total solution, the anion conductor solution is 10 to 30% by weight of the polymer having an anion exchange group represented by the formula (2) Method for producing an electroadsorption type ion removal electrode for water treatment comprising a%. The method of claim 1,
The cation conductor solution is a polymerization product itself of the polymer having a cation exchange group represented by the formula (1), the anion conductor solution is a polymerization product itself of the polymer having an anion exchange group represented by the formula (2) of the electrosorption type ion removal electrode for water treatment Way. delete The method of claim 1,
Drying is a method for producing an electroadsorption deionization electrode for water treatment is carried out for 12 to 36 hours in the air or inert gas atmosphere of 55 to 65 ℃. Carbon material electrode; And
Water treatment electric including an ion exchange membrane having a thickness of 10 to 20㎛ formed on the surface of the carbon-based electrode, a polymer comprising a cation exchange group represented by the following formula (1) or a polymer containing an anion exchange group represented by the following formula (2) Adsorption deionization electrode.
[Formula 1]

In Formula 1, A and A 'are the same as or different from each other, -S-, -SO _2- , -NH-, -C (CH ₃ ) ₂ -or -C = O-, and B is -O-,- SO _2- , -C = O- or -C (CF ₃ ) ₂ , X is sodium or potassium, n + m = k and n / (n + m) is 0.25 to 0.5.
(2)

In formula 2, Y is-, -CO-, -SO ₂ -or -O-, Z and D are the same or different from each other-, -O- or -S-, C is-, -C (CH ₃ ) ₂ -or -C (CF ₃ ) _2- , R ₁ is H or -CH ₂ N ⁺ R ₂ R ₃ R ₄ , R ₂ , R ₃ , R ₄ is the same or different from each other and is -CH ₃ , -CH ₂ CH ₃ ,-(CH ₂ ) ₂ CH ₃ , -CH ₂ NH ₂ ,-(CH ₂ ) ₂ NH ₂ or-(CH ₂ ) ₃ NH ₂ X and y are each arbitrary repeating unit, and x / (x + y) is 0.001-1. The method of claim 8,
The polymer represented by Chemical Formula 1 is insoluble in water having an intrinsic viscosity measured on NMP (N-methyl-α-pyrrolidinone) of 0.1 or more, and the intrinsic viscosity measured on NMP is in a range of 0.8 or more and 2.5 or less. Electrodesorption deionization electrode for water treatment. The method of claim 8,
The polymer represented by the formula (2) is x / (x + y) is 0.8 to 1, the electrosorption type ion removal electrode for water treatment. delete A unit cell of an electrosorption type ion removal device for water treatment, comprising an electrode obtained according to any one of claims 1 to 5 and 7. A unit cell of an electroadsorption type ion removal device for water treatment, comprising the electrode of any one of claims 8 to 10.

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