KR101284557B1 - Carbon Composite for Capacitive Deionization Electrode and Its Manufacturing Method Thereof - Google Patents

Abstract

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a carbon composite for a capacitive desalination electrode and a method of manufacturing the same, and more particularly, to the role of an electrode by integrating an electrode and a current supply plate which are components of a stack of a capacitive deionization (CDI) system having ion selectivity. A carbon composite that can simultaneously perform the adsorption / desorption ability of phosphorus ions and the ability to supply current to an electrode, which serves as a current supply plate, and increases the adsorption capacity of electrodes by stacking active electrode materials on carbon paper as a support. It has excellent absorption and desorption ability of ions in the process, carbon composite is flexible, and has the effect of performing the role of electrode and current supply plate through electrochemical analysis, while reducing stack volume and manufacturing method simple It relates to a carbon composite for a capacitive desalination electrode and a method for manufacturing the same that can reduce the cost.

Description

Carbon Composite for Capacitive Deionization Electrode and Its Manufacturing Method Thereof}

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a carbon composite for a capacitive desalination electrode and a method of manufacturing the same, and more particularly, to the role of an electrode by integrating an electrode and a current supply plate which are components of a stack of a capacitive deionization (CDI) system having ion selectivity. A carbon composite that can simultaneously perform the adsorption / desorption ability of phosphorus ions and the ability to supply current to an electrode, which serves as a current supply plate, and increases the adsorption capacity of electrodes by stacking active electrode materials on carbon paper as a support It has excellent absorption and desorption ability of ions in the process, carbon composite is flexible, and has the effect of performing the role of electrode and current supply plate through electrochemical analysis, while reducing stack volume and manufacturing method simple It relates to a carbon composite for a capacitive desalination electrode and a method for manufacturing the same that can reduce the cost.

As living water or industrial water, water is very important in human life. However, in modern times, water contains heavy metals, nitrate nitrogen, and fluoride ions, and when people drink water containing such substances for a long time, they can be very harmful to health. Thus, numerous water treatment techniques have been developed, such as reverse osmosis (RO), electrodialysis (ED), and ion exchange (EDI) methods, but these techniques must meet high cost and high risk technical conditions. For example, reverse osmosis systems require high pressures and pretreatment processes and also cause high volume of concentrated water. Therefore, even with high efficiency thin film technology, a very dangerous and expensive process is required for its operation. In the case of electrodialysis, a high pressure is required because of the high pressure, and the production process is complicated by causing membrane fouling from hardness ions and organic materials. The ion exchange method using an ion exchange resin has a disadvantage of causing secondary pollution and removing total dissolved solids (TDS) due to various chemicals.

Accordingly, a capacitive deionization (CDI) system using a water purification technique using an electro-absorption and electric double charge principle has been developed in order to overcome the above disadvantages. The stack of the CDI is composed of a support plate, a current supply plate, an electrode, a gasket, and an electrode separator. The current supply plate receives the current from the power supply and makes a positive electrode or negative electrode on the electrode attached to the current supply plate, and the negative ions and the positive ions are attracted to the respective electrodes according to the electrical attraction.

The current supply plate of the conventional capacitive desalination electrode stack uses a lot of graphite material, and the electrode uses a porous carbon material such as carbon cloth, carbon nanotube, and carbon aerogel. As described above, although the current supply plate and the electrode may be made of a similar material, they are separately configured, thereby increasing the manufacturing cost and inconvenient in assembling the CDI stack.

In recent years, CDI has been used in the catalytic domain, computer hardware production, premedical diagnostics, biological sensors, hydrogen storage, and impurity purification processes (e.g., nonionic surfactants, benzene, aniline, bipyridyl and inorganic mixtures). It is applied to the same various fields.

Hard water, such as the number of boilers containing hard material, can cause scale in boilers or heat exchangers, which can significantly reduce the efficiency of the process.In the electronics and pharmaceutical industries, ultrapure water that has completely removed ionic substances is an important factor in determining product performance. Acts as. In addition to the above fields, the next generation of CDI will need CDI applied to portable drinking water and quick water. Such CDI will require a CDI that is minimized by making the size as small as possible.

Therefore, there is a need for the development of a CDI having a minimum volume while maintaining the effect of the CDI while maintaining a simple and safe manufacturing process and a costly process.

The first problem to be solved by the present invention is to provide a method for producing a carbon composite for capacitive desalination electrode comprising activated carbon and a support.

The second object of the present invention is to provide a carbon composite for capacitive desalination electrode comprising activated carbon and a support.

The third object of the present invention is to provide a capacitive desalination stack comprising a carbon composite including activated carbon and a support.

The fourth problem to be solved by the present invention is to confirm the applicability by confirming the capacity of the capacitive desalination electrode by producing a carbon composite and applying it to CDI.

The fifth problem to be solved by the present invention is to confirm the applicability by verifying the capacity of the capacitive desalination current supply plate by applying the carbon composite and the same to the CDI.

The sixth problem to be solved by the present invention is that the carbon composite in the present invention should perform both the role of the current supply plate and the electrode, the ions in the aqueous solution is capable of adsorption and desorption on the surface of the carbon composite, the electrical conductivity flowing current It is to provide a capacitor having.

The present invention to solve the first technical problem,
(1) adding a binder to a solvent to prepare a mixture;
(2) preparing an slurry by adding an electrode active material to the mixture;

(3) casting the electrode active material slurry obtained in the step (2) to the end face of the network structure, or dipping the support into the electrode active material slurry to deposit the electrode active material on the support of the network structure and then dry the carbon composite It is to provide a method for producing a carbon composite for a capacitive desalination electrode characterized in that the electrode active material is deposited on the support of the network structure so as to be integrated.

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In addition, the present invention to solve the second technical problem,

It is to provide a carbon composite for a capacitive desalination electrode, characterized in that the electrode active material and the support are integrated.

In another aspect, the present invention, in order to solve the third technical problem, the carbon composite prepared according to the production method, the capacitance is 23 F / g or more, the electrical conductivity is 0.401 S / ㎝ or more, desalination is characterized in that more than 70% It provides a carbon composite that can sufficiently perform the role of the electrode and the current supply plate.

In addition, the present invention is characterized in that it can be applied to a capacitor including a stack of CDI made of a carbon composite prepared according to the manufacturing method in order to solve the fourth technical problem.

Hereinafter, the term described in this specification is demonstrated.

The term “Electric double layer (EDL)” means that when a metal is immersed in an electrolyte, the charge ions stick to the metal because the metal has a charge force. For example, negative charges collect in the metal and positively charged ions cling to the metal surface in the electrolyte. The cling ions form a charge layer like a capacitor. Such a phenomenon is called an electric double layer.

According to the carbon composite according to the present invention and a method for producing the same, the method for producing the carbon composite is simple, safe, and does not require a costly process, while maintaining the effects of CDI as it is, CDI by including an integral carbon composite in the CDI stack While the components in the stack are reduced, and the cost of electrodes and current supply plates in the CDI stack is very high, the carbon composite material is inexpensive, reducing the manufacturing cost and simplifying the CDI stack assembly during capacity expansion of the CDI stack. Have

In addition, the carbon composite according to the present invention is to perform both the role of the current supply plate and the electrode, so that the ions in the aqueous solution is a capacitor capable of adsorption and desorption on the surface of the carbon composite and has the effect of flowing electrical current.

In addition, the carbon composite according to the present invention used porous carbon having a wide surface area to allow adsorption and desorption in order to maximize the contact surface between the surface and the ions in the aqueous solution. Has the effect of making it.

1 is a diagram illustrating components of a stack of a general CDI.
2 is a diagram illustrating components of a stack of a CDI according to the present invention.
3 is taken using video microscopy, the upper left picture of Figure 3 is a magnified view of the surface of the carbon paper before casting the activated carbon slurry 100 times, the upper right picture of Figure 3 is carried out The carbon composite of Example 1 is shown enlarged by 100 times, the lower left picture of Figure 3 shows an enlarged 300 times the surface of the carbon paper before casting the activated carbon slurry, the lower right picture of Figure 3 is the carbon of Example 1 The complex is shown magnified 300 times.
FIG. 4 is a scanning electron microscope (SEM) image of the carbon composites of 200 μm, 5 μm, and 1 μm of Example 1, showing the surface taken at magnification.
5 is a graph showing the results of measuring capacitances of Comparative Example 1, Example 1, and Comparative Example 2. FIG.
FIG. 6 is a graph showing the results of measuring the electrical conductivity of carbon treated without any treatment, Comparative Example 1, Example 1 and Comparative Example 2.
7 is a graph showing the change in ion conductivity according to desalination by the concentration of NaCl in Example 1.

According to the present invention, a CDI stack can be excluded from an expensive electrode and a current supply plate by applying a carbon composite integrated with a single element in place of the current supply plate and the electrode constituting the existing CDI stack to the CDI stack. The cost was reduced, the assembly process was simplified, and their outstanding electrochemical properties were identified.

Method for producing a carbon composite for a desalination electrode according to the present invention,
(1) adding a binder to a solvent to prepare a mixture;
(2) preparing an slurry by adding an electrode active material to the mixture;
(3) casting the electrode active material slurry obtained in the step (2) to the end face of the network structure, or dipping the support into the electrode active material slurry to deposit the electrode active material on the support of the network structure and then dry the carbon composite Obtaining Step

Since the electrode active material is deposited on the support of the network structure is characterized in that the integrated.

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In the method of manufacturing a carbon composite according to the present invention, in the step (1), the binder is used to fix the position of the electrode active material, poly (vinylidene fluoride) (poly PVdF) and poly One or more selected from the group consisting of tetrafluoroethylene (PTFE) and the like may be used, but is not limited thereto.

The solvent is not particularly limited in kind, and for example, one kind selected from the group consisting of N-methyl-2-pyrrolidone (NMP), dimethylacetamide (DMAc), dimethylformamide (DMF), and the like. Although the above can be used, it is not limited to this.

The content of the solvent is preferably 1,000 to 2,000 parts by weight with respect to 100 parts by weight of the binder, but less than 1,000 parts by weight is not preferable because the binder is not completely dissolved, and if it exceeds 2,000 parts by weight, the viscosity may be too low.

In the step (1), it is preferable to dissolve the binder completely in a solvent by mixing the binder in 43-75 ° C. for 1-5 hours. If the binder is less than 43 ° C., the binder may be insoluble in the solvent. It is not preferable because the binder may burn out, and if it is less than 1 hour, the binder may not be completely dissolved, and if it is more than 5 hours, the economic loss may be exceeded since the binder is sufficiently dissolved. not.

In the method of manufacturing a carbon composite according to the present invention, in the step (2), the electrode active material is an activated carbon-based material having a high specific surface area, activated carbon powder, activated carbon fiber, carbon nanotube, carbon aerogel or these It is preferable to use a mixture of the electrode active material is preferably a specific surface area of 800-1,600 m 2 / g, less than 800 m 2 / g is not preferable because the adsorption capacity is lowered, fine pores above 1,600 m 2 / g It is not preferable because there are many because it may not be good for desorption.

The content of the electrode active material can be used by adjusting the content range according to the required physical properties and there is no particular limitation, for example, it is preferable that the weight ratio of the binder and the electrode active material is 1-3: 7-9, out of the range The surface adsorption capacity may be degraded, the composite may not be formed, or an electrode having a low capacitance may be manufactured, and electrical conductivity and capacitance indicating electrical characteristics of the CDI may not satisfy the conditions of the CDI.

In step (2), after adding the electrode active material to the mixture obtained in step (1), mixing the mixture at 43-75 ° C. for 4-10 hours to form a uniform slurry can synergistically improve the desired effect of the present invention. It is preferable in terms of.

Bubbles are generated when the slurry is made in step (2), and these bubbles are preferably removed by using a casting method, and are placed in a 58-80 cmHg vacuum oven for 5-20 seconds. It is preferable to remove the solution by degassing, but it is not preferable because the solvent may be evaporated out of the above range.

In the method of manufacturing a carbon composite according to the present invention, in the step (3), the support may be carbon paper or the like, but is not limited thereto. The support may be thin and flexible to keep the shape of the carbon composite flexible. Can be.

In the step (3), the method for casting the electrode active material slurry on the support using a doctor blade, and the end surface of the support is cast at 70-120 rpm using the electrode active material slurry, and then at 23-30 ℃ After drying for 20-30 hours, it is preferable to dry in an oven at 80-120 ° C. for 8-12 hours in order to completely remove the solvent remaining on the surface. It may not be desirable.

The thickness of the carbon composite obtained by the casting method may be appropriately selected so that the present invention can achieve the desired effect, but having a thickness of 0.5-1.5 mm is synergistic to the desired effect of the present invention. It is preferable at the point which can improve.

In addition, in the step (3), the method of dipping the support into the electrode active material slurry, the electrode active material slurry is contained in a container, immersed at a rate of 60-100 mm / min using the support 60-100 after 1-2 minutes It is preferable to remove at a rate of mm / min, then dry in an oven at 80-120 ° C. for 1-3 hours, and repeat the process 3-5 times, outside of this range, the electrode becomes thicker and has a large surface area. It may be rough, which is undesirable.

Then, it is preferable to dry the carbon composite obtained above in an oven at 80-120 ° C. for 8-12 hours, which is not preferable because the solvent remaining on the surface may not be completely removed.

The thickness of the carbon composite obtained by the dipping may be appropriately selected so that the present invention can achieve the desired effect, but having a thickness of 0.5-1.5 mm synergistically improves the desired effect of the present invention. It is preferable at the point which can be made.

Carbon composite for capacitive desalination electrode according to the present invention is characterized in that the electrode active material and the support is formed integrally.

The carbon composite may include a binder, a solvent, an electrode active material, and a support.

The binder used in the present invention is used to fix the position of the electrode active material, and may use one or more selected from the group consisting of polyvinylidene fluoride, polytetrafluoroethylene, and the like. none.

The solvent used in the present invention is not particularly limited in kind, and for example, at least one selected from the group consisting of N-methyl-2-pyrrolidone, dimethylacetamide, dimethylformamide, and the like can be used. However, there is no limitation thereto.

The content of the solvent is preferably 1,000 to 2,000 parts by weight with respect to 100 parts by weight of the binder, but less than 1,000 parts by weight is not preferable because the binder is not completely dissolved, and if it exceeds 2,000 parts by weight, the viscosity may be too low.

The electrode active material used in the present invention is an activated carbon-based material having a high specific surface area, and may use activated carbon powder, activated carbon fiber, carbon nanotube, carbon aerogel, or a mixture thereof. It is preferable that the specific surface area is 800-1,600 m <2> / g.

The content of the electrode active material can be used by adjusting the content range according to the required physical properties and there is no particular limitation, for example, it is preferable that the weight ratio of the binder and the electrode active material is 1-3: 7-9, out of the range The surface adsorption capacity may be reduced, or an electrode having a low capacitance may be manufactured, and electrical conductivity and capacitance indicating electrical characteristics of the CDI may not meet the conditions of the CDI.

The support used in the present invention may be used, such as carbon paper, but is not limited thereto. The support may be made thin and flexible to flexibly maintain the shape of the carbon composite.

The carbon composite according to the present invention is composed of an electrode active material slurry by dissolving a binder in a solvent and adding an electrode active material thereto, and casting the electrode active material slurry on the end face of the network structure, or supporting the network structure on the electrode active material. By dipping, the electrode active material may be obtained by being deposited and integrated on the support of the network structure.

The thickness of the carbon composite according to the present invention may be appropriately selected so that the present invention can achieve the desired effect, but having a thickness of 0.5-1.5 mm will synergistically improve the desired effect of the present invention. It is preferable in that it can.

Capacitance of the carbon composite for a desalination electrode according to the present invention is characterized by a 23 F / g or more.

The electrical conductivity of the carbon composite for capacitive desalination electrodes according to the present invention is characterized by being 0.401 S / cm or more.

The desalination rate of the capacitive desalination electrode including the carbon composite for capacitive desalination electrode according to the present invention is 70% or more.

Ultimately, the carbon composite for capacitive desalination electrode according to the present invention has excellent electrochemical properties, and thus can be applied to a capacitor.

Hereinafter, the present invention will be described in more detail with reference to the following examples, but the scope of the present invention should not be construed as being limited to these examples.

Example

Example  1: Preparation of Carbon Composite Using Casting Method

5 g of polyvinylidene fluoride (MW = 530,000) was added to 70 ml of N-methyl-2-pyrrolidone (MW = 530,000), mixed and completely dissolved at 60 ° C. for 3 hours. Then, 20 g of activated carbon powder (surface area = 1,000-1,600 m ² / g) was added to the mixture obtained above, and stirred at 60 ° C. for 6 hours so that the activated carbon slurry was sufficiently stirred. Then, the bubbles produced when the slurry was prepared were put in a 60 cmHg vacuum oven for 10 seconds to degassed to remove the bubbles.

Subsequently, the activated carbon slurry was cast at 90 rpm on a carbon paper (DONACARBO S-253 paper) as a support using a doctor blade to obtain a carbon composite having a thickness of 1 mm.

The carbon composite material was naturally dried at 25 ° C. for 1 day, and then dried in an oven at 100 ° C. for 10 hours to dry the solvent on the surface to completely remove the solvent.

Example  2: Dipping method  Preparation of Used Carbon Composites

5 g of polyvinylidene fluoride (MW = 530,000) was added to 60 ml of N-methyl-2-pyrrolidone (MW = 530,000), mixed, and then completely dissolved at 60 ° C. for 3 hours. Then, 20 g of activated carbon powder (surface area = 1,000-1,600 m ² / g) was added to the mixture obtained above, and stirred at 60 ° C. for 6 hours so that the activated carbon slurry was sufficiently stirred.

Subsequently, the activated carbon slurry was placed in a container, soaked at 85.69 mm / min speed using carbon paper (DONACARBO S-253 paper) as a support, and then withdrawn at 85.69 mm / min speed after 1 minute. Then, the carbon paper with the activated carbon slurry was dried in an oven at 100 ° C. for 2 hours.

Thereafter, the support was immersed in the activated carbon slurry, taken out, and dried in an oven two more times to obtain a carbon composite having a thickness of 1 mm.

The carbon composite was then dried in an oven at 100 ° C. for 10 hours to completely remove the solvent on the surface to completely remove the solvent.

Comparative example  One

It was prepared in the same manner as in Example 1 except that 7.5 g of activated carbon powder (surface area = 1,000-1,600 m ² / g) was added.

Comparative example  2

It was prepared in the same manner as in Example 1 except adding 95 g of activated carbon powder (surface area = 1,000-1,600 m ² / g).

Comparative example  3

Using the doctor blade was prepared in the same manner as in Example 1 except for casting the activated carbon slurry at 150 rpm on a carbon paper (DONACARBO S-253 paper) as a support.

Comparative example  4

It was immersed at 50 mm / min speed using carbon paper (DONACARBO S-253 paper) as a support, and then pulled out at 50 mm / min speed after 10 seconds. Then, the carbon paper with the activated carbon slurry was dried in an oven at 70 ° C. for 30 minutes, and then, after immersing and removing the support in the activated carbon slurry and drying in the oven once more, the carbon composite was obtained. And was prepared in the same manner as in Example 2.

Experimental Example

<Carbon Composite Characterization>

Using the untreated carbon paper (hereinafter also referred to as general carbon paper) used in the present invention and the carbon composite of Example 1, the electrical conductivity was tested to test the capacitance of the electrode and the ability as a current supply plate. Measured.

Experimental Example  1: Surface Analysis of Carbon Composites

The surface of the carbon composite was analyzed to confirm the fixation of the carbon powder by the binder. The carbon composite surface was investigated using video microscopy (EGVM 35B, EG, tech), magnified 100 and 300 times, and scanning microscopy at 200, 5 and 1 μm.

Referring to FIG. 3, the upper left photograph of FIG. 3 is an enlarged view 100 times of the surface of the carbon paper not coated with activated carbon before casting the activated carbon slurry, and the upper right photograph of FIG. 3 is the carbon composite of Example 1. 3 shows an enlarged view 100 times, and the lower left picture of FIG. 3 shows an enlarged 300 times the surface of the carbon paper not coated with activated carbon before casting the activated carbon slurry, and the lower right picture of FIG. 3 shows the carbon of Example 1 The complex is shown magnified 300 times.

The surface of the carbon paper that was not coated with activated carbon and the surface of the carbon composite material of Example 1 after the activated carbon was coated was confirmed. The carbon paper that was not coated with activated carbon was able to penetrate the activated carbon slurry well. It was confirmed that is well deposited and fixed on the carbon paper, which can be seen that the carbon composite of Example 1 that the activated carbon slurry is well penetrated and adhered to the carbon paper. Thus, it was shown that the carbon composite of Example 1 can be used as an element in a stack of CDI.

Experimental Example  2: Capacitance  Measure

The capacitance of the carbon composite was measured by cyclic voltammetry (CV). Capacitance was calculated by an equation using the results of a cyclic voltammogram.

Where c is the capacitance (F / g), I _a and I _c are the anionic and cationic currents (A), v is the scan rate (V / s) and w is the weight (g).

The sweep range was -0.6 V to +0.6 V at 100 mV / s as scan speed. The standard potential was measured by the OCV of the circuit cell. The electrolyte was prepared by 1 MH ₂ SO ₄ . Pt wire was used as counter electrode and Ag / AgCl electrode was used as reference electrode. The capacitance of the untreated carbon paper, Examples 1 and 2, and Comparative Examples 1-4 were measured to confirm the improved capacitance. The surfaces of the carbon paper, Examples 1 and 2, and Comparative Examples 1-4 were all 0.785 cm 2.

The results of the capacitances of the carbon papers, Examples 1 and 2, and Comparative Examples 1-4 are shown in FIG. 5, and the capacitances of the carbon papers, Examples 1 and 2, and Comparative Examples 1-4 are 0.18, 25.45, and 26.12, respectively. , 6.25, 33.78, 15.74 and 13.42 F / g, the higher the ratio of the activated carbon, the higher the capacitance, but Examples 1 and 2 using the casting and dipping method according to the present invention casting and dipping outside the scope of the present invention It can be seen that the capacitance is superior to Comparative Examples 3 and 4 using the method. Therefore, according to the above results, it can be confirmed that the carbon composites of Examples 1 and 2 have a capacitance capability, so that the role of the electrode can be performed.

Experimental Example  3: measurement of electrical conductivity

The electrical conductivity of the carbon composite of the carbon composite without any treatment, Examples 1 and 2, and Comparative Examples 1-4 was measured according to the 4-probe system. Electrical conductivity was calculated by the following equation.

Where σ is the electrical conductivity, L is the length of the carbon composite (cm), R is the resistance of the carbon composite (Ω), w is the width of the carbon composite (cm), and d is the thickness of the carbon composite.

Electrical conductivity was measured using carbon paper without any treatment, Examples 1 and 2, and Comparative Examples 1-4. The carbon paper was measured to compare the improved electrical conductivity of the carbon composite material. As shown in FIG. 6, the electrical conductivity of carbon paper, carbon paper, Examples 1 and 2, and Comparative Examples 1-4, which were not treated with the carbon paper, was the lowest at 0.070 S / cm, and Examples 1 and 2 were compared. Examples 1-4 showed 0.401 S / cm, 0.410 S / cm, 0.198 S / cm, 0.165 S / cm, 0.202 S / cm and 0.211 S / cm, respectively.

The electrical conductivity of Comparative Example 2 having the best capacitance was found to be low as 0.165 S / cm, which is comparative example 2 having too low content of polyvinylidene fluoride as a binder to fix the activated carbon powder firmly This is because it is not done properly, and stability is reduced.

Therefore, Examples 1 and 2 confirmed that both the capacitance and the electrical conductivity is excellent and has a capability to allow the current to be adhered to the support well and can perform a role in place of the current supply plate and the electrode of the CDI stack Can be.

Experimental Example  4: salt ( salt Removal effect

In order to confirm the desalting ability using sodium chloride feed water, the salt removal experiment of the CDI unit cell was performed at a flow rate of 2 ml / min, and a solution having a concentration of 10 ppm NaCl was used as water.

Since CDI repeats desalination and regeneration, the ion conductivity of the treated water was measured to measure the amount of ions changing. Desalting and regeneration were repeated during the desalting period of 1.5 V and 0 V during the regeneration period for 6 minutes.

The ion conductivity was changed with or without the potential difference. When the potential difference was applied, the ions were removed to obtain purified water. When the potential difference was removed, the carbon composite was regenerated.

Here, η: removal rate, C _i is the initial electrical conductivity of the feed water, C is diluted water.

As a result of calculating the salt removal efficiency according to the above equation, the results of Examples 1 and 2 and Comparative Examples 1-4 at 10 ppm of NaCl were 73%, 75%, 50%, 32.4%, 43%, 37%. It was. Therefore, Examples 1 and 2 show the applicability of the CDI stack by showing an excellent desalting effect compared to the comparative example, the specific results are shown in Table 1 below.

NaCl concentration Example 1 Example 2 Initial Conductivity (μS / cm) 21.84 23.72 Conductivity (μS / cm) 5.83 6.01 Salt removal efficiency (%) 73 75

As described above, the carbon composites of Examples 1 and 2 prepared according to the present invention have excellent electrical conductivity and capacitance, and can be applied in place of a current supply plate and an electrode as a stack of CDI. Excellent results were found above 70%.

Claims (19)

(1) adding a binder to a solvent to prepare a mixture;
(2) preparing an slurry by adding an electrode active material to the mixture;
(3) casting the electrode active material slurry obtained in the step (2) to the end face of the network structure, or dipping the support into the electrode active material slurry to deposit the electrode active material on the support of the network structure and then dry the carbon composite Obtaining Step
Since the electrode active material is deposited on the support of the network structure so as to produce a carbon composite for a capacitive desalination electrode characterized in that the integrated. The method of claim 1, wherein in the step (1), the binder is at least one selected from the group consisting of polyvinylidene fluoride and polytetrafluoroethylene, and the solvent is N-methyl-2-pyrrolidone And at least one selected from the group consisting of dimethylacetamide and dimethylformamide. The method of claim 1, wherein in the step (1), the binder is placed in a solvent and mixed for 1-5 hours at 43-75 ° C. to thereby completely dissolve the carbon composite for a capacitive desalination electrode. The method according to claim 1, wherein in the step (2), the electrode active material is activated carbon powder, activated carbon fiber, carbon nanotube, carbon aerogel or mixtures thereof, and the specific surface area of the electrode active material is 800-1,600 m 2 / g Method for producing a carbon composite for a capacitive desalination electrode, characterized in that. The method according to claim 1, wherein the weight ratio of the binder and the electrode active material is 1-3: 7-9. The method of claim 1, wherein the step (2) is a capacitive desalination, characterized in that to produce a uniform slurry by adding the electrode active material to the mixture obtained in step (1) and then mixed at 43-75 ℃ for 4-10 hours. Method for producing a carbon composite for electrodes. The method of claim 1, wherein in the step (3), the support is a carbon paper. According to claim 1, In the step (3), the method for casting the electrode active material slurry on the support using a doctor blade, and the end surface of the support is cast at 70-120 rpm using the electrode active material slurry After drying for 20-30 hours at 23-30 ℃, further drying for 8-12 hours in an oven of 80-120 ℃ characterized in that the carbon composite for a desorption electrode. The method of claim 1, wherein in the step (3), the method of dipping the support into the electrode active material slurry comprises placing the electrode active material slurry in a container, immersing at a speed of 60-100 mm / min using the support, After minutes, withdraw at 60-100 mm / min, then dry in oven at 80-120 ° C. for 1-3 hours, repeat the above procedure 3-5 times, and then 8-12 in an oven at 80-120 ° C. A method of producing a carbon composite for a capacitive desalination electrode, characterized in that drying over time. 10. The method of claim 8 or 9, wherein the carbon composite has a thickness of 0.5-1.5 mm. The electrode active material is formed by dissolving a binder in a solvent and adding an electrode active material to the slurry to form an electrode active material slurry. A carbon composite for a capacitive desalination electrode, which is formed by being deposited on a support of a network structure and being integrated. 12. The carbon composite for a capacitive desalination electrode according to claim 11, wherein the carbon composite includes a binder, a solvent, an electrode active material, and a support. The method of claim 12, wherein the binder is at least one member selected from the group consisting of polyvinylidene fluoride and polytetrafluoroethylene,
The solvent is at least one member selected from the group consisting of N-methyl-2-pyrrolidone, dimethylacetamide and dimethylformamide,
The electrode active material is activated carbon powder, activated carbon fiber, carbon nanotube, carbon aerogel or a mixture thereof, and the specific surface area of the electrode active material is 800-1,600 m 2 / g Carbon composite for capacitive desalination electrode, characterized in that. The carbon composite of claim 12, wherein the amount of the solvent is 1,000 to 2,000 parts by weight based on 100 parts by weight of the binder. The carbon composite for a desalination electrode according to claim 12, wherein a weight ratio of the binder and the electrode active material is 1-3: 7-9. delete 12. The carbon composite for a capacitive desalination electrode according to claim 11, wherein the carbon composite is produced by the production method described in any one of claims 1 to 9. 12. The carbon composite for a capacitive desalination electrode according to claim 11, wherein the carbon composite has a thickness of 0.5-1.5 mm. The carbon composite for a capacitive desalination electrode according to claim 11, wherein the carbon composite has a capacitance of 23 F / g or more, an electrical conductivity of 0.401 S / cm or more, and a desalination rate of 70% or more.

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