KR100770736B1 - Ceramic Electrode for Water Treatment And Making Method of The Same and Electrode Apparatus using The Same - Google Patents

Abstract

The present invention minimizes the loss of current and at the same time induces a current only to the surface of the electrochemical reaction to minimize the power ratio and to prevent the temperature rise due to the heating of the electrode, and a method and manufacturing method It is about.

The ceramic electrode for water treatment of the present invention has a ceramic base material and an iridium (Ir) compound, a ruthenium (Ru) compound, and a tin (Sn) compound as main components on the surface of the ceramic base material, and includes a titanium (Ti) compound and molybdenum And a coating layer formed of a compound including at least one selected from a (Mo) compound, a tantalum (Ta) compound, and a zirconium (Zr) compound.

Water treatment, ceramic electrode

Description

Ceramic Electrode for Water Treatment and Manufacturing Method Thereof and Electrode Construct Using the Same {Ceramic Electrode for Water Treatment And Making Method of The Same and Electrode Apparatus using The Same}

1 is a photograph showing a bead-shaped and plate-shaped ceramic prepared according to an embodiment of the present invention,

2a and 2b is a photograph showing a ceramic electrode after the coating treatment with the ceramic shown in Figure 1,

3 and 4 are views and photographs showing an electrode structure made using the bead-shaped ceramic electrode shown in FIG.

5 is a process chart for explaining a method of manufacturing a ceramic electrode for water treatment according to the present invention.

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a ceramic electrode for water treatment, a method for manufacturing the same, and an electrode structure using the same, and more particularly, an amount of power consumption of an electrode used when electrolyzing wastewater, electrolyzing water, or electrolysis of salt. The present invention relates to an improved ceramic electrode for water treatment, a method for manufacturing the same, and an electrode structure using the same, which can reduce the amount of water and increase the decomposition rate.

Generally, three elements of an electrochemical system include a cathode, an anode, and an electrolyte. When an electrochemical reaction occurs, the cathode reduces metal, forms a plating layer, and generates hydrogen gas. A reduction reaction occurs, and an oxidation reaction such as dissolution of a metal electrode, generation of oxygen and chlorine gas occurs at the anode, and the electrolyte provides an improvement in conductivity by supplying ions necessary for such a reaction.

Here, the reaction at the electrode is a heterogeneous reaction due to the movement of electrons across the interface between the electrode and the solution. The reaction rate is affected by the type, property and shape of the electrode, but the electrode itself Since it does not change afterwards, the electrode material is generally regarded as a catalyst in the electrode reaction and is called a catalyst electrode (electro-catalysis).

As such, the selection of an appropriate electrode material in the electrochemical reaction is very important and, as described above, plays a very important role in the optimization of the electrode reaction, which is a very important part in the electrochemical reaction research.

In particular, since the anode greatly influences the redox rate of the electrochemical reaction according to its characteristics, it is a very important factor in the industrial electrolytic process system based on electrochemistry.

These anodes are divided into consumable anodes and non-consumable anodes. The double consumable anode is a metal electrode, which is reduced at the cathode to prevent ion depletion and depletion in the electrolyte. For example, the required copper anode is used, and the non-consumable anode does not participate in the reaction by providing only a place for the anode reaction, but rather dissolves the anode itself. Therefore, the non-consumable anode is an electrochemical catalyst electrode. Also called electrocatalytic electodes, dimensionally stable anodes (DSA) in chlor-alkali processes, carbon anodes in aluminum smelting processes, platinum anodes in precious metal plating processes, and anodes in electrical methods. Representative example.

That is, the electrode using the electrochemical reaction is mainly the electrode surface reaction using the positive electrode and the negative electrode, it is important to select the appropriate electrode for the positive electrode and the negative electrode.

On the other hand, electrolysis of a general aqueous solution is a reaction in which hydrogen is generated at the cathode and oxygen is generated at the anode. At the anode, the generation of oxygen by the oxidation of water or OH ⁻ occurs competitively. Since the chlorine generating reaction is thermodynamically unstable because is lower than the chlorine generating reaction, the electrode used as the anode should have a large overpotential for oxygen generation and a small overpotential for chlorine generation.

The anode material having a high oxygen overvoltage includes platinum group elements such as Pt and Ir, but has a disadvantage that the price is very expensive.

Therefore, development of an electrode having a relatively low cost while having excellent oxygen overvoltage and durability of elements of the platinum group has been required. Accordingly, titanium, zirconium, and tantalum are alternative materials for platinum-based elements. The study of anode materials using metals such as molybdenum, columbium, tungsten, etc. was actively conducted in the mid-20th century.

However, these metals have high electrical conductivity and excellent durability in an acidic or alkaline aqueous solution, but when electricity is applied, an oxide film is formed on the electrode surface, and the resistance rapidly increases due to the growth of the oxide film, thereby ultimately losing performance as an electrode. The problem is shown.

Therefore, in the early 1950s, studies on the oxide catalyst electrode having conductivity by injecting heterogeneous elements into the TiO ₂ lattice using the semiconductor properties of the oxide film of TiO ₂ formed on the surface of titanium began, and the diamond Shamrock Technology (Diamond Shamrock Technology) began. The DSA (Dimensionally Stable Anode) electrode made by incorporating TiO ₂ into commercially developed RuO ₂ has been used for oxide catalyst electrode, but RuO ₂ is eluted to RuO ₄ by oxygen generated from the anode. There has been a problem of losing the catalytic activity.

In order to solve such a problem, an insoluble oxide catalyst electrode was manufactured, and a general method of manufacturing an insoluble oxide catalyst electrode is a metal layer, nitride, hydrate, etc., which provides a precious metal element, mixed with a brush or coated on the electrode surface to form a coating layer. After thermal decomposition, the activity varies depending on the type, ratio, heat treatment temperature, time, pretreatment method of the electrode, and the like.

For example, in US Pat. No. 3,711,385, an electrode was prepared by directly coating a platinum group element on metal titanium. In US Pat. No. 4,528,084, an electrode was thermally decomposed by adding hydrochloric acid (HCl) to iridium, rhodium, and ruthenium compounds on a titanium base. US Pat. No. 5,587,058 discloses an electrode having a coating solution of ₂₀ to 28 mol% IrO ₂ and ₂ to 6 mol% RuO ₂ mainly based on 70 to 75 mol% of TiO ₂ on a titanium matrix.

In addition, Korean Patent No. 403,235 discloses a method of preparing a coating liquid based on ruthenium-iridium-titanium and an electrode pretreatment method through hydrochloric acid etching without using oxalic acid, which is a conventional substrate etching method.

However, coating base materials such as titanium, zirconium, and tantalum used in these electrodes are generally known to have excellent corrosion resistance and chemical resistance, but high temperature hydrochloric acid solution (2 ~ 3wt%, 100 ℃), high concentration hydrochloric acid solution (15 ~ 37wt%, 35 ℃), methyl alcohol (99%, 60 ℃), oxalic acid (0-10wt%, 60-100 ℃), hydrofluoric acid (1wt%, room temperature), sulfuric acid (1-5wt%, 35 ℃) The solution has the problem of causing severe corrosion.

Therefore, in order to increase the corrosion resistance of such a base material, products having enhanced corrosion resistance by treating tantalum (0.1 wt%) in titanium alloy composition or treatment such as atmospheric oxidation, anodization, and precious metal coating, which are one of corrosion resistant surface treatments, have been released. . However, such corrosion-resistant surface treatment can slow down the corrosion rate of the titanium base material, but it is difficult to provide perfect corrosion resistance. For example, the surface treatment of the insoluble oxide catalyst film, which is a kind of precious metal coating, is mostly produced by pyrolysis. Therefore, the surface of the catalyst electrode has a grain boundary that is relatively weak compared to the surface when electricity is applied due to the formation of grain boundary cracks during densification during ceramic sintering. The electrons are emitted along the surface to expand the grain boundary cracks, and as a result, the base material is exposed and damaged.

In addition, the conventional electrode is accelerated the life of the catalyst electrode in an environment that damages the base material, thereby limiting the role as an insoluble electrode, the titanium base material has an electrical resistivity of 40mΩ · cm, compared to copper (1.7mΩ · cm) 25 Since it is about twice as high as the electrode in various water treatments, there is a problem of increasing the temperature of the solution by heating the titanium base material by the amount of power, that is, the power ratio and the electrical resistance.

In addition, Korean Patent No. 0553364 proposed by the present applicant discloses a metal mixed oxide electrode in which a highly efficient coating layer excellent for removing various ionic compounds, hardly decomposable substances, etc. is formed on a titanium electrode substrate having fine irregularities formed on a surface thereof, and a manufacturing method thereof. Is disclosed.

However, since the base metal is also limited to a metal such as titanium, the conventional metal mixed oxide electrode has a problem of various electrode damages caused by the use of the metal base material.

Accordingly, the present invention has been made in view of the problems of the prior art, the purpose of which is an electrolytic cell and electrolysis having problems such as environment or excessive power ratio, temperature rise due to heat generation, which cannot be used conventional electrode using an electrochemical reaction The present invention provides a ceramic electrode for water treatment, a method of manufacturing the same, and an electrode structure using the same.

In addition, another object of the present invention is to form a conductive insoluble oxide catalyst coating layer on a ceramic base material having excellent corrosion resistance, abrasion resistance, chemical resistance, and the like, and to charge electricity in a solution or a conductive medium instead of directly applying electricity. The present invention provides a highly efficient water treatment ceramic electrode, a method of manufacturing the same, and an electrode structure using the same by controlling electrons and charges on the surface of the ceramic base material and coating a compound having various compositions on the surface.

In addition, another object of the present invention, by using a non-conductive ceramic as a base material to prevent the current flow to the inside to minimize the loss of current and at the same time to induce the current only to the surface of the electrochemical reaction to minimize the power ratio It is to provide a method for solving the problem of temperature rise caused by the heating of the electrode.

Other objects and advantages of the invention will be described below and will be appreciated by the embodiments of the invention. Furthermore, the objects and advantages of the present invention can be realized by means and combinations indicated in the claims.

In order to achieve the above object, according to a first aspect of the present invention, the present invention comprises a ceramic base material; On the surface of the ceramic base material, iridium (Ir) compound, ruthenium (Ru) compound and tin (Sn) compound are main components, and titanium (Ti) compound, molybdenum (Mo) compound, tantalum (Ta) compound and zirconium It provides a ceramic electrode for water treatment consisting of; a coating layer formed of a compound containing at least one selected from (Zr) compound.

According to a second aspect of the present invention, an iridium (Ir) compound, a ruthenium (Ru) compound, and a tin (Sn) compound are mainly composed on a ceramic base material and the surface of the ceramic base material, and a titanium (Ti) compound, A plurality of ceramic electrodes comprising a coating layer formed of a compound including at least one selected from a molybdenum (Mo) compound, a tantalum (Ta) compound, and a zirconium (Zr) compound; A frame into which the plurality of ceramic electrodes can be charged in a single layer type; It is coupled to the frame provides an electrode structure using a ceramic electrode comprising a fixed mesh to fix the plurality of ceramic electrodes do not flow down.

According to a third aspect of the invention, (a) preparing a ceramic base material; (b) Iridium (Ir) compounds, ruthenium (Ru) compounds and tin (Sn) compounds as main components, including titanium (Ti) compounds, molybdenum (Mo) compounds, tantalum (Ta) compounds and zirconium (Zr) compounds Mixing at least one selected from an organic solvent to obtain a coating solution; (c) applying the coating solution to the ceramic base material and drying it; (d) heat treating the ceramic base material passed through step (c); and (e) repeating steps (c) and (d). Forming a coating layer; It provides a method of producing a ceramic electrode for water treatment, comprising the step (f) the final heat treatment of the ceramic base material (e).

Here, the heat treatment of step (d) is preferably made for 10 to 30 minutes at 400 ~ 700 ℃ temperature in the oxidizing atmosphere.

In addition, the final heat treatment of step (f) is preferably made for 3 to 10 hours at 400 ~ 700 ℃ temperature in the oxidizing atmosphere.

As described above, the present invention is excellent in corrosion resistance, abrasion resistance, chemical resistance, etc., since the ceramic is used as a base material, and by forming an insoluble oxide catalyst coating layer having excellent conductivity on the surface of the ceramic base material, thereby providing a particle filling electrode such as electrolysis. It is possible to control the electrons and charges on the surface of the ceramic base material by charging the electricity in a solution or conductive medium rather than directly applying electricity, and by coating the surface of the ceramic base material with various compositions A ceramic electrode for water treatment can be obtained.

In addition, the method of manufacturing a ceramic electrode according to the present invention forms a coating layer on the surface of the ceramic base material, thereby preventing current flow into the ceramic electrode as a non-conductor, minimizing the loss of current and at the same time only the surface where the electrochemical reaction occurs By inducing a current to minimize the power ratio it can prevent the temperature rise by the heating of the electrode.

On the other hand, in the case of the ceramic electrode, the surface electrode is mainly a catalytic electrode, and the electrode potential, that is, the oxygen generation potential and the chlorine generation potential on the electrode surface varies according to the change in composition, but the ruthenium electrode has a low chlorine generation potential. hypochlorite (OCl ^-) generation industry, and is applied to a chlorine disinfection, is used for an iridium-based electrode when chlorine generating potential than the oxygen evolution potential is low, waste water treatment, the positive electrode for the plating.

Accordingly, the ceramic electrode of the present invention composed of the iridium-ruthenium complex composition can be used in general for both the most common oxygen generating electrode and chlorine generating electrode.

On the other hand, the heat treatment carried out in the method of manufacturing a ceramic electrode of the present invention is carried out to give a bonding force between the coating liquid and the ceramic base material dried at a low temperature, the process is carried out for 10 to 30 minutes at 400 ~ 700 ℃ temperature in an oxidizing atmosphere It is repeated 4 to 15 times.

Here, when the number of repetitions of the heat treatment process is less than four times, the formation of the coating layer may not be sufficiently developed, so that the coating layer may be peeled off from the ceramic used as the base material during electrolysis. Excessive growth may result in low electrical conductivity, requiring a high voltage.

In this case, the repeated number of times of the heat treatment process may be applied a small number of times if the thickness of the coating layer is sufficiently thick. On the other hand, if the thickness of the coating layer is too thick, the electrical conductivity may be low, which may make it difficult to transmit current for electrolysis. Therefore, the thickness of the coating layer should be secured to allow smooth electrolysis without peeling.

On the other hand, the final heat treatment is carried out to give sufficient bonding strength and surface strength by sufficiently growing the coated oxide particles, it is performed for 3 to 10 hours at a temperature of 400 ~ 700 ℃ in an oxidizing atmosphere.

In addition, each element according to the method of manufacturing a ceramic electrode according to the present invention may use various compounds capable of supplying precious metals or metal ions, that is, nitrides, sulfides, hydrates, and the like, preferably chlorides.

Hereinafter, the present invention will be described in detail with reference to the accompanying drawings.

1 is a photograph showing a bead-shaped and plate-shaped ceramic electrode manufactured according to the present invention, Figures 2a and 2b is a photograph showing a ceramic electrode after the coating treatment with the ceramic shown in FIG.

First, referring to Figures 1 to 2b, the ceramic electrode according to the present invention is alumina beads, zirconia beads, other ceramics (also available in Zeolite form) beads or plate (plate type) or cylindrical, elliptical, tetrapot type, Ceramic supports of various shapes such as hexahedral (hexahedral porosity) can also be used.

In this case, the ceramic base material is a powder form of a single component or a composite selected from alumina, titania, zirconia, zirconia, zeolite, mullite, ferrite, silica, and silica. It can be molded by compression.

In addition, since the coating layer of the present invention is a catalytic reaction in the case of a ceramic electrode, the surface reaction is mainly a catalyst reaction, and thus, when the thickness of the coating layer is formed that can transmit current without peeling, the performance as an electrode is maintained, wherein the thickness of the coating layer is water treatment. Ceramic electrode used in the field can prevent the occurrence of erosion due to friction with the ionic compound in the aqueous solution, and approximately 3 to prevent the desorption of the coating layer by the minute hydrogen air bubbles generated on the electrode surface It is preferable that it is -10 micrometers.

This is because when the thickness of the coating layer is less than 3 μm, the coating layer may be damaged by friction or hydrogen air bubbles. When the thickness is more than 10 μm, coarse or abnormal grains are formed by sintering during the thermal decomposition of the compound. This is because there is room for peeling off.

3 and 4 are photographs showing the electrode structure using the bead-shaped ceramic electrode shown in Figure 2a and a view for explaining the same.

Referring to the drawings, the electrode assembly 10 according to the present invention, as shown in Figure 3, in order to have an excellent conductivity, a plurality of bead-shaped ceramic base material formed on the surface of the coating layer formed by the coating solution of the chloride described above ( 1) was inserted into a single layer through the frame 3 and fixed using a fixed mesh 2, and FIG. 4 is a photograph of the electrode assembly 10.

Herein, the frame and the fixed mesh may be made of polyethylene, polypropylene, or ABS resin (Acrylonitrile Butadiene Styrene copolymer), and the polyethylene and polypropylene may have high chemical resistance. It is because it has insulation.

5 is a process chart for explaining a method of manufacturing a ceramic electrode for water treatment according to the present invention.

Referring to the drawings, the method for preparing the coating solution is composed of iridium (Ir) compound, ruthenium (Ru) compound, tin (Sn) compound in isopropyl alcohol (S22) which is an organic solvent, and titanium (Ti) compound, molybdenum At least one selected from the (Mo) compound, tantalum (Ta) compound, and zirconium (Zr) compound (S23) is weighed and added (S23), and then dispersed and mixed for 1 hour using an ultrasonic disperser.

This is stirred for 2 hours using a magnetic stirrer for complete dissolution of the coating solution dispersed (S24).

Then, the ceramic base material is washed with organic solvents and distilled water (S12, S13) to wash the fine dust and contaminants present on the surface, and then dried until the water is completely evaporated in a hot air drying furnace at 100 ° C. S14).

The dried ceramic base material is dipped into the coating liquid, or the coating liquid is applied using a brush or spray (S31) and then dried in a hot air drying furnace at 100 to 150 ° C. for 10 to 20 minutes (S32).

Then, heat treatment for 10 to 20 minutes in an electric furnace of 400 ~ 700 ℃ for smooth coupling of the dried coating solution and the ceramic base material (S33). At this time, when the heat treatment time is excessively over, the oxide layer grains of the coating composition may grow on the ceramic surface, and thus, an adverse effect of lowering the electrical conductivity of the electrode during repeated coating may occur.

After the heat treatment, the cooled ceramic base material is re-coated with the coating solution, and then dried and heat-treated in the same manner as above. The process is performed 4 to 15 times in total.

Then, the final heat treatment for 3 to 10 hours at 400 ~ 700 ℃ for the smooth growth of the oxide layer (S40). At this time, the reason for limiting the temperature condition to 400 ~ 700 ° C is that the temperature of 400 ° C or less is not enough to transform the noble metal or transition metal chloride, which is a coating raw material, into a complete oxide by pyrolysis. Since some oxides are bonded to each other to form a composite phase, or a large amount of crystal grains are formed by the sintering effect, the heat treatment temperature conditions are suitable 400 ~ 700 ℃.

(Example)

1. Pretreatment of Ceramic Base Materials

To prepare a ceramic electrode, alumina beads having diameters of 5, 10, and 20 mm, respectively, were ultrasonically washed for 5 minutes in acetone-ethanol-distilled water order, and then dried in a vacuum oven at 100 ° C. for 1 hour to remove surface moisture.

2. Coating solution manufacture

1.0 g of IrCl ₃ nH ₂ O (Aldrich. Co.), 0.5 g of RuCl ₃ nH ₂ O (Aldrich. Co.), in 20 cc of isopropyl alcohol (IPA; Mallinckrodt. Co.) for preparing the coating solution 0.5 g SnCl ₃ (Aldrich. Co.), 2 g TaCl ₅ (Aldrich. Co.), 0.1 g ZrCl ₄ (Aldrich. Co.), 0.1 g MoCl ₅ (Aldrich. Co.) and 3 cc TiCl ₄ (Junsei. Co.) was added and then stirred until completely dissolved to prepare a desired coating solution.

3. Ceramic Electrode Manufacturing

(A) Apply coating liquid to ceramic base material and dry

After dipping the dried alumina beads into the prepared coating solution, the solvent was first dried at 100 ° C. to evaporate IPA.

(B) Primary heat treatment and repeated execution

Heat treatment was performed for 10 minutes in presbyopia at 550 ° C. for particle growth of the coating solution by pyrolysis on the surface of alumina beads.

(C) final heat treatment

In order to improve durability of the alumina bead surface coating layer, the above-described process was repeatedly performed six times, followed by heat treatment at 550 ° C. for 10 hours to finally prepare a ceramic electrode.

4. Test

In order to evaluate the decomposition behavior of ammonia nitrogen using the manufactured ceramic electrode, a reactor of 1000ml capacity was manufactured, and then a frame was prepared to allow alumina beads to be loaded into a single layer, and then fixed by using a polyethylene fixed mesh. In addition, the characteristics of the dimensionally stable anode (DSA) manufactured by coating an insoluble material (RuO ₂ , IrO _2, etc.) on a titanium base material and the ceramic electrode manufactured by the present invention were compared with each other.

At this time, NH ₄ Cl was dissolved in distilled water to decompose ammonia nitrogen to prepare a simulated liquid having a concentration of 500 ppm of ammonia nitrogen. A small amount (5 g) of NaCl was added as a supporting electrolyte to increase the conductivity of the powder. Stir until fully dissolved in this solution, the conductivity of the final solution was 10mS / cm.

One liter of the simulated liquid is charged into a batch reactor. Decomposition experiments were performed by applying a constant current of 60 mA / cm ² for 8 minutes with each electrode reaction area of 10 ㅧ 5cm. The results of the decomposition experiments are shown in Table 1.

division Ceramic electrode DSA NH ₃ -N Degradation Rate 95.0% 95.0% Voltage 17.0V 29.5 V electric current 2.84A 2.84A power 48.28w 83.78w

Table 1 prepared by Examples of the present invention This table shows the test results of ceramic electrodes using ceramic beads and conventional dimensional stable anodes (hereinafter referred to as DSA).

Referring to Table 1, when comparing the ceramic electrode using the ceramic beads according to the embodiment of the present invention and the conventional DSA, the NH ₃ -N decomposition rate of the ceramic electrode of the present invention and the conventional DSA was equally set to 95.0%. In this case, the required voltage was 58% lower, and the required power was 58% lower.

Therefore, the ceramic electrode according to the embodiment of the present invention can greatly reduce the power consumption ratio compared to the equivalent effect compared to the conventional DSA.

As described above, the ceramic electrode for water treatment, the method of manufacturing the same, and the electrode structure using the same provide the following effects.

First, the life of the general DSA is generally about 2 to 5 years, whereas using a ceramic base material can increase the life of the electrode to the extent that the life can be extended semi-permanently.

Second, when using a ceramic (bead, plate etc) electrode, the same decomposition rate is produced, and compared to general DSA, the power cost can be greatly reduced to 50 ~ 60% level, and the higher the electrical conductivity of the wastewater, the smoother the charging occurs. The efficiency can be improved.

Third, compared with the case of using Ti as the base material, the ceramic base material of the present invention can reduce the cost compared to the same performance by about 20% can significantly reduce the material cost.

Fourth, fluoride (F ^-) in the waste water by using the DSA with the Ti base metal under the conditions that includes such components, if hayeoteul but is difficult to apply with a serious damage to the base material, using a ceramic electrode of the present invention is not damaged The range of application can be expanded.

As described above, although the present invention has been described by way of limited embodiments and drawings, the present invention is not limited thereto and is intended by those skilled in the art to which the present invention pertains. Of course, various modifications and variations are possible within the scope of equivalents of the claims to be described.

Claims (16)

Ceramic base material; On the surface of the ceramic base material, iridium (Ir) chloride, ruthenium (Ru) chloride and tin (Sn) chloride are main components, and titanium (Ti) chloride, molybdenum (Mo) chloride, tantalum (Ta) chloride and zirconium (Zr) a coating layer formed of chloride comprising at least one selected from chlorides; ceramic electrode for water treatment, characterized in that consisting of. delete The method of claim 1, wherein the thickness of the coating layer is a ceramic electrode for water treatment, characterized in that 3 ~ 10㎛. The ceramic electrode for water treatment according to claim 1, wherein the ceramic base material is formed by compressing at least one powder form selected from alumina, titania, zirconia, zeolite, mullite, ferrite, and silica. The ceramic electrode according to claim 1, wherein the ceramic base material is any one selected from bead shape, plate shape, cylindrical shape, oval shape, tetrapot shape, and hexahedral shape. On the surface of the ceramic base material and the ceramic base material, iridium (Ir) compound, ruthenium (Ru) compound, and tin (Sn) compound are mainly composed of titanium (Ti) compound, molybdenum (Mo) compound, and tantalum (Ta). A plurality of ceramic electrodes comprising a coating layer formed of a compound including at least one selected from a compound and a zirconium compound; A frame into which the plurality of ceramic electrodes can be charged in a single layer type; And a fixed mesh coupled to the frame to fix the plurality of ceramic electrodes so that the plurality of ceramic electrodes do not flow down. The electrode assembly according to claim 6, wherein each element compound of the coating layer is a chloride. 7. The electrode assembly according to claim 6, wherein the ceramic base material is formed by compressing at least one powder form selected from alumina, titania, zirconia, zeolite, mullite, ferrite, and silica. 7. The electrode assembly according to claim 6, wherein the frame and the fixed mesh are any one selected from polyethylene, polypropylene or ABS resin. 7. The electrode assembly according to claim 6, wherein the ceramic base material is any one selected from bead shape, plate shape, cylinder shape, oval shape, tetrapot shape and hexahedral shape. (a) preparing a ceramic base material; (b) Iridium (Ir) compounds, ruthenium (Ru) compounds and tin (Sn) compounds as main components, including titanium (Ti) compounds, molybdenum (Mo) compounds, tantalum (Ta) compounds and zirconium (Zr) compounds Mixing at least one selected from an organic solvent to obtain a coating solution; (c) applying the coating solution to the ceramic base material and drying it; (d) heat-treating the ceramic base material having undergone the step (c); (e) repeating steps (c) and (d) to form a coating layer; And (F) a method of producing a ceramic electrode for water treatment, comprising the step of performing a final heat treatment of the ceramic base material (e). 12. The method of claim 11, wherein each of the elemental compounds of step (b) is a chloride. The method of claim 11, wherein the ceramic base material of step (a) is prepared by compressing and molding at least one powder form selected from alumina, titania, zirconia, zeolite, mullite, ferrite and silica. Way. The method of claim 11, wherein the coating layer has a thickness of about 3 μm to about 10 μm. The method of claim 11, wherein the heat treatment of step (d) is performed for 10 to 30 minutes at 400 to 700 ° C in an oxidizing atmosphere. The method of claim 11, wherein the final heat treatment of step (f) is performed for 3 to 10 hours at 400 to 700 ° C in an oxidizing atmosphere.

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