KR100952305B1 - Electrolytic recycle method of contaminated carbonate solution and its device - Google Patents

Abstract

The present invention relates to a method for regenerating a contaminated carbonate solution and an apparatus thereof, and an object thereof is a method for regenerating a contaminated carbonate solution for separately recovering a pure carbonate solution and a metal ion or soluble organic substance from a carbonate solution containing a metal ion or a soluble organic substance. And a device thereof.

The present invention includes a carbonate solution injection step of injecting a carbonate solution contaminated with metal ions or soluble organic matter into the anode chamber of the electrolytic cell having a cation exchange membrane; A water decomposition step of acidifying the anode room and alkalizing the cathode room by performing a water decomposition reaction in the electrolyzer into which the carbonate solution is injected; A carbon dioxide discharge step of moving carbon dioxide generated in the anode chamber by the water decomposition reaction to a lower portion of the gas absorption tower installed outside the electrolytic cell; A catholyte solution injection step of injecting a catholyte solution formed of a strong alkali solution by a catholyte movement and water decomposition reaction of the carbonate constituent cation according to the discharge of carbon dioxide from the upper side of the gas absorption tower to the lower side; Carbonate ions generated by the reaction of the negative electrode solution and carbon dioxide in the gas absorption tower is to include a carbonate recovery-discharge step that is discharged through the lower portion of the carbon dioxide absorption tower.

Carbonic acid solution, cation exchange membrane, ion migration, carbonic acid recovery, electrolytic water decomposition reaction

Description

Electrolytic recycling method of contaminated carbonate solution and its device

The present invention relates to a method for regenerating a contaminated carbonate solution and a device thereof, wherein only a carbonate component is moved from a carbonate solution contaminated with a metal ion or a soluble organic substance injected into an anode chamber using a separate electrolytic reactor having a cation exchange membrane. And a method for regenerating contaminated carbonic acid solution for separating and recovering a pure carbonate solution and a metal ion or soluble organic substance separately from a carbonic acid solution containing a metal ion or a soluble organic substance by leaving a source of contamination of a metal ion or a soluble organic substance in the anode chamber. It is about.

The domestic patent 1997-7000678 is for producing alkaline water and acidic water by electrolytic method, and the domestic patent 1983-0001416 is an alkali hydroxide in which the alkali chloride metal is injected into the anode room in the electrolytic cell using the cation exchange membrane and is produced in the catholyte solution. A technique for converting a solution into an alkali metal carbonate solution by introducing carbon dioxide from the outside into the solution is described.

In addition, Japanese Patent Application Laid-Open No. 2004-275841 is an invention for preparing strong alkaline water for use in detergents in a cathode chamber by injecting potassium carbonate into an anode chamber using a cation exchange membrane and passing through a cation exchange membrane. -71449 also relates to an invention for making alkaline water by preventing deposits generated in an electrolytic cell when making alkaline water using a cation exchange membrane, and Japanese Patent Laid-Open No. 8-141573 is for producing high purity water used for semiconductor manufacturing. A solution in which a carbonate is dissolved is injected into an anode chamber having a cation exchange membrane to convert carbonate to carbon dioxide through acidification of the solution by water decomposition reaction, and then neutralized by mixing the de-carbonated acid solution with an alkaline cathode solution. The invention relates to an invention for obtaining a high-purity semiconductor manufacturing process number.

In addition, US Patent 5,853,562 is for removing the calcium carbonate scale formed in the membrane electrolytic cell by the electrolytic method, US Patent 4,049,519 carbonate using an electrodialysis electrolytic method having a series of cations, anion exchange membrane or a combination thereof The present invention relates to an invention in which a solution is decarbonated by acidification through an electrolytic decomposition reaction and the remaining sodium ions are transferred to another cathode through an additional cation exchange membrane to produce a sodium hydroxide solution.

As described above, although there are many patents regarding a method of producing acidic or alkaline water using an electrolytic cell having a cation exchange membrane, a carbonic acid solution containing impurities such as metal ions, metal ions and organic substances by an electrolytic method using a cation exchange membrane. The invention for separating these materials from carbonates in Korea and abroad has not been shown to date.

The present invention provides a pure carbonate solution and a metal ion or solubility from a carbonate solution containing metal ions or soluble organics by moving only the carbonate component from the contaminated carbonate solution to the cathode room and leaving the source of contamination of the metal ions or soluble organics in the anode room. It is an object of the present invention to provide a method for regenerating contaminated carbonate solution and an apparatus for separating and recovering organic matters.

Another object of the present invention is to provide a method and apparatus for regenerating contaminated carbonate solution which can minimize the amount of waste and recycling of carbonate or economically valuable material by separately recovering pure carbonate solution and metal ions or soluble organics. will be.

The present invention is intended for the treatment and recycling of carbonates used in the fields of carbonate fuel cells, plastics processing, paints, and the like, in the case of dissolving nuclear fuel used in a nuclear power plant in a carbonate-based solution by using a carbonate solution system. The carbonate is separated from the carbonate solution contaminated with bivalent or more metal ions, anions and dissolved organics by using an electrolytic reactor having a cation exchange membrane for recycling the carbonate solution in a manner that minimizes secondary waste generation. It is an object of the present invention to provide a method for regenerating contaminated carbonate solution and a device for removing or recycling carbonate or a substance mixed with carbonate, respectively.

An object of the present invention is to provide a method for regenerating a polluted carbonic acid solution and an apparatus for producing an alkaline carbonic acid solution by injecting carbon dioxide emitted from an anode chamber acidified by a water decomposition reaction into an absorption tower connected to a cathode chamber.

The present invention includes a carbonate solution injection step of injecting a carbonate solution contaminated with metal ions or soluble organic matter into the anode chamber of the electrolytic cell having a cation exchange membrane; A water decomposition step of acidifying the anode room and alkalizing the cathode room by performing a water decomposition reaction in the electrolyzer into which the carbonate solution is injected; A carbon dioxide discharge step of moving carbon dioxide generated in the anode chamber by the water decomposition reaction to a lower portion of the gas absorption tower installed outside the electrolytic cell; A catholyte solution injection step of injecting a catholyte solution formed of a strong alkali solution by a catholyte movement and water decomposition reaction of the carbonate constituent cation according to the discharge of carbon dioxide from the upper side of the absorption tower to the lower side; And a carbonate recovery-discharge step of discharging carbonate ions generated by the catalytic reaction of the cathode solution and carbon dioxide in the gas absorption tower through the lower portion of the gas absorption tower.

In the cathode chamber of the electrolyzer, a weak alkaline solution having a positive ion component constituting a carbonate solution injected into the anode chamber is injected.

Carbon dioxide generated in the anode chamber in the carbon dioxide discharge step is separated through a gas-liquid separator and injected into the lower portion of the gas absorption tower.

The carbon dioxide in the absorption tower is converted into carbonate ions by the hydroxide ions of the cathode solution.

As such, the present invention can be utilized to minimize recycling of carbonates or economically valuable materials and waste generation by separating carbonates and pollutants from carbonate solutions contaminated with various metal ions or organic substances in the field of using carbonate solutions. have.

In addition, the present invention recovers the carbonate solution using an electrochemical method without using any chemicals, so that almost no liquid waste is generated in the process, thereby having high environmental friendliness.

In addition, the present invention is applied to the treatment of the carbonate solution used for the removal of uranium (U) from the spent fuel, it is possible to regenerate and circulate the carbonate solution, through which the disposal capacity of the high-level waste disposal site in the disposal of spent fuel There is an effect such as to improve.

The present invention is to inject a carbonate solution containing impurities of metal ions or dissolved organic matter using an electrolytic cell having a cation exchange membrane to move the carbonate from the anode to the cathode room and to separate the carbonate and impurities while remaining metal ions or organic matter in the anode room. It is.

That is, the present invention includes a carbonate solution injection step of injecting a carbonate solution contaminated with metal ions or soluble organic matter into the anode chamber of the electrolytic cell having a cation exchange membrane; A water decomposition step of acidifying the anode room and alkalizing the cathode room by performing a water decomposition reaction in the electrolyzer into which the carbonate solution is injected; A carbon dioxide discharge step of moving carbon dioxide generated in the anode chamber by the water decomposition reaction to a lower portion of the gas absorption tower installed outside the electrolytic cell; An alkali solution injection step of injecting a cathode solution formed of a strong alkaline solution into the upper portion of the absorption tower from the upper side of the absorption tower by a cathodic discharge and water decomposition reaction of the carbonate-containing cation according to the discharge of the carbon dioxide; And a carbonate recovery-discharge step in which carbonate ions generated by the reaction of the alkali solution and carbon dioxide injected into the absorption tower are discharged through the lower portion of the carbon dioxide absorption tower.

In the carbonate solution injection step, a weak alkaline solution having a cationic component constituting the carbonate solution injected into the cathode chamber of the electrolytic cell is injected. That is, as an example, when a solution having sodium carbonate (Na ₂ CO ₃ ) as the carbonate solution is injected into the anode chamber, a sodium hydroxide (NaOH) solution is injected into the cathode chamber.

In addition, in the carbonate solution injection step, when the amount of metal ions present as impurities in the carbonate solution injected into the anode chamber is small, when the carbonate is eliminated by the decarbonation process in the anode chamber, the electrical conductivity of the anode solution is reduced and the electrolytic cell voltage is decreased. To prevent this, the electrolytic reaction may be abruptly stopped, so that bivalent or higher metal ions or soluble organic substances injected into the anode chamber are not supported in the carbonate solution containing impurities (hereinafter referred to as 'target carbonate solution'). It further comprises the step of mixing a small amount of supporting electrolyte (Supporting electrolyte).

In the water decomposition step, the target carbonate solution and the above-mentioned supporting electrolytic mixed solution in the anode chamber are decomposed in an electrolytic cell in which a weak alkali solution is respectively injected in the cathode chamber, thereby lowering the pH to 4 or less in the anode chamber. That is, the solution of the anode room is lowered to pH 4 or less by hydrogen ions generated by the decomposition reaction of water. As a result, carbonate ions (CO ₃ ^2- ), which are anions, are converted into carbon dioxide and exit the anode room together with the anode solution. Come out.

At this time, the ions constituting the carbonate remaining in the solution as the anion carbonate ions are released from the solution of the anode room is moved to the cathode room in order to maintain the electrical neutrality of the cathode solution. A strong alkaline solution is produced by the hydroxide ions produced by the cations and the cations of carbonates from the anode room.

In this case, the cation exchange membrane of the electrolyzer passes +1 alkali metal ions (Li ⁺ , Na ⁺ , K ⁺ , Cs ^+, etc.), but very little +2 metal passes and +3 or more metal ions, anions and dissolution. Organic substances, etc. cannot be passed.

The carbon dioxide discharge step is to separate the carbon dioxide discharged from the anode chamber and to move to the gas absorption tower, when converted into carbon dioxide and exiting the anode chamber together with the anode solution, acidification having carbon dioxide gas and impurities in the gas-liquid separator Anolyte solution is separated. At this time, the carbon dioxide separated through the gas-liquid separator is injected into the lower portion of the absorption tower and moved upwards, and the acidified anode solution having impurities is discharged to the outside.

In the alkaline solution injection step, a strong alkali solution is generated by the hydroxide ions generated by the decomposition reaction of water and the cation of the carbonate from the anode chamber, and the resulting solution of the cathode chamber is injected into the upper part of the gas absorption tower and flows from the upper side to the lower side. To do that.

As such, the carbon dioxide gas separated from the gas-liquid separator is injected into the lower part of the absorption tower, and the strong alkaline solution generated in the cathode chamber is injected into the upper part of the absorption tower, so that the carbon dioxide is all carbonate ions (HCO ₃₎ in the absorption tower. ^- , CO ₃ ^2- ). That is, the carbon dioxide injected into the lower part of the absorption tower is contacted with the alkali solution injected into the upper part of the absorption tower in the absorption tower, and is converted back into carbonate ions by the hydroxide ions of the strong alkaline solution.

Said separation discharging step is the carbonate ion generated by the reaction of carbon dioxide with strong alkali solution, ^- and it exits from the absorber bottoms ^{_{(HCO 3, CO 3 2-)}} , oxygen and hydrogen gas produced at the anode cathode-school room, The pure carbonate solution and impurities are separated from the carbonate solution containing impurities discharged from the top of the absorption tower and injected into the anode chamber of the initial electrolytic cell.

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

1 is a schematic view showing a configuration according to the present invention, the present invention is provided with a cation exchange membrane, the target carbonate solution is injected into the anode chamber (3), the weak alkaline solution is injected into the cathode chamber (2) An electrolytic cell 7, a gas-liquid separator 4 connected to the anode chamber 3 of the electrolytic cell 7, and a lower portion of the gas-liquid separator 4 connected to the cathode chamber 2 of the electrolytic cell are connected. The gas absorption tower 5 connected to the upper portion is included.

The anode chamber 3 of the electrolytic cell is further connected with a solution mixer 6 for mixing the target carbonate solution and the supporting electrolytic solution.

That is, the present invention is connected to the anode chamber (3) of the electrolytic cell having a cation exchange membrane (1) so that the carbonic acid solution exiting the solution mixer (6) for mixing the target carbonate solution and the supporting electrolyte solution is injected, the cathode chamber (2) Into the anode, a weak alkaline solution having the same component as the cation constituting the target carbonate solution is injected.

In addition, a gas-liquid separator 4 for separating the acidic solution containing carbon dioxide, oxygen gas and impurities discharged from the anode chamber 3 is provided, and the gas separated by the gas-liquid separator 4 is separated. It is injected from the lower part of the gas absorption tower 5 so as to flow from the lower part to the upper direction, and from the upper part of the gas absorption tower 5 so that the hydrogen gas and the strong alkali solution discharged from the cathode chamber 2 flow from the upper part to the lower direction. The carbon dioxide is converted into carbonate ions (CO ₃ ^2- ) by the hydroxide ions (OH ⁻ ) of the alkaline solution, and then discharged from the lower portion of the gas absorption tower (5), and oxygen generated in the anode and cathode rooms. And hydrogen gas are to be discharged from the top of the absorption tower.

Hereinafter, the present invention will be described in more detail.

In the present invention, the carbonate ion carbonate (carbonate, CO ₃ ^2-), bicarbonates (bicarbonate, HCO ₂ ^-) depending on the pH and has a characteristic that transformation in sequence with, carbon dioxide (CO _2).

Moreover, the solution by the decomposition of water in the anode room of the electrolytic reactor which has a cation exchange membrane is acidified, and the solution of the solution by the decomposition reaction of water in the cathode room is provided.

The present invention is to use the above characteristics to separate the pure carbonate and metal ions or organic groups from the target carbonate solution so that they can be regenerated and used respectively.

As shown in FIG. 2, the carbonate ions are changed according to pH by a reaction represented by Equation 1) to Equation 4) below. That is, in the pH 12 over CO ₃ ^2- in the form and, pH 8 in HCO ₂ ^- and in the form, in the pH 4 or less H ₂ CO ₃ present in one form, H ₂ CO ₃ is unstable and changed to CO ₂ The amount of carbon dioxide above the solubility of CO ₂ is released to the atmosphere.

On the other hand, in the conductive solution, the reaction of generating oxygen and hydrogen changes in the positive electrode and the negative electrode, respectively, according to the acidity of the solution. At the anode under acidic conditions, water is directly decomposed to produce hydrogen ions (H ⁺ ), while at the anode under alkaline conditions, the solution is acidified by dropping alkalinity due to the consumption of hydroxide ions (OH ⁻ ). The cathode of the acidic conditions of hydrogen ion and hydroxyl ion direct reduction (OH ^-) by the decomposition of water directly in the cathode of the alkaline conditions teurigo drop the acidity thereby Chemistry alkaline solution to generate a.

In the present invention, the carbonate solution having impurities of metal ions or soluble organic matter is injected into the anode chamber of the electrolytic cell having the cation exchange membrane by using the carbonic acid solution characteristic and the electrolytic reaction characteristic. By oxidizing OH ⁻ in the carbonic acid solution to oxygen and acidifying the solution.

The solution is acidified and the CO ₃ ^2- in the carbonic acid solution is converted to carbon dioxide from pH 8 or below via HCO ₂ ^- and exited out of the solution. The solution is always electrically so have a neutral, positive ions, for example anions of CO ₃ ^2- in the carbonate solution disappears is left alone in the solution Na ₂ CO ₃ when the acid solution disappears is CO ₃ ^2- Na ⁺ in the solution are Since they cannot be left alone, they migrate through the cation exchange membrane to the cathode room by electrical migration.

In general, cation exchange membranes pass ⁺ 1-valent alkali metal ions (Li ⁺ , Na ⁺ , K ⁺ , Cs ^+, etc.), but pass very little + 2-valent metals and more than + 3-valent metal ions, anions and dissolved organics. Material and the like cannot be passed through. When the + 1-valent cations to the five advance to the negative electrode chamber a cathode chamber is also water as the formula 6), equation (8)) to conform electrolyzing electroneutrality, and hydrogen is released hydroxide ions (OH ^- to) room to create a negative electrode Alkaline the solution. When the carbon dioxide gas is in contact with the alkali solution, it can be converted back to the carbonate solution by the reactions of the above formulas 1) to 3), so that the carbon dioxide gas has a sufficient gas-liquid contact area installed outside the electrolytic cell. When the alkali solution generated in the cathode chamber is flowed and the carbon dioxide gas discharged from the anode chamber is injected into the lower part of the absorption tower, all carbon dioxide generated from the carbonate solution is recovered in the anode chamber.

Therefore, in the target carbonate solution containing the metal ions or organics initially injected into the anode room by the above-described series of operations, only the carbonate is moved to the cathode room, and the remaining metal ions or organics are left in the anode room, thereby being injected into the anode room. The pollutant and carbonate of the contaminated carbonate solution are separated.

At this time, if all of the carbonate solution is moved from the anode room to the cathode room, the electrical conductivity of the anode solution is lowered, so that the operation can be stopped due to the increase of the cell voltage of the electrolytic cell, so that the electrical conductivity of the carbonate solution injected into the anode room is kept constant. The target carbonate solution is mixed with the supporting electrolytic solution before being injected into the anode room.

Hereinafter, the present invention will be described in detail by way of examples.

Example 1

An electrolytic cell equipped with a cation exchange membrane (Dupont Nafion 424) and a gas absorption tower having a porosity of 40% by filling a glass tube having a diameter of 2.5 cm and a volume of 100 ml with about 1.2 mm are configured as shown in FIG. A batch electrolysis system was configured to circulate the anode solution from the gas-liquid separator and the cathode solution from the absorption tower into the anode and cathode chambers, respectively, and then the anode solution had only 100 ml of Na ₂ CO ₃ 0.5 M carbonate without supporting electrolyte. When the solution was used as a cathode solution 100ml, 0.1M NaOH and a current of 1.36A was applied to the electrolyzer, the pH of the solution leaving the anode chamber and the absorption tower over time, the cell voltage at that time, and the solution leaving the anode chamber and the absorption tower. The change in the carbonic acid concentration of was observed, and the results are shown in FIGS. 3 and 4.

Figure 3 is an embodiment showing the change in pH and cell voltage with time in the anode chamber and the lower portion of the carbon dioxide absorption tower when using only 0.5 M, Na ₂ CO _{3 as the} anode solution, Figure 4 is the lower portion of the anode chamber and carbon dioxide absorption tower in Figure 3 Figure 2 shows an example of the change in carbonic acid concentration over time, and as the electrolytic reaction occurs, the anode room is acidified, the pH drops, the decarbonate process occurs, the carbonic acid concentration falls, and the carbon dioxide exiting the anode room is negative. Absorption tower carbonate solution is absorbed from the absorption tower by alkali solution from the room, but the absorption tower carbonate concentration gradually increases, but as the pH of the anolyte solution reaches 8, the de-carbonization process rapidly progresses, so that the solution electrical conductivity drops and the cell voltage is supplied. It can be seen that the electrolytic reaction is interrupted upon reaching the device's limit voltage, and the movement of carbonate is very small. Can.

Example 2

An electrolytic cell equipped with a cation exchange membrane (Dupont Nafion 424) and an absorption tower having a porosity of 40% by filling silica with a diameter of 2.5 cm and a volume of about 100 mm in a glass tube having a volume of 2.5 cm were configured as shown in FIG. -Batch electrolytic system configured to circulate the anode solution from the liquid separator and the cathode solution from the absorption tower into the anode and cathode chambers respectively, and then 400 ppm of Mo ⁺⁴ and 400 ppm of Zr ⁺⁴ in 0.5M Na ₂ CO ₃ In addition, using a positive electrode solution having 0.1 M Na ₂ SO ₄ supporting electrolyte, pH and cell voltage change over time in the anode chamber and the lower part of the carbon dioxide absorption tower, and the carbonic acid concentration of the solution leaving the anode chamber and the absorption tower were observed. The results are shown in FIG. 5 and FIG. 6.

FIG. 5 shows the anode room and carbon dioxide absorption when the anode solution having 400 ppm of Mo (IV) and 400 ppm of Zr (IV) and a 0.1 M Na ₂ SO ₄ support electrolyte in 0.5 M Na ₂ CO ₃ is used. Figure 6 shows an example showing the change in pH and cell voltage with time at the bottom of the column, Figure 6 shows an example showing the change in carbonic acid concentration with time of the solution exiting the anode chamber and the carbon dioxide absorption tower in Figure 5, 5 is different from FIG. 4 as the electrolytic reaction occurs, the pH of the anode room shows two inflection points and falls below pH 1, and as shown in FIG. 6, the carbonic acid concentration of the anode room drops rapidly from pH 8 to pH 2 or less. It can be seen that this is almost zero, and the concentration of the solution exiting the bottom of the absorption tower absorbing this carbon oxide emitted from the anode chamber is 0.45 M, taking into account the amount of carbonate ions remaining in the absorption tower. If the concentration of carbonate recovered from the absorption tower is about 0.5 M, it can be seen that all the carbonate injected in the initial anode room is moved to the cathode room. At this time, Mo, Zr and SO ₄ ^2- used as the supporting electrolyte in the anode room did not move to the cathode room at all, and it was confirmed that the cathode room remained.

The results of the above Examples 1 and 2 show that carbonates and impurities can be recovered from carbonate solutions containing impurities such as metal ions and soluble organic substances by using the electrolytic system configured as shown in FIG. 1.

The present invention is not limited to the above-described specific preferred embodiments, and various modifications can be made by any person having ordinary skill in the art without departing from the gist of the present invention claimed in the claims. Of course, such changes will fall within the scope of the claims.

1 is a schematic view showing a configuration according to the present invention

2 is an exemplary view showing a change characteristic of carbonate ions according to pH conversion

3 is a diagram showing changes in pH and cell voltage over time in the anode chamber and the absorption tower bottom according to Example 1;

Figure 4 is an embodiment showing a change in carbonic acid concentration with time in the anode chamber and the carbon dioxide absorption tower according to Example 1

FIG. 5 is a view showing changes in pH and cell voltage with time in an anode chamber and a lower portion of a carbon dioxide absorption tower according to Example 2; FIG.

Figure 6 is an embodiment showing a carbonic acid concentration change with time of the solution exiting the anode chamber and the carbon dioxide absorption tower according to Example 2

* Explanation of symbols for main parts of the drawings

(1): cation exchange membrane (2): electrolytic cell cathode chamber

(3): electrolytic cell anode chamber (4): gas-liquid separator

(5): gas absorption tower (6): solution mixer

(7): electrolytic cell

Claims (8)

A carbonate solution injection step of injecting a carbonate solution contaminated with metal ions or soluble organic matter into an anode chamber of an electrolytic cell having a cation exchange membrane; A water decomposition step of acidifying the anode room and alkalizing the cathode room by performing a water decomposition reaction in an electrolytic cell into which a carbonate solution is injected; A carbon dioxide discharge step of moving carbon dioxide generated in the anode chamber by the water decomposition reaction to a lower portion of the gas absorption tower installed outside the electrolytic cell; An alkali solution injection step of injecting a cathode solution formed of a strong alkaline solution into a cathode from a top of a gas absorption tower by a cathode dissipation and water decomposition reaction of a carbonate-containing cation according to the discharge of carbon dioxide; And a carbonate recovery-discharge step in which carbonate ions generated by the reaction of the alkali solution and carbon dioxide injected into the absorption tower are discharged through the lower portion of the carbon dioxide absorption tower. The method according to claim 1; And a weak alkaline solution having a cation component constituting a carbonate solution injected into the anode chamber is injected into the cathode chamber of the electrolytic cell. The method according to claim 1; The carbonate solution injecting step may further include a step of mixing a small amount of a supporting electrolyte which does not participate in the reaction with a carbonate solution having impurities of a divalent or higher metal ion or soluble organic substance injected into the anode room. Regeneration method of carbonic acid solution. The method according to claim 1; The water decomposition step decomposes the water in the electrolytic cell, thereby reducing the pH in the anode room to pH 4 or less regeneration method. The method according to claim 1; The carbon dioxide that is injected from the gas absorption as tapnae absorber bottoms are contacted with an alkaline solution injected into the absorber overhead gas in the absorption tower, a carbonate ion by the hydroxide ions of the strong alkali solution, ^- a (HCO _3, CO ₃ ^2-) Method for regeneration of contaminated carbonate solution, characterized in that converted. An electrolyzer having a cation exchange membrane, injecting a target carbonate solution into the anode chamber, and injecting an alkaline solution into the cathode chamber; A gas-liquid separator connected to the anode chamber of the electrolytic cell, The gas-liquid separator and the lower portion is connected, and the regeneration apparatus of the contaminated carbonate solution, characterized in that it comprises a gas absorption tower connected to the upper portion of the cathode chamber of the electrolytic cell. The method according to claim 6; And a solution mixer for mixing the target carbonate solution and the supporting electrolyte solution is further connected to the anode chamber of the electrolytic cell. The method according to claim 6; The gas absorption tower is a regeneration device of contaminated carbonate solution, characterized in that the gas absorption tower filled with silica.

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