阅读说明：本技术 用于减少微尘的废气净化系统 (Exhaust gas purification system for reducing fine dust ) 是由 金建兑 金昌珉 金正原 梁礼真 成亚临 于 2020-03-12 设计创作，主要内容包括：本技术涉及用于对含有作为微尘的发生原因的氮氧化物和硫氧化物的废气进行净化的废气净化系统,该系统可以在通过电化学反应对含有氮氧化物和硫氧化物的废气进行净化而去除诸如微尘的空气中的污染物的同时产生作为环保燃料的氢气。(The present technology relates to an exhaust gas purification system for purifying exhaust gas containing nitrogen oxides and sulfur oxides as causes of generation of fine dust, which can produce hydrogen gas as an environmentally friendly fuel while removing pollutants in the air such as fine dust by purifying the exhaust gas containing nitrogen oxides and sulfur oxides through an electrochemical reaction.)

1. An exhaust gas purification system comprising:

a cathode portion including a first accommodation space, a first aqueous solution, and a cathode at least a portion of which is immersed in the first aqueous solution;

an anode part including a second receiving space, a second aqueous solution that is alkaline, and an anode of metal, at least a portion of the anode being immersed in the second aqueous solution; and

a connection part connecting the cathode part and the anode part,

wherein the anode is made of aluminum (Al) or zinc (Zn),

injecting a gas containing nitrogen oxides (NOx) into the first aqueous solution,

the nitrogen oxides injected into the first aqueous solution react with water to produce nitric acid (HNO)₃)，

The nitric acid supplies hydrogen ions, and

the hydrogen ions react with the electrons of the cathode to produce hydrogen gas.

2. An exhaust gas purification system comprising:

a cathode portion including a first accommodation space, a first aqueous solution, and a cathode at least a portion of which is immersed in the first aqueous solution;

an anode part including a second receiving space, a second aqueous solution that is alkaline, and an anode of metal, at least a portion of the anode being immersed in the second aqueous solution; and

a connection part connecting the cathode part and the anode part,

wherein the anode is made of aluminum (Al) or zinc (Zn),

injecting a gas containing sulfur oxides (SOx) into the first aqueous solution,

the sulfur oxides injected into the first aqueous solution react with water to form sulfuric acid (H)₂SO₄)，

Said sulfuric acid supplying hydrogen ions, and

the hydrogen ions react with the electrons of the cathode to produce hydrogen gas.

3. The exhaust gas purification system according to claim 1 or 2, wherein the connection portion is provided between a first accommodation space and the second accommodation space, and is an ion transport member of a porous structure that blocks movement of the first aqueous solution and the second aqueous solution and allows movement of ions.

4. An exhaust gas purification system according to claim 3, wherein the material of the ion transport member is glass.

5. The exhaust gas purification system according to claim 4, wherein the ion transport member has pores formed therein of 40 to 90 micrometers, 15 to 40 micrometers, 5 to 15 micrometers, or 1 to 2 micrometers.

6. The exhaust gas purification system according to claim 1 or 2, wherein the cathode portion has a first outlet that discharges the generated hydrogen gas, and the first outlet is located above a water surface of the first aqueous solution.

7. An exhaust gas purification system as claimed in claim 1 or 2, wherein the exhaust gas further comprises fine dust having a particle diameter of 0.01 μm to 100 μm, and

the mote is slurried in the first aqueous solution of the first holding space.

8. An exhaust gas purification system comprising:

a reaction space containing an aqueous solution;

a cathode, at least a portion of the cathode being immersed in the aqueous solution in the reaction space; and

an anode of a metallic material, at least a portion of the anode being immersed in the aqueous solution in the reaction space,

wherein the anode is made of vanadium (V), chromium (Cr), manganese (Mn), iron (Fe), cobalt (Co), nickel (Ni), copper (Cu), aluminum (Al) or zinc (Zn),

the nitrogen oxides injected into the aqueous solution react with water to produce nitric acid (HNO)₃) And an

The nitric acid supplies hydrogen ions, and the hydrogen ions react with electrons of the cathode to produce hydrogen gas.

9. An exhaust gas purification system comprising:

a reaction space containing an aqueous solution;

a cathode, at least a portion of the cathode being immersed in the aqueous solution in the reaction space; and

an anode of a metallic material, at least a portion of the anode being immersed in the aqueous solution in the reaction space,

wherein the anode is made of vanadium (V), chromium (Cr), manganese (Mn), iron (Fe), cobalt (Co), nickel (Ni), copper (Cu), aluminum (Al) or zinc (Zn),

the sulfur oxides injected into the aqueous solution react with water to form sulfuric acid (H)₂SO₄) And an

The sulfuric acid supplies hydrogen ions, and the hydrogen ions react with electrons of the cathode to generate hydrogen gas.

10. An exhaust gas purification system according to claim 8 or 9, wherein the reaction space has a first outlet for discharging the produced hydrogen gas, and the first outlet is located above a water surface of the aqueous solution.

11. An exhaust gas purification system as claimed in claim 8 or 9, wherein the exhaust gas further comprises fine dusts having a particle diameter of 0.01 μm to 100 μm,

wherein the mote is slurried in the aqueous solution of the reaction space.

12. An exhaust gas purification system comprising:

a cathode portion including a first accommodation space, an aqueous electrolyte, and a cathode at least a portion of which is immersed in the aqueous electrolyte;

an anode portion including a second receiving space, an electrolyte that is alkaline, and an anode of a metal, at least a portion of the anode being immersed in the electrolyte; and

a solid electrolyte disposed between the cathode portion and the anode portion to selectively pass metal ions ionized by the metal,

wherein a gas containing nitrogen oxides (NOx) is injected into the aqueous electrolyte,

the nitrogen oxides injected into the aqueous electrolyte react with water to form nitric acid (HNO)₃)，

The nitric acid supplies the hydrogen ions and,

the hydrogen ions react with the electrons of the cathode to produce hydrogen gas, an

In the case where a gas containing nitrogen oxide (NOx) is injected into the aqueous electrolyte of the cathode portion, reactions such as the following [ equation 1] and [ equation 12] occur:

[ reaction formula 1]

NOx+H₂O→2HNO₃(aq)

[ reaction formula 12]

2Na(s)+2HNO₃(aq)→H₂(g)+2NaNO₃(aq)。

13. An exhaust gas purification system comprising:

a cathode portion including a first accommodation space, an aqueous electrolyte, and a cathode at least a portion of which is immersed in the aqueous electrolyte;

an anode portion including a second receiving space, an electrolyte that is alkaline, and an anode of a metal, at least a portion of the anode being immersed in the electrolyte; and

a solid electrolyte disposed between the cathode portion and the anode portion to selectively pass metal ions ionized by the metal,

wherein a gas containing sulfur oxide (SOx) is injected into the aqueous electrolyte,

the sulfur oxides injected into the aqueous electrolyte react with water to form sulfuric acid (H)₂SO₄)，

The sulfuric acid supplies hydrogen ions and,

the hydrogen ions react with the electrons of the cathode to produce hydrogen gas, an

In the case where a gas containing sulfur oxide (SOx) is injected into the aqueous electrolyte of the cathode portion, reactions such as the following [ reaction formula 2] and [ reaction formula 13] occur:

[ reaction formula 2]

SOx+H₂O→H₂SO₄(aq)

[ reaction formula 13]

2Na(s)+H₂SO₄(aq)→H₂(g)+Na₂SO₄(aq)。

14. An exhaust gas purification system as claimed in claim 12 or 13, wherein the solid electrolyte is composed of Na₃Zr₂Si₂PO₁₂And (4) forming.

15. An exhaust gas purification system according to claim 12 or 13, wherein the material of the anode is sodium metal.

16. The exhaust gas purification system according to claim 12 or 13, wherein the cathode portion has a first outlet that discharges the generated hydrogen gas, and the first outlet is located above a water surface of the aqueous electrolyte.

17. An exhaust gas purification system as claimed in claim 12 or 13, wherein the exhaust gas further comprises fine dust having a particle size of 0.01 μm to 100 μm, and

the mote is slurried in the aqueous electrolyte of the first containment space.

18. An exhaust gas purification system comprising:

a reaction vessel forming a reaction space;

an aqueous electrolyte solution contained in the reaction space and including chloride anions;

a cathode, at least a portion of which is immersed in the aqueous electrolyte solution in the reaction space;

an anode, at least a portion of which is immersed in the aqueous electrolyte solution in the reaction space; and

a power source electrically connected to the cathode and the anode,

wherein a gas containing nitrogen oxide (NOx) is injected into the aqueous electrolyte solution,

the nitrogen oxides injected into the aqueous electrolyte solution react with water to generate nitric acid (HNO)₃) And an

The nitric acid supplies hydrogen ions, and the hydrogen ions react with electrons of the cathode to produce hydrogen gas.

19. An exhaust gas purification system comprising:

a reaction vessel forming a reaction space;

an aqueous electrolyte solution contained in the reaction space and including chloride anions;

a cathode, at least a portion of which is immersed in the aqueous electrolyte solution in the reaction space;

an anode, at least a portion of which is immersed in the aqueous electrolyte solution in the reaction space; and

a power source electrically connected to the cathode and the anode,

wherein a gas containing sulfur oxide (SOx) is injected into the aqueous electrolyte solution,

the sulfur oxides injected into the aqueous electrolyte solution react with water to form sulfuric acid (H)₂SO₄) And an

The sulfuric acid supplies hydrogen ions, and the hydrogen ions react with electrons of the cathode to generate hydrogen gas.

20. The exhaust gas purification system according to claim 18, wherein the exhaust gas purification system adjusts an amount of chlorine gas generated at the anode such that an amount of nitrogen oxides (NOx) dissolved in the aqueous electrolyte solution is maintained above a set value, thereby maintaining the pH of the aqueous electrolyte solution above a set value.

21. The exhaust gas purification system according to claim 19, wherein the exhaust gas purification system adjusts an amount of chlorine gas generated at the anode such that an amount of sulfur oxides (SOx) dissolved in the aqueous electrolyte solution is maintained above a set value, thereby maintaining the pH of the aqueous electrolyte solution above a set value.

22. The ballast water treatment system using the exhaust gas purification system according to claim 18 or 19, wherein the electrolyte aqueous solution includes any one or more selected from the group consisting of sodium chloride, potassium chloride, and calcium chloride.

23. The exhaust gas purification system according to claim 18 or 19, wherein a material of the cathode is carbon paper, carbon fiber, carbon felt, carbon cloth, metal foam, metal thin film, platinum catalyst, or a combination thereof.

24. The exhaust gas purification system according to claim 18 or 19, wherein a material of the anode is vanadium (V), chromium (Cr), manganese (Mn), iron (Fe), cobalt (Co), nickel (Ni), copper (Cu), aluminum (Al), or zinc (Zn).

25. An exhaust gas purification system as claimed in claim 18 or 19, wherein the reaction vessel has a hydrogen gas discharge portion that discharges the generated hydrogen gas, and the hydrogen gas discharge portion is located above a water surface of the electrolyte aqueous solution.

26. An exhaust gas purification system as claimed in claim 18 or 19, wherein the exhaust gas further comprises fine dust having a particle size of 0.01 μm to 100 μm, and

the mote is slurried in the aqueous electrolyte solution in the reaction space.

Technical Field

The present technology relates to an exhaust gas purification system for reducing fine dust, which can purify exhaust gas containing nitrogen oxides and sulfur oxides as causes of generation of fine dust by an electrochemical reaction and generate hydrogen gas.

Background

Recently, with industrialization, emission of greenhouse gases is continuously increasing, and recently, the problem of air pollution caused by fine dusts is emerging. The fine dust is a pollutant having a particle size ranging from 0.1 μm to 10 μm, and among the fine dust, fine dust having a diameter of 10 μm or less (PM 10 grade) is a dust particle that is fine and invisible to the naked eye and causes respiratory diseases, and ultrafine fine dust having a diameter of 2.5 μm or less (PM 2.5 grade) penetrates deeply into human alveoli due to its very fine particle size of 1/30, which is about the thickness of hair, and becomes a direct cause of respiratory diseases. Typical gas phase pollutants that cause the formation of fine dust are sulfur oxides (SOx), nitrogen oxides (NOx), Volatile Organic Compounds (VOCs), ammonia (NH3), and the like.

Such a generated fine dust is mainly generated in a power plant, a waste incineration process, a furnace and an electric arc furnace in an iron and steel making process, a heat treatment facility, a petroleum refining process, a petrochemical manufacturing process, and the like. In order to remove fine dust particles and nitrogen oxides discharged from these industrial processes, methods such as electrostatic precipitators, filter bag precipitators, and Selective Catalytic Reduction (SCR) have been used.

In the case of an electric dust collector, the principle of static electricity by corona discharge is utilized, and there are disadvantages as follows: initial installation costs and operation costs are high, and the electric resistance is affected depending on the type of dust particles, and therefore, it is necessary to deal with this. In the case of the filter dust collecting apparatus, there are disadvantages as follows: dust or the like needs to be removed by physical impact when it is accumulated in the dust collection filter, but this causes damage to the dust collection filter or a reduction in efficiency, and requires additional equipment or additional cost for removing the dust, and when the dust concentration is high or the filtering speed is fast, a dust layer is not easily shaken off the dust collection filter due to the nature of the dust itself, or the shaken off dust is reattached to an adjacent filter, thereby degrading the dust collection performance. In the case of selective catalytic reduction, there are advantages in that the installation cost and the operation cost are low since a catalytic reactor is not required, but there are disadvantages in that the reaction rate needs to be maintained at a high level and the nitrogen oxide removal efficiency is as low as 60% or less.

As a prior patent document related to the technical field of the present technology, korean patent laid-open publication No. 10-1395594 discloses a composite purification apparatus for harmful gases in which composite pollutants are discharged together.

Disclosure of Invention

Solves the technical problem

The present technology aims to provide an exhaust gas purification system that removes nitrogen oxides (NOx) as a fine dust generating substance by an electrochemical reaction.

Another object of the present technology is to provide an exhaust gas purification system that removes sulfur oxides (SOx) as a fine dust generating substance by an electrochemical reaction.

It is still another object of the present technology to provide an exhaust gas purification system that can produce high-purity hydrogen gas as an environmentally friendly fuel using the above nitrogen oxides (NOx) or sulfur oxides (SOx).

It is still another object of the present technology to provide an exhaust gas purification system capable of slurrying and removing fine dusts of 0.01 μm to 100 μm included in the exhaust gas.

Solving means

In order to achieve the above object of the present technology, according to one aspect of the present technology, there is provided an exhaust gas purification system including: a cathode portion including a first accommodation space, a first aqueous solution, and a cathode at least a portion of which is immersed in the first aqueous solution; an anode part including a second receiving space, a second aqueous solution that is alkaline, and an anode of metal, at least a portion of the anode being immersed in the second aqueous solution; and a connecting part connecting the cathode part and the anode part, wherein a gas containing nitrogen oxide (NOx) is injected into the first aqueous solution, and the nitrogen oxide injected into the first aqueous solution reacts with water to generate nitric acid (HNO)₃) The nitric acid supplies hydrogen ions, and the hydrogen ions react with electrons of the cathode to produce hydrogen gas.

According to another aspect of the present technology, there is provided an exhaust gas purification system including: a cathode portion including a first accommodation space, a first aqueous solution, and a cathode at least a portion of which is immersed in the first aqueous solution; an anode part including a second receiving space, a second aqueous solution that is alkaline, and an anode of metal, at least a portion of the anode being immersed in the second aqueous solution; and a connecting part connecting the cathode part and the anode part, wherein a gas containing sulfur oxide (SOx) is injected into the first aqueous solution, and the sulfur oxide injected into the first aqueous solution reacts with water to generate sulfuric acid (H)₂SO₄) The sulfuric acid supplies hydrogen ions, and the hydrogen ions react with electrons of the cathode to generate hydrogen gas.

According to still another aspect of the present technology, there is provided an exhaust gas purification system including: a reaction space containing an aqueous solution; a cathode at least a portion of which is immersed in the aqueous solution in the reaction space; and an anode of a metal material at least a part of which is immersed in the aqueous solution in the reaction space, wherein the nitrogen oxide and water injected into the aqueous solutionReaction to produce nitric acid (HNO)₃) The nitric acid supplies hydrogen ions, and the hydrogen ions react with electrons of the cathode to produce hydrogen gas.

According to still another aspect of the present technology, there is provided an exhaust gas purification system including: a reaction space containing an aqueous solution; a cathode at least a portion of which is immersed in the aqueous solution in the reaction space; and an anode of a metallic material at least a portion of which is immersed in the aqueous solution in the reaction space, wherein sulfur oxide injected into the aqueous solution reacts with water to generate sulfuric acid (H)₂SO₄) The sulfuric acid supplies hydrogen ions, and the hydrogen ions react with electrons of the cathode to generate hydrogen gas.

According to still another aspect of the present technology, there is provided an exhaust gas purification system including: a cathode portion including a first accommodation space, an aqueous electrolyte, and a cathode at least a portion of which is immersed in the aqueous electrolyte; an anode portion including a second receiving space, an electrolyte that is alkaline, and an anode of a metal, at least a portion of the anode being immersed in the electrolyte; and a solid electrolyte disposed between the cathode part and the anode part to selectively pass metal ions ionized by the metal, wherein a gas containing nitrogen oxide (NOx) is injected into the aqueous electrolyte, and the nitrogen oxide injected into the aqueous electrolyte reacts with water to generate nitric acid (HNO)₃) The nitric acid supplies hydrogen ions, and the hydrogen ions react with electrons of the cathode to produce hydrogen gas.

According to still another aspect of the present technology, there is provided an exhaust gas purification system including: a cathode portion including a first accommodation space, an aqueous electrolyte, and a cathode at least a portion of which is immersed in the aqueous electrolyte; an anode portion comprising a second receiving space, an alkaline electrolyte and a metallic anode, at least a portion of said anode being immersed in said electrolyte; and a solid electrolyte disposed between the cathode part and the anode part to selectively pass metal ions ionized by the metal, wherein a gas containing sulfur oxide (SOx) is introducedInjected into the aqueous electrolyte, sulfur oxides injected into the aqueous electrolyte react with water to produce sulfuric acid (H)₂SO₄) The sulfuric acid supplies hydrogen ions, and the hydrogen ions react with electrons of the cathode to generate hydrogen gas.

According to still another aspect of the present technology, there is provided an exhaust gas purification system including: a reaction vessel forming a reaction space; an aqueous electrolyte solution contained in the reaction space and including chloride anions; a cathode at least a portion of which is immersed in the aqueous electrolyte solution in the reaction space; an anode at least a portion of which is immersed in the aqueous electrolyte solution in the reaction space; and a power supply electrically connected to the cathode and the anode, wherein a gas containing nitrogen oxide (NOx) is injected into the aqueous electrolyte solution, and the nitrogen oxide injected into the aqueous electrolyte solution reacts with water to generate nitric acid (HNO)₃) The nitric acid supplies hydrogen ions, and the hydrogen ions react with electrons of the cathode to produce hydrogen gas.

According to still another aspect of the present technology, there is provided an exhaust gas purification system including: a reaction vessel forming a reaction space; an aqueous electrolyte solution contained in the reaction space and including chloride anions; a cathode at least a portion of which is immersed in the aqueous electrolyte solution in the reaction space; an anode at least a portion of which is immersed in the aqueous electrolyte solution in the reaction space; and a power supply electrically connected to the cathode and the anode, wherein a gas containing sulfur oxide (SOx) is injected into the aqueous electrolyte solution, and the sulfur oxide injected into the aqueous electrolyte solution reacts with water to generate sulfuric acid (H)₂SO₄) The sulfuric acid supplies hydrogen ions, and the hydrogen ions react with electrons of the cathode to generate hydrogen gas.

ADVANTAGEOUS EFFECTS OF INVENTION

According to the present technology, all the objects of the present technology described above can be achieved. Specifically, it is possible to purify exhaust gas containing nitrogen oxides and sulfur oxides by spontaneous electrochemical reactions without an external power source, and to generate electric power and hydrogen gas.

Drawings

Fig. 1 is a schematic diagram showing an operation process of an exhaust gas purification system according to an embodiment of the present technology.

Fig. 2 is a schematic diagram showing an operation process of an exhaust gas purification system according to another embodiment of the present technology.

Fig. 3 is a schematic diagram showing an operation process of an exhaust gas purification system according to still another embodiment of the present technology.

Fig. 4 is a schematic view showing an operation process of an exhaust gas purification system according to still another embodiment of the present invention.

DETAILED DESCRIPTION OF EMBODIMENT (S) OF INVENTION

In the present technology, nitrogen oxides (NOx) are a general term for nitrogen oxides. Although not limited thereto, there may be, for example, Nitric Oxide (NO), nitrogen dioxide (NO)₂) Or ions thereof.

In this technique, sulfur oxide (SOx) is a general name for sulfur oxide. Although not limited thereto, it may be, for example, sulfur dioxide (SO)₂) Sulfur trioxide (SO)₃) Or ions thereof.

In the present technology, the fine dust means a carbon compound, an organic substance, an inorganic substance, a metal or a salt thereof having a size of 0.01 μm to 100 μm.

Hereinafter, the configuration and operation of the embodiment of the present technology will be described in detail with reference to the drawings.

Fig. 1 shows the configuration of an exhaust gas purification system according to an embodiment of the present technology. Referring to fig. 1 for explanation, an exhaust gas purification system 100a according to an embodiment of the present technology includes: a cathode portion 110 including a first receiving space 111, a first aqueous solution 115, and a cathode 118, at least a portion of the cathode 118 being immersed in the first aqueous solution 115; an anode part 150 including a second receiving space 151, a second aqueous solution 155 which is alkaline, and a metal anode 158, at least a portion of the anode 158 being immersed in the second aqueous solution 155; and a connection portion 190 connecting the cathode portion 110 and the anode portion 150.

Exhaust gas purification System 100a according to one embodiment of the present technologyThe spontaneous redox reaction uses nitrogen oxides (NOx) or sulfur oxides (SOx) contained in exhaust gas as pollutants as a raw material to generate electricity and hydrogen (H) as an environmentally friendly fuel₂)。

The cathode portion 110 has a first aqueous solution 115 and a cathode 118, wherein the first aqueous solution 115 is contained in the first containing space 111, and at least a portion of the cathode 118 is immersed in the first aqueous solution 115.

The first aqueous solution 115 may use an alkaline aqueous solution (in this embodiment, an alkaline solution of 1m naoh is used), an alkaline electrolyte aqueous solution, an electrolyte aqueous solution including chloride ions, seawater, tap water, and distilled water, and the like.

The cathode 118 is an electrode for forming a circuit, which may be carbon paper, carbon fiber, carbon felt, carbon cloth, metal foam, metal thin film, or a combination thereof, and a platinum catalyst may also be used. In the case of the catalyst, in addition to the platinum catalyst, a carbon-based catalyst, a carbon-metal-based composite catalyst, a perovskite oxide catalyst, and the like are included, and all other catalysts that can be generally used as an oxygen evolution reaction (HER) catalyst are included.

The cathode portion 110 has a first inlet 112 and a first outlet 113 formed therein, which communicate with the first receiving space 111. The first inlet 112 is located at a lower portion of the first receiving space 111 so as to be located below a water surface of the first aqueous solution 115. The first outlet 113 is located at an upper portion of the first receiving space 111 so as to be located above a water surface of the first aqueous solution 115. Through the first inlet 112, nitrogen oxides (NOx) or sulfur oxides (SOx), which are used as fuel during the reaction, are introduced into the first accommodating space 111, and, when necessary, the first aqueous solution 115 may also be introduced. Through the first outlet 113, hydrogen (H2) generated during the reaction is discharged to the outside. Although not shown, the inlet 112 and the outlet 113 may be selectively opened and closed at appropriate timing by a valve or the like at the time of reaction. In the cathode portion 110, an elution reaction of nitrogen oxide (NOx) or sulfur oxide (SOx) occurs in the course of the reaction.

The anode part 150 has a second aqueous solution 155 and an anode 158, wherein the second aqueous solution 155 is contained in the second containing space 151, and at least a portion of the anode 158 is immersed in the second aqueous solution 155.

The second aqueous solution 155 may use a high concentration alkali solution, for example, 1M NaOH or 6M NaOH may be used.

The anode 158 is an electrode of a metal material constituting an electric circuit, and in this embodiment, zinc (Zn) or aluminum (Al) is explained as being used as the anode 158.

In addition, an alloy containing zinc or aluminum may also be used for the anode 158.

Now, the reaction process of the exhaust gas purification system 100a described above in terms of configuration will be described in detail. Fig. 1 also shows the reaction process of the exhaust gas purification system 100 a. Referring to fig. 1, nitrogen oxide (NOx) or sulfur oxide (SOx) is injected into a first aqueous solution 115 through an inlet 112, and in a cathode portion 110, a chemical elution reaction of nitrogen oxide (NOx) or sulfur oxide (SOx) as in the following [ reaction formula 1] and [ reaction formula 2] is performed.

[ reaction formula 1]

NOx+H₂O→2HNO₃(aq)

[ reaction formula 2]

SOx+H₂O→H₂SO₄(aq)

That is, in the cathode portion 110, nitrogen oxide (NOx) or sulfur oxide (SOx) supplied to the cathode portion 110 and water (H) of the first aqueous solution 115₂O) to nitric acid (HNO) by spontaneous chemical reaction₃) Or sulfuric acid (H)₂SO₄). Nitric acid (HNO) produced as described above₃) Or sulfuric acid (H)₂SO₄) Generation of hydrogen ions (H) by spontaneous reaction⁺) And salts (NO)₃ ^-、HSO₄ ^-、SO₄ ^2-)。

In addition, in the cathode portion 110, an electric reaction as in the following [ reaction formula 3] occurs.

[ reaction formula 3]

2H⁺(aq)+2e^-→H₂(g)

That is, in the cathode portion 110, hydrogen cations (H)⁺) Receiving electrons (e)^-) To generate hydrogen (H)₂) A gas. Hydrogen (H) produced₂) Gas passing throughThe first outlet 113 is discharged to the outside.

At the same time, a complex hydrogen evolution reaction such as the following [ reaction formula 4] or [ reaction formula 5] occurs in the cathode portion 110.

[ reaction formula 4]

2H₂O(l)+2NOx(g)+2e^-→H₂(g)+2NO₃ ^-(aq)

[ reaction formula 5]

2H₂O(l)+2SOx(g)+2e^-→H₂(g)+2HSO₃ ^-(aq)

In the anode portion 150, when the anode 158 is zinc (Zn), an oxidation reaction proceeds as in the following [ reaction formula 6 ].

[ reaction formula 6]

Zn+4OH^-→Zn(OH)₄ ^2-+2e

Zn(OH)₄ ^2-→ZnO+H₂O+2OH^-

Finally, in the case where the anode 158 is zinc (Zn), the overall reaction formula occurring during the reaction is as the following [ equation 7] or [ equation 8 ].

[ reaction formula 7]

Zn+2NaOH+2HNO₃(aq)→ZnO+H₂O+H₂+2NaNO₃(aq)

[ reaction formula 8]

Zn+2NaOH+H₂SO₄(aq)→ZnO+H₂O+H₂+Na₂SO₄(aq)

If the anode 158 is aluminum (Al), the anode 150 undergoes an oxidation reaction as shown in the following [ reaction formula 9 ].

[ reaction formula 9]

Al+3OH^-→Al(OH)₃+3e^-

Finally, in the case where the anode 158 is aluminum (Al), the overall reaction formula occurring during the reaction is as the following [ equation 10] or [ equation 11 ].

[ reaction formula 10]

2Al+6NaOH+6HNO₃(aq)→2Al(OH)₃+3H₂+6NaNO₃(aq)

[ reaction formula 11]

2Al+6NaOH+3H₂SO₄(aq)→2Al(OH)₃+3H₂+3Na₂SO₄(aq)

As a result, from [ reaction formula 7]][ reaction formula 8]][ reaction formula 10]]And [ reaction formula 11]It is understood that, during the reaction, hydrogen ions generated from nitrogen oxides (NOx) or sulfur oxides (SOx) eluted from the first aqueous solution 115 receive electrons from the cathode 118 and are reduced to hydrogen gas, and are discharged through the first outlet 113, and the metal anode 158 is in the form of an oxide. As the reaction proceeds, Nitrate (NO) is formed in the first aqueous solution 115₃ ^-) Or sulfates (HSO)₄ ^-Or SO₄ ^2-) The aqueous solution contains sodium ions (Na)⁺) For example, in the case where the aqueous solution is sodium hydroxide (NaOH), in order to balance the ions, the sodium ions are diffused so that sodium nitrate (NaNO) is generated₃) Sodium hydrogen sulfate (NaHSO)₄) Or sodium sulfate (Na)₂HSO₄) The ions are present in the form of an aqueous solution. If it is filtered, NOx or SOx contained in the exhaust gas as a pollutant can be removed.

The connection portion 190 connecting the cathode portion 110 and the anode portion 150 of the exhaust gas purification system 100b according to one embodiment of the present technology is provided between the first accommodation space 111 and the second accommodation space 151, and is an ion transport member 192 having a porous structure that blocks movement of the first aqueous solution 115 and the second aqueous solution 155 and allows ion substances dissolved in the aqueous solutions to pass therethrough.

The cathode portion 110 has a first inlet 112, a first outlet 113, and a first connection port 114 formed therein, which communicate with the first accommodation space 111. The first connection port 114 is located below the water level of the first aqueous solution 115, and the connection 190 is connected to the first connection port 114.

The anode 150 is formed with a second connection port 154 communicating with the second accommodation space 151. The second connection port 154 is located below the water surface of the second aqueous solution 155, and the connection 190 is connected to the second connection port 154.

The connection part 190 according to this embodiment has a connection passage 191 and an ion transport member 192, wherein the connection passage 191 connects the cathode part 110 and the anode part 150 using a porous ion transport member, and the ion transport member 192 is disposed inside the connection passage 191.

The connection channel 191 extends between the first connection port 114 formed at the cathode portion 110 and the second connection port 154 formed at the anode portion 150, thereby communicating the first accommodation space 111 of the cathode portion 110 and the second accommodation space 151 of the anode portion 150. The ion transmission member 192 is disposed inside the connection passage 191.

The ion transmission member 192 has a substantially disk shape, and is provided in a form of blocking the inside of the connection passage 191. The ion transport member 192 is composed of a porous structure that allows movement of ions between the cathode portion 110 and the anode portion 150 while blocking movement of the aqueous solutions 115, 155. In this embodiment, a case where the material of the ion transport member is glass is described, but the present technology is not limited thereto, and other materials of a porous structure may be used, which also falls within the scope of the present technology. In this embodiment, the ion transport member 192 may use porous glass having a pore size of 40 to 90 microns on a scale corresponding to G2, 15 to 40 microns on a scale corresponding to G3, 5 to 15 microns on a scale corresponding to G4, 1 to 2 microns on a scale corresponding to G5. The ion transport member 192 only transports ions, thereby eliminating ion imbalances that occur during the reaction process.

Fig. 2 shows the configuration of an exhaust gas purification system 100b according to another embodiment of the present technology. Referring to fig. 2, an exhaust gas purification system 100b according to an embodiment of the present technology includes a reaction space 161, a cathode 118, and an anode 158 of a metallic material, wherein the reaction space 161 contains an aqueous solution 161, and in the reaction space 161, at least a portion of the cathode 118 is immersed in the aqueous solution 161, and at least a portion of the anode 158 is immersed in the aqueous solution 161.

The reaction vessel 160 provides a reaction space 161 containing an aqueous solution 162 therein and housing the cathode 118 and the anode 158. The reaction vessel 160 has a first inlet 112 and a first outlet 113 formed therein, which communicate with the reaction space 161. The first inlet 112 is located at a lower portion of the reaction space 161 so as to be located below a water surface of the aqueous solution 162. The first outlet 113 is located at an upper portion of the reaction space 161 so as to be located above a water surface of the aqueous solution 162. Through the first inlet 112, nitrogen oxides (NOx) or sulfur oxides (SOx) used as fuel during the reaction may be introduced into the reaction space 161 and, if necessary, the aqueous solution 162 may also be introduced. Through the first outlet 113, hydrogen (H2) generated during the reaction is discharged to the outside.

Although not shown, the first inlet 112 and the first outlet 113 may be selectively opened and closed at appropriate timing by a valve or the like at the time of reaction. The first connection port 114 is located below the water level of the first aqueous solution 115, and the connection 190 is connected to the first connection port 114. In the reaction space 161, an elution reaction of nitrogen oxides (NOx) or sulfur oxides (SOx) occurs during the reaction.

An aqueous solution 162 is held in the reaction space 161, and at least a portion of the cathode 118 and at least a portion of the anode 158 are immersed in the aqueous solution 162. In this embodiment, a case where an alkaline solution or seawater is used as the aqueous solution 162 will be described. The aqueous solution 162 exhibits weak acidity during the reaction due to the carbon dioxide gas introduced through the first inlet 112.

At least a portion of the cathode 118 is immersed in the aqueous solution 162 in the reaction space 161. The cathode 118 is positioned relatively close to the first inlet 112 in the reaction space 161 compared to the anode 158. The cathode 118 is an electrode for forming a circuit, which may be carbon paper, carbon fiber, carbon felt, carbon cloth, metal foam, metal thin film, or a combination thereof, and a platinum catalyst may also be used. In the case of the catalyst, in addition to the platinum catalyst, a carbon-based catalyst, a carbon-metal-based composite catalyst, a perovskite oxide catalyst, and the like are included, and all other catalysts that can be generally used as an oxygen evolution reaction (HER) catalyst are included. Upon reaction, a reduction reaction occurs at the cathode 118, and hydrogen gas may be generated accordingly.

At least a portion of the anode 158 is immersed in an aqueous solution 162 in a reaction space 161. The anode 158 is positioned relatively far from the first inlet 112 in the reaction space 161 as compared to the cathode 118. The anode 158 is an electrode of a metal material constituting a circuit, and in this embodiment, a case where vanadium (V), chromium (Cr), manganese (Mn), iron (Fe), cobalt (Co), nickel (Ni), copper (Cu), aluminum (Al), or zinc (Zn) is used for the anode 158 will be described. During the reaction, an oxidation reaction occurs at the anode 158 according to a weakly acidic environment.

The reaction process of the above exhaust gas purification system 100b is the same as the processes of [ reaction formula 1] to [ reaction formula 11] described above.

Fig. 3 shows the configuration of an exhaust gas purification system 100c according to still another embodiment of the present technology. Referring to fig. 3, an exhaust gas purification system 100 according to an embodiment of the present technology includes: a cathode portion 110c including a first receiving space 111c, an aqueous electrolyte 115c, and a cathode 118c, at least a portion of the cathode 118c being immersed in the aqueous electrolyte 115 c; an anode portion 150c including a second receiving space 151c, an electrolyte 155c, and a metal anode 158c, at least a portion of the anode 158c being immersed in the electrolyte 155 c; and a solid electrolyte 190c disposed between the cathode part 110c and the anode part 150c to selectively pass metal ions ionized by the metal.

The exhaust gas purification system 100 according to one embodiment of the present technology generates electric power and hydrogen (H) as an environmentally friendly fuel by using nitrogen oxides (NOx) or sulfur oxides (SOx) included in exhaust gas as a raw material through an electrochemical reaction as pollutants₂)。

The cathode portion 110c has an aqueous electrolyte 115c and a cathode 118c, wherein the aqueous electrolyte 115c is accommodated in a first accommodation space 111c partitioned by a solid electrolyte 190c at one side, and at least a portion of the cathode 118c is immersed in the aqueous electrolyte 115 c.

The aqueous electrolyte 115c may be a neutral aqueous electrolyte solution, an alkaline aqueous electrolyte solution, an electrolyte containing chlorine ions, seawater, tap water, distilled water, or the like.

The cathode 118c is an electrode for forming a circuit, which may be carbon paper, carbon fiber, carbon felt, carbon cloth, metal foam, metal thin film, or a combination thereof, and a platinum catalyst may also be used. In the case of the catalyst, a carbon-based catalyst, a carbon-metal-based composite catalyst, a perovskite oxide catalyst, or the like may be used in addition to the platinum catalyst, and all other catalysts are also included.

The cathode portion 110c has a first inlet 112c and a first outlet 113c formed therein, which communicate with the first receiving space 111 c. The first inlet 112c is located at a lower portion of the first receiving space 111c so as to be located below a water surface of the aqueous electrolyte 115 c. The first outlet 113c is located at an upper portion of the first receiving space 111c so as to be located above a water surface of the aqueous electrolyte 115 c. Through the first inlet 112c, nitrogen oxides (NOx) or sulfur oxides (SOx) used as fuel during the reaction can be introduced into the first accommodating space 111c, and when necessary, the aqueous electrolyte 115c can also be introduced. Hydrogen (H2) generated during the reaction is discharged to the outside through the first outlet 113 c. Although not shown, the inlet 112c and the outlet 113c may be selectively opened and closed at appropriate timing by a valve or the like at the time of reaction. In the cathode portion 110c, an elution reaction of nitrogen oxide (NOx) or sulfur oxide (SOx) occurs in the course of the reaction.

The anode part 150c has an electrolyte 155c and an anode (anode)158c, wherein the electrolyte 155c is contained in a second containing space 151c partitioned at one side by a solid electrolyte 190c, and at least a portion of the anode 158c is immersed in the electrolyte 155 c.

The electrolyte 155c may be an organic electrolyte, but is not limited thereto, and NaClO (propylene carbonate, PC), Ethylene Carbonate (EC), and dimethyl carbonate (DMC) may be used alone or in combination₄Or NaPF₆Dissolved therein for use.

The anode 158c is an electrode of a metal material constituting an electric circuit, which is formed of sodium metal or a substance including sodium metal, so that sodium ions moved from the cathode portion 110c are reduced and stored as sodium metal and can oxidize the stored sodium metal. Although not shown, an anode active material layer may be formed on the surface of the anode 158 c. In the present embodiment, a case where the anode 158c is a substance including sodium metal is described, but other metals (for example, Li, Mg, and the like) may be used in addition to sodium metal.

The solid electrolyte 190c is disposed between the cathode portion 110c and the anode portion 150c in the form of a wall such that both sides are in contact with the aqueous electrolyte 111c accommodated in the first accommodation space 116 of the cathode portion 110c and the electrolyte 151c accommodated in the second accommodation space 126 of the anode portion 150c, respectively. The solid electrolyte 190c selectively passes only sodium ions between the cathode portion 110c and the anode portion 150 c. In this embodiment, it will be described that it consists of Na₃Zr₂Si₂PO₁₂Which is a sodium super ion conductor (NASICON), is formed so as to efficiently transmit sodium ions.

Now, the reaction process of the exhaust gas purification system 100 described above in terms of configuration will be described in detail. Fig. 3 also shows the reaction process of the exhaust gas purification system 100. Referring to fig. 3, nitrogen oxide (NOx) or sulfur oxide (SOx) is injected into the aqueous electrolyte 115c through the inlet 112c, and a chemical elution reaction of nitrogen oxide (NOx) or sulfur oxide (SOx) as in the following [ reaction formula 1] and [ reaction formula 2] is performed in the cathode portion 110 c.

[ reaction formula 1]

NOx+H₂O→2HNO₃(aq)

[ reaction formula 2]

SOx+H₂O→H₂SO₄(aq)

That is, in the cathode portion 110c, nitrogen oxides (NOx) or sulfur oxides (SOx) supplied to the cathode portion 110c and water (H) of the aqueous electrolyte 115c₂O) to nitric acid (HNO) by spontaneous chemical reaction₃) Or sulfuric acid (H)₂SO₄). Nitric acid (HNO) produced as described above₃) Or sulfuric acid (H)₂SO₄) Generation of hydrogen ions (H) by spontaneous reaction⁺) And salts (NO)₃ ^-、HSO₄ ^-、SO₄ ^2-)。

In addition, due to the nitric acid (HNO) generated₃) Supply of hydrogen ions (H)⁺) Therefore, the following [ reaction formula 12] proceeds in the cathode portion 110c]Electrical reaction of (3).

[ reaction formula 12]

2Na(s)+2HNO₃(aq)→H₂(g)+2NaNO₃(aq) E^o＝2.71V

Due to sulfuric acid (H) formed₂SO₄) Hydrogen ions (H) are also supplied⁺) Therefore, the following [ reaction formula 13] proceeds in the cathode portion 110c]Electrical reaction of (3).

[ reaction formula 13]

2Na(s)+H₂SO₄(aq)→H₂(g)+Na₂SO₄(aq) E^o＝2.71V

That is, in the cathode portion 110c, hydrogen cations (H)⁺) Receiving electrons (e)^-) To generate hydrogen (H)₂) A gas. Hydrogen (H) produced₂) The gas is discharged to the outside through the first outlet 113 c.

In the anode portion 150c, an electric reaction proceeds as in the following [ reaction formula 14 ].

[ reaction formula 14]

2Na(s)→2Na⁺(aq)+2e^-

That is, in the anode portion 150c, sodium (Na) is decomposed into sodium cations (Na)⁺) And electron (e)^-) And sodium cation (Na)⁺) Is transported to the cathode portion 110c through the solid electrolyte 190 c.

Salt (HCO) remaining in the aqueous electrolyte 115c₃ ^-) And sodium cations (Na) that move from the anode portion 150c to the cathode portion 110c⁺) The electrons equilibrate and sodium nitrate (NaHCO) is formed₃) Sodium hydrogen sulfate (NaHSO)₄) Or sodium sulfate (Na)₂SO₄) And hydrogen (H)₂). Sodium nitrate (NaHCO) formed₃) Sodium hydrogen sulfate (NaHSO)₄) Or sodium sulfate (Na)₂SO₄) In the form of an aqueous solution, the aqueous electrolyte 111c, and if it is filtered, NOx or SOx, which are pollutants included in the exhaust gas, can be removed. Hydrogen (H) produced₂) Is discharged to the outside through the first outlet 113 c.

As a result, as can be seen from the above-mentioned [ reaction formula 1], [ reaction formula 2], [ reaction formula 12], [ reaction formula 13] and [ reaction formula 14], during the reaction, hydrogen ions generated from nitrogen oxides (NOx) or sulfur oxides (SOx) eluted from the aqueous electrolyte 115c receive electrons from the cathode 118 and are reduced to hydrogen gas, and are discharged through the first outlet 113.

Fig. 4 shows the configuration of an exhaust gas purification system according to an embodiment of the present technology. Referring to fig. 4, an exhaust gas purification system 100d according to an embodiment of the present technology includes: a reaction vessel 160d forming a reaction space 161 d; an electrolyte aqueous solution 162d which is contained in the above-mentioned reaction space 161d and includes chloride anions; a cathode 118d at least a part of which is immersed in the aqueous electrolyte solution 162d in the reaction space 161 d; an anode 158d at least a part of which is immersed in the aqueous electrolyte solution 162d in the reaction space 161 d; and a power source 170d electrically connected to the cathode 118d and the anode 158 d.

The reaction vessel 160d provides a reaction space 161d containing an aqueous electrolyte solution 162d therein and accommodating the cathode 118d and the anode 158 d. The reaction vessel 160d may have an inlet 112d formed therein, which communicates with the reaction space 161 d. The inlet 112d is located at a lower portion of the reaction space 161d so as to be located below the water surface of the electrolyte aqueous solution 162 d. Through the inlet 112d, nitrogen oxides (NOx) or sulfur oxides (SOx) used as fuel during the reaction can be introduced into the reaction space 161d, and when necessary, the aqueous electrolyte solution 162d can also be introduced.

Further, the reaction vessel may have a hydrogen gas discharge portion 113d that discharges the generated hydrogen gas. Preferably, the hydrogen gas discharge part 113d is located at an upper portion of the cathode 118d of the reaction space 161d so as to be located above the water surface of the electrolyte aqueous solution 162 d. Hydrogen (H) produced during the reaction₂) And discharged to the outside through the hydrogen gas discharge part 113 d.

Although not shown, the inlet portion 112d and the hydrogen gas discharge portion 113d may be selectively opened and closed at an appropriate timing by a valve or the like at the time of reaction.

An aqueous electrolyte solution 162d is contained in the reaction space 161d, and at least a portion of the cathode 118d and at least a portion of the anode 158d are immersed in the aqueous electrolyte solution 162 d. The electrolyte aqueous solution 162d includes chloride ions (Cl) like seawater or brine^-) In the embodiment ofIn the description, the electrolyte aqueous solution 162d is a sodium chloride (NaCl) aqueous solution. Thus, the aqueous electrolyte solution 162d includes sodium cations (Na)⁺) And chloride anion (Cl)^-). The aqueous electrolyte solution 162d exhibits weak acidity during the reaction due to nitrogen oxides or sulfur oxides flowing in through the inlet 112 d.

At least a portion of the cathode 118d is immersed in the aqueous electrolyte solution 162d in the reaction space 161 d. The cathode 118d is positioned relatively close to the inlet 112d in the reaction space 161 as compared to the anode 158 d. The cathode 118d is electrically connected to the negative pole of the power source 170d, thereby receiving electrons from the power source 170 d. The cathode 118d is an electrode for forming a circuit, which may be carbon paper, carbon fiber, carbon felt, carbon cloth, metal foam, metal thin film, or a combination thereof, and a platinum catalyst may also be used. In the case of the catalyst, in addition to the platinum catalyst, all other catalysts that can be generally used as a Hydrogen Evolution Reaction (HER) catalyst, such as a carbon-based catalyst, a carbon-metal-based composite catalyst, a perovskite oxide catalyst, and the like, are included. At the time of reaction, a reduction reaction occurs at the cathode 118d, and hydrogen gas may be thus generated.

At least a portion of the anode 158d is immersed in the aqueous solution 162d in the reaction space 161 d. The anode 158d is electrically connected to the positive electrode of the power source 170d, thereby supplying electrons to the power source 170 d. In this embodiment, a case where vanadium (V), chromium (Cr), manganese (Mn), iron (Fe), cobalt (Co), nickel (Ni), copper (Cu), aluminum (Al), or zinc (Zn) is used for the anode 158d will be described.

In the case of the catalyst, in addition to the platinum catalyst, a carbon-based catalyst, a carbon-metal-based composite catalyst, a perovskite oxide catalyst, and the like are included, and all other catalysts that can be generally used as a catalyst for a combustion generating reaction are included. At the anode 158d, a Chlorine Evolution Reaction (CER) caused by an oxidation Reaction occurs.

The power supply 170d supplies electric power to the exhaust gas purification system 100 d. The positive electrode of the power source 170d is electrically connected to the anode 158d of the exhaust gas purification system 100d, and the negative electrode of the power source 170d is electrically connected to the cathode 118d of the exhaust gas purification system 100 d. As power source 170d, any type of power source that can supply electric energy, including renewable energy sources such as solar cells and wind power generation, can be used. The exhaust gas purification system 100d can remove nitrogen oxides or sulfur oxides, which are substances generating fine dust, by generating hydrogen gas and chlorine gas using carbon dioxide as a raw material using electric power supplied from the power source 170 d.

Now, the reaction process of the exhaust gas purification system 100d described above in terms of configuration will be described in detail. Fig. 4 also shows the reaction process of the exhaust gas purification system 100 d. Referring to fig. 4, nitrogen oxides (NOx) or sulfur oxides (SOx) are injected into the electrolyte aqueous solution 162d of the reaction space 161d through the inlet 112d, and a chemical elution reaction as in the following [ reaction formula 1] or [ reaction formula 2] occurs.

[ reaction formula 1]

NOx+H₂O→HNO₃(aq)

[ reaction formula 2]

SOx+H₂O→H₂SO₄(aq)

That is, nitrogen oxides (NOx) or sulfur oxides (SOx) of the aqueous electrolyte solution 162d supplied into the reaction space 161d and water (H) in the aqueous electrolyte solution 162d₂O) to form nitric acid (HNO)₃) Or sulfuric acid (H)₂SO₄). Nitric acid (HNO) produced as described above₃) Or sulfuric acid (H)₂SO₄) Spontaneously generate hydrogen ions (H)⁺) And salts (NO)₃ ^-、HSO₄ ^-、SO₄ ^2-)。

Further, an electric reaction as shown in the following [ reaction formula 3] occurs at the cathode 118 d.

[ reaction formula 3]

2H⁺(aq)+2e^-→H₂(g)

That is, the cathode 118d is oriented towards hydrogen cations (H)⁺) Supply of electrons (e)^-) To generate hydrogen (H)₂) A gas. Hydrogen (H) formed₂) The gas is discharged to the outside through the hydrogen gas discharge part 113 d.

At the same time, a complex hydrogen evolution reaction such as the following [ reaction formula 4] or [ reaction formula 5] occurs at the cathode 118 d.

[ reaction formula 4]

2H₂O(l)+2NOx(g)+2e^-→H₂(g)+2NO₃ ^-(aq)

[ reaction formula 5]

2H₂O(l)+2SOx(g)+2e^-→H₂(g)+2HSO₃ ^-(aq)

Further, a chlorine generating reaction [ equation 15] as follows occurs at the anode 158 d.

[ reaction formula 15]

2Cl^-(aq)→Cl₂(g)+2e^-(E⁰＝1.36V vs.SHE)

Finally, the final overall reaction formula is as follows [ equation 16] or [ equation 17], depending on whether the gas supplied to the aqueous electrolyte solution 162d contains nitrogen oxide (NOx) or sulfur oxide (SOx).

[ reaction formula 16]

2NaCl(aq)+2HNO₃(aq)→H₂+Cl₂+2NaNO₃(aq) E^o＝1.36V

[ reaction formula 17]

2NaCl(aq)+H₂SO₄(aq)→H₂+Cl₂+Na₂SO₄(aq) E^o＝1.36V

From [ reaction formula 16]]And [ reaction formula 17]It is known that hydrogen ions (H) are generated after the electrolysis⁺) And disappears, so that the pH of the aqueous electrolyte solution 162d increases to become alkaline, so that nitrogen oxides (NOx) or sulfur oxides (SOx) introduced through the inlet can be continuously dissolved. The electrolyte aqueous solution 162d, which is initially an aqueous solution of sodium chloride (NaCl), gradually changes to sodium nitrate (NaNO) as the reaction proceeds₃) Aqueous solution or sodium sulfate (Na)₂SO₄) An aqueous solution.

In the present embodiment, although the case where the aqueous electrolyte solution 162d uses an aqueous sodium chloride (NaCl) solution is described, an aqueous potassium chloride (KCl) solution or calcium chloride (CaCl) solution may be used₂) An aqueous solution or the like including other cations is substituted for the aqueous sodium chloride solution, and in this case, a nitrate or sulfate corresponding thereto may be generated.

The exhaust gas purification system 100d may adjust the amount of chlorine gas generated at the anode so that the amount of nitrogen oxide or sulfur oxide dissolved in the aqueous electrolyte solution 162d is maintained at a predetermined value or more, thereby maintaining the pH of the aqueous electrolyte solution 162d at a predetermined value or more.

In addition, when using chloride-free (Cl)^-) When the solution (2) is used as the aqueous electrolyte solution 162d, the following reaction [ equation 17] is carried out at the anode 158d]The oxygen evolution reaction.

[ reaction formula 17]

4OH^-→O₂+2H₂O+4e^-

Thus, the pH of the electrolyte aqueous solution 162d does not change, and the nitrogen oxide or the sulfur oxide does not further dissolve.

As a result, a reaction system represented by the following formula 1]To [ reaction formula 5]]And [ reaction formula 15]To [ reaction formula 16]]It is understood that, during the reaction, hydrogen ions generated from nitrogen oxides (NOx) or sulfur oxides (SOx) eluted from the electrolyte aqueous solution 162d receive electrons from the cathode 118d, are reduced to hydrogen gas, and are discharged through the hydrogen gas discharge portion 113 d. As the reaction proceeds, Nitrate (NO) is formed in the aqueous electrolyte solution 115₃ ^-) Or sulfates (HSO)₄ ^-Or SO₄ ^2-) And the aqueous solution contains sodium ions (Na)⁺) For example, in the case where the aqueous solution is sodium hydroxide (NaOH), in order to balance the ions, the sodium ions are diffused so that sodium nitrate (NaNO) is generated₃) Sodium hydrogen sulfate (NaHSO)₄) Or sodium sulfate (Na)₂SO₄) The ions are present in the form of an aqueous solution. If it is filtered, NOx or SOx contained in the exhaust gas as a pollutant can be removed.

In addition, the exhaust gas purification systems 100a, 100b, and 100c according to one embodiment of the present technology may not only treat sodium nitrate (NaNO) generated after the reaction₃) Sodium hydrogen sulfate (NaHSO)₄) Or sodium sulfate (Na)₂HSO₄) Filtering, drying or precipitating with precipitant to remove fine dust (carbon compound, organic substance, inorganic substance, metal or other substances) 0.01-100 μm except NOx or SOx contained in the exhaust gasSalts thereof, etc.) are directly filtered and removed from the exhaust gas.

The fine dust can be slurried (slury) or suspended by adding water to an aqueous solution to form a precipitate, and the precipitate, slurry or suspended matter thus formed can be removed by a method such as separation, filtration, coagulation or discharge.

Although the present technology is explained by the above embodiments, the present technology is not limited thereto. The above-described embodiments may be modified or changed without departing from the spirit and scope of the present technology, and those of ordinary skill in the art will understand that such modifications and changes also belong to the present technology.

Industrial applicability

The carbon dioxide utilizing device according to the present technology can generate electricity, hydrogen and bicarbonate ions by utilizing carbon dioxide through spontaneous electrochemical reactions without an external power source, and thus can be combined with a fuel cell system or other devices to remove carbon dioxide as greenhouse gas discharged and generate hydrogen as a clean energy and supply it to a fuel cell, thereby realizing an environmentally-friendly combined cycle power generating system that does not generate carbon dioxide. In addition, it can be applied to ships or submarines, thus being effectively used for removing carbon dioxide generated during operation or generating electricity.