KR20230027582A - Catalyst-Electrode Structure and Electrochemical Reactor using the same and System of utilizing Carbon Dioxide using the same - Google Patents

Abstract

The present invention provides a catalyst-electrode structure, an electrochemical reaction device using the same, and a carbon dioxide utilization system, wherein the catalyst-electrode structure includes: an electrode body made of a conductive material; an inlet comprising a hole penetrating the electrode body at one side of the electrode body; an outlet comprising a hole penetrating the electrode body on the other side of the electrode body; a passage comprising a groove provided on one surface of the electrode body and connecting a gap between the inlet and the outlet; and a catalyst filled in the passage.

Description

Catalyst-Electrode Structure and Electrochemical Reactor using the same and System of utilizing Carbon Dioxide using the same}

The present invention relates to an electrochemical reaction device for reducing carbon dioxide, and more particularly, to a catalyst-electrode structure that can be used in an electrochemical reaction device.

The global carbon cycle is being thrown out of balance by the increase in carbon dioxide in the atmosphere. The increase in carbon dioxide in the atmosphere is mainly caused by an increase in carbon dioxide emissions from factories, power plants, or automobiles.

Therefore, in order to remove carbon dioxide in the atmosphere, research on the electrochemical reduction of carbon dioxide and the production of useful syngas has been steadily conducted.

So far, electrochemical reaction devices capable of producing various syngas by reducing carbon dioxide have been proposed, but conversion efficiency of syngas is still low.

The present invention has been devised in view of the above-mentioned conventional situation, and an object of the present invention is to provide a catalyst-electrode structure capable of improving the conversion efficiency of carbon dioxide, an electrochemical reaction device using the same, and a carbon dioxide utilization system.

In order to achieve the above object, the present invention is an electrode body made of a conductive material; an inlet made of a hole penetrating the electrode body at one side of the electrode body; an outlet formed of a hole penetrating the electrode body on the other side of the electrode body; a passage made of a groove provided on one surface of the electrode body and connecting between the inlet and the outlet; and a catalyst filled in the passage to provide a catalyst-electrode structure.

The catalyst may fill the entire inside of the passage and contact both the lower surface and the side surface of the passage.

The height of the top of the catalyst may be the same as that of one side of the electrode body.

A blocking wall for preventing the catalyst from flowing into the inlet or the outlet may be further provided.

The blocking wall may include a first blocking wall provided on a boundary surface between the inlet and the flow path and a second blocking wall provided on a boundary surface between the outlet and the flow path.

Each of the first blocking wall and the second blocking wall may include a plurality of holes, and a diameter of the plurality of holes may be smaller than a diameter of the catalyst.

The passage may include at least one of a curved straight structure, a curved curved structure, and a mesh structure.

It is made of a groove provided on one surface of the electrode body, and further includes a sealing groove provided on the outside of the inlet, the outlet, and the flow path, and the depth of the groove of the flow path is the depth of the groove of the sealing groove. can be made deeper.

The present invention also provides a reduction electrode and an oxidation electrode facing each other; a separation membrane provided between the reduction electrode and the oxidation electrode; a reducing material input/output unit connected to the reduction electrode; and an oxide input/output unit connected to the oxidation electrode, wherein at least one of the reduction electrode and the oxidation electrode provides an electrochemical reaction device comprising the above-described catalyst-electrode structure.

The separator may contact one surface of the catalyst and the electrode body while overlapping the inlet, outlet, and flow path provided in the electrode body.

A tertiary amine aqueous solution containing HCO ₃ ^- may be introduced into the cathode to generate carbon monoxide and hydrogen.

The separator may be formed of a bipolar membrane, and the bipolar membrane may be provided so that OH ⁻ moves to the oxidation electrode, H ⁺ moves to the reduction electrode, and HCO ₃ ⁻ does not move to the oxidation electrode.

The present invention also, a carbon dioxide capture device for capturing carbon dioxide; an electrochemical reaction device for producing synthesis gas by reducing the carbon dioxide collected by the carbon dioxide collecting device; a hydrogen carrier manufacturing device for manufacturing a hydrogen carrier material using the syngas produced in the electrochemical reactor; a dehydrogenation device for producing hydrogen from the hydrogen carrier material produced in the hydrogen transport production device; and a hydrogen utilization device utilizing hydrogen produced by the dehydrogenation device, wherein the electrochemical reaction device provides a carbon dioxide utilization system composed of the aforementioned electrochemical reaction device.

According to the present invention as described above, there are the following effects.

According to an embodiment of the present invention, the catalyst-electrode structure constituting the reduction electrode includes an electrode body having a flow path and a catalyst filled in the flow path, so that carbon dioxide contacts the catalyst while passing through the flow path. Since the area can be increased, the conversion efficiency of carbon dioxide can be improved. Similarly, since the catalyst-electrode structure constituting the oxidation electrode includes an electrode body having a flow path and a catalyst filled in the flow path, the contact area with the catalyst may increase while the aqueous electrolyte solution passes through the flow path. As a result, the production rate of oxygen gas can be improved.

According to another embodiment of the present invention, a state in which carbon dioxide is captured in an aqueous amine solution, more specifically, an aqueous amine solution including HCO ₃ ^- is electrochemically Since it is introduced into the reaction device, the cost of the carbon dioxide separation process is saved, the carbon dioxide conversion efficiency is improved, and crossover of carbon dioxide to the counter electrode does not occur.

According to another embodiment of the present invention, since the separator of the electrochemical reaction device is formed of a bipolar membrane, the efficiency of generating hydrogen at the cathode and the efficiency of generating oxygen at the anode can be improved.

According to another embodiment of the present invention, by producing hydrogen from the dehydrogenation device and supplying it to the hydrogen utilization device, as well as producing carbon dioxide from the dehydrogenation device and supplying it to the carbon dioxide capture device, there is an advantage of recycling carbon dioxide by circulating it.

1 is a schematic diagram of an electrochemical reactor according to an embodiment of the present invention.
2 is a plan view of a catalyst-electrode structure according to an embodiment of the present invention.
3 is a cross-sectional view along line AB of FIG. 2 .
4 is a cross-sectional view of the CD line of FIG. 2;
5 is a cross-sectional view showing a coupling structure of a reduction electrode, an oxidation electrode, and a separator according to an embodiment of the present invention.
6 is a plan view of a catalyst-electrode structure according to another embodiment of the present invention.
7 is a schematic diagram of an electrochemical reactor according to another embodiment of the present invention.
8 is a schematic diagram of a carbon dioxide utilization system according to an embodiment of the present invention.

Advantages and features of the present invention, and methods of achieving them, will become clear with reference to the detailed description of the following embodiments taken in conjunction with the accompanying drawings. However, the present invention is not limited to the embodiments disclosed below, but will be implemented in a variety of different forms, and only the present embodiments make the disclosure of the present invention complete, and common knowledge in the art to which the present invention belongs. It is provided to fully inform the holder of the scope of the invention, and the present invention is only defined by the scope of the claims.

The shapes, sizes, ratios, angles, numbers, etc. disclosed in the drawings for explaining the embodiments of the present invention are illustrative, so the present invention is not limited to the details shown. Like reference numbers designate like elements throughout the specification. In addition, in describing the present invention, if it is determined that a detailed description of related known technologies may unnecessarily obscure the subject matter of the present invention, the detailed description will be omitted. When 'includes', 'has', 'consists of', etc. mentioned in this specification is used, other parts may be added unless 'only' is used. In the case where a component is expressed in the singular, the case including the plural is included unless otherwise explicitly stated.

In interpreting the components, even if there is no separate explicit description, it is interpreted as including the error range.

In the case of a description of a positional relationship, for example, 'on top of', 'on top of', 'at the bottom of', 'next to', etc. Or, unless 'directly' is used, one or more other parts may be located between the two parts.

In the case of a description of a temporal relationship, for example, 'immediately' or 'directly' when a temporal precedence relationship is described in terms of 'after', 'following', 'next to', 'before', etc. It can also include non-continuous cases unless is used.

Although first, second, etc. are used to describe various components, these components are not limited by these terms. These terms are only used to distinguish one component from another. Therefore, the first component mentioned below may also be the second component within the technical spirit of the present invention.

Each feature of the various embodiments of the present invention can be partially or entirely combined or combined with each other, technically various interlocking and driving are possible, and each embodiment can be implemented independently of each other or can be implemented together in a related relationship. may be

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the drawings.

1 is a schematic diagram of an electrochemical reactor according to an embodiment of the present invention.

As can be seen in FIG. 1, the electrochemical reaction device according to an embodiment of the present invention includes a reduction electrode 10, an oxidation electrode 20, a separator 30, a reducing material input/output unit 40, and an oxide material input/output unit. (50).

The reduction electrode 10 may generate syngas by reducing carbon dioxide supplied from the reducing material input/output unit 40 . The reduction electrode 10 is composed of a catalyst-electrode structure described later, and can generate various syngas such as carbon monoxide, formic acid, or ethylene depending on the type of catalyst.

The oxidation electrode 20 may generate oxygen gas by oxidizing water supplied from the oxidizing input/output unit 50 . The oxidation electrode 20 may also be formed of a catalyst-electrode structure described later.

The separator 30 is provided between the reduction electrode 10 and the oxidation electrode 20 . The separation membrane 30 may be formed of various ion exchange membranes known in the art.

The reducing material input/output unit 40 supplies the reducing material stored in the external first storage device to the inside of the reduction electrode 10 and also supplies the syngas generated from the reduction electrode 10 to the external second storage device. can serve as a sender. To this end, the reducing material input/output unit 40 includes an inlet 41 and an outlet 42. Carbon dioxide enters the reduction electrode 10 through the inlet 41 of the reducing material input/output unit 40, and synthesis gas flows through the reduction electrode 10 through the outlet 42 of the reducing material input/output unit 40. will come out

The oxide material input/output unit 50 supplies oxide material stored in the external third storage device to the inside of the oxidation electrode 20 and oxygen gas generated from the oxidation electrode 20 to the external fourth storage device. can serve as a sender. To this end, the oxidizing input/output unit 50 includes an inlet 51 and an outlet 52. An aqueous electrolyte solution enters the oxidation electrode 20 through the inlet 51 of the oxide input/output unit 50, and oxygen gas flows into the oxidation electrode 20 from the outlet 52 of the oxide input/output unit 50. ) come out.

The reducing material input/output unit 40 and the oxide material input/output unit 50 may function as current collectors of an electrochemical reaction device.

In this specification, a reducing material means a material to be reduced, and an oxidizing material means a material to be oxidized.

2 is a plan view of a catalyst-electrode structure according to an embodiment of the present invention, FIG. 3 is a cross-sectional view taken along the line A-B of FIG. 2, and FIG. 4 is a cross-sectional view taken along the line C-D of FIG.

Referring to FIG. 2 , a catalyst-electrode structure according to an embodiment of the present invention includes an electrode body 100 and a catalyst 200.

The electrode body 100 may have a predetermined shape, for example, a rectangular plate structure, but is not necessarily limited thereto. The electrode body 100 may be made of a conductive material.

The electrode body 100 is provided with an inlet 110 and an outlet 120. The inlet 110 may be formed on one side of the electrode body 100, for example, near one corner of a rectangular plate, and is formed of a hole penetrating the electrode body 100. The outlet 120 may be formed on the other side of the electrode body 100, for example, near another corner of a rectangular plate, and is formed of a hole penetrating the electrode body 100. As shown, the inlet 110 and the outlet 120 of the electrode body 100 may be formed to face each other at two diagonal corners of the rectangular plate, but are not necessarily limited thereto.

When the catalyst-electrode structure according to an embodiment of the present invention constitutes the reduction electrode 10 of FIG. 1 described above, the inlet 110 of the electrode body 100 is the reducing material entry/exit portion of FIG. 1 described above. 40 communicates with the inlet 41, and the outlet 120 of the electrode body 100 communicates with the outlet 51 of the reducing material inlet/output 40 of FIG. 1 described above. Alternatively, when the catalyst-electrode structure according to an embodiment of the present invention constitutes the anode 20 of FIG. 1 described above, the inlet 110 of the electrode body 100 enters and exits the oxide material of FIG. 1 described above. It communicates with the inlet 51 of the unit 50, and the outlet 120 of the electrode body 100 communicates with the outlet 52 of the oxide input/output unit 50 of FIG. 1 described above.

A flow path 130 is formed between the inlet 110 and the outlet 120 in the electrode body 100 . The passage 130 has a structure of an intaglio groove provided on the first surface 101 of the electrode body 100 while connecting between the inlet 110 and the outlet 120 . Accordingly, the reducing material or oxidizing material entering through the inlet 110 may exit through the outlet 120 while moving along the flow path 130 .

The electrode body 100 has a sealing groove 140 formed outside the inlet 110 , the outlet 120 , and the flow path 130 . The sealing groove 140 has a curved structure corresponding to the hole shape of the inlet 110 and the outlet 120 in the outer region of the inlet 110 and the outlet 120 and has a closed loop structure as a whole. can be made with

The sealing groove 140 has a structure of an intaglio groove provided on the first surface 101 of the body 100. The sealing groove 140 serves to seal between the anode 10 and the cathode 20 facing each other, as shown in FIG. 1 , and a sealing member is inserted into the sealing groove 140 .

The inner region of the sealing groove 140 becomes a reaction region, and thus the separation membrane 30 of FIG. 1 is disposed in the inner region of the sealing groove 140 . The separator 30 may overlap not only the flow path 130 of the body 100 but also the inlet 110 and outlet 120 of the body 100 . The separation membrane 30 may be formed to have a shape corresponding to an inner region of the sealing groove 140 .

In addition, the electrode body 100 includes a first blocking wall 150 and a second blocking wall 160 . The first blocking wall 150 and the second blocking wall 160 are provided to prevent the catalyst 200 from flowing into the inlet 110 or the outlet 120 .

The first blocking wall 150 is provided at a boundary between the inlet 110 and the flow path 130, and the second blocking wall 160 is provided between the outlet 120 and the flow path 130. are available at the border. Therefore, the catalyst 200 filled in the flow path 130 is blocked from flowing into the inlet 110 or the outlet 120 by the first blocking wall 150 and the second blocking wall 160. can

The catalyst 200 is filled in the passage 130 of the electrode body 100 . The catalyst 200 may be formed of a plurality of particle structures. The catalyst 200 may be formed of a reduction catalyst or an oxidation catalyst known in the art.

Referring to FIG. 3, the inlet 110 and the outlet 120 of the electrode body 100 are respectively connected to the first surface 101 of the electrode body 100, for example, from the upper surface to the first surface 101. It consists of a hole structure through to the facing second surface 102, for example, the lower surface.

The passage 130 is provided on the first surface 101 of the electrode body 100 and connects the inlet 110 and the outlet 120 .

The sealing groove 140 is formed outside the inlet 110 and the outlet 120 and is provided on the first surface 101 of the electrode body 100 .

The first blocking wall 150 is provided on the lower surface of the flow path 130 at the boundary between the inlet 110 and the flow path 130, and the second blocking wall 160 is provided on the outlet 120. ) and the lower surface of the flow path 130 at the interface between the flow path 130. The upper ends of the first blocking wall 150 and the second blocking wall 160 may have the same height as the height of the first surface 101 of the electrode body 100 . Referring to the drawing drawn out by the arrow in FIG. 3, each of the first blocking wall 150 and the second blocking wall 160 is provided with a plurality of holes H, through the plurality of holes H. Liquid or gaseous reactants can move easily.

The catalyst 200 is filled in the flow path 130 . The diameter of the catalyst 200 is larger than the diameter of the plurality of holes H provided in each of the first blocking wall 150 and the second blocking wall 160, so that the catalyst 200 is formed through the hole ( H) will not be able to move through. Therefore, the catalyst 200 is trapped in the flow path 130 without flowing into the inlet 110 and the outlet 120 by the first blocking wall 150 and the second blocking wall 160 .

When the catalyst-electrode structure according to an embodiment of the present invention constitutes the reduction electrode 10 of FIG. 1 described above, carbon dioxide is supplied through the inlet 110, and the supplied carbon dioxide is the first blocking wall ( After passing through the hole H of 150), it moves through the passage 130 and reacts while contacting the catalyst 200 to produce synthesis gas, and the produced synthesis gas passes through the second barrier wall 160 After passing through the hole H of, it is discharged through the outlet 120.

In addition, when the catalyst-electrode structure according to an embodiment of the present invention constitutes the anode 20 of FIG. 1 described above, an aqueous electrolyte solution including water is supplied through the inlet 110, and the supplied water is After passing through the hole H of the first barrier wall 150, it moves through the passage 130 and reacts while contacting the catalyst 200 to produce oxygen gas. 2 After passing through the hole (H) of the blocking wall (160), it is discharged through the outlet (120).

Referring to FIG. 4 , the passage 130 and the sealing groove 140 have a groove structure provided on the first surface 101 of the electrode body 100 . In this case, the depth H1 of the passage 130 may be formed deeper than the depth H2 of the sealing groove 140 . Accordingly, a sufficient amount of the catalyst 200 can be filled in the passage 130, so that the contact area between the reducing material or the oxidizing material and the catalyst 200 can be increased.

The catalyst 200 may fill the entire inside of the passage 130 . Therefore, the catalyst 200 can contact both the bottom surface and the side surface of the flow path 130, and thus, the reducing material or oxidizing material moving along the flow path 130 has a contact area with the catalyst 200. can increase An upper end of the catalyst 200 may be formed at the same height as the first surface 101 of the electrode body 100 .

5 is a cross-sectional view showing a coupling structure of a reduction electrode, an oxidation electrode, and a separator according to an embodiment of the present invention.

As can be seen from FIG. 5, the reduction electrode 10 and the oxidation electrode 20 are composed of the catalyst-electrode structure according to FIGS. 2 to 4 described above.

At this time, the catalyst 200 of the catalyst-electrode structure constituting the reduction electrode 10 faces the catalyst 200 of the catalyst-electrode structure constituting the oxidation electrode 20 . In addition, the sealing groove 140 of the catalyst-electrode structure constituting the reduction electrode 10 overlaps and faces the sealing groove 140 of the catalyst-electrode structure constituting the oxidation electrode 20 .

A separator 30 and a sealing member 300 are formed between the reduction electrode 10 and the oxidation electrode 20 .

The separation membrane 30 is provided to contact the catalyst 200 of the reduction electrode 10 and the catalyst 200 of the oxidation electrode 20 . In addition, the separator 30 is in contact with the first and second blocking walls 150 and 160 of the reduction electrode 10 and the first and second blocking walls 150 and 160 of the oxidation electrode 20 . It is available.

In addition, the separation membrane 30 overlaps the inlet 110 and the outlet 120 of the catalyst-electrode structure constituting the reduction electrode 10 and the inlet of the catalyst-electrode structure constituting the oxidation electrode 20. It also overlaps with (110) and outlet (120). In addition, the separator 30 is also connected to the first surface 101 of the catalyst-electrode structure constituting the reduction electrode 10 and the first surface 101 of the catalyst-electrode structure constituting the oxidation electrode 20. It can be extended to touch. In addition, both ends of the separation membrane 30 may be in contact with the sealing member 300 .

The sealing member 300 is inserted into the sealing groove 140 of the catalyst-electrode structure constituting the reduction electrode 10 and the sealing groove 140 of the catalyst-electrode structure constituting the oxidation electrode 20. .

6 is a plan view of a catalyst-electrode structure according to another embodiment of the present invention. The catalyst-electrode structure according to FIG. 6 is the same as the catalyst-electrode structure according to FIG. 2 except that the structure of the flow path 130 is changed. Therefore, the same reference numerals are assigned to the same components, and only different configurations will be described below.

In the case of FIG. 2 , the flow path 130 has a curved straight structure between the inlet 110 and the outlet 120 . In contrast, in the case of FIG. 6 , the passage 130 has a mesh structure between the inlet 110 and the outlet 120 . Compared to the case of FIG. 2, in the case of FIG. 6, the length of the passage 130 may be extended, and accordingly, the catalyst 200 in which the reducing material or oxidizing material flowing through the passage 130 is filled in the passage 130 ), the reaction efficiency can be improved by increasing the contact time.

The flow path 130 according to the present invention is not necessarily limited to the structure of FIG. 2 or 6, and may include various structures capable of connecting the inlet 110 and the outlet 120. For example, the passage 130 may include various curved passages connecting the inlet 110 and the outlet 120 .

7 is a schematic diagram of an electrochemical reactor according to another embodiment of the present invention.

As can be seen in FIG. 7, the electrochemical reaction device according to another embodiment of the present invention includes a reduction electrode 10, an oxidation electrode 20, a separator 30, a reducing material input/output unit 40, an oxide input/output unit ( 50), a reducing material circulation unit 60, and an oxidizing material circulation unit 70.

At least one of the reduction electrode 10 and the oxidation electrode 20 may be formed of the catalyst-electrode structure according to the above-described embodiment.

At this time, the reduction electrode 10 is provided so that carbon dioxide is reduced to produce carbon monoxide and hydrogen. To this end, the cathode 10 may include a silver catalyst, particularly a silver nano-catalyst, but is not necessarily limited thereto.

An aqueous amine solution in which carbon dioxide is captured may be introduced into the reduction electrode 10 .

The amines include tertiary amines, preferably tertiary amines without OH groups. The tertiary amine without an OH group may include triethylamine (TEA).

The triethylamine (TEA) may be represented by R ₃ N (where R is CH ₂ CH ₃ ) as shown in Formula 1 below.

Formula 1

As such, according to one embodiment of the present invention, carbon dioxide can be introduced into the cathode 10 in a state of being captured in an amine solution, and the carbon dioxide capture reaction using the amine aqueous solution is shown in Scheme 1 below.

Scheme 1

CO ₂ + R ₃ N + H ₂ O → R ₃ NH ⁺ +HCO ₃ ^-

Accordingly, carbon dioxide is included in the aqueous amine solution in the form of ions such as HCO ₃ ^- , and the aqueous amine solution including HCO ₃ ^- may be introduced into the cathode 10 .

The reducing material input/output unit 40 connects the reducing material circulation unit 60 and the reduction electrode 10, and includes an inlet 41 and an outlet 42.

Through the inlet 41, the amine aqueous solution in which the carbon dioxide stored in the reducing material circulation unit 60 is captured enters the reduction electrode 10, and the carbon dioxide is reduced from the outlet 42. The aqueous amine solution in which gas and unreacted carbon dioxide are collected comes out of the reduction electrode 10 . The synthetic gas coming out of the outlet 42 and the amine aqueous solution in which unreacted carbon dioxide is collected are supplied to the reducing material circulation unit 60 again. At this time, the synthesis gas containing carbon monoxide and hydrogen is separated in the reducing material circulation unit 60, and the aqueous amine solution in which the unreacted carbon dioxide is collected is introduced into the reduction electrode 10 through the inlet 41. move

In the reduction electrode 10 as described above, carbon monoxide is generated while continuous reactions of Reaction Formula 2 and Reaction Formula 3 below occur.

Scheme 2

HCO ₃ ^- + H ⁺ → CO ₂ + H ₂ O

Scheme 3

_CO2 + H ₂ O + 2e ^- → CO + 2OH ^-

The oxide material input/output part 50 includes an inlet 51 and an outlet 52 while connecting the oxide material circulation part 70 and the oxidation electrode 20 .

Through the inlet 51, the aqueous electrolyte solution stored in the oxidant circulation unit 70 enters the inside of the oxidation electrode 20, and oxygen and The aqueous electrolyte solution comes out of the oxidation electrode 20 . The aqueous electrolyte solution coming out of the outlet 52 is supplied to the oxide circulation unit 70 again. At this time, oxygen may be separated from the oxidant circulation unit 70 .

In the oxidation electrode 10 as described above, oxygen is generated while the reaction of Reaction Formula 4 below occurs.

Scheme 4

2OH ^- → 2e ^- + 1/2 O ₂ + H ₂ O

The separator 30 is provided between the reduction electrode 10 and the oxidation electrode 20 . The separation membrane 30 is preferably made of a bipolar membrane.

When the separation membrane 30 is made of an anion exchange membrane, bicarbonate ions (HCO3-) contained in the tertiary amine aqueous solution can move toward the oxidation electrode 20, and as a result, the carbon dioxide present on the reduction electrode 10 As the amount of is reduced, the efficiency of the synthesis gas generation reaction performed in the cathode 10 may be reduced.

In addition, when the separation membrane 30 is formed of a cation exchange membrane, hydrogenated amines included in the tertiary amine aqueous solution, for example (CH ₂ CH ₃ ) ₃ NH ⁺ ions, can move toward the oxidation electrode 20, and the Electrolyte cations in the aqueous solution on the anode 20 side, for example, potassium ions (K ⁺ ) derived from potassium hydroxide can move to the cathode 10 side, and as a result, synthesis gas formed on the cathode 10 side. The efficiency of the production reaction may be reduced

In contrast, when the separation membrane 30 is made of a bipolar membrane, the separation membrane 30 allows OH ^- to move to the oxidation electrode 20 and H ⁺ to move to the reduction electrode 10, and also , HCO ₃ ^- is prevented from moving to the oxidation electrode 20, so that the hydrogen generation efficiency in the reduction electrode 10 and the oxygen generation efficiency in the oxidation electrode 20 can be improved.

The reducing material circulation unit 60 supplies the aqueous amine solution in which carbon dioxide is captured to the reduction electrode 10 and receives the synthetic gas generated at the reduction electrode 10 and the aqueous amine solution in which unreacted carbon dioxide is captured. play a role

A pump is provided between the reducing material circulating unit 60 and the reduction electrode 10 to reduce the amine aqueous solution in which carbon dioxide is captured under a high pressure of 5 bar or more, preferably 20 bar or more. It can be supplied to the electrode (10).

The synthesis gas may be separated in the reducing material circulation unit 60 and supplied to a hydrogen carrier manufacturing device described later, and the aqueous amine solution in which the unreacted carbon dioxide is collected is circulated while moving into the reduction electrode 10 do.

The oxide circulation unit 70 serves to supply an aqueous electrolyte solution such as KOH to the anode 20 and to receive oxygen and an aqueous electrolyte solution generated in the anode 20 . A pump may also be provided between the oxide circulation unit 70 and the oxidation electrode 20 .

The oxygen is separated in the oxide circulation unit 70, and the aqueous electrolyte solution is circulated while moving into the oxidation electrode 20.

8 is a schematic diagram of a carbon dioxide utilization system according to an embodiment of the present invention.

As can be seen in FIG. 8, the carbon dioxide utilization system according to an embodiment of the present invention includes a carbon dioxide capture device 1, an electrochemical reaction device 2, a hydrogen carrier manufacturing device 3, a dehydrogenation device 4, and hydrogen utilization. It consists of a device (5).

The carbon dioxide collecting device 1 is a device for capturing carbon dioxide generated in various fields, for example, carbon dioxide contained in the atmosphere by factories, power plants, or automobiles, etc., and includes an aqueous amine solution. Specifically, the carbon dioxide capture device 1 includes amine and water, and the amine includes tertiary amine, preferably tertiary amine without an OH group. The tertiary amine without an OH group may include triethylamine (TEA).

The electrochemical reaction device 2 generates synthesis gas using the carbon dioxide collected in the carbon dioxide capture device 1. The electrochemical reactor 2 may have a structure according to FIG. 7 described above.

In the conventional case, as an example, after capturing carbon dioxide from exhaust gas, the captured carbon dioxide is separated again and introduced into the electrochemical reaction device 2, but according to an embodiment of the present invention, the carbon dioxide captured in the carbon dioxide capture device 1 A state in which carbon dioxide is captured in the aqueous amine solution, more specifically, an aqueous amine solution including HCO ₃ ⁻ is introduced into the electrochemical reactor 2 without going through a separation process for separating carbon dioxide from the aqueous amine solution.

Therefore, the present invention has the advantage of saving the cost of the carbon dioxide separation process compared to the conventional case. In addition, in the case of the prior art, despite the separation of high-purity carbon dioxide through a separation process, the production rate of synthesis gas generated in the electrochemical reaction device 2 is low, resulting in low carbon dioxide conversion efficiency, but in the case of the present invention, the separation process There is an advantage in that the carbon dioxide conversion efficiency is improved compared to the prior art by using relatively low-purity carbon dioxide that has not been passed through. In addition, in the conventional case, the system is unstable due to the crossover of the separated carbon dioxide to the counter electrode, but in the case of the present invention, carbon dioxide is collected in the amine aqueous solution and introduced into the electrochemical reaction device Therefore, crossover in which carbon dioxide passes to the counter electrode does not occur. In addition, in the conventional case, an additional process of separating the syngas generated in the electrochemical reaction device 2 from carbon dioxide is required, but in the case of the present invention, since carbon dioxide is circulated in a state captured in an amine aqueous solution, No additional separation process is required.

The electrochemical reaction device 2 includes the aforementioned reduction electrode 10, the oxidation electrode 20, and the separator 30 provided between the reduction electrode 10 and the oxidation electrode 20. In addition, carbon dioxide is reduced in the reduction electrode 10 to produce synthesis gas of carbon monoxide (CO) and hydrogen (H ₂ ). In this case, generating the carbon monoxide (CO) and hydrogen (H ₂ ) at a molar ratio of 1:2 may facilitate the hydrogen carrier manufacturing process in the hydrogen carrier manufacturing apparatus 3 .

Since the hydrogen (H ₂ ) generated in the electrochemical reaction device 2 is not easily transported in a gaseous state, the hydrogen carrier manufacturing device 3 is prepared as a hydrogen carrier in a liquid state that is easy to transport.

The hydrogen carrier manufacturing apparatus 3 may generate methanol as a hydrogen carrier using synthesis gas of carbon monoxide (CO) and hydrogen (H ₂ ) generated in the electrochemical reaction apparatus 2 .

The hydrogen carrier manufacturing apparatus 3 may generate 1 mole of methanol (CH ₃ OH) by reacting 1 mole of carbon monoxide (CO) with 2 moles of hydrogen (H ₂ ) using a thermochemical reactor. Such a reaction may be performed as an exothermic reaction, and the methanol production rate may be improved by using a multi-stage reactor.

According to an embodiment of the present invention, carbon monoxide and hydrogen generated in the above-described electrochemical reactor 2 are supplied to the reactor of the hydrogen carrier manufacturing apparatus 3, and carbon dioxide is supplied to the reactor of the hydrogen carrier manufacturing apparatus 3 not supplied with Therefore, methanol is produced in the reactor of the hydrogen carrier manufacturing apparatus 3, and water is not produced as a by-product. There is no need to install a separate separator such as a still for separating by-product water at the downstream.

When carbon dioxide in addition to carbon monoxide and hydrogen is supplied into the reactor of the hydrogen carrier manufacturing apparatus 3, water as well as methanol may be produced as a product. A separate separator, such as a still, must be installed.

However, according to one embodiment of the present invention, carbon monoxide and hydrogen generated in the electrochemical reactor 2 are supplied to the reactor of the hydrogen carrier manufacturing apparatus 3, and carbon dioxide is supplied to the hydrogen carrier manufacturing apparatus 3 Since it is not supplied to the reactor, there is no need to install a separate separator at the rear of the methanol recovery unit. Therefore, the methanol recovery unit of the hydrogen carrier manufacturing apparatus 3 can be connected to the dehydrogenation unit 4 without having a separate separator at the rear thereof.

The dehydrogenation device 4 may generate hydrogen (H ₂ ) by reforming the methanol produced in the hydrogen carrier manufacturing device 3. Specifically, the dehydrogenation device 4 may generate carbon dioxide and hydrogen by reacting methanol with water. Such a dehydrogenation device 4 may include an electrochemical reactor including an oxidation electrode, a reduction electrode, and a separator provided between the oxidation electrode and the reduction electrode. Carbon dioxide may be generated at an anode of the electrochemical reactor, and hydrogen may be generated at a cathode of the electrochemical reactor.

The carbon dioxide generated in the dehydrogenation device 4 is put into the carbon dioxide capture device 1 and circulated, and the hydrogen generated in the dehydrogenation device 4 is supplied to the hydrogen utilization device 5. Therefore, the system according to an embodiment of the present invention can obtain hydrogen, which is a useful material that can be used for various purposes, while carbon dioxide is circulated.

The hydrogen utilization device 5 may be various devices known in the art capable of utilizing hydrogen. For example, the hydrogen utilization device 5 may include a hydrogen fuel cell using hydrogen as a fuel.

Although the embodiments of the present invention have been described in more detail with reference to the accompanying drawings, the present invention is not necessarily limited to these embodiments, and may be variously modified and implemented without departing from the technical spirit of the present invention. . Therefore, the embodiments disclosed in the present invention are not intended to limit the technical idea of the present invention, but to explain, and the scope of the technical idea of the present invention is not limited by these embodiments. Therefore, it should be understood that the embodiments described above are illustrative in all respects and not restrictive. The protection scope of the present invention should be construed according to the scope of the claims, and all technical ideas within the scope equivalent thereto should be construed as being included in the scope of the present invention.

10: reduction electrode 20: oxidation electrode
30: separation membrane 40: reducing material input and output unit
50: oxide input/output unit 41, 51, 110: entrance
42, 52, 120: outlet 60: reducing material circulation unit
70: oxidative circulation unit 100: body
101: first side 102: second side
130: Euro 140: sealing groove
150: first blocking wall 160: second blocking wall
200: catalyst 300: sealing member

Claims (13)

An electrode body made of a conductive material;
an inlet made of a hole penetrating the electrode body at one side of the electrode body;
an outlet formed of a hole penetrating the electrode body on the other side of the electrode body;
a passage made of a groove provided on one surface of the electrode body and connecting between the inlet and the outlet; and
A catalyst-electrode structure comprising a catalyst filled in the passage. According to claim 1,
The catalyst-electrode structure is filled in the entire inside of the passage and contacts both the lower surface and the side surface of the passage. According to claim 2,
A height of the top of the catalyst is the same as a height of one side of the electrode body. Catalyst-electrode structure. According to claim 1,
A catalyst-electrode structure further comprising a blocking wall for preventing the catalyst from flowing into the inlet or the outlet. According to claim 1,
The catalyst-electrode structure according to claim 1 , wherein the blocking wall includes a first blocking wall provided at an interface between the inlet and the flow path and a second blocking wall provided at an interface between the outlet and the flow path. According to claim 1,
The catalyst-electrode structure of claim 1 , wherein each of the first blocking wall and the second blocking wall includes a plurality of holes, and a diameter of the plurality of holes is smaller than a diameter of the catalyst. According to claim 1,
The catalyst-electrode structure of claim 1, wherein the flow path includes at least one of a curved straight structure, a curved curved structure, and a mesh structure. According to claim 1,
It is made of a groove provided on one surface of the electrode body and further includes a sealing groove provided on the outside of the inlet, the outlet, and the flow path,
The catalyst-electrode structure of claim 1 , wherein the depth of the groove of the passage is greater than that of the groove of the sealing groove. a reduction electrode and an oxidation electrode facing each other;
a separation membrane provided between the reduction electrode and the oxidation electrode;
a reducing material input/output unit connected to the reduction electrode; and
It includes an oxide input/output unit connected to the oxidation electrode,
At least one of the reduction electrode and the oxidation electrode is an electrochemical reaction device composed of the catalyst-electrode structure according to any one of claims 1 to 8. According to claim 9,
The separator is an electrochemical reaction device in contact with one surface of the catalyst and the electrode body while overlapping the inlet, outlet, and flow path provided in the electrode body. According to claim 9,
An electrochemical reaction device in which a tertiary amine aqueous solution containing HCO ₃ ^- is introduced into the reduction electrode to generate carbon monoxide and hydrogen. According to claim 9,
The separator is made of a bipolar membrane, and the bipolar membrane is provided so that OH ⁻ moves to the anode, H ⁺ moves to the reduction electrode, and HCO ₃ ⁻ does not move to the anode for an electrochemical reaction. Device. a carbon dioxide capture device for capturing carbon dioxide;
an electrochemical reaction device for producing synthesis gas by reducing the carbon dioxide collected by the carbon dioxide collecting device;
a hydrogen carrier manufacturing device for manufacturing a hydrogen carrier material using the syngas produced in the electrochemical reactor;
a dehydrogenation device for producing hydrogen from the hydrogen carrier material produced in the hydrogen transport production device; and
Including a hydrogen utilization device that utilizes the hydrogen produced by the dehydrogenation device,
The electrochemical reactor is a carbon dioxide utilization system consisting of the electrochemical reactor according to claim 9.

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