Method and device for electrochemically trapping carbon dioxide

Abstract

The invention provides a method and a device for electrochemical carbon dioxide desorption and absorbent regeneration, and a carbon dioxide trapping method and a carbon dioxide trapping system for hydrogen production by coupling electrolysis of water. An apparatus for electrochemical carbon dioxide desorption and absorbent regeneration comprises an electrolytic cell comprising at least one electrolysis cell arranged in a stack, each electrolysis cell comprising an anode chamber, a cathode chamber and an intermediate chamber located between the anode chamber and the cathode chamber, the anode chamber and the middle chamber are separated by a cation exchange membrane, the middle chamber and the cathode chamber are separated by a gas isolation membrane, and the gas isolation membrane is configured to isolate gas but allow positive ions and water to pass through. Electrochemical carbon dioxide pregnant solution desorption and absorbent regeneration with high desorption rate and low desorption energy consumption are realized, and industrial application of high-concentration organic amine in carbon dioxide absorption, electrochemical desorption and regeneration processes becomes possible.

Description

Technical Field

[0001] This invention relates to the field of carbon dioxide capture, utilization and storage technology, specifically to a method and apparatus for electrochemical carbon dioxide desorption and absorbent regeneration, and a carbon dioxide capture method and system coupled with water electrolysis to produce hydrogen. Background Technology

[0002] Carbon dioxide capture is a crucial technology for deep emission reduction in fossil fuel industries such as thermal power, steel, cement, and chemicals. In carbon dioxide capture, the desorption rate and desorption energy consumption are key factors to consider. Therefore, technologies utilizing electrolysis for electrochemical desorption of carbon dioxide-rich solutions and regeneration of absorbents have been developed.

[0003] However, existing electrochemical carbon dioxide rich solution desorption and absorbent regeneration technologies have low desorption rates and high desorption energy consumption. In particular, for organic amine absorbents, they are only suitable for systems with low concentrations of organic amine absorbents, and their industrial application value is not high. Summary of the Invention

[0004] In view of the above problems, the present invention proposes a method and apparatus for electrochemical carbon dioxide desorption and absorbent regeneration, and a carbon dioxide capture method and system coupled with water electrolysis for hydrogen production, to overcome or at least partially solve the above problems.

[0005] One object of the present invention is to achieve electrochemical carbon dioxide-rich liquid desorption and absorbent regeneration with high desorption rate and low desorption energy consumption.

[0006] A further objective of this invention is to promote the full progress of the acid desorption of carbon dioxide and stabilize the voltage, thereby further improving the desorption rate and reducing the desorption energy consumption.

[0007] In particular, according to one aspect of the present invention, an apparatus for electrochemical carbon dioxide desorption and absorbent regeneration is provided, comprising an electrolytic cell, the electrolytic cell comprising at least one stacked electrolytic chamber, each electrolytic chamber comprising:

[0008] The anode chamber, located in the anode region, is configured to undergo an anodic oxidation reaction to generate hydrogen ions; and

[0009] The cathode chamber and intermediate chamber are located in the cathode region. The intermediate chamber is located between the anode chamber and the cathode chamber. The intermediate chamber is configured to allow the input carbon dioxide-rich solution to react with hydrogen ions from the anode chamber to electrochemically desorb carbon dioxide and produce carbon dioxide and carbon dioxide-poor solution. The cathode chamber is configured to receive the carbon dioxide-poor solution from the intermediate chamber and cause the carbon dioxide-poor solution to undergo electrochemical hydrogen evolution to produce hydrogen gas and regenerated absorbent.

[0010] The anode chamber is separated from the intermediate chamber by a cation exchange membrane, and the intermediate chamber is separated from the cathode chamber by a gas-barrier membrane. The gas-barrier membrane is configured to isolate gases but allow cations and water to pass through it.

[0011] Optionally, the air-barrier membrane is an asbestos membrane, a polyphenylene sulfide-based composite membrane, or a polymer porous membrane;

[0012] The cation exchange membrane is a proton exchange membrane.

[0013] Optionally, the asbestos membrane is a polytetrafluoroethylene resin modified asbestos membrane;

[0014] The polymer porous membrane is a polyether ether ketone porous membrane or a polysulfone porous membrane.

[0015] Optionally, the thickness of the intermediate chamber is in the range of 0.1 mm to 5.0 mm;

[0016] The intermediate chamber is filled with a solid filling medium with a porosity of 10%-90%.

[0017] Optionally, the solid filling medium is one or more of the following: metal mesh, foamed metal, foamed ceramic, plastic mesh, porous plastic, ceramic microspheres, glass microspheres, polymer microspheres, cation exchange resin, and anion exchange resin.

[0018] Optionally, the electrolytic cell is provided with a cathode end plate and an anode end plate at both ends, and two adjacent electrolytic cells inside the electrolytic cell are separated by bipolar plates. An anode electrode and a cathode electrode are closely distributed on both sides of each bipolar plate.

[0019] Optionally, the apparatus for electrochemical carbon dioxide desorption and absorbent regeneration also includes:

[0020] The rich liquid input element is connected to the liquid inlet of the intermediate chamber and is used to deliver carbon dioxide rich liquid into the intermediate chamber through the liquid inlet of the intermediate chamber.

[0021] A first gas-liquid separator, whose inlet and outlet are respectively connected to the outlet of the intermediate chamber and the inlet of the cathode chamber, is used to separate the gas and liquid of the mixture of carbon dioxide and carbon dioxide-lean solution from the intermediate chamber, and to transport the separated carbon dioxide-lean solution into the cathode chamber; and

[0022] The second gas-liquid separator has its inlet connected to the outlet of the cathode chamber. It is used to separate the mixed fluid of hydrogen and regenerated absorbent from the cathode chamber. The outlet of the second gas-liquid separator is configured to be connected to an external carbon dioxide absorption device so that the separated regenerated absorbent can be output to the carbon dioxide absorption device through the outlet of the second gas-liquid separator.

[0023] Optionally, the apparatus for electrochemical carbon dioxide desorption and absorbent regeneration also includes:

[0024] The carbon dioxide loading test element is connected to the outlet of the second gas-liquid separator and is used to detect the carbon dioxide loading in the regenerated absorbent output from the outlet of the second gas-liquid separator.

[0025] A gas detection element is connected to the outlet of the first gas-liquid separator and the second gas-liquid separator, respectively, to detect the amount of hydrogen and carbon dioxide produced; and

[0026] The control element is communicatively connected to the carbon dioxide load testing element and the gas detection element, respectively. It is configured to determine the ratio of carbon dioxide to hydrogen produced based on the detected amounts of hydrogen and carbon dioxide, and to control the operating parameters of the electrolyzer based on the determined ratio of carbon dioxide to hydrogen and the carbon dioxide load in the regenerated absorbent.

[0027] Optionally, the anodic oxidation reaction is an electrochemical oxygen evolution reaction, and the anode chamber is configured to perform an electrochemical oxygen evolution reaction on water to produce hydrogen ions and oxygen.

[0028] The catalyst for the anode electrode is iridium dioxide supported on a gas diffusion electrode, and the catalyst for the cathode electrode is a platinum / carbon catalyst supported on a gas diffusion electrode.

[0029] The electrochemical carbon dioxide desorption and absorbent regeneration device also includes:

[0030] The third gas-liquid separator has its inlet and outlet connected to the outlet and inlet of the anode chamber, respectively. It is used to separate the mixed fluid of oxygen and water from the anode chamber and to recycle the separated water back into the anode chamber.

[0031] Optionally, the anodic oxidation reaction is an electrochemical hydrogen oxidation reaction, the inlet of the anode chamber is connected to the outlet of the second gas-liquid separator, and the anode chamber is configured to perform an electrochemical oxidation reaction on the hydrogen separated from the second gas-liquid separator to generate hydrogen ions;

[0032] The catalyst for the anode electrode is a platinum / carbon catalyst supported on a gas diffusion electrode, and the catalyst for the cathode electrode is a platinum / carbon catalyst supported on a gas diffusion electrode.

[0033] According to another aspect of the present invention, a carbon dioxide capture system coupled with water electrolysis for hydrogen production is also provided, comprising:

[0034] A carbon dioxide absorption device is configured to absorb carbon dioxide from a gas to be treated using an absorbent, thereby obtaining a carbon dioxide-rich liquid and purified gas.

[0035] The carbon dioxide capture system coupled with water electrolysis to produce hydrogen also includes any of the aforementioned devices for electrochemical carbon dioxide desorption and absorbent regeneration.

[0036] The rich liquid outlet and the lean liquid inlet of the carbon dioxide absorption device are respectively connected to the electrochemical carbon dioxide desorption and absorbent regeneration device. The carbon dioxide absorption device is configured to input the rich carbon dioxide solution into the electrochemical carbon dioxide desorption and absorbent regeneration device through the rich liquid outlet, and receive the regenerated absorbent from the electrochemical carbon dioxide desorption and absorbent regeneration device through the lean liquid inlet. The absorbent is an organic amine absorbent.

[0037] According to another aspect of the present invention, a method for electrochemical carbon dioxide desorption and absorbent regeneration is also provided, performed using any of the aforementioned apparatus for electrochemical carbon dioxide desorption and absorbent regeneration, the method comprising:

[0038] The input carbon dioxide-rich solution is electrolyzed in an electrolyzer to obtain carbon dioxide, hydrogen, and regenerated absorbent in the cathode region of the electrolyzer. During the electrolysis process, the ratio of carbon dioxide and hydrogen obtained and the carbon dioxide loading of the regenerated absorbent are adjusted by controlling the operating parameters of the electrolyzer. The operating parameters of the electrolyzer include at least one of the following: the voltage of the electrolyzer, the current density of the electrolyzer, the operating temperature of the electrolyzer, and the cathode pressure of the electrolyzer.

[0039] Optionally, the ratio of carbon dioxide to hydrogen is 1:1 to 1:10, and the carbon dioxide loading of the regenerated absorbent is 0 to 45% of the carbon dioxide loading of the carbon dioxide-rich solution.

[0040] The voltage of the electrolytic cell is 0-8V, and the current density of the electrolytic cell is 100-20000A / m³. 2 The operating temperature of the electrolytic cell is 20-100℃, and the cathode pressure of the electrolytic cell is between atmospheric pressure and 50 bar.

[0041] According to another aspect of the present invention, a carbon dioxide capture method coupled with water electrolysis for hydrogen production is also provided, comprising:

[0042] Carbon dioxide is absorbed from the gas to be treated using an absorbent in a carbon dioxide absorption device to obtain a carbon dioxide-rich liquid and purified gas.

[0043] The aforementioned electrochemical carbon dioxide desorption and absorbent regeneration method is used to electrolyze carbon dioxide-rich liquid to desorb carbon dioxide and regenerate the absorbent, thereby obtaining carbon dioxide, hydrogen, and the regenerated absorbent.

[0044] At least a portion of the regenerated absorbent is recycled back into the carbon dioxide absorption unit to absorb carbon dioxide.

[0045] Optionally, the absorbent is an organic amine absorbent, comprising: 20-30 wt.% of a main solvent, 4-8 wt.% of a first auxiliary additive, 4-8 wt.% of a second auxiliary additive, and the balance being water;

[0046] The main solvent is an organic amine compound, the first auxiliary additive is an amino acid, and the second auxiliary additive is a hydroxide.

[0047] Optionally, the organic amine compound is one or more selected from ethanolamine, N-methyldiethanolamine, isopropanolamine, piperazine, and hydroxyethylpiperazine;

[0048] The amino acid is one or more of glycine, proline, D-alanine, 2-aminoisobutyric acid, sarcosine, D-2-aminobutyric acid, and taurine.

[0049] The hydroxide is potassium hydroxide and / or sodium hydroxide.

[0050] In the electrochemical carbon dioxide desorption and absorbent regeneration method and apparatus provided by this invention, the electrolytic cell adopts a three-chamber structure, namely, each electrolytic chamber includes an anode chamber, a cathode chamber, and an intermediate chamber located between the two. In the anode chamber, an anodic oxidation reaction occurs to generate hydrogen ions; in the intermediate chamber, acid desorption of carbon dioxide occurs to release carbon dioxide; and in the cathode chamber, electrochemical hydrogen evolution occurs to generate hydrogen gas. Specifically, the intermediate chamber and the cathode chamber are separated by a gas-barrier membrane. Because this gas-barrier membrane has the property of isolating gases but allowing cations and water to pass through it, it can prevent carbon dioxide generated in the intermediate chamber from entering the cathode chamber and recombining with the regenerated absorbent without affecting the mass transfer of ions and water, thereby achieving a high desorption rate and low desorption energy consumption.

[0051] Furthermore, for capture systems using organic amine absorbents, replacing the cation exchange membrane with a gas-barrier membrane to separate the intermediate and cathode chambers enables the regeneration of high-concentration organic amines without the need for a supporting electrolyte. Taking monoethanolamine (MEA) as an example, the commonly used industrial MEA concentration is 5M. When using a cation exchange membrane, protonated organic amines have difficulty passing through the membrane, thus requiring the addition of at least a 5M supporting electrolyte for conductivity. However, due to solubility limitations, a 5M or 10M supporting electrolyte is practically impossible to find. This makes the existing method of separating the intermediate and cathode chambers with a cation exchange membrane unsuitable for the regeneration of high-concentration organic amines. The present invention creatively replaces the cation exchange membrane with a gas-barrier membrane, avoiding the use of a supporting electrolyte. This makes the industrial application of high-concentration organic amines in carbon dioxide absorption, electrochemical desorption, and regeneration processes possible, thus possessing greater industrial application value.

[0052] Furthermore, the intermediate chamber is filled with a solid filling medium (especially a solid electrolyte, such as a cation exchange resin or anion exchange resin), which acts as a buffer for the acid desorption of carbon dioxide, promoting the full progress of the acid desorption of carbon dioxide. At the same time, it can refine the carbon dioxide bubbles and prevent the generated large bubbles from causing drastic voltage fluctuations (such as a sudden voltage rise), that is, it plays a role in stabilizing the voltage, thereby further improving the desorption rate and reducing the desorption energy consumption.

[0053] The above description is merely an overview of the technical solution of the present invention. In order to better understand the technical means of the present invention and to implement it in accordance with the contents of the specification, and in order to make the above and other objects, features and advantages of the present invention more apparent and understandable, specific embodiments of the present invention are described below.

[0054] The above and other objects, advantages and features of the present invention will become more apparent to those skilled in the art from the following detailed description of specific embodiments of the invention in conjunction with the accompanying drawings. Attached Figure Description

[0055] To more clearly illustrate the technical solution of the present invention, some embodiments of the present invention will be described below with reference to the accompanying drawings. Those skilled in the art should understand that the same reference numerals may indicate the same or similar parts or components in different drawings; the drawings of the present invention are not necessarily drawn to scale.

[0056] In the attached diagram:

[0057] Figure 1 This is a schematic diagram of a carbon dioxide capture system coupled with water electrolysis for hydrogen production according to an embodiment of the present invention, wherein the carbon dioxide capture system coupled with water electrolysis for hydrogen production includes a device for electrochemical carbon dioxide desorption and absorbent regeneration.

[0058] Figure 2 This is a schematic diagram of a carbon dioxide capture system coupled with water electrolysis for hydrogen production according to another embodiment of the present invention, wherein the carbon dioxide capture system coupled with water electrolysis for hydrogen production includes a device for electrochemical carbon dioxide desorption and absorbent regeneration.

[0059] Figure 3 A schematic diagram illustrating the operating principle of a carbon dioxide capture system coupled with electrolysis of water to produce hydrogen according to an embodiment of the present invention, and the included electrochemical carbon dioxide desorption and absorbent regeneration apparatus.

[0060] Figure 4 This is a schematic flowchart of a carbon dioxide capture method for hydrogen production via coupled water electrolysis according to an embodiment of the present invention.

[0061] Figure 5 This is a schematic diagram of the specific process of a carbon dioxide capture method for hydrogen production by coupled water electrolysis according to an embodiment of the present invention. Detailed Implementation

[0062] Those skilled in the art should understand that the embodiments described below are merely a part of the embodiments of the present invention, and not all of the embodiments of the present invention. These partial embodiments are intended to explain the technical principles of the present invention and are not intended to limit the scope of protection of the present invention. Based on the embodiments provided by the present invention, all other embodiments obtained by those skilled in the art without creative effort should still fall within the scope of protection of the present invention.

[0063] Furthermore, one or more examples of embodiments of the invention are illustrated in the accompanying drawings. Each example is provided by way of explanation and is not intended to limit the invention. In fact, it will be apparent to those skilled in the art that various modifications and variations can be made to the invention without departing from the scope or spirit of the invention. For example, features shown or described as part of one embodiment may be used with another embodiment to produce yet another embodiment.

[0064] It should be noted that in the description of this invention, terms such as "center," "upper," "lower," "top," "bottom," "left," "right," "vertical," "horizontal," "inner," and "outer," which indicate direction or positional relationships, are based on the direction or positional relationships shown in the accompanying drawings. These are used merely for ease of description and do not indicate or imply that the device or element must have a specific orientation, or be constructed and operated in a specific orientation; therefore, they should not be construed as limitations on this invention. Furthermore, terms such as "first," "second," and "third," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0065] Furthermore, it should be noted that, in the description of this invention, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "joining" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a direct connection, an indirect connection through intermediate components, or a connection within two components. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0066] Figure 1 This is a schematic diagram of a carbon dioxide capture system 100 coupled with water electrolysis for hydrogen production according to an embodiment of the present invention. Figure 2 This is a schematic diagram of a carbon dioxide capture system 100 coupled with water electrolysis to produce hydrogen according to another embodiment of the present invention.

[0067] See Figure 1 and Figure 2As shown, the carbon dioxide capture system 100 coupled with water electrolysis to produce hydrogen generally includes a carbon dioxide absorption device 1 and an electrochemical carbon dioxide desorption and absorbent regeneration device 200.

[0068] The carbon dioxide absorption device 1 is configured to absorb carbon dioxide from the gas to be treated using an absorbent, thereby obtaining a carbon dioxide-rich solution and purified gas. The carbon dioxide absorption device 1 (e.g., an absorption tower 1) has a rich solution outlet 105 typically located at its bottom and a lean solution inlet 104 typically located at its top. The rich solution outlet 105 and the lean solution inlet 104 are respectively connected to an electrochemical carbon dioxide desorption and absorbent regeneration device 200. The carbon dioxide absorption device 1 feeds the carbon dioxide-rich solution to the electrochemical carbon dioxide desorption and absorbent regeneration device 200 through the rich solution outlet 105, and receives regenerated absorbent from the electrochemical carbon dioxide desorption and absorbent regeneration device 200 through the lean solution inlet 104, thereby achieving the recycling of the absorbent.

[0069] Furthermore, the carbon dioxide absorption device 1 may also have a gas inlet 101 at its lower part for introducing the gas to be treated into the absorption device 1; an absorbent inlet 103 at its upper part for replenishing the absorption device 1 with fresh absorbent; and a purified gas outlet 102 at its top for discharging the treated purified gas. The gas to be treated may be, for example, air, combustion exhaust gas, etc.

[0070] The carbon dioxide capture system 100 of this invention combines water electrolysis for hydrogen production with carbon dioxide desorption and absorbent regeneration, achieving optimization of energy and cost.

[0071] In some embodiments, the absorbent is an organic amine absorbent. The carbon dioxide capture system 100 of the present invention is particularly suitable for systems using organic amine absorbents.

[0072] In some optional embodiments, the organic amine absorbent comprises: 20-30 wt.% of a main solvent, 4-8 wt.% of a first auxiliary additive, 4-8 wt.% of a second auxiliary additive, and the balance being water, wherein the main solvent is an organic amine compound, the first auxiliary additive is an amino acid, and the second auxiliary additive is a hydroxide.

[0073] The organic amine absorbent is in the form of a homogeneous solution. Preferably, the total concentration of the main solvent, the first auxiliary additive, and the second auxiliary additive in the organic amine absorbent is 30-45 wt.%.

[0074] In some specific embodiments, the organic amine compound may be one or more of ethanolamine, N-methyldiethanolamine, isopropanolamine, piperazine, hydroxyethylpiperazine, etc.

[0075] In some specific embodiments, the amino acid can be one or more of glycine, proline, D-alanine, 2-aminoisobutyric acid, sarcosine, D-2-aminobutyric acid, taurine, etc.

[0076] In some specific embodiments, the hydroxide may be potassium hydroxide and / or sodium hydroxide.

[0077] In this embodiment of the invention, by optimizing the formulation of the organic amine absorbent, better overall performance in terms of capture efficiency, desorption rate, and desorption energy consumption is achieved.

[0078] The following is a detailed description of the apparatus 200 for electrochemical carbon dioxide desorption and absorbent regeneration.

[0079] Reference Figure 1 and Figure 2 As shown, the electrochemical carbon dioxide desorption and absorbent regeneration apparatus 200 includes an electrolytic cell 201. The electrolytic cell 201 includes at least one stacked electrolytic chamber 202. Each electrolytic chamber 202 includes: an anode chamber 15 located in the anode region, configured to undergo an anodic oxidation reaction to generate hydrogen ions; and a cathode chamber 14 and an intermediate chamber 16 located in the cathode region. The intermediate chamber 16 is located between the anode chamber 15 and the cathode chamber 14. The intermediate chamber 16 is configured to allow the input carbon dioxide-rich solution to react with hydrogen ions from the anode chamber 15 to perform electrochemical desorption of carbon dioxide to generate carbon dioxide and a carbon dioxide-poor solution. The cathode chamber 14 is configured to receive the carbon dioxide-poor solution from the intermediate chamber 16 and cause the carbon dioxide-poor solution to undergo electrochemical hydrogen evolution to generate hydrogen gas and regenerated absorbent.

[0080] Specifically, the anode chamber 15 and the intermediate chamber 16 are separated by a cation exchange membrane 17, that is, the cathode region and the anode region of the electrolysis chamber 202 are separated by the cation exchange membrane 17. Preferably, the cation exchange membrane 17 is a proton exchange membrane.

[0081] The intermediate chamber 16 is separated from the cathode chamber 14 by a gas-barrier membrane 18, which is configured to block gases but allow cations and water to pass through it.

[0082] In some preferred embodiments, the air barrier membrane 18 can be an asbestos membrane, a polyphenylene sulfide-based composite membrane, or a polymer porous membrane, etc.

[0083] Specifically, the asbestos membrane can be a polytetrafluoroethylene resin modified asbestos membrane. The polymer porous membrane can be a polyetheretherketone porous membrane or a polysulfone porous membrane, etc.

[0084] In the electrochemical carbon dioxide desorption and absorbent regeneration method and apparatus provided by the present invention, the electrolytic cell 201 employs a three-chamber structure for its electrolysis chambers 202, namely, each electrolysis chamber 202 includes an anode chamber 15, a cathode chamber 14, and an intermediate chamber 16 located between the two. Specifically, the intermediate chamber 16 is separated from the cathode chamber 14 by a gas-barrier membrane 18. Because this gas-barrier membrane 18 has the property of isolating gases but allowing cations and water to pass through it, it can prevent carbon dioxide generated in the intermediate chamber 16 from entering the cathode chamber 14 and recombining with the regenerated absorbent without affecting the mass transfer of ions and water, thereby achieving a high desorption rate and low desorption energy consumption.

[0085] Furthermore, for capture systems using organic amine absorbents, replacing the cation exchange membrane with a gas-barrier membrane 18 to separate the intermediate chamber 16 and the cathode chamber 14 enables the regeneration of high-concentration organic amines without the need for a supporting electrolyte. Taking monoethanolamine (MEA) as an example, the commonly used industrial MEA concentration is 5M. When using a cation exchange membrane, protonated organic amines have difficulty passing through the membrane, thus requiring the addition of at least a 5M supporting electrolyte for conductivity. However, due to solubility limitations, a 5M or 10M supporting electrolyte is practically impossible to find. This makes the existing method of separating the intermediate and cathode chambers with a cation exchange membrane unsuitable for the regeneration of high-concentration organic amines. The present invention creatively replaces the cation exchange membrane with a gas-barrier membrane 18, avoiding the use of a supporting electrolyte and enabling the industrial application of high-concentration organic amines in carbon dioxide absorption, electrochemical desorption, and regeneration processes, thus possessing greater industrial application value.

[0086] In some alternative embodiments, the intermediate chamber 16 is filled with a solid filling medium 161.

[0087] Specifically, the solid filling medium 161 can be one or more of the following: metal mesh, foamed metal, foamed ceramic, plastic mesh, porous plastic, ceramic microspheres, glass microspheres, polymer microspheres, cation exchange resin, and anion exchange resin. Preferably, the solid filling medium 161 in the intermediate chamber 16 is a cation exchange resin, and more preferably, a strong acid type cation exchange resin.

[0088] In this embodiment of the invention, the intermediate chamber 16 is filled with a solid filling medium 161, which acts as a buffer zone for the acid desorption of carbon dioxide, promoting the full progress of the acid desorption of carbon dioxide and refining the carbon dioxide bubbles, preventing large bubbles from causing drastic voltage fluctuations (e.g., voltage spikes). In particular, solid electrolytes, such as cation exchange resins and anion exchange resins, not only refine the bubbles but also transfer electrons. Those skilled in the art will understand that in the case of liquid conductivity, the resistance is very high. In this embodiment of the invention, by filling the intermediate chamber 16 with a solid filling medium 161, the bubble refinement and voltage stabilization functions are achieved, thereby further improving the desorption rate and reducing desorption energy consumption.

[0089] Optionally, the porosity of the solid filling medium 161 is between 10% and 90% to fully utilize its bubble refining effect. Specifically, the porosity of the solid filling medium 161 can be 10%, 20%, 30%, 40%, 50%, 60%, 70%, 80%, or 90%.

[0090] In some embodiments, the thickness of the intermediate chamber 16 is set in the range of 0.1 mm to 5.0 mm, for example, 0.5 mm, 1.0 mm, 1.5 mm, 2.0 mm, 2.5 mm, 3.0 mm, 3.5 mm, 4.0 mm, etc., and the intermediate chamber 16 is filled with solid filling medium 161. In this embodiment, by optimizing the thickness of the intermediate chamber 16 (i.e., the filling thickness of the solid filling medium 161), the optimal performance of the electrochemical carbon dioxide desorption and absorbent regeneration device 200 and the entire capture system is ensured. Too thick or too thin a thickness will impair the performance of the system.

[0091] In some embodiments, a cathode end plate 11 and an anode end plate 12 are respectively provided at both ends of the electrolytic cell 201. Two adjacent electrolytic chambers 202 inside the electrolytic cell 201 are separated by bipolar plates 13. An anode electrode and a cathode electrode are closely distributed on both sides of each bipolar plate 13. Figure 1 and Figure 2 The "+" and "-" symbols on both sides of the bipolar plate 13 are shown.

[0092] In some embodiments, the electrochemical carbon dioxide desorption and absorbent regeneration apparatus 200 may further include a rich liquid input element 2, a first gas-liquid separator 6, and a second gas-liquid separator 5.

[0093] The rich solution input element 2 is connected to the inlet of the intermediate chamber 16, and is used to deliver the carbon dioxide rich solution into the intermediate chamber 16 through the inlet of the intermediate chamber 16. The rich solution input element 2 can also be connected to the rich solution outlet 105 of the carbon dioxide absorption device 1, thereby delivering the carbon dioxide rich solution from the carbon dioxide absorption device 1 to the intermediate chamber 16. Specifically, the rich solution input element 2 can be a first pumping device 2, such as a first transfer pump.

[0094] The inlet and outlet of the first gas-liquid separator 6 are connected to the outlet of the intermediate chamber 16 and the inlet of the cathode chamber 14, respectively, for gas-liquid separation of the mixed fluid of carbon dioxide and carbon dioxide lean liquid from the intermediate chamber 16, and for conveying the separated carbon dioxide lean liquid into the cathode chamber 14.

[0095] The inlet of the second gas-liquid separator 5 is connected to the outlet of the cathode chamber 14, and is used to separate the mixed fluid of hydrogen and regenerated absorbent from the cathode chamber 14. The outlet of the second gas-liquid separator 5 is also configured to be connected to the carbon dioxide absorption device 1, specifically, to the lean liquid inlet 104 of the carbon dioxide absorption device 1, so that the separated regenerated absorbent is output through the outlet of the second gas-liquid separator 5, and then the regenerated absorbent is input into the carbon dioxide absorption device 1 through the lean liquid inlet 104.

[0096] In order to smoothly transport the regenerated absorbent from the electrochemical carbon dioxide desorption and absorbent regeneration device 200 to the carbon dioxide absorption device 1, a second pumping device 3, such as a second transfer pump, can be installed between the regenerated absorbent outlet (specifically the liquid outlet of the second gas-liquid separator 5) of the electrochemical carbon dioxide desorption and absorbent regeneration device 200 and the lean liquid inlet 104 of the carbon dioxide absorption device 1.

[0097] In some embodiments, the electrochemical carbon dioxide desorption and absorbent regeneration apparatus 200 may further include a carbon dioxide loading test element 8, a gas detection element 9, and a control element 10.

[0098] The carbon dioxide loading test element 8 is connected to the outlet of the second gas-liquid separator 5 and is used to detect the carbon dioxide loading in the regenerated absorbent output from the outlet of the second gas-liquid separator 5. Specifically, the carbon dioxide loading test element 8 can be installed between the outlet of the second gas-liquid separator 5 and the lean liquid inlet 104 of the carbon dioxide absorption device 1.

[0099] Gas detection element 9 is connected to the outlet of the first gas-liquid separator 6 and the second gas-liquid separator 5 respectively, and is used to detect the amount of hydrogen and carbon dioxide produced. The hydrogen and carbon dioxide output from the outlets of the first gas-liquid separator 6 and the second gas-liquid separator 5 can be used or stored in other processing stages.

[0100] The control element 10 is communicatively connected to the carbon dioxide load testing element 8 and the gas detection element 9, respectively. It is configured to determine the ratio of carbon dioxide to hydrogen produced based on the detected amounts of hydrogen and carbon dioxide, and to control the operating parameters of the electrolyzer 201 based on the determined carbon dioxide to hydrogen ratio and the carbon dioxide load in the regenerated absorbent. The operating parameters of the electrolyzer 201 may include, for example, the voltage of the electrolyzer 201, the flow rate of the carbon dioxide-rich solution, the current density of the electrolyzer 201, the operating temperature of the electrolyzer 201, and the cathode pressure of the electrolyzer 201.

[0101] In some embodiments, such as Figure 1 As shown, the anodic oxidation reaction carried out in the anode chamber 15 is an electrochemical oxygen evolution reaction, that is, the anode chamber 15 is configured to perform an electrochemical oxygen evolution reaction on water to produce hydrogen ions and oxygen. In this case, in some specific embodiments, the catalyst of the anode electrode is iridium dioxide supported on a gas diffusion electrode, and the catalyst of the cathode electrode is a platinum / carbon catalyst supported on a gas diffusion electrode.

[0102] like Figure 1 As shown, the electrochemical carbon dioxide desorption and absorbent regeneration apparatus 200 may further include a third gas-liquid separator 7, whose inlet and outlet are connected to the outlet and inlet of the anode chamber 15, respectively. This separator is used to separate the oxygen and water mixture from the anode chamber 15 into gas and liquid components, and to recycle the separated water (specifically deionized water) back into the anode chamber 15. The separated oxygen can be output through the gas outlet of the third gas-liquid separator 7.

[0103] In order to smoothly realize the circulation of water from the third gas-liquid separator 7 to the anode chamber 15, a third pumping device 4, such as a third transfer pump, can be installed between the liquid outlet of the third gas-liquid separator 7 and the liquid inlet of the anode chamber 15.

[0104] In other embodiments, such as Figure 2 As shown, the anodic oxidation reaction is an electrochemical hydrogen oxidation reaction. The inlet of the anode chamber 15 is connected to the outlet of the second gas-liquid separator 5. The anode chamber 15 is configured to perform an electrochemical oxidation reaction on the hydrogen separated from the second gas-liquid separator 5 to generate hydrogen ions. In this case, in some specific embodiments, the catalyst of the anode electrode is a platinum / carbon catalyst supported on a gas diffusion electrode, and the catalyst of the cathode electrode is a platinum / carbon catalyst supported on a gas diffusion electrode.

[0105] Figure 3 This is a schematic diagram illustrating the operating principle of a carbon dioxide capture system 100 coupled with electrolytic water electrolysis for hydrogen production according to an embodiment of the present invention, and its included electrochemical carbon dioxide desorption and absorbent regeneration apparatus 200, wherein an organic amine absorbent is used as an example. Figure 3This will enable those skilled in the art to better understand the operation of the electrochemical carbon dioxide desorption and absorbent regeneration apparatus 200 and the carbon dioxide capture system 100 coupled with water electrolysis for hydrogen production of the present invention.

[0106] Based on the same technical concept, the present invention also provides a carbon dioxide capture method coupled with water electrolysis for hydrogen production.

[0107] Figure 4 This is a schematic flowchart of a carbon dioxide capture method for hydrogen production via coupled water electrolysis according to an embodiment of the present invention. Figure 5 This is a schematic diagram of the specific process of a carbon dioxide capture method for hydrogen production by coupled water electrolysis according to an embodiment of the present invention.

[0108] Generally, after the gas to be treated absorbs carbon dioxide through the carbon dioxide absorption device 1, the purified gas is discharged. The resulting carbon dioxide-rich liquid is then desorbed through electrolysis to obtain carbon dioxide, hydrogen, and regenerated absorbent. The regenerated absorbent is returned to the carbon dioxide absorption device 1 for recycling.

[0109] The following is combined Figure 5 The process steps of the carbon dioxide capture method coupled with water electrolysis for hydrogen production are described.

[0110] See Figure 5 As shown, the carbon dioxide capture method coupled with water electrolysis for hydrogen production may include at least the following steps S502 to S506.

[0111] Step S502: Carbon dioxide is absorbed from the gas to be treated using an absorbent in the carbon dioxide absorption device 1 to obtain a carbon dioxide-rich liquid and purified gas.

[0112] Step S504: Electrolysis of carbon dioxide-rich liquid is performed using an electrochemical carbon dioxide desorption and absorbent regeneration method to desorb carbon dioxide and regenerate the absorbent, thereby obtaining carbon dioxide, hydrogen, and the regenerated absorbent.

[0113] This method for electrochemical carbon dioxide desorption and absorbent regeneration utilizes an electrochemical carbon dioxide desorption and absorbent regeneration apparatus 200. Specifically, it includes electrolyzing an input carbon dioxide-rich solution in an electrolytic cell 201 to obtain carbon dioxide, hydrogen, and regenerated absorbent in the cathode region of the electrolytic cell 201. During electrolysis, the ratio of obtained carbon dioxide to hydrogen and the carbon dioxide loading of the regenerated absorbent are adjusted by controlling the operating parameters of the electrolytic cell 201. The anodic reaction in the electrolytic cell 201 can be an electrochemical oxygen evolution reaction or an electrochemical hydrogen oxidation reaction.

[0114] The operating parameters of the electrolytic cell 201 may include at least one of the following: the voltage of the electrolytic cell 201, the current density of the electrolytic cell 201, the operating temperature of the electrolytic cell 201, and the cathode pressure of the electrolytic cell 201.

[0115] Step S506: At least a portion of the regenerated absorbent is recycled to the carbon dioxide absorption device 1 to absorb carbon dioxide.

[0116] In some embodiments, the ratio of carbon dioxide to hydrogen is 1:1 to 1:10, for example, 1:2, 1:3, 1:4, 1:5, 1:6, 1:7, 1:8, or 1:9; the carbon dioxide loading of the regenerated absorbent is 0 to 45% of the carbon dioxide loading of the carbon dioxide-rich solution, for example, 5%, 10%, 15%, 20%, 25%, 30%, or 35%.

[0117] In some embodiments, the voltage of the electrolytic cell 201 is 0-8V, and the current density of the electrolytic cell 201 is 100-20000A / m. 2 The operating temperature of electrolytic cell 201 is 20-100℃, and the cathode pressure of electrolytic cell 201 is between atmospheric pressure and 50 bar.

[0118] In some preferred embodiments, the absorbent may be the aforementioned organic amine absorbent.

[0119] The carbon dioxide capture method of the present invention, which is coupled with water electrolysis to produce hydrogen, utilizes an electrochemical carbon dioxide desorption and absorbent regeneration device 200 to perform electrochemical desorption of carbon dioxide and regeneration of the absorbent, thereby achieving a combination of high capture efficiency, high desorption rate and low desorption energy consumption. In particular, it makes it possible to industrialize high-concentration organic amines in the carbon dioxide absorption, electrochemical desorption and regeneration process, and has higher industrial application value.

[0120] The above introduces Figures 1 to 5 The embodiments shown have various implementation methods for each stage. The structure and operation of the carbon dioxide capture system 100 coupled with water electrolysis for hydrogen production of the present invention will be described in detail below through specific embodiments.

[0121] Example 1

[0122] The specific structure of the carbon dioxide capture system 100 coupled with water electrolysis for hydrogen production in Example 1 is as follows: Figure 1 As shown, the air-barrier membrane 18 is one of an asbestos membrane, a polyphenylene sulfide-based composite membrane, or a polymer porous membrane, and the solid filling medium 161 of the intermediate chamber 16 is a strong acid cation exchange resin.

[0123] During operation, air / combustion exhaust gas enters the carbon dioxide absorption unit 1 (absorption tower 1), contacts the absorbent and reacts. Purified air / combustion exhaust gas is discharged from the upper part of the absorption tower 1, and CO2-rich liquid flows out from the lower part. The CO2-rich liquid is pumped to the intermediate chamber 16 of the electrolytic cell 201 via the first pumping device 2 (rich liquid pump), where it reacts with H2 supplied by the anode chamber 15. +Electrochemical desorption of CO2 is performed. The desorbed CO2 and CO2-lean solution enter the first gas-liquid separator 6, where CO2 is collected. The CO2-lean solution is sent to the cathode chamber 14 of the electrolytic cell 201 for electrochemical hydrogen evolution and absorbent regeneration. The generated H2 and regenerated absorbent enter the second gas-liquid separator 5, where H2 is collected. The regenerated absorbent is pumped to the upper part of the absorption tower 1 via the second pumping device 3 (lean solution pump) for CO2 capture. Deionized water is pumped to the anode chamber 15 of the electrolytic cell 201 via the third pumping device 4 (water pump) for oxygen evolution reaction and to generate H2. + The O2 and water produced by the reaction enter the third gas-liquid separator 7, where the O2 is collected and the water is recycled.

[0124] Table 1 below lists the operating parameters of the carbon dioxide capture system 100 coupled with water electrolysis for hydrogen production in Example 1, wherein the thickness of the intermediate chamber 16 is 1.5 mm.

[0125] Table 1

[0126]

[0127] Table 2 below lists the performance parameters of the carbon dioxide capture system 100 coupled with water electrolysis for hydrogen production in Example 1.

[0128] Table 2

[0129]

[0130] Table 2 shows that, with the absorbent formulation of 3M MEA + 2M glycine + 2M KOH, and at a desorption temperature of 80℃, a current of 0.50A, and an electrode area of ​​5cm², the absorption rate is [data missing]. 2 Under operating parameters of 0.10 MPa cathode pressure and 5.6 mL / min CO2-rich solution flow rate, the optimal comprehensive effect of collection efficiency, desorption rate and desorption energy consumption can be achieved.

[0131] Comparative Example 1

[0132] The only difference between the carbon dioxide capture system of Comparative Example 1, which is a coupled water electrolysis hydrogen production system, and the carbon dioxide capture system 100 of Example 1, is that the gas barrier membrane 18 is replaced with a cation exchange membrane.

[0133] Table 3 below lists the operating parameters of the carbon dioxide capture system for hydrogen production via coupled water electrolysis in Comparative Example 1, where the thickness of the intermediate chamber is 1.5 mm.

[0134] Table 3

[0135]

[0136]

[0137] Table 4 below lists the performance parameters of the carbon dioxide capture system for hydrogen production via coupled water electrolysis in Comparative Example 1.

[0138] Table 4

[0139]

[0140] Example 2

[0141] The specific structure of the carbon dioxide capture system 100 coupled with water electrolysis for hydrogen production in Example 2 is as follows: Figure 2 As shown, the air-barrier membrane 18 is one of an asbestos membrane, a polyphenylene sulfide-based composite membrane, or a polymer porous membrane, and the solid filling medium 161 of the intermediate chamber 16 is a strong acid cation exchange resin.

[0142] During operation, air / combustion exhaust gas enters the carbon dioxide absorption unit 1 (absorption tower 1), contacts the absorbent and reacts. Purified air / combustion exhaust gas is discharged from the upper part of the absorption tower 1, and CO2-rich liquid flows out from the lower part. The CO2-rich liquid is pumped to the intermediate chamber 16 of the electrolytic cell 201 via the first pumping device 2 (rich liquid pump), where it reacts with H2 supplied by the anode chamber 15. + Electrochemical desorption of CO2 is performed. The desorbed CO2 and CO2-lean solution enter the first gas-liquid separator 6, where CO2 is collected. The CO2-lean solution is sent to the cathode chamber 14 of the electrolytic cell 201 for electrochemical hydrogen evolution and absorbent regeneration. The generated H2 and regenerated absorbent enter the second gas-liquid separator 5. The regenerated absorbent is pumped to the upper part of the absorption tower 1 via the second pumping device 3 (lean solution pump) for CO2 capture. The collected H2 is sent to the anode chamber 15 of the electrolytic cell 201 for hydrogen oxidation and to produce H2. + Thus, H2 is recycled.

[0143] Table 5 below lists the operating parameters of the carbon dioxide capture system 100 coupled with water electrolysis for hydrogen production in Example 2, wherein the thickness of the intermediate chamber 16 is 1.5 mm.

[0144] Table 5

[0145]

[0146]

[0147] Table 6 below lists the performance parameters of the carbon dioxide capture system 100 coupled with water electrolysis for hydrogen production in Example 2.

[0148] Table 6

[0149]

[0150] Table 6 shows that, with the absorbent formulation of 3M MEA + 2M glycine + 2M KOH, and at a desorption temperature of 80℃, a current of 0.50A, and an electrode area of ​​5cm², the absorption rate is [data missing]. 2 Under operating parameters of 0.10 MPa cathode pressure and 5.6 mL / min CO2-rich solution flow rate, the optimal comprehensive effect of collection efficiency, desorption rate and desorption energy consumption can be achieved.

[0151] Comparative Example 2

[0152] The only difference between the carbon dioxide capture system of Comparative Example 2, which is a coupled water electrolysis hydrogen production system, and the carbon dioxide capture system 100 of Example 2, is that the gas barrier membrane 18 is replaced with a cation exchange membrane.

[0153] Table 7 below lists the operating parameters of the carbon dioxide capture system for hydrogen production by coupled water electrolysis in Comparative Example 1, wherein the thickness of the intermediate chamber 16 is 1.5 mm.

[0154] Table 7

[0155]

[0156] Table 8 below lists the performance parameters of the carbon dioxide capture system for hydrogen production via coupled water electrolysis in Comparative Example 2.

[0157] Table 8

[0158]

[0159] Experimental data show that the carbon dioxide capture system 100 of the present invention coupled with water electrolysis for hydrogen production has significantly better capture efficiency, desorption rate and desorption energy consumption than the carbon dioxide capture system of the prior art that uses a cation exchange membrane to separate the intermediate chamber and the cathode chamber for water electrolysis for hydrogen production.

[0160] Numerous specific details are set forth in the specification provided herein. However, it will be understood that embodiments of the invention may be practiced without these specific details. In some instances, well-known methods, structures, and techniques have not been shown in detail so as not to obscure the understanding of this specification.

[0161] Therefore, those skilled in the art should recognize that although numerous exemplary embodiments of the present invention have been shown and described in detail herein, many other variations or modifications conforming to the principles of the present invention can be directly determined or derived from the disclosure of the present invention without departing from the spirit and scope of the invention. Thus, the scope of the present invention should be understood and construed as covering all such other variations or modifications.

Claims

1. An apparatus for electrochemical carbon dioxide desorption and absorbent regeneration, comprising an electrolytic cell, characterized in that, The electrolytic cell includes at least one stacked electrolytic cell, each of the electrolytic cells comprising: The anode chamber, located in the anode region, is configured to undergo an anodic oxidation reaction to generate hydrogen ions; and A cathode chamber and an intermediate chamber are located in the cathode region. The intermediate chamber is located between the anode chamber and the cathode chamber. The intermediate chamber is configured to allow the input carbon dioxide-rich solution to react with hydrogen ions from the anode chamber to electrochemically desorb carbon dioxide, thereby producing carbon dioxide and a carbon dioxide-poor solution. The cathode chamber is configured to receive the carbon dioxide-poor solution from the intermediate chamber and cause the carbon dioxide-poor solution to undergo electrochemical hydrogen evolution to produce hydrogen gas and a regenerated absorbent. The anode chamber is separated from the intermediate chamber by a cation exchange membrane, and the intermediate chamber is separated from the cathode chamber by a gas-barrier membrane, which is configured to isolate gases but allow cations and water to pass through it.

2. The apparatus for electrochemical carbon dioxide desorption and absorbent regeneration according to claim 1, characterized in that, The air-barrier membrane is an asbestos membrane, a polyphenylene sulfide-based composite membrane, or a polymer porous membrane. The cation exchange membrane is a proton exchange membrane.

3. The apparatus for electrochemical carbon dioxide desorption and absorbent regeneration according to claim 2, characterized in that, The asbestos membrane is a polytetrafluoroethylene resin modified asbestos membrane. The polymer porous membrane is a polyetheretherketone porous membrane or a polysulfone porous membrane.

4. The apparatus for electrochemical carbon dioxide desorption and absorbent regeneration according to claim 1, characterized in that, The thickness of the intermediate chamber is in the range of 0.1 mm to 5.0 mm; The intermediate chamber is filled with a solid filling medium, the porosity of which is 10%-90%.

5. The apparatus for electrochemical carbon dioxide desorption and absorbent regeneration according to claim 4, characterized in that, The solid filling medium is one or more of the following: metal mesh, foamed metal, foamed ceramic, plastic mesh, porous plastic, ceramic microspheres, glass microspheres, polymer microspheres, cation exchange resin, and anion exchange resin.

6. The apparatus for electrochemical carbon dioxide desorption and absorbent regeneration according to any one of claims 1-5, characterized in that, The electrolytic cell is provided with a cathode end plate and an anode end plate at both ends. The two adjacent electrolytic cells inside the electrolytic cell are separated by bipolar plates. An anode electrode and a cathode electrode are closely distributed on both sides of each bipolar plate.

7. The apparatus for electrochemical carbon dioxide desorption and absorbent regeneration according to claim 6, characterized in that, Also includes: A rich liquid input element is connected to the inlet of the intermediate chamber and is used to deliver the carbon dioxide rich liquid into the intermediate chamber through the inlet of the intermediate chamber. The first gas-liquid separator has its inlet and outlet connected to the outlet of the intermediate chamber and the inlet of the cathode chamber, respectively, for gas-liquid separation of the mixed fluid of carbon dioxide and carbon dioxide-lean liquid from the intermediate chamber, and for conveying the separated carbon dioxide-lean liquid into the cathode chamber. as well as The second gas-liquid separator has its inlet connected to the outlet of the cathode chamber for gas-liquid separation of the mixed fluid of hydrogen and regenerated absorbent from the cathode chamber. The outlet of the second gas-liquid separator is configured to be connected to an external carbon dioxide absorption device so that the separated regenerated absorbent can be output to the carbon dioxide absorption device through the outlet of the second gas-liquid separator.

8. The apparatus for electrochemical carbon dioxide desorption and absorbent regeneration according to claim 7, characterized in that, Also includes: A carbon dioxide loading test element is connected to the outlet of the second gas-liquid separator and is used to detect the carbon dioxide loading in the regenerated absorbent output from the outlet of the second gas-liquid separator. A gas detection element is connected to the outlet of the first gas-liquid separator and the second gas-liquid separator respectively, and is used to detect the amount of hydrogen and carbon dioxide produced; as well as The control element is communicatively connected to the carbon dioxide load testing element and the gas detection element, respectively, and is configured to determine the ratio of carbon dioxide to hydrogen produced based on the detected amounts of hydrogen and carbon dioxide, and control the operating parameters of the electrolyzer based on the determined ratio of carbon dioxide to hydrogen and the carbon dioxide load in the regenerated absorbent.

9. The apparatus for electrochemical carbon dioxide desorption and absorbent regeneration according to claim 6, characterized in that, The anodic oxidation reaction is an electrochemical oxygen evolution reaction, and the anode chamber is configured to perform an electrochemical oxygen evolution reaction on water to generate hydrogen ions and oxygen. The catalyst for the anode electrode is iridium dioxide supported on a gas diffusion electrode, and the catalyst for the cathode electrode is a platinum / carbon catalyst supported on a gas diffusion electrode. The device further includes: The third gas-liquid separator has its inlet and outlet connected to the outlet and inlet of the anode chamber, respectively. It is used to separate the mixed fluid of oxygen and water from the anode chamber into gas and liquid, and to input the separated water back into the anode chamber for recycling.

10. The apparatus for electrochemical carbon dioxide desorption and absorbent regeneration according to claim 7, characterized in that, The anodic oxidation reaction is an electrochemical hydrogen oxidation reaction. The inlet of the anode chamber is connected to the outlet of the second gas-liquid separator. The anode chamber is configured to perform an electrochemical oxidation reaction on the hydrogen separated from the second gas-liquid separator to generate hydrogen ions. The catalyst for the anode electrode is a platinum / carbon catalyst supported on a gas diffusion electrode, and the catalyst for the cathode electrode is a platinum / carbon catalyst supported on a gas diffusion electrode.

11. A carbon dioxide capture system coupled with water electrolysis for hydrogen production, comprising: A carbon dioxide absorption device is configured to absorb carbon dioxide from a gas to be treated using an absorbent, thereby obtaining a carbon dioxide-rich liquid and purified gas. The feature is that it further includes an apparatus for electrochemical carbon dioxide desorption and absorbent regeneration according to any one of claims 1-10; The rich solution outlet and the lean solution inlet of the carbon dioxide absorption device are respectively connected to the electrochemical carbon dioxide desorption and absorbent regeneration device. The carbon dioxide absorption device is configured to input the carbon dioxide rich solution into the electrochemical carbon dioxide desorption and absorbent regeneration device through the rich solution outlet, and to receive the regenerated absorbent from the electrochemical carbon dioxide desorption and absorbent regeneration device through the lean solution inlet. The absorbent is an organic amine absorbent.

12. A method for electrochemical carbon dioxide desorption and absorbent regeneration, characterized in that, The method is carried out using the apparatus for electrochemical carbon dioxide desorption and absorbent regeneration according to any one of claims 1-10, and the method comprises: The input carbon dioxide-rich solution is electrolyzed in the electrolytic cell to obtain carbon dioxide, hydrogen, and regenerated absorbent in the cathode region of the electrolytic cell. During the electrolysis process, the ratio of carbon dioxide and hydrogen obtained and the carbon dioxide loading of the regenerated absorbent are adjusted by controlling the operating parameters of the electrolytic cell. The operating parameters of the electrolytic cell include at least one of the following: the voltage of the electrolytic cell, the current density of the electrolytic cell, the operating temperature of the electrolytic cell, and the cathode pressure of the electrolytic cell.

13. The method for electrochemical carbon dioxide desorption and absorbent regeneration according to claim 12, characterized in that, The ratio of carbon dioxide to hydrogen is 1:1 to 1:10, and the carbon dioxide loading of the regenerated absorbent is 0 to 45% of the carbon dioxide loading of the carbon dioxide-rich solution. The voltage of the electrolytic cell is 0-8V, and the current density of the electrolytic cell is 100-20000A / m. 2 The operating temperature of the electrolytic cell is 20-100℃, and the cathode pressure of the electrolytic cell is between atmospheric pressure and 50 bar.

14. A carbon dioxide capture method coupled with water electrolysis for hydrogen production, characterized in that, include: Carbon dioxide is absorbed from the gas to be treated using an absorbent in a carbon dioxide absorption device to obtain a carbon dioxide-rich liquid and purified gas. The carbon dioxide-rich solution is electrolyzed using the electrochemical carbon dioxide desorption and absorbent regeneration method according to claim 12 or 13 to desorb carbon dioxide and regenerate the absorbent, thereby obtaining carbon dioxide, hydrogen, and the regenerated absorbent. At least a portion of the regenerated absorbent is recycled back into the carbon dioxide absorption device to absorb carbon dioxide.

15. The carbon dioxide capture method for coupled water electrolysis to produce hydrogen according to claim 14, characterized in that, The absorbent is an organic amine absorbent, comprising: 20-30 wt.% of a main solvent, 4-8 wt.% of a first auxiliary additive, 4-8 wt.% of a second auxiliary additive, and the balance being water; The main solvent is an organic amine compound, the first auxiliary additive is an amino acid, and the second auxiliary additive is a hydroxide.

16. The carbon dioxide capture method for hydrogen production via coupled water electrolysis according to claim 15, characterized in that, The organic amine compound is one or more selected from ethanolamine, N-methyldiethanolamine, isopropanolamine, piperazine, and hydroxyethylpiperazine; The amino acid is one or more selected from glycine, proline, D-alanine, 2-aminoisobutyric acid, sarcosine, D-2-aminobutyric acid, and taurine. The hydroxide is potassium hydroxide and / or sodium hydroxide.

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