MEA electrolytic bath device and method for electrocatalytic carbon dioxide reduction

Abstract

According to the MEA electrolytic cell device and method for electrocatalytic carbon dioxide reduction, in the device, a left-end negative plate and a right-end negative plate are connected with a direct-current power source cathode; the middle anode plate is arranged in the center of the device and connected with a direct-current power anode; the multiple small electrolysis chambers are axially and symmetrically arranged on the two sides of the middle anode plate and are divided into a left group and a right group, the small electrolysis chambers in each group are connected in series in a circuit to form a left side integrated electrolysis chamber and a right side integrated electrolysis chamber, and the left side integrated electrolysis chamber and the right side integrated electrolysis chamber are electrically isolated through the middle anode plate. The electrolysis cells are connected in parallel in an external circuit to form a series-parallel cooperative circuit structure, each electrolysis cell comprises a cathode and anode composite plate, a composite plate insulating spacer, a cathode gas diffusion layer, a membrane electrode and an anode catalytic electrode, one side of each cathode and anode composite plate is a cathode surface, and the other side of each cathode and anode composite plate is an anode surface for accommodating a cathode assembly and an anode assembly respectively; and the cathode and anode composite plate is provided with a diagonal hole flow channel.

Description

Technical Field

[0001] This invention relates to the field of electrocatalytic carbon dioxide reduction technology, and in particular to an MEA electrolyzer device for electrocatalytic carbon dioxide reduction. Background Technology

[0002] As one of the core pathways for realizing the utilization of carbon resources, the industrial application of electrolytic carbon dioxide (CO2) reduction technology has become a research focus. This technology converts CO2 into high-value chemicals such as CO, formic acid, and ethylene through electrocatalytic reactions, and can be directly coupled with renewable energy sources such as photovoltaics and wind power to build a "zero-carbon" circular system, which is of great strategic significance for promoting the development of the green chemical industry.

[0003] Among various CO2 electrolysis devices, MEA (membrane electrode assembly) electrolyzers, due to their integration of gas diffusion electrodes (GDE) and ion exchange membranes, possess high mass transfer efficiency, excellent Faraday efficiency, and can operate at high current densities (>100 mA·cm⁻¹). -2 The advantages of stable operation under various conditions make it a technology route with the greatest potential for industrialization. However, the development of existing MEA electrolyzers still faces bottlenecks in scaling up: laboratory-scale devices are mostly single-cell designs, but single-cell designs are limited by electrode area and power output, making it difficult to meet the industrial production demand for tons / day of product. Traditional scale-up approaches (such as simply increasing the electrode area or connecting multiple cells in series) have significant drawbacks—an excessively large single-cell area leads to uneven flow field distribution and large differences in local current density, causing catalyst deactivation and membrane degradation. At the same time, the series connection will superimpose cell voltage, significantly increasing energy consumption, and a single-cell failure will cause the entire system to shut down, resulting in extremely poor stability.

[0004] The information disclosed in the background section is only intended to enhance the understanding of the background of the present invention, and therefore may contain information that does not constitute prior art known to those skilled in the art. Summary of the Invention

[0005] To address the shortcomings or defects of the existing technology, an MEA electrolyzer device for electrocatalytic carbon dioxide reduction is provided. The high-power series-parallel synergistic MEA electrolyzer device solves the problems of limited power in existing devices and current-voltage imbalance in traditional series-parallel connection methods, thereby improving carbon dioxide conversion efficiency and product yield, and reducing costs.

[0006] The objective of this invention is achieved through the following technical solutions.

[0007] An MEA electrolyzer device for electrocatalytic carbon dioxide reduction includes,

[0008] The left and right negative plates are respectively connected to the cathodes of the DC power supply;

[0009] The intermediate anode plate is located in the center of the device and is connected to the DC power supply anode;

[0010] Multiple electrolytic cells are symmetrically arranged along the axial direction on both sides of a central anode plate. These cells are divided into two groups, left and right. The cells within each group are connected in series in the circuit, forming a left integrated electrolytic cell and a right integrated electrolytic cell. The left and right integrated electrolytic cells are electrically isolated by the central anode plate and connected in parallel in the external circuit, forming a series-parallel coordinated circuit structure. Each electrolytic cell includes an anode-cathode composite plate, an insulating gasket for the composite plate, a cathode gas diffusion layer, a membrane electrode, and an anode catalytic electrode. One side of the anode-cathode composite plate is the cathode surface, and the other side is the anode surface, respectively accommodating the cathode and anode components. The anode-cathode composite plate has diagonally opposite aperture channels. The aperture below the cathode surface is the CO2 inlet channel, and the aperture above the cathode surface is the outlet channel for the mixture of cathode products and unreacted CO2. The aperture below the anode surface is the electrolyte inlet channel, and the aperture above the anode surface is the outlet channel for the mixture of O2 and electrolyte.

[0011] The MEA electrolyzer for electrocatalytic carbon dioxide reduction also includes,

[0012] The left and right end pressure plates are arranged at intervals to serve as structural support and sealing end caps.

[0013] The left end pressure plate insulating sealing gasket and the right end pressure plate insulating sealing gasket are respectively connected to the left end pressure plate and the right end pressure plate to provide electrical insulation and gas-liquid sealing between the end plate and the metal electrode plate.

[0014] The MEA electrolyzer for electrocatalytic carbon dioxide reduction also includes a pair of fastening devices for overall clamping and stress buffering, respectively located on the outside of the left and right negative electrode plates. The fastening devices include a tension bolt, a nut, a disc spring seat, a disc spring, a disc spring guide sleeve, and an insulating guide sleeve. The insulating guide sleeve is fitted onto the tension bolt, and the disc spring guide sleeve, disc spring, disc spring seat, and nut are sequentially assembled on the outside of the left or right negative electrode plate on the tension bolt.

[0015] In the MEA electrolyzer device for electrocatalytic carbon dioxide reduction, the anode-cathode composite plate includes a left anode-cathode composite plate A and a right anode-cathode composite plate B, which are axially symmetrical with respect to the middle anode plate.

[0016] In the MEA electrolyzer device for electrocatalytic carbon dioxide reduction, the membrane electrode is integrated with a cathode electrode, a cathode catalyst layer and an ion exchange membrane using a zero-gap structure. The carbon black layer of the cathode electrode is directly and physically bonded to the ion exchange membrane, and the cathode catalyst layer is loaded on the surface of the carbon black layer or the ion exchange membrane.

[0017] In the MEA electrolyzer device for electrocatalytic carbon dioxide reduction, the cathode catalyst layer uses a nickel-based catalyst or a silver-based catalyst. The cathode catalyst layer is composited on the carbon black layer of the cathode carbon paper electrode or on one side of the ion exchange membrane by means of loading such as spraying.

[0018] In the MEA electrolyzer device for electrocatalytic carbon dioxide reduction, the cathode electrode is a carbon paper electrode, with one side of the carbon paper composited with the cathode gas diffusion layer and the other side being a carbon black layer composite ion exchange membrane.

[0019] In the MEA electrolyzer device for electrocatalytic carbon dioxide reduction, the cathode gas diffusion layer is a composite laminated integrated structure of nickel foam-nickel mesh-nickel felt, and the porosity of the cathode gas diffusion layer is >90%.

[0020] In the MEA electrolytic cell device for electrocatalytic carbon dioxide reduction, an electrocatalytic CO2 reduction reaction occurs in the cathode chamber of the electrolysis chamber to generate CO, and an oxidation reaction occurs in the anode chamber of the electrolysis chamber to generate O2.

[0021] The electrocatalytic carbon dioxide reduction method of the MEA electrolyzer device includes,

[0022] S1: The MEA electrolytic cell device is subjected to a pressure holding test at 0.1–0.5 MPa for ≥24 hours;

[0023] S2: CO2 gas is introduced to the cathode side, entering the cathode gas diffusion layer through diagonally opposite inlet channels. A CO2 reduction reaction occurs in the cathode catalytic layer, producing CO or C. 2+ The product, along with unreacted CO2, is discharged from the vent.

[0024] S3: Alkaline, acidic or neutral electrolyte is introduced into the anode side and enters the anode catalytic electrode through the inlet channel, where a water oxidation reaction occurs to generate O2. O2 and electrolyte are discharged from the outlet channel.

[0025] S4: When a DC power supply applies voltage, the voltages of the integrated electrolysis chambers on the left and right sides are superimposed through series connection, and then current is shunted through parallel connection to form a series-parallel coordinated power supply mode.

[0026] S5: The product is collected by the separation system to realize the resource utilization of CO2.

[0027] Compared with existing technologies, the beneficial effects of this invention are as follows: Through an innovative series-parallel collaborative design, this invention balances high power output with system stability. By cleverly optimizing circuit connections and flow field layout, it ensures a balanced distribution of current and voltage among each MEA unit, significantly improving current density and energy utilization efficiency. Simultaneously, its flexible modular architecture allows for easy scaling up based on actual production needs, greatly enhancing adaptability to different industrial scenarios. This invention can improve carbon dioxide conversion efficiency and product yield, effectively reduce production costs, significantly enhance the competitiveness of electrocatalytic carbon dioxide reduction technology in the industrial field, and promote the industrialization of CO2 electrolysis technology.

[0028] The description provided is merely an overview of the technical solution of this invention. In order to make the technical means of this invention clearer and more understandable, so that those skilled in the art can implement it according to the contents of the specification, and to make the described and other objects, features and advantages of this invention more obvious and understandable, specific embodiments of this invention are described below. Attached Figure Description

[0029] Various other advantages and benefits of the present invention will become apparent to those skilled in the art upon reading the detailed description of the preferred embodiments below. The accompanying drawings are for illustrative purposes only and are not intended to limit the invention. It is obvious that the drawings described below are merely some embodiments of the invention, and those skilled in the art can obtain other drawings based on these drawings without any inventive effort. Furthermore, the same reference numerals denote the same parts throughout the drawings.

[0030] In the attached diagram:

[0031] Figure 1 This is a schematic diagram of the MEA electrolytic cell device according to an embodiment of the present invention;

[0032] Figure 2 This is an assembly diagram of the electrolysis chamber according to an embodiment of the present invention;

[0033] Figure 3 This is a schematic diagram of the flow channel of the MEA electrolytic cell device according to an embodiment of the present invention.

[0034] The present invention will be further explained below with reference to the accompanying drawings and embodiments. Detailed Implementation

[0035] Specific embodiments of the invention will now be described in more detail with reference to the accompanying drawings. While specific embodiments of the invention are shown in the drawings, it should be understood that the invention can be implemented in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided to enable a more thorough understanding of the invention and to fully convey the scope of the invention to those skilled in the art.

[0036] It should be noted that certain terms are used in the specification and claims to refer to specific components. Those skilled in the art will understand that different terms may be used to refer to the same component. This specification and claims do not distinguish components based on differences in terminology, but rather on differences in function. The terms "comprising" or "including" used throughout the specification and claims are open-ended and should be interpreted as "comprising but not limited to." The following descriptions are preferred embodiments for carrying out the invention; however, these descriptions are for the purpose of understanding the general principles of the specification and are not intended to limit the scope of the invention. The scope of protection of this invention is determined by the appended claims.

[0037] To facilitate understanding of the embodiments of the present invention, the following will provide further explanation and description with reference to the accompanying drawings and several specific embodiments, and the accompanying drawings do not constitute a limitation on the embodiments of the present invention.

[0038] To better understand, such as Figures 1 to 3 As shown, a MEA electrolyzer device for electrocatalytic carbon dioxide reduction includes,

[0039] The left negative plate 9 and the right negative plate 14 are respectively connected to the cathode of the DC power supply.

[0040] The intermediate anode plate 12 is located in the center of the device and is connected to the DC power supply anode;

[0041] Multiple electrolytic cells are symmetrically arranged along the axial direction on both sides of the central anode plate. The multiple electrolytic cells are divided into two groups, left and right. The electrolytic cells in each group are connected in series in the circuit to form a left integrated electrolytic cell and a right integrated electrolytic cell. The left integrated electrolytic cell and the right integrated electrolytic cell are electrically isolated by the central anode plate 12 and connected in parallel in the external circuit to form a series-parallel cooperative circuit structure. The electrolytic cell includes an anode-cathode composite plate, a composite plate insulating gasket 10-1, a cathode gas diffusion layer 10-2, a membrane electrode, and an anode catalytic electrode 10-5. One side of the anode-cathode composite plate is the cathode surface 17-1, and the other side is the anode surface 17-2, which respectively accommodate the cathode and anode components. The anode-cathode composite plate is provided with diagonally opposite aperture channels. The hole below the cathode surface is the CO2 inlet channel c, and the hole above the cathode surface is the outlet channel a for the mixture of cathode products and unreacted CO2. The hole below the anode surface is the electrolyte inlet channel d, and the hole above the anode surface is the outlet channel b for the mixture of O2 and electrolyte.

[0042] In a preferred embodiment of the MEA electrolyzer for electrocatalytic carbon dioxide reduction, the device further includes,

[0043] The left end pressure plate 7 and the right end pressure plate 16 are arranged at intervals relative to each other to serve as structural support and sealing end caps.

[0044] The left end pressure plate insulating sealing gasket 8 and the right end pressure plate insulating sealing gasket 15 are respectively connected to the left end pressure plate 7 and the right end pressure plate 16 to provide electrical insulation and gas-liquid sealing between the end plate and the metal electrode plate.

[0045] In a preferred embodiment of the MEA electrolyzer for electrocatalytic carbon dioxide reduction, a pair of fastening devices for overall clamping and stress buffering are further provided on the outer sides of the left negative electrode plate 9 and the right negative electrode plate 14. The fastening devices include a tension bolt 1, a nut 2, a disc spring seat 3, a disc spring 4, a disc spring guide sleeve 5, and an insulating guide sleeve 6. The insulating guide sleeve 6 is fitted onto the tension bolt 1. The disc spring guide sleeve 5, the disc spring 4, the disc spring seat 3, and the nut 2 are sequentially assembled on the outer side of the left negative electrode plate 9 or the right negative electrode plate 14 on the tension bolt 1.

[0046] In a preferred embodiment of the MEA electrolyzer for electrocatalytic carbon dioxide reduction, the anode-cathode composite plate includes a left anode-cathode composite plate A11 and a right anode-cathode composite plate B13, which are axially symmetrical with respect to the middle anode plate 12.

[0047] In a preferred embodiment of the MEA electrolyzer for electrocatalytic carbon dioxide reduction, the membrane electrode is integrated with a zero-gap structure consisting of a cathode electrode 10-3, a cathode catalyst layer, and an ion exchange membrane 10-4. The carbon black layer of the cathode electrode 10-3 is directly and physically bonded to the ion exchange membrane 10-4, and the cathode catalyst layer is loaded on the surface of the carbon black layer or the ion exchange membrane.

[0048] In a preferred embodiment of the MEA electrolyzer for electrocatalytic carbon dioxide reduction, the cathode catalyst layer is a nickel-based catalyst or a silver-based catalyst, and the cathode catalyst layer is composited on the carbon black layer of the cathode carbon paper electrode or on one side of the ion exchange membrane by means of spraying or other loading methods.

[0049] In a preferred embodiment of the MEA electrolyzer for electrocatalytic carbon dioxide reduction, the cathode electrode 10-3 is a carbon paper electrode, with one side of the carbon paper composited with the cathode gas diffusion layer 10-2 and the other side being a carbon black layer composite ion exchange membrane.

[0050] In a preferred embodiment of the MEA electrolyzer for electrocatalytic carbon dioxide reduction, the cathode gas diffusion layer 10-2 is a composite laminated integrated structure of nickel foam-nickel mesh-nickel felt, and the porosity of the cathode gas diffusion layer is >90%.

[0051] In a preferred embodiment of the MEA electrolyzer for electrocatalytic carbon dioxide reduction, an electrocatalytic CO2 reduction reaction occurs in the cathode chamber of the electrolysis chamber to generate CO, and an oxidation reaction occurs in the anode chamber of the electrolysis chamber to generate O2.

[0052] The electrocatalytic carbon dioxide reduction method of the MEA electrolyzer device includes,

[0053] S1: The MEA electrolytic cell device is subjected to a pressure holding test at 0.1–0.5 MPa for ≥24 hours;

[0054] S2: CO2 gas is introduced to the cathode side, entering the cathode gas diffusion layer 10⁻² through the diagonally opposite inlet channel c. A CO2 reduction reaction occurs in the cathode catalyst layer, producing CO or C. 2+ The product, along with unreacted CO2, is discharged from outlet a.

[0055] S3: Alkaline, acidic or neutral electrolyte is introduced into the anode side and enters the anode catalytic electrode 10-5 through the inlet channel d, where a water oxidation reaction occurs to generate O2. O2 and electrolyte are discharged from the outlet channel b.

[0056] S4: When a DC power supply applies voltage, the voltages of the integrated electrolysis chambers on the left and right sides are superimposed through series connection, and then current is shunted through parallel connection to form a series-parallel coordinated power supply mode.

[0057] S5: The product is collected by the separation system to realize the resource utilization of CO2.

[0058] In one embodiment, the MEA electrolytic cell device comprises core components such as left and right end pressure plates, left and right end pressure plate insulating and sealing gaskets, left and right negative electrode plates, a middle anode plate, electrolysis chambers, and fastening devices; the high-power series-parallel coordinated MEA electrolytic cell device adopts a horizontal structure, with a designed rated operating power of 10kW, and the operating power is adjustable within the range of 0-10kW; the pressure inside the MEA electrolytic cell device is adjustable from 0-0.5MPa, the pressure on the anode and cathode sides should be balanced, and the temperature is adjustable from room temperature to 80℃; the high-power series-parallel coordinated MEA electrolytic cell device is composed of 40 electrolysis chambers connected in a series-parallel coordinated manner; the MEA electrolytic cell device adopts a left... The electrolytic cell is symmetrically assembled on the left and right sides. Twenty electrolytic cells are connected in series on each side to form integrated electrolytic cells. These integrated electrolytic cells are separated by a central anode plate, and the two integrated electrolytic cells are connected in parallel. The MEA electrolytic cell device is assembled sequentially with the left end pressure plate 7, the left end pressure plate insulating gasket 8, the left end negative electrode plate 9, and the electrolytic cells, 20 electrolytic cells in total. The electrolytic cell anode plate 12 is placed in the middle. The right-side electrolytic cells are symmetrically assembled with the left-side cells, 20 electrolytic cells, the right end negative electrode plate 14, the right end pressure plate insulating gasket 15, and the right end pressure plate 16 in total, 20 electrolytic cells in total, the right end negative electrode plate 14, the right end pressure plate insulating gasket 15, and the right end pressure plate 16 in total. Finally, the electrolytic cell is secured using fastening devices, and the assembly is complete.

[0059] Preferably, the left and right end pressure plates are designed with a diameter of Φ415mm. 50mm; the left and right end pressure plate insulating sealing gaskets are designed with an outer diameter of Φ307mm, an inner diameter of Φ228mm, and a thickness of 2mm; the left and right end negative electrode plates are designed with a diameter of Φ306mm. 6.5mm; the anode and cathode composite plate is designed to be Φ306mm. 6.5mm; the intermediate anode plate is designed to be Φ306mm. 9.5mm;

[0060] Preferably, the left and right end pressure plates, left and right end negative electrode plates, middle anode plate, and anode-cathode composite plate are made of Q235B carbon steel with nickel plating; the metal electrode plates are designed to withstand acids and alkalis, with a designed operating cycle of at least 15 years in an environment with pH=0-14, and the designed operating voltage of the metal electrode plates is not less than 3.2V DC voltage; the left and right end negative electrode plates are connected to the cathode of the DC power supply, and the middle anode plate is connected to the anode of the DC power supply; the electrolysis chamber includes an integrated electrolysis chamber assembly 10 and an anode-cathode composite plate, as shown in the assembly diagram. Figure 2As shown, the electrolysis chamber integrated assembly 10 includes a composite plate insulating gasket 10-1, a cathode gas diffusion layer 10-2, a membrane electrode and an anode catalytic electrode 10-5; the membrane electrode is prepared by physical integration of a cathode electrode 10-3, a cathode catalytic layer and an ion exchange membrane 10-4 using a zero-gap structure; one side of the anode-cathode composite plate is a cathode surface 17-1, and the other side is an anode surface 17-2. Both the anode and cathode surfaces adopt an inner groove design. The groove on the cathode surface can accommodate the cathode gas diffusion layer, and the groove on the anode surface can accommodate the anode catalytic electrode. Both the anode and cathode surfaces are designed with diagonally opposite aperture flow channels; the anode-cathode composite plate is divided into A / B plates, which are axially symmetrically designed. The electrolysis chamber on the left side of the middle anode plate adopts the anode-cathode composite plate A11, and the electrolysis chamber on the right side adopts the anode-cathode composite plate B13.

[0061] Preferably, the groove depth of the anode-cathode composite plate is 2.2 mm; the cathode surface of the anode-cathode composite plate has 17-1 diagonally spaced flow channels, and the flow channels are arranged as follows: Figure 3 As shown, the hole below the cathode surface is a CO2 inlet channel (c), and the hole above the cathode surface is an outlet channel (a) for the mixture of cathode products and unreacted CO2. The hole below the anode surface is an electrolyte inlet channel (d), and the hole above the anode surface is an outlet channel (b) for the mixture of O2 and electrolyte. The composite plate insulating gasket 10-1 is located between the anode-cathode composite plate and the membrane electrode, buffering the stress compression between the ion exchange membrane and the anode-cathode composite plate. Preferably, the composite plate insulating gasket is an imported polytetrafluoroethylene gasket with an outer diameter of Φ307mm, an inner diameter of Φ228mm, and a thickness of 0.5mm. The cathode gas diffusion layer 10-2 adopts a composite laminated integrated structure of nickel foam, nickel mesh, and nickel felt, with a porosity of 97%. Preferably, the cathode gas diffusion layer has a design specification of Φ228mm. 2mm; the cathode catalytic layer uses a nickel-based catalyst, and the target reduction product is CO. The cathode catalytic layer is composited onto the carbon black layer of the cathode carbon paper electrode by spraying and loading; the cathode electrode 10-3 is a carbon paper electrode, with one side of the carbon paper composited with the cathode gas diffusion layer, and the other side being a carbon black layer composite ion exchange membrane; preferably, the cathode carbon paper electrode is designed with a diameter of Φ228mm. 0.2mm; The ion exchange membrane 10-4 adopts an AEM anion exchange membrane, which divides the electrolysis chamber into a cathode chamber and an anode chamber. The ion exchange membrane is designed to operate at a voltage of not less than 3.2V DC. In the cathode chamber, an electrocatalytic CO2 reduction reaction occurs to generate CO; in the anode chamber, an oxidation reaction occurs to generate O2. The fastening devices include a tension bolt 1, a nut 2, a disc spring seat 3, a disc spring 4, a disc spring guide sleeve 5, and an insulating guide sleeve 6. After the electrolytic cell is assembled, on the left... A tension bolt 1 is inserted into the right end pressure plate, and an insulating guide sleeve 6 is fitted onto the tension bolt. Disc spring guide sleeves 5, disc springs 4, disc spring seats 3, and nuts 2 are sequentially assembled on the outer sides of the left and right end pressure plates onto the tension bolt. A torque wrench is used to tighten the tension bolt on the nut, completing the assembly of the high-power series-parallel coordinated MEA electrolytic cell device. After the assembly of the high-power series-parallel coordinated MEA electrolytic cell device is completed, the electrolytic cell is subjected to a pressure holding test at 0.5 MPa for 24 hours. There is no air leakage or internal flow within the flow channels of the electrolytic cell device, indicating good airtightness and meeting the operational requirements.

[0062] Furthermore, the series-parallel coordinated circuit structure of this invention (series connection on both sides + parallel connection in the middle) achieves a unified approach to voltage superposition and current shunting, solving problems such as low single-cell power, high voltage in series connection, and uneven current in parallel connection in traditional electrolytic cells, thereby improving overall power and stability. The symmetrical integrated electrolytic chamber design ensures consistency in flow field, current, and voltage drop on both sides, avoiding imbalance between parallel branches, preventing local overload or uneven reaction, and improving system operational stability. The A / B axis symmetrical design of the anode and cathode composite plates optimizes the symmetry of the flow channels and electrodes, ensuring symmetry of the integrated electrolytic chambers in terms of flow channel direction, electrode layout, and assembly stress, reducing structural deviations. The zero-gap membrane electrode integrated structure reduces interfacial contact resistance, improves electron and ion transport efficiency, and enhances electrochemical reaction rate and energy efficiency. The cathode gas diffusion layer (foamed nickel-nickel mesh-nickel felt composite structure) enhances CO2 mass transfer and electron conduction capabilities, improves CO2 reduction reaction efficiency, promotes gas-liquid-solid three-phase interfacial reaction, and improves product selectivity and current density. The diagonally angled orifice design (CO2 inlet / outlet, electrolyte inlet / outlet) optimizes gas and liquid flow distribution, avoids dead zones, improves mass transfer efficiency, reduces local concentration polarization, and enhances reaction uniformity. Corrosion-resistant metal plates (Q235B nickel-plated) improve acid and alkali resistance and voltage withstand performance, ensuring long-term stable operation of the electrolyzer in pH 0–14 environments and extending its service life to over 10 years. Composite plate insulating gaskets (PTFE) buffer stress between the ion exchange membrane and the composite plate, preventing membrane damage under pressure and improving sealing and long-term operational reliability. Ion exchange membranes (AEM / CEM) separate the anode and cathode reaction chambers, selectively transporting ions to ensure normal electrolysis, while also possessing high voltage withstand capability (≥3.2V) to prevent breakdown and ion back migration. The cathode catalyst layer (nickel-based / silver-based catalyst) catalyzes the reduction of CO2 to CO, other single C or C2C atoms. 2+The product enhances CO2 conversion rate and product selectivity, improving the Faraday efficiency of the target product. Fastening devices (tension bolts + disc springs + insulating bushings) achieve overall compression and stress buffering, ensuring the sealing and electrical connection stability between layers and preventing leakage or poor contact due to thermal expansion or stress relaxation. A pressure-holding test design (0.5MPa / 24h) verifies the airtightness of the electrolyzer, ensuring no leakage under high-pressure operation and guaranteeing safety and operational reliability. A wide power adjustment range (0–100% rated power) matches the fluctuating output of renewable energy, enabling flexible matching with intermittent energy sources such as photovoltaics and wind power, improving energy utilization and system compatibility. The modular integrated design supports multi-level power expansion; by increasing or decreasing the number of electrolysis chambers, it can be flexibly expanded to tens to hundreds of kilowatts to meet the needs of different industrial scales. Adjustable operating temperature (room temperature–80℃) adapts to the operating requirements of different catalysts and membranes, improving the adaptability of the device to different reaction systems and enhancing its adaptability to industrial scenarios. The adjustable pressure (0–0.5 MPa) regulates CO2 solubility and reaction rate, increases CO2 concentration at the cathode interface, promotes reaction kinetics, and improves conversion efficiency.

[0063] The basic principles of this application have been described above with reference to specific embodiments. However, it should be noted that the advantages, benefits, and effects mentioned in this application are merely examples and not limitations, and should not be considered as essential features of each embodiment of this application. Furthermore, the specific details disclosed above are for illustrative and facilitative purposes only, and are not limitations. These details do not limit the application to the necessity of employing the aforementioned specific details for implementation.

[0064] The above description has been given for purposes of illustration and description. Furthermore, this description is not intended to limit the embodiments of this application to the forms disclosed herein. Although numerous exemplary aspects and embodiments have been discussed above, those skilled in the art will recognize certain variations, modifications, alterations, additions, and sub-combinations thereof.

Claims

1. A MEA electrolyzer apparatus for electrocatalytic carbon dioxide reduction, characterized in that, It includes, The left negative plate (9) and the right negative plate (14) are respectively connected to the cathode of the DC power supply; The intermediate anode plate (12) is located in the center of the device and connected to the DC power supply anode; Multiple electrolytic cells are symmetrically arranged on both sides of the central anode plate along the axial direction. The multiple electrolytic cells are divided into two groups, left and right. The electrolytic cells in each group are connected in series in the circuit to form a left integrated electrolytic cell and a right integrated electrolytic cell. The left integrated electrolytic cell and the right integrated electrolytic cell are electrically isolated by the central anode plate (12) and connected in parallel in the external circuit to form a series-parallel cooperative circuit structure. The electrolytic cell includes an anode-cathode composite plate, a composite plate insulating gasket (10-1), and a cathode gas diffusion layer (10-2). The anode and cathode composite plate (10-5) has a cathode surface (17-1) on one side and an anode surface (17-2) on the other side, which respectively accommodate the cathode and anode components. The anode and cathode composite plate is provided with diagonally opposite aperture channels, wherein the hole on the lower side of the cathode surface is a CO2 inlet channel (c), and the hole on the upper side of the cathode surface is an outlet channel for the mixture of cathode products and unreacted CO2 (a); the hole on the lower side of the anode surface is an electrolyte inlet channel (d), and the hole on the upper side of the anode surface is an outlet channel for the mixture of O2 and electrolyte (b).

2. The MEA electrolyzer apparatus for electrocatalytic carbon dioxide reduction as described in claim 1, characterized in that, Preferred options also include, The left end pressure plate (7) and the right end pressure plate (16) are arranged at intervals relative to each other to serve as structural support and sealing end caps; The left end pressure plate insulating sealing gasket (8) and the right end pressure plate insulating sealing gasket (15) are respectively connected to the left end pressure plate (7) and the right end pressure plate (16) to provide electrical insulation and gas-liquid sealing between the end plate and the metal electrode plate.

3. The MEA electrolyzer apparatus for electrocatalytic carbon dioxide reduction as described in claim 1, characterized in that, It also includes a pair of fastening devices for overall compression and stress buffering, which are respectively located on the outside of the left negative plate (9) and the right negative plate (14). The fastening devices include a tension bolt (1), a nut (2), a disc spring seat (3), a disc spring (4), a disc spring guide sleeve (5), and an insulating guide sleeve (6). The insulating guide sleeve (6) is fitted onto the tension bolt (1). The disc spring guide sleeve (5), the disc spring (4), the disc spring seat (3), and the nut (2) are sequentially assembled on the outside of the tension bolt (1) on the left negative plate (9) or the right negative plate (14).

4. The MEA electrolyzer apparatus for electrocatalytic carbon dioxide reduction as described in claim 1, characterized in that, The anode-cathode composite plate includes a cathode-cathode composite plate A (11) on the left and a cathode-cathode composite plate B (13) on the right, which are axially symmetrical with respect to the middle anode plate (12).

5. The MEA electrolyzer apparatus for electrocatalytic carbon dioxide reduction as described in claim 1, characterized in that, The membrane electrode is integrated with a zero-gap structure consisting of a cathode electrode (10-3), a cathode catalyst layer, and an ion exchange membrane (10-4). The carbon black layer of the cathode electrode (10-3) is directly and physically bonded to the ion exchange membrane (10-4), and the cathode catalyst layer is loaded on the surface of the carbon black layer or the ion exchange membrane.

6. The MEA electrolyzer apparatus for electrocatalytic carbon dioxide reduction as described in claim 1, characterized in that, The cathode catalytic layer uses a nickel-based catalyst or a silver-based catalyst. The cathode catalytic layer is composited onto the carbon black layer of the cathode carbon paper electrode or onto one side of the ion exchange membrane by means of loading such as spraying.

7. The MEA electrolyzer apparatus for electrocatalytic carbon dioxide reduction as described in claim 1, characterized in that, The cathode electrode (10-3) is a carbon paper electrode, with one side of the carbon paper composited with the cathode gas diffusion layer (10-2) and the other side being a carbon black layer composite ion exchange membrane.

8. The MEA electrolyzer apparatus for electrocatalytic carbon dioxide reduction as described in claim 1, characterized in that, The cathode gas diffusion layer (10-2) is a composite laminated structure of nickel foam, nickel mesh, and nickel felt, with a porosity of >90%.

9. The MEA electrolyzer apparatus for electrocatalytic carbon dioxide reduction as described in claim 1, characterized in that, In the cathode chamber of the electrolysis chamber, an electrocatalytic CO2 reduction reaction occurs to generate CO, and in the anode chamber of the electrolysis chamber, an oxidation reaction occurs to generate O2.

10. The electrocatalytic carbon dioxide reduction method of the MEA electrolyzer apparatus for electrocatalytic carbon dioxide reduction as described in any one of claims 1-9.

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