A carbon dioxide electrolysis device

Abstract

The application discloses a carbon dioxide electrolysis device, which comprises a containing assembly and an electrolysis assembly. The containing assembly comprises a containing body which is configured with a circular containing cavity. The containing cavity contains a liquid metal electrode and an electrolyte from bottom to top in sequence. An interface between the liquid metal electrode and the electrolyte is a cathode reaction interface. One end of a current collector rod away from a direct current power source is located in the liquid metal electrode, and one end of an anode away from the direct current power source is located in the electrolyte. A blowing pipeline is used for blowing in carbon dioxide. The containing body is configured with a mounting hole. The blowing pipeline is arranged in the containing cavity. An air inlet end of the blowing pipeline is communicated with the mounting hole. An axis of an air outlet end of the blowing pipeline and the cathode reaction interface are located on the same horizontal plane. The air outlet end of the blowing pipeline and a tangential direction of the containing cavity are in the same direction, so that a low-pressure vortex core area is formed in the containing body, and the anode is arranged in the low-pressure vortex core area. According to the technical scheme, carbon gas agglomerates can be prevented from gathering in an area where the anode is located.

Description

Technical Field

[0001] This application relates to the field of electrochemical electrolysis technology, and in particular to a carbon dioxide electrolysis device. Background Technology

[0002] Carbon dioxide electrolysis devices rely on the principle of electrochemical reduction to produce elemental carbon or various carbon-containing chemicals from carbon dioxide. In existing carbon dioxide electrolysis devices, the solid carbon products generated during electrolysis easily adsorb microbubbles, forming carbon agglomerates with an apparent density lower than that of molten salt electrolytes. These low-density carbon products spontaneously float upwards and readily migrate to and contact the anode at the center of the reactor. This not only causes a reverse oxidation reaction between the carbon and the high-temperature oxygen released from the anode, resulting in product loss, but also poses a safety risk of physical short circuits. Summary of the Invention

[0003] This application proposes a carbon dioxide electrolysis device to avoid the accumulation of carbon agglomerates in the region where the anode is located.

[0004] To achieve the above objectives, this application discloses the following technical solutions:

[0005] A carbon dioxide electrolysis device, the carbon dioxide electrolysis device comprising: a containment component and an electrolysis component;

[0006] The containment assembly includes: a containment body having a circular containment cavity; the containment cavity contains a liquid metal electrode and an electrolyte in sequence from bottom to top, and the interface between the liquid metal electrode and the electrolyte is a cathode reaction interface;

[0007] The electrolysis assembly includes: an air blowing pipe and a current collector, a DC power supply, and an anode connected in sequence; the end of the current collector away from the DC power supply is located inside the liquid metal electrode, and the end of the anode away from the DC power supply is located inside the electrolyte; the air blowing pipe is used to blow in carbon dioxide;

[0008] The container is constructed with mounting holes, the air blowing pipe is disposed in the container cavity, and the air inlet end of the air blowing pipe is connected to the mounting hole. The axis of the air outlet end of the air blowing pipe and the cathode reaction interface are located on the same horizontal plane, and the air outlet end of the air blowing pipe and the tangential direction of the container cavity are in the same direction, so as to form a low-pressure vortex core region in the container. The anode is disposed in the low-pressure vortex core region.

[0009] In some technical solutions, the axis of the anode and the axis of the container coincide;

[0010] The outlet of the air blowing pipe has an eccentric distance e relative to the axis of the receiving cavity, and the eccentric distance e and the inner radius R of the receiving cavity satisfy: 0.7≤e / R≤0.95; so that the low-pressure vortex core region and the axial region of the receiving body are offset.

[0011] In some technical solutions, the cross-sectional area of ​​the air outlet end of the air blowing pipe gradually decreases or decreases in a stepwise manner along the air outlet direction.

[0012] In some technical solutions, the air outlet end of the air blowing pipe is constructed with a circular air outlet section, a gradually narrowing transition section and a rectangular air outlet section connected sequentially along the air outlet direction; wherein, the flow cross section of the circular air outlet section is smaller than the flow cross section of the gradually narrowing transition section, and the flow cross section of the gradually narrowing transition section is smaller than the flow cross section of the rectangular air outlet section.

[0013] In some technical solutions, the air inlet end of the air blowing pipe extends radially along the container.

[0014] In some technical solutions, there are multiple mounting holes and multiple air blowing pipes. The air inlet end of the corresponding air blowing pipe is connected to the corresponding mounting hole, and the air outlet ends of the multiple air blowing pipes are arranged circumferentially and symmetrically.

[0015] In some technical solutions, a flow guiding structure is provided on the inner peripheral wall of the receiving cavity. The flow guiding structure extends upward from the cathode reaction interface and is used to provide a flow channel for the gas-solid mixed phase.

[0016] In some technical solutions, the flow guiding structure is a spiral flow guiding groove formed by a partial inward concavity of the inner wall surface of the receiving cavity;

[0017] The spiral helix angle of the spiral guide groove is between 30 degrees and 60 degrees.

[0018] In some technical solutions, the container includes: a container body and a cavity cover;

[0019] The receiving body is configured with a receiving cavity open on one side, and the cavity cover is used to seal the opening of the receiving body; the receiving body is configured with the receiving cavity;

[0020] The electrolysis assembly further includes a gas outlet pipe, the gas inlet of which passes through the cavity cover and is disposed within the receiving cavity, and the gas outlet pipe is used to discharge gas from the receiving cavity.

[0021] In some technical solutions, the air inlet end of the air outlet pipe is arranged close to the inner wall of the receiving cavity and is constructed as a flared opening.

[0022] As can be seen from the above technical solution, this carbon dioxide electrolysis device utilizes a gas blowing pipe to tangentially inject carbon dioxide, forming a high-speed rotating gas film along the inner wall of the containment chamber. This gas film, through viscosity, drives the near-wall molten salt to move at high speed, exerting a radially outward drag force on the carbon agglomerates. This outward drag force counteracts the pressure difference force that propels the carbon agglomerates towards the center, confining them to the edge region of the cylinder and preventing carbon accumulation within the low-pressure vortex core region. Simultaneously, the tangentially injected gas forms a spirally rising continuous bubble phase along the outer periphery of the reactor wall. During the high-speed buoyancy propulsion of the bubble group, the gas-liquid interface exerts a significant axial fluid drag force on the adjacent carbon agglomerates through viscous friction, thereby achieving axial directional migration. In summary, this technical solution avoids a strong reverse reaction between carbon and the high-temperature oxygen evolved from the anode, and also avoids the risk of a "physical short circuit." Attached Figure Description

[0023] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are merely some examples or embodiments of this application. For those skilled in the art, other drawings can be obtained based on the provided drawings without creative effort, and this application can be applied to other similar scenarios based on the provided drawings, all of which fall within the scope of protection of this solution. Unless obvious from the linguistic context or otherwise specified, the same reference numerals in the drawings represent the same structure or operation.

[0024] Figure 1 This is a schematic diagram of one embodiment of the carbon dioxide electrolysis apparatus provided in this application.

[0025] Figure 2 A schematic diagram showing the relative positions of the low-pressure vortex core region and the anode;

[0026] Figure 3 This is a three-dimensional schematic diagram of the air blowing pipe;

[0027] Figure 4 This is a side view of the air blowing pipe;

[0028] Figure 5 This is a schematic diagram of the rectangular air outlet section of the air blowing pipe;

[0029] Figure 6 This is a schematic diagram of the structure of the container and the spiral guide channel.

[0030] in:

[0031] 10 is the receiving component, 11 is the receiving body, and 12 is the spiral guide channel;

[0032] 20 is the electrolysis assembly, 21 is the current collector, 22 is the DC power supply, 23 is the anode, 24 is the air blowing pipe, 241 is the circular air outlet section, 242 is the gradually narrowing transition section, 243 is the rectangular air outlet section; 25 is the air outlet pipe.

[0033] 30 is the liquid metal electrode, 40 is the electrolyte, and 50 is the low-pressure vortex core region. Detailed Implementation

[0034] The present application will now be described in further detail with reference to the accompanying drawings and embodiments. It is to be understood that the specific embodiments described herein are merely illustrative of the application and not intended to limit it. The described embodiments are only a part of the embodiments of the present application, and not all of them. All other embodiments obtained by those skilled in the art based on the embodiments of the present application without inventive effort are within the scope of protection of the present application.

[0035] like Figure 1 As shown, this application provides a carbon dioxide electrolysis device that can be used for the electrochemical reduction reaction of carbon dioxide, and is particularly suitable for carbon dioxide electrolysis systems using liquid metal as the cathode and electrolyte as the reaction medium. During electrolysis, carbon dioxide can participate in the reduction reaction near the cathode reaction interface and generate carbon agglomerates. Since solid carbon products easily adsorb microbubbles and form carbon agglomerates, and the apparent density of these carbon agglomerates is usually lower than that of the electrolyte, they easily float upwards and migrate to the vicinity of the anode 23, causing the products to be absorbed by oxygen generated near the anode 23, and even triggering a physical short circuit. To address this, this application uses an air blowing pipe 24 to form a swirling flow field and a low-pressure vortex core region 50 within the containment 11 to control the movement path of the solid carbon products or carbon agglomerates.

[0036] like Figure 1 and Figure 2 As shown, the carbon dioxide electrolysis device may include a housing component 10 and an electrolysis component 20.

[0037] The container assembly 10 may include a container body 11, which has a circular cavity. The cavity contains a liquid metal electrode 30 and an electrolyte 40 sequentially from bottom to top, with the interface between the liquid metal electrode 30 and the electrolyte 40 serving as the cathode reaction interface. It is understood that the liquid metal electrode 30 is located at the bottom of the cavity, and the electrolyte 40 is located above it, forming a layered structure in the vertical direction. The container body 11 may be made of a high-temperature resistant and corrosion-resistant material to withstand the high-temperature environment during carbon dioxide electrolysis and the corrosive effects of the liquid metal electrode 30 and electrolyte 40 on the container material.

[0038] like Figure 1As shown, the electrolysis assembly 20 may include: an air blowing pipe 24 and a current collector 21, a DC power supply 22, and an anode 23 connected in sequence; the end of the current collector 21 away from the DC power supply 22 is located inside the liquid metal electrode 30, and the end of the anode 23 away from the DC power supply 22 is located inside the electrolyte 40; the air blowing pipe 24 is used to blow in carbon dioxide; thus, the liquid metal electrode 30 can participate in the electrolysis reaction as a cathode, the anode 23 can participate in the electrolysis reaction as an anode, and the DC power supply 22 is used to provide the electrical energy required for electrolysis to the carbon dioxide electrolysis device.

[0039] During use, the negative terminal of the DC power supply 22 can be electrically connected to the liquid metal electrode 30 via the current collector 21, and the positive terminal of the DC power supply 22 can be electrically connected to the anode 23. During electrolysis, carbon dioxide is introduced into the containment chamber through the gas blowing pipe 24 and participates in the reaction near the cathode reaction interface between the liquid metal electrode 30 and the electrolyte 40.

[0040] like Figure 1 As shown, the container 11 has a mounting hole, and a gas blowing pipe 24 is disposed within the container cavity. The inlet end of the gas blowing pipe 24 is connected to the mounting hole. The axis of the outlet end of the gas blowing pipe 24 and the cathode reaction interface are located on the same horizontal plane, and the outlet end of the gas blowing pipe 24 is tangentially aligned with the container cavity. Therefore, carbon dioxide gas is not blown directly towards the center of the container cavity radially, but rather enters the interface region between the electrolyte 40 and the liquid metal electrode 30 tangentially. This forms a low-pressure vortex core region 50 within the container 11, and the anode 23 is disposed within the low-pressure vortex core region 50.

[0041] In the above technical solution, the tangential blowing method of the blowing pipe 24 can form a swirling flow field within the container 11. Specifically, after the carbon dioxide gas is ejected from the outlet end of the blowing pipe 24, it moves along the inner circumference of the container cavity, and drives the electrolyte 40 and the gas-liquid-solid mixed phase near the cathode reaction interface to generate a rotating flow.

[0042] It should be noted that under normal electrolysis conditions, the solid carbon generated by the reaction readily adsorbs tiny bubbles, forming carbon agglomerates with an apparent density lower than that of the molten electrolyte. When a high-speed swirling flow field is formed inside the device, the denser molten salt medium is thrown towards the inner wall of the containment cavity by centrifugal force, forming a radially decreasing pressure gradient from the outside to the inside. The resulting centripetal pressure difference drives the lightweight carbon agglomerates to accumulate in the low-pressure vortex core region 50 where the anode 23 is located. Figure 2As shown, this scheme utilizes the air-blowing pipe 24 to tangentially inject carbon dioxide, forming a high-speed rotating gas film along the inner wall of the containment cavity. This gas film, through viscosity, drives the near-wall molten salt to move at high speed, exerting a radially outward drag force on the carbon agglomerates. This outward drag force counteracts the pressure difference force that propels the carbon agglomerates towards the center, confining them to the edge region of the cylinder and preventing carbon accumulation within the low-pressure vortex core region 50. Simultaneously, the tangentially injected gas forms a spirally rising continuous bubble phase along the outer periphery of the reactor wall. During the high-speed buoyancy propulsion of the bubble group, the gas-liquid interface exerts a significant axial fluid drag force on the adjacent carbon agglomerates through viscous friction, thereby achieving axial directional migration. In summary, this technical solution avoids a strong reverse reaction between carbon and the high-temperature oxygen evolved from the anode, and also avoids the risk of a "physical short circuit."

[0043] It should also be noted that in this application, after carbon dioxide is blown in tangentially through the blowing pipe 24, a flow field with tangential velocity is formed near the cathode reaction interface. This flow field can perform in-situ stripping of the newly generated solid products, making it difficult for the solid products to be deposited on the cathode reaction interface for a long time, thereby reducing the possibility that the surface of the liquid metal electrode 30 will be covered or passivated by the products (i.e., to avoid cathode passivation).

[0044] Based on the above technical solutions, such as Figure 1 and Figure 2 As shown, the axis of the anode 23 coincides with the axis of the container 11.

[0045] The outlet of the air blowing pipe 24 has an eccentric distance e relative to the axis of the receiving cavity. The eccentric distance e and the inner radius R of the receiving cavity satisfy: 0.7≤e / R≤0.95; so that the axial regions of the low-pressure vortex core region 50 and the receiving body 11 are offset.

[0046] In the above technical solution, by limiting the ratio between the eccentric distance e and the inner radius R of the containment cavity, the carbon dioxide gas ejected from the blowing pipe 24 can form a strong tangential momentum within the containment cavity. When e / R is too small, the outlet direction of the blowing pipe 24 is closer to the center of the containment cavity, and the airflow is prone to directly impacting the area near the anode 23, which is not conducive to the isolation between the carbon agglomerates and the anode 23. When e / R is too large, the airflow is too close to the inner wall of the containment body 11, and the kinetic energy is easily attenuated rapidly due to wall friction, making it difficult to form a stable and effective swirling field within the containment cavity. Therefore, limiting e / R between 0.7 and 0.95 can balance the swirling intensity and the stability of the flow field.

[0047] Figure 3 , Figure 4 as well as Figure 5As shown, the cross-sectional area of ​​the outlet end of the blowing pipe 24 gradually decreases or decreases in a stepwise manner along the outlet direction. With this structure, the gas in the blowing pipe 24 can be accelerated and ejected when it approaches the outlet end, thereby increasing the jet velocity at the outlet end and enhancing the tangential momentum of the carbon dioxide gas after entering the containment cavity.

[0048] Based on the above technical solutions, such as Figure 3 As shown, the outlet end of the air blowing pipe 24 is constructed sequentially with a circular outlet section 241, a tapering transition section 242, and a rectangular outlet section 243 along the outlet direction. The flow cross-section of the circular outlet section 241 is smaller than that of the tapering transition section 242, and the flow cross-section of the tapering transition section 242 is smaller than that of the rectangular outlet section 243. In this technical solution, the circular outlet section 241 facilitates connection to the main pipeline of the air blowing pipe 24, the tapering transition section 242 achieves a smooth transition of the gas flow cross-section, and the rectangular outlet section 243 forms a flat jet. Through the coordination of the circular outlet section 241, the tapering transition section 242, and the rectangular outlet section 243, the local resistance generated at the cross-sectional change point can be reduced, while simultaneously enabling the gas to form a higher velocity and stronger directional tangential jet at the rectangular outlet section 243.

[0049] Based on the above technical solution, the rectangular gas outlet section 243 can be constructed as a flat slit-like structure. This flat slit-like structure allows the gas flow to form a wider coverage area near the cathode reaction interface, thereby more fully acting on the interface region between the liquid metal electrode 30 and the electrolyte 40. Preferably, the aspect ratio of the rectangular gas outlet section 243 can be greater than 2:1, or approximately 2:1, to increase the horizontal coverage area of ​​the jet and make it easier to establish a swirling flow field within the containment cavity.

[0050] In one specific technical solution, the air inlet of the air blowing pipe 24 extends radially along the container 11. With this configuration, the air blowing pipe 24 can introduce carbon dioxide gas from the side wall of the container 11, and within the container 11, a bending structure guides the gas tangentially towards the outlet direction. Specifically, the air blowing pipe 24 can be constructed as an approximately L-shaped structure, with its inlet communicating with a mounting hole on the side wall of the container 11, and its outlet arranged tangentially along the container cavity.

[0051] In a specific technical solution, there are multiple mounting holes and multiple air blowing pipes 24. The air inlet end of the corresponding air blowing pipe 24 is connected to the corresponding mounting hole, and the air outlet ends of the multiple air blowing pipes 24 are arranged circumferentially and symmetrically. Through the symmetrical arrangement of multiple air blowing pipes 24, a more uniform and stable swirling field can be formed in the accommodating cavity, reducing the local flow deviation or fluid dead zone caused by a single air blowing pipe 24.

[0052] Of course, the number of air blowing pipes 24 can be two, three, or four. When there are four air blowing pipes 24, the four air blowing pipes 24 can be evenly distributed along the circumference of the container 11, and the air outlet of each air blowing pipe 24 can tangentially emit air in the same direction of rotation. In this way, the carbon dioxide gas ejected from multiple air blowing pipes 24 can jointly drive the electrolyte 40 and the gas-liquid-solid mixture to rotate in the same direction, thereby forming a forced swirling flow field and improving the directional migration effect of carbon agglomerates.

[0053] Based on the inventive concept of this technical solution, the outlet end of the air blowing pipe 24 can also have a small elevation angle relative to the horizontal plane. For example, the outlet end of the air blowing pipe 24 can have an elevation angle of 5° to 15° relative to the bottom horizontal plane of the container 11. With this arrangement, the gas ejected from the air blowing pipe 24 has both a tangential velocity component and an upward velocity component, thereby making it easier to form a spiral upward flow field within the container cavity. This spiral upward flow field can exert an upward drag force on the solid carbon products or carbon agglomerates, causing them to migrate directionally along the circumference and axial direction of the container 11.

[0054] like Figure 6 As shown, in this embodiment, a flow-guiding structure is provided on the inner peripheral wall of the containment cavity. The flow-guiding structure extends upward from the cathode reaction interface and provides a flow channel for the gas-solid mixture. By providing the flow-guiding structure, the movement paths of bubbles and carbon agglomerates can be further constrained, causing them to migrate upwards near the inner peripheral wall of the containment body 11, thereby reducing the likelihood of them moving towards the central region of the containment cavity. This gas-solid mixture can be a mixture of carbon agglomerates and solid carbon products.

[0055] Based on the above technical solution, starting from the inventive concept, such as Figure 6 The flow guiding structure shown is a spiral flow guiding groove 12 formed by a partial indentation of the inner wall of the receiving cavity. In this technical solution, after carbon dioxide is tangentially blown into the blowing pipe 24, the bubbles and carbon agglomerates move close to the inner peripheral wall of the receiving body 11 under the action of the swirling flow field and can enter the spiral flow guiding groove 12. The spiral flow guiding groove 12 provides a physical guiding path for the gas-solid mixture to rise spirally, causing the carbon agglomerates to migrate along the outer peripheral region of the receiving body 11, thereby maintaining a distance from the anode 23 located in the central region.

[0056] The helix angle of the spiral guide channel 12 is between 30 and 60 degrees. When the helix angle is too small, the gas-solid mixture rises at a low axial speed, and carbon agglomerates tend to accumulate in the low-pressure vortex core region 50 of the containment cavity. When the helix angle is too large, the circumferential limiting and tangential guiding effects provided by the spiral guide channel 12 are weakened, which is not conducive to the stable migration of the gas-solid mixture along the inner wall region of the containment body 11. Therefore, setting the helix angle of the spiral guide channel 12 between 30 and 60 degrees can balance the axial transport efficiency and circumferential flow stability of the gas-solid mixture.

[0057] Additionally, it should be noted that the flow guiding structure can also be a spiral flow guiding rib disposed on the inner wall of the receiving cavity. The spiral flow guiding rib can be formed by protruding inward from the inner wall of the receiving cavity and extending spirally along the axial direction of the receiving body 11. Similar to the spiral flow guiding groove 12, the spiral flow guiding rib can also provide a spiral upward path for the gas-solid mixture. It can be understood that, without affecting the continuity of the main swirling flow field within the receiving cavity, both the spiral flow guiding groove 12 and the spiral flow guiding rib can be used as specific implementations of the flow guiding structure.

[0058] In a technical solution, such as Figure 1 As shown, the container 11 may include a container body and a cavity cover.

[0059] The container body has a container cavity with an opening on one side, and a cavity cover is used to seal the opening of the container body; the container body has a container cavity; wherein, by sealing the container body with the cavity cover, the possibility of external air entering the container cavity can be reduced, and the escape of gas from non-preset locations during electrolysis can be reduced.

[0060] like Figure 1 As shown, the electrolysis assembly 20 may further include: a gas outlet pipe 25, the gas inlet end of which passes through the cavity cover and is disposed in the receiving cavity, and the gas outlet pipe 25 is used to discharge the gas in the receiving cavity. During the electrolysis process, the carbon dioxide gas introduced by the gas blowing pipe 24 and the gas generated near the anode 23 can be discharged from the receiving cavity through the gas outlet pipe 25, thereby facilitating the collection, treatment or recycling of the discharged gas.

[0061] In some implementations, such as Figure 1 As shown, the inlet end of the exhaust pipe 25 is arranged close to the inner wall of the receiving cavity and is constructed as a flared opening. By arranging the inlet end of the exhaust pipe 25 close to the inner wall of the receiving cavity, it can cooperate with the swirling flow field and the spiral guide groove 12 within the receiving cavity, making it easier for the gas rising along the inner circumferential wall of the receiving body 11 to enter the exhaust pipe 25. Constructing the inlet end of the exhaust pipe 25 as a flared opening increases the effective intake area of ​​the inlet end and reduces the gas discharge resistance.

[0062] In some embodiments, the liquid metal electrode 30 can be made of liquid metal materials such as antimony, bismuth, zinc, or their alloys. The electrolyte 40 can be a carbonate system, a mixture of chloride salts and metal oxides, or other electrolyte systems suitable for carbon dioxide electrolysis. The anode 23 can be made of iron-nickel alloy, graphite, or other conductive materials suitable for the electrolysis reaction environment. The selection of the above materials can be adjusted according to the actual electrolysis temperature, target product, and device scale.

[0063] In some embodiments, a corrosion-resistant insulating sleeve may be provided on the outside of the current collector 21 to reduce direct contact between the current collector 21 and the electrolyte 40, thereby reducing the corrosive effect of the high-temperature electrolysis environment on the current collector 21. This insulating sleeve may be made of alumina ceramic or other high-temperature resistant insulating materials.

[0064] In some embodiments, the cavity cover may be provided with a through hole for the anode 23, the current collector 21, and the outlet pipe 25 to pass through, and a sealing structure may be provided at the through hole. This sealing structure can improve the sealing performance of the cavity, reduce the possibility of external air entering the cavity, and reduce the leakage of electrolytic gas from the cavity cover.

[0065] In some embodiments, the low-pressure vortex core region 50 is not necessarily understood as an absolutely static or fixed geometric region; it can be a low-pressure swirling influence region formed during the continuous blowing process of the blowing pipe 24. By adjusting the outlet position, outlet velocity, and outlet direction of the blowing pipe 24, the low-pressure vortex core region 50 can maintain a preset positional relationship relative to the anode 23, thereby reducing the risk of carbon agglomerates migrating to and contacting the anode 23.

[0066] In a specific implementation plan:

[0067] First, a liquid metal electrode 30 is added to the bottom of the container 11, and then an electrolyte 40 is added above the liquid metal electrode 30, forming a cathode reaction interface between the liquid metal electrode 30 and the electrolyte 40. Next, a current collector 21 is inserted into the liquid metal electrode 30, and an anode 23 is inserted into the electrolyte 40, establishing an electrical connection between the current collector 21, the DC power supply 22, and the anode 23. Then, carbon dioxide is introduced into the container through the air blowing pipe 24, and the DC power supply 22 is activated to initiate the electrolysis reaction.

[0068] During electrolysis, carbon dioxide gas is tangentially injected into the vicinity of the cathode reaction interface through the outlet of the gas blowing pipe 24. On the one hand, the high-speed tangential gas flow enhances the mass transfer efficiency of carbon dioxide near the cathode reaction interface; on the other hand, the high-speed tangential gas flow drives the electrolyte 40 and bubbles to form a swirling flow field, causing the generated carbon agglomerates to be subjected to fluid shearing and swirling guidance. As a result, the carbon agglomerates can be promptly stripped from the vicinity of the cathode reaction interface and migrate towards the vicinity of the inner peripheral wall of the container 11.

[0069] When the containment cavity is equipped with a spiral guide groove 12, bubbles and carbon agglomerates can enter the spiral guide groove 12 under the action of the swirling flow field and move upward along the spiral guide groove 12. In this way, the movement path of the carbon agglomerates is restricted to the outer peripheral region away from the anode 23 (i.e., away from the low-pressure vortex core region 50), thereby reducing the probability of carbon agglomerates contacting the anode 23 and reducing product loss and the risk of physical short circuit.

[0070] In summary, this application, by setting the outlet end of the gas blowing pipe 24 to be tangentially aligned with the receiving cavity and ensuring that the axis of the outlet end of the gas blowing pipe 24 and the cathode reaction interface are on the same horizontal plane, can form a tangential swirling flow field and a low-pressure vortex core region 50 near the cathode reaction interface. This swirling flow field can shear off, directionally migrate, and physically isolate solid carbon products or carbon agglomerates, reducing the risk of carbon agglomerates contacting the anode 23, thereby reducing the risk of reverse oxidation reaction and physical short circuit, and improving the operational stability of the carbon dioxide electrolysis device.

[0071] In the above context, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature.

[0072] In the description of the embodiments of this application, unless otherwise stated, " / " means "or". For example, A / B can mean A or B. "And / or" in this article is merely a description of the relationship between related objects, indicating that there can be three relationships. For example, A and / or B can mean: A exists alone, A and B exist simultaneously, and B exists alone.

[0073] It should be noted that, for ease of description, only the parts relevant to the application are shown in the accompanying drawings. Unless otherwise specified, the embodiments and features described in this application can be combined with each other.

[0074] The above description is merely a preferred embodiment of this application and an explanation of the technical principles employed, and is not intended to limit this application. Various modifications and variations can be made to this application by those skilled in the art. The scope of this application is not limited to technical solutions formed by specific combinations of the above-described technical features, but should also cover other technical solutions formed by arbitrary combinations of the above-described technical features or their equivalents without departing from the above-described application concept. For example, technical solutions formed by substituting the above features with (but not limited to) technical features with similar functions disclosed in this application.

Claims

1. A carbon dioxide electrolysis device, characterized in that, The carbon dioxide electrolysis device includes: a housing component (10) and an electrolysis component (20); The containment assembly (10) includes: a containment body (11), which has a circular containment cavity; the containment cavity contains a liquid metal electrode (30) and an electrolyte (40) sequentially from bottom to top, and the interface between the liquid metal electrode (30) and the electrolyte (40) is a cathode reaction interface; The electrolysis assembly (20) includes: a blowing pipe (24) and a current collector (21), a DC power supply (22), and an anode (23) connected in sequence; one end of the current collector (21) away from the DC power supply (22) is located inside the liquid metal electrode (30), and one end of the anode (23) away from the DC power supply (22) is located inside the electrolyte (40); the blowing pipe (24) is used to blow in carbon dioxide; The container (11) is constructed with mounting holes, the air blowing pipe (24) is disposed in the container cavity, and the air inlet end of the air blowing pipe (24) is connected to the mounting hole. The axis of the air outlet end of the air blowing pipe (24) and the cathode reaction interface are located on the same horizontal plane, and the air outlet end of the air blowing pipe (24) and the tangential direction of the container cavity are in the same direction, so as to form a low-pressure vortex core region (50) in the container (11), and the anode (23) is disposed in the low-pressure vortex core region (50).

2. The carbon dioxide electrolysis apparatus as described in claim 1, characterized in that, The axis of the anode (23) coincides with the axis of the container (11); The outlet of the air blowing pipe (24) has an eccentric distance e relative to the axis of the receiving cavity, and the eccentric distance e and the inner radius R of the receiving cavity satisfy: 0.7≤e / R≤0.95; so that the low-pressure vortex core region (50) and the axial region of the receiving body (11) are offset.

3. The carbon dioxide electrolysis apparatus as described in claim 1, characterized in that, The cross-sectional area of ​​the air outlet of the air blowing pipe (24) gradually decreases or decreases stepwise along the air outlet direction.

4. The carbon dioxide electrolysis apparatus as described in claim 2, characterized in that, The air outlet of the air blowing pipe (24) is constructed in sequence along the air outlet direction as a circular air outlet section (241), a tapering transition section (242), and a rectangular air outlet section (243); wherein, the flow cross section of the circular air outlet section (241) is smaller than the flow cross section of the tapering transition section (242), and the flow cross section of the tapering transition section (242) is smaller than the flow cross section of the rectangular air outlet section (243).

5. The carbon dioxide electrolysis apparatus as described in claim 2, characterized in that, The air inlet of the air duct (24) extends radially along the container (11).

6. The carbon dioxide electrolysis apparatus as described in claim 2, characterized in that, The number of mounting holes is multiple, the number of air blowing pipes (24) is multiple, the air inlet end of the corresponding air blowing pipe (24) is connected to the corresponding mounting hole, and the air outlet ends of the multiple air blowing pipes (24) are arranged circumferentially and symmetrically.

7. The carbon dioxide electrolysis apparatus as described in claim 1, characterized in that, A flow guiding structure is provided on the inner peripheral wall of the accommodating cavity. The flow guiding structure extends upward from the cathode reaction interface and is used to provide a flow channel for the gas-solid mixed phase.

8. The carbon dioxide electrolysis apparatus as described in claim 7, characterized in that, The flow guiding structure is a spiral flow guiding groove (12) formed by a partial inward concavity of the inner wall surface of the receiving cavity. The spiral angle of the spiral guide groove (12) is between 30 degrees and 60 degrees.

9. The carbon dioxide electrolysis apparatus as described in claim 1, characterized in that, The container (11) includes: a container body and a cavity cover; The receiving body is configured with a receiving cavity open on one side, and the cavity cover is used to seal the opening of the receiving body; the receiving body is configured with the receiving cavity; The electrolysis assembly (20) further includes an outlet pipe (25), the inlet end of which passes through the cavity cover and is disposed in the receiving cavity, and the outlet pipe (25) is used to discharge the gas in the receiving cavity.

10. The carbon dioxide electrolysis apparatus as described in claim 9, characterized in that, The air inlet end of the air outlet pipe (25) is arranged close to the inner wall of the receiving cavity and is constructed as a flared mouth.

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