High-voltage electrodes, reaction mechanisms, and reaction equipment for carbon dioxide capture and conversion.

Abstract

This invention belongs to the field of integrated carbon dioxide capture and utilization technology, specifically disclosing a high-voltage electrode, reaction mechanism, and reaction equipment for carbon dioxide capture and conversion. The high-voltage electrode comprises multiple shape memory alloy wires, which are wound and woven within a specified range to form a fluffy three-dimensional filament structure as the high-voltage electrode. By using shape memory alloy wires wound and woven to form a fluffy three-dimensional filament structure as the high-voltage electrode, it can automatically undergo periodic expansion and contraction changes by utilizing the temperature difference between the carbon dioxide capture stage at room temperature and the plasma-driven carbon dioxide stage. This allows it to maintain a fluffy state at low temperatures in the adsorption zone to maximize the adsorption contact area between the metal frame and the target gas, and to transform from a plasma self-heating state to a dense and compact state in the conversion zone to enhance the electric field and optimize the discharge gap, thus achieving adaptive optimization of the electrode morphology for the reaction steps.

Description

Technical Field

[0001] This invention relates to the field of integrated carbon dioxide capture and utilization technology, and in particular to a high-voltage electrode, reaction mechanism, and reaction equipment for carbon dioxide capture and conversion. Background Technology

[0002] Carbon capture and storage (CCS) technology is one of the effective ways to reduce carbon dioxide emissions. However, CCS technology has problems in terms of carbon dioxide compression, transportation, injection costs, and environmental safety after geological storage. In contrast, carbon capture and utilization (CCU) technology is a more promising alternative. By converting captured carbon dioxide into high-value chemicals or fuels, it can not only reduce emissions but also improve economic benefits, thereby partially offsetting the costs of carbon capture.

[0003] However, carbon capture and utilization (CCU) technologies still involve intermediate purification, compression, and transportation steps, making the entire process relatively cumbersome. Therefore, integrated carbon capture and utilization (ICCU) technologies, which can directly convert captured carbon dioxide into chemicals in situ, are becoming increasingly popular. Integrated carbon capture and utilization technologies include thermocatalysis, electrocatalysis, photocatalysis, and plasma catalysis. Among these, dielectric barrier discharge plasma reactors are one of the key pieces of equipment for realizing ICCU technology.

[0004] Dielectric barrier discharge (DBD) plasma is a form of gas discharge in which an insulating dielectric is inserted into the discharge space. This dielectric effectively blocks the discharge channel from penetrating the electrodes, thereby forming a large number of high-energy-density micro-plasma in the space. As an efficient and stable plasma generation method, this approach is widely used in integrated carbon dioxide capture and utilization (ICCU) technology. The reaction electrode is the core component of the plasma reactor. The discharge between the high-voltage and low-voltage electrodes is the direct cause of plasma generation and reaction, and it is also the working principle of the plasma reactor. Therefore, the design of the electrode structure is crucial.

[0005] Existing high-voltage electrodes used for integrated carbon dioxide capture and utilization are typically rod-shaped. Rod-shaped high-voltage electrodes have limited discharge area and few discharge points, resulting in insufficient density of active particles (such as electrons and free radicals). At the same time, the surface adsorption capacity of rod-shaped high-voltage electrodes is insufficient, making it impossible to effectively enrich the target pollutants in the discharge core area, resulting in low local pollutant concentrations, which in turn restricts the improvement of the reaction rate.

[0006] In summary, existing high-voltage electrodes used for integrated carbon dioxide capture and utilization suffer from problems such as limited discharge area, sparse discharge points, insufficient adsorption capacity of the rod-shaped high-voltage electrode surface, inability to effectively concentrate target pollutants in the discharge core area, resulting in low local pollutant concentrations. Summary of the Invention

[0007] This invention provides a high-voltage electrode for carbon dioxide capture and conversion, which can solve the problems of limited discharge area, few discharge points, insufficient adsorption capacity of the surface of rod-shaped high-voltage electrodes used for integrated carbon dioxide capture and utilization in the prior art, which cannot effectively enrich the target pollutants in the discharge core area, resulting in low local pollutant concentration.

[0008] In a first aspect, the present invention provides a high-voltage electrode for carbon dioxide capture and conversion, the high-voltage electrode comprising multiple shape memory alloy wires, the multiple shape memory alloy wires being wound and woven within a specified range to form a fluffy three-dimensional filament structure to serve as the high-voltage electrode;

[0009] The three-dimensional filament structure has a first state and a second state. When the three-dimensional filament structure is in the first state, the gap between adjacent shape memory alloy wires is larger than when the three-dimensional filament structure is in the second state.

[0010] When the actual temperature of the high-voltage electrode is higher than its phase transition temperature, the high-voltage electrode shrinks from the first state to the second state.

[0011] This invention provides a high-voltage electrode for carbon dioxide capture and conversion, which, compared to the prior art, has, but is not limited to, the following beneficial effects:

[0012] In this high-voltage electrode used for carbon dioxide capture and conversion, shape memory alloy wires possess stable phase transition characteristics, high temperature resistance, and excellent conductivity. The winding and weaving of multiple shape memory alloy wires, with the weaving density adjustable according to actual discharge requirements, ensures that the resulting three-dimensional filament structure is both fluffy and stable, preventing structural loosening and deformation due to airflow impact or electric field effects during discharge. The first state of the three-dimensional filament structure is its naturally fluffy state at room temperature, where the gaps between adjacent shape memory alloy wires are relatively large. The second state of the three-dimensional filament structure is its contracted state at high temperature. When the high-voltage electrode generates heat during discharge, and the actual temperature rises above its preset phase transition temperature, the shape memory alloy wires undergo a phase transition, causing the entire three-dimensional filament structure to contract, and the gaps between adjacent shape memory alloy wires to shrink.

[0013] This invention provides a high-voltage electrode for carbon dioxide capture and conversion. It utilizes shape memory alloy wires wound and woven to form a loose, three-dimensional filament structure as the high-voltage electrode. This structure has two forms: a first state with a larger gap and a second state with a smaller gap. The electrode can automatically transform according to its temperature. Thus, it can automatically undergo periodic expansion and contraction changes by taking advantage of the temperature difference between the carbon dioxide capture stage at room temperature and the plasma-driven carbon dioxide stage. In the adsorption region, it maintains a loose state at low temperatures to maximize the adsorption contact area between the metal frame and the target gas. In the conversion region, it transforms from a plasma-heated state to a dense, compact state to enhance the electric field and optimize the discharge gap. This achieves adaptive optimization of the electrode morphology to the reaction steps.

[0014] As a further aspect of the present invention: the shape memory alloy wire is a nickel-titanium-based shape memory alloy wire, and the phase transformation temperature of the nickel-titanium-based shape memory alloy wire is 80-120℃.

[0015] As a further aspect of the present invention: the nickel content in the nickel-titanium based shape memory alloy wire is 50.8 at.%, and the diameter of the shape memory alloy wire is 100±50μm.

[0016] As a further aspect of the present invention, the method for preparing the shape memory alloy wire includes: solution treatment of the wire at 550°C for 20 minutes in a vacuum furnace followed by water quenching, then tightly winding it around a ceramic mandrel of the target diameter, constraining annealing at 450°C for 15 minutes, and quenching.

[0017] As a further aspect of the present invention: adsorbent particles are provided in the gaps of the three-dimensional filament structure, and / or, a catalytic layer and an adsorption layer are provided on the surface of the high-voltage electrode.

[0018] In a second aspect, the present invention provides a reaction mechanism for carbon dioxide capture and conversion, the reaction mechanism comprising:

[0019] A medium tube, wherein the medium tube has a reaction chamber inside;

[0020] A high-voltage electrode is disposed inside the reaction chamber. The lead of the high-voltage electrode extends to the outside of the dielectric tube and is connected to an external power supply via a brush. The high-voltage electrode is the high-voltage electrode for carbon dioxide capture and conversion provided in the first aspect of the present invention.

[0021] A low-pressure electrode is disposed on the outer wall of the dielectric tube, and the dimension of the low-pressure electrode along the length of the dielectric tube is the same as the dimension of the high-pressure electrode along the length of the dielectric tube.

[0022] The low-voltage electrode is connected to the grounding system via a grounding wire.

[0023] As a further aspect of the present invention: the low-voltage electrode comprises, from the inside out, a bonding layer, a conductive layer and a wear-resistant protective layer.

[0024] As a further aspect of the present invention: the bonding layer is silver paste containing 20-30 wt% glass powder, the conductive layer is pure silver paste, and the wear-resistant protective layer is a silver-based composite material doped with titanium dioxide.

[0025] As a further aspect of the present invention: the inlet end of the medium tube is provided with an inlet flange, which is connected to the medium tube by a fixing nut; a power interface is provided at the end of the inlet flange away from the medium tube, and a high-voltage interface is provided at the center of the inlet flange; an electrode sleeve is provided inside the high-voltage interface, and the electrode sleeve is coaxially arranged with the medium tube; an electrode bundle is provided inside the electrode sleeve, one end of the electrode bundle is led out through the power interface for connecting to an external power source, and the other end of the electrode bundle is used to connect to a three-dimensional filament structure serving as a high-voltage electrode.

[0026] Thirdly, the present invention provides a reaction device for integrating carbon dioxide capture and utilization, the reaction device including the reaction mechanism for carbon dioxide capture and conversion provided in the embodiments of the second aspect of the present invention. Attached Figure Description

[0027] The accompanying drawings, which are included to provide a further understanding of the invention and form part of this application, illustrate exemplary embodiments of the invention and, together with their description, serve to explain the invention and do not constitute an undue limitation thereof. In the drawings:

[0028] Figure 1 This is a longitudinal cross-sectional schematic diagram of the reaction mechanism in one embodiment of the present invention;

[0029] Figure 2 This is a cross-sectional schematic diagram of the reaction mechanism in one embodiment of the present invention;

[0030] Figure 3 This is a schematic cross-sectional view of the low-voltage electrode in one embodiment of the present invention.

[0031] Figure 4 This is a schematic diagram of a reaction apparatus according to one embodiment of the present invention;

[0032] Figure 5 This is a schematic diagram of the reactor section in one embodiment of the present invention;

[0033] Figure 6 This is a statistical chart of the test results of the reaction equipment in Embodiment 1 of the present invention.

[0034] Explanation of reference numerals in the attached figures:

[0035] 1. Reactor; 2. Gas source; 3. External power supply; 4. Oscilloscope; 5. Mass spectrometer; 6. Flue gas analyzer; 7. Control terminal; 001. Stator housing; 002. Reaction mechanism; 003. Gas distribution plate; 004. First gas port; 005. Second gas port; 006. Third gas port; 007. Brush; 008. Rotating shaft; 101. Power interface; 102. High-voltage interface; 103. Inlet flange; 104. 105. Inlet port; 106. Sealing gasket; 107. Flange bushing; 108. Fixing nut; 201. Three-dimensional filament structure; 202. Dielectric tube; 203. Low-pressure electrode; 204. Electrode bundle; 205. Electrode sleeve; 206. Mica wire; 301. Outlet flange; 302. Outlet port; 303. Outlet pipe; 401. Bonding layer; 402. Conductive layer; 403. Wear-resistant protective layer. Detailed Implementation

[0036] To make the objectives, technical solutions, and advantages of this application clearer, the technical solutions in the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings showing multiple embodiments according to this application. It should be understood that the described embodiments are only a part of the embodiments of this application, and not all of the embodiments. All other embodiments obtained by those skilled in the art based on the embodiments described in this application without creative effort will fall within the scope of protection of this application.

[0037] Unless otherwise defined, all technical and scientific terms used in this application have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains; the terminology used in the specification of this application is for the purpose of describing specific embodiments only and is not intended to limit this application; the terms "comprising," "including," "having," "containing," etc., in the specification, claims, and accompanying drawings of this application are open-ended terms. Therefore, "comprising," "including," or "having" refers to, for example, a method or apparatus having one or more steps or elements, but is not limited to having only these one or more elements. The terms "first," "second," etc., in the specification, claims, or accompanying drawings of this application are used to distinguish different objects, not to describe a specific order or hierarchy. Furthermore, 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 indicated technical features. Thus, a feature defined with "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this application, unless otherwise stated, "a plurality of" means two or more.

[0038] In the description of this invention, it should be understood that the terms "upper", "lower", "left", "right", "front", "rear", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to 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.

[0039] In the description of this application, it should be noted that, unless otherwise expressly specified and limited, the terms "installation," "connection," "linking," and "attachment" 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 or an indirect connection through an intermediate medium; and they can refer to the internal communication between two components. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.

[0040] It should be emphasized that when the term "comprising / including" is used in this specification, it is used to explicitly indicate the presence of the stated feature, integer, step, or component, but does not exclude the presence or addition of one or more other features, integers, steps, parts, or groups of features, integers, steps, or parts.

[0041] In this application, the term "and / or" is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, B and / or C can represent: B existing alone, B and C existing simultaneously, or C existing alone. Additionally, in this application, the character " / " generally indicates that the preceding and following related objects have an "or" relationship.

[0042] High-voltage electrodes used in integrated carbon dioxide capture and utilization (ICCU) technologies are typically rod-shaped. These rod-shaped electrodes have limited discharge area and few discharge points, resulting in insufficient density of active particles (such as electrons and free radicals). Furthermore, their surface adsorption capacity is insufficient, failing to effectively concentrate target pollutants in the discharge core region, leading to low local pollutant concentrations and thus limiting reaction rate improvement. On the other hand, existing high-voltage electrodes cannot meet the varying electrode shape requirements of different ICCU reaction stages. For example, the adsorption stage requires maximum contact between the material and carbon dioxide (high adsorption area), while the conversion stage requires a strong electric field and high catalytic activity. However, the fixed structure of existing rod-shaped high-voltage electrodes cannot adapt to different reaction stages.

[0043] Based on this, such as Figure 1 , Figure 2As shown, this application provides a high-voltage electrode for carbon dioxide capture and conversion. The high-voltage electrode includes multiple shape memory alloy wires, which are wound and woven within a specified range to form a fluffy three-dimensional filament structure 201 to serve as the high-voltage electrode.

[0044] The three-dimensional filament structure 201 has a first state and a second state. When the three-dimensional filament structure 201 is in the first state, the gap between adjacent shape memory alloy wires is larger than the gap between adjacent shape memory alloy wires when the three-dimensional filament structure 201 is in the second state.

[0045] When the actual temperature of the high-voltage electrode is higher than its phase transition temperature, the high-voltage electrode shrinks from the first state to the second state. The specified range is adapted to the size of the reaction mechanism 002 to which it is applicable. For example, in the first state, the three-dimensional filament structure 201 formed by the high-voltage electrode occupies 80%-90% of the internal space of the quartz tube serving as the reaction chamber.

[0046] Specifically, when the high-voltage electrode in this embodiment is used in carbon dioxide capture and utilization technology, during the adsorption stage, the three-dimensional filament structure 201 serving as the high-voltage electrode is in a relatively loose first state, with larger gaps between adjacent shape memory alloy wires. At this time, the three-dimensional filament structure 201 can fully contact the introduced gas to ensure the adsorption effect of carbon dioxide. During the conversion stage, the high-voltage electrode will heat up after being energized. When the actual temperature of the high-voltage electrode reaches its phase transition temperature, the high-voltage electrode shrinks from the first state to the second state. That is, during the conversion stage, the three-dimensional filament structure 201 serving as the high-voltage electrode is in a dense and compact second state. At this time, the high-voltage electrode can provide a strong electric field and high catalytic activity to fully ensure the reaction effect.

[0047] In detail, a loose three-dimensional filament structure 201, formed by winding and weaving shape memory alloy wires, is used as a high-voltage electrode. This structure automatically undergoes periodic expansion and contraction due to the temperature difference between the carbon dioxide capture stage at room temperature and the plasma-driven carbon dioxide stage. In the adsorption zone, it maintains a loose state at low temperatures to maximize the adsorption contact area between the metal framework (the three-dimensional filament structure 201 as the high-voltage electrode) and the target gas. In the conversion zone, it transforms from a plasma-induced heat dissipation state to a dense and compact state to enhance the electric field and optimize the discharge gap. This achieves adaptive optimization of the electrode morphology to the reaction steps. This dynamic adaptive capability allows a single electrode to simultaneously meet the differentiated optimal requirements for mass transfer and energy transfer in different steps, achieving a synergistic improvement in carbon dioxide capture efficiency and plasma catalytic conversion efficiency.

[0048] The design of shape memory alloy wires can take many forms, and there are no specific restrictions on them.

[0049] In some embodiments of the present invention, the shape memory alloy wire is a nickel-titanium-based shape memory alloy wire. The phase transition temperature of the nickel-titanium-based shape memory alloy wire is 80-120℃. When the temperature of the nickel-titanium-based shape memory alloy wire is lower than the martensitic phase transition end temperature of 50℃, the electrode is in a loose state with high porosity. At this time, the specific surface area of ​​the electrode is large, which also means that the volume of the catalyst's filling framework is increased, thus increasing the contact area between the catalyst and carbon dioxide gas, which is beneficial to improving the adsorption effect. When the plasma self-heats and its temperature is higher than the phase transition temperature, the electrode shrinks into a dense state, the porosity decreases, and the overall structure is more compact, which is beneficial to providing a stronger electric field and higher catalytic activity. The nickel content in the nickel-titanium-based shape memory alloy wire is 50.8 at.%, and the diameter of the shape memory alloy wire is 100±50μm.

[0050] In some embodiments of the present invention, the method for preparing shape memory alloy wire includes: solution treating the wire at 550°C for 20 minutes in a vacuum furnace, followed by water quenching, then tightly winding it onto a ceramic mandrel of a target diameter, constraining and annealing at 450°C for 15 minutes, and then quenching to obtain the shape memory alloy wire. In this process, the "tightly wound state (second state)" is set as the "memory shape" of its high-temperature austenitic phase (A_f≈100°C), while the "loose state (first state)" at room temperature is its martensitic phase morphology.

[0051] In some embodiments of the present invention, the surface of the high-voltage electrode may be loaded with a catalytic layer (such as Cu) and an adsorption layer (such as Al2O3) to ensure the adsorption conversion effect. In addition, the high-voltage electrode may also integrate an electrostatic drive function. By setting an insulating layer and a drive electrode on the electrode surface, applying high-voltage electrostatics can cause the electrode filament to vibrate slightly, which is used to resist carbon deposition and enhance mass transfer.

[0052] like Figure 1 , Figure 2 , Figure 3 As shown in the embodiment of this application, a reaction mechanism for carbon dioxide capture and conversion is also provided. The reaction mechanism 002 includes a medium tube 202, a high-voltage electrode, and a low-voltage electrode 203, etc.

[0053] The dielectric tube 202 contains a reaction chamber. The high-voltage electrode is the high-voltage electrode for carbon dioxide capture and conversion provided in the first aspect of the present invention. The high-voltage electrode is disposed inside the reaction chamber, and its leads extend to the outside of the dielectric tube 202 and are connected to an external power supply 3 via a brush 007. The low-voltage electrode 203 is disposed on the outer wall of the dielectric tube 202. The dimension of the low-voltage electrode 203 along the length of the dielectric tube 202 is the same as the dimension of the high-voltage electrode along the length of the dielectric tube 202 in the second state. The low-voltage electrode 203 is connected to a grounding system via a grounding wire. Specifically, the low-voltage electrode 203 can be connected to an external low-voltage power supply via a mica wire 206.

[0054] In carbon dioxide capture and utilization technology, the reaction mechanism 002 described above is employed. A loose, three-dimensional filament structure 201, formed by winding and weaving shape memory alloy wires, serves as the high-voltage electrode. This structure automatically undergoes periodic expansion and contraction due to the temperature difference between the carbon dioxide capture stage at room temperature and the plasma-driven carbon dioxide stage. In the adsorption zone, it maintains a loose state at low temperatures to maximize the adsorption contact area between the metal frame (the three-dimensional filament structure 201 as the high-voltage electrode) and the target gas. In the conversion zone, it transitions from a plasma-induced heat dissipation state to a dense, compact state to enhance the electric field and optimize the discharge gap. This achieves adaptive optimization of the electrode morphology to the reaction steps. This dynamic adaptive capability allows a single electrode to simultaneously meet the differentiated optimal requirements for mass transfer and energy transfer in different steps, achieving a synergistic improvement in carbon dioxide capture efficiency and plasma catalytic conversion efficiency.

[0055] like Figure 1 , Figure 2 As shown, in some embodiments of the present invention, the dielectric tube 202 can be a quartz tube, which can be a high-temperature resistant dielectric material; for example, the quartz tube is cylindrical with an outer diameter of 8 cm and an inner diameter of 5 cm.

[0056] like Figure 1 As shown, in some embodiments of the present invention, the inlet flange 103 is fixed to the inlet end of the quartz tube by a fixing nut 108; a flange bushing 107 is installed inside the flange, and the flange bushing 107 is coaxially arranged with the quartz tube. Specifically, the flange bushing 107 is divided into two parts: one part is located inside the quartz tube and fits with the inner wall of the quartz tube, and the other part is located at the end of the quartz tube, between the inlet flange 103 and the quartz tube; a sealing gasket 106 is installed at the flange interface; the flange bushing and sealing gasket 106 ensure the airtightness between the reaction chamber inside the quartz tube and the external environment. Similarly, the outlet flange 301 is fixed to the outlet end of the quartz tube by a fixing nut 108, and a corresponding flange bushing 107 and sealing gasket 106 are provided to ensure sealing performance.

[0057] like Figure 1As shown, in some embodiments of the present invention, the air inlet 104 is located on the side of the air inlet flange 103, and the air inlet 104 can be an end face mechanical interface; the air inlet pipe 105 is located at the air inlet 104, one end of the air inlet pipe 105 is connected to the reaction chamber inside the quartz tube, and the other end of the air inlet pipe 105 is used to connect to the gas source 2; similarly, the air outlet 302 can be installed at the end of the air outlet flange 301 and is coaxially arranged with the air outlet flange 301; the air outlet pipe 303 is located at the air outlet 302, one end of the air outlet pipe 303 is directly connected to the reaction chamber inside the quartz tube, and the other end is connected to a designated location, such as a conveying pipeline or other corresponding structure, for gas conveying.

[0058] like Figure 1 , Figure 2 As shown, in some embodiments of the present invention, the high-voltage electrode is located at the inlet flange 103. Specifically, a power interface 101 is provided at the end of the inlet flange 103 away from the quartz tube, and a high-voltage interface 102 is provided at the center of the inlet flange 103. An electrode sleeve 205 is provided inside the high-voltage interface 102, and the electrode sleeve 205 is coaxially arranged with the quartz tube. An electrode bundle 204 is provided inside the electrode sleeve 205. One end of the electrode bundle 204 is led out through the power interface 101 for connecting to an external power source 3, and the other end of the electrode bundle 204 is used to connect to the three-dimensional filament structure 201, which serves as the high-voltage electrode. The electrode sleeve 205 provides support for the electrode bundle 204. Furthermore, a support nut for supporting the electrode and a sealing ring for ensuring sealing are provided at the high-voltage interface 102.

[0059] like Figure 2 As shown, in some embodiments of the present invention, the quartz tube may be filled with carbon dioxide adsorbent / catalyst particles (such as CaO / Ca(OH)2), which fill the gaps in the three-dimensional filament structure 201 serving as a high-voltage electrode, for adsorbing carbon dioxide during the adsorption stage. The carbon dioxide adsorbent and catalyst can be selected from Ca(OH)2 powder particles with a size of 60-150 mesh. By filling the quartz tube with carbon dioxide adsorbent Ca(OH)2 particles, efficient carbon dioxide capture and utilization can be achieved at room temperature and atmospheric pressure, thereby reducing production and operating costs, improving the overall efficiency and economy of the ICCU process, and facilitating large-scale, cost-effective ICCU deployment.

[0060] Furthermore, in some embodiments of the present invention, related accessories of the inlet flange 103 and the outlet flange 301, such as the flange bushing 107 and the sealing gasket 106, are all made of PTFE. The power interface 101, high-voltage interface 102, inlet interface 104, inlet pipe 105, outlet interface 302, and outlet pipe 303 can all be made of PTFE. The electrode bundle 204 can be made of copper.

[0061] In some embodiments of the present invention, such as Figure 3 As shown, the low-voltage electrode 203 can be made of silver and can be fixed to the surface of a quartz tube by calcination. The mica wire 206 is mounted on the conductive silver paste low-voltage electrode 203 by welding. Specifically, the low-voltage electrode 203 includes, from the inside out, a bonding layer 401, a conductive layer 402, and a wear-resistant protective layer 403. The bonding layer 401 is a silver paste containing 20-30 wt% glass powder; the conductive layer 402 is pure silver paste; and the wear-resistant protective layer 403 is a silver-based composite material doped with titanium dioxide.

[0062] like Figure 3 As shown, in some embodiments of the present invention, the low-voltage electrode 203 is composed of three layers of different silver pastes: the inner layer of the low-voltage electrode 203 is a high-bonding layer 401, which can be silver paste containing 30wt% low-melting-point glass powder, and the thickness can be 2mm. The glass phase in the silver paste forms a firm bond with the surface of the quartz tube, eliminating the micron-sized air gap between it and the dielectric tube 202; the middle layer is a high-conductivity layer 402, which can be pure silver paste, and the thickness can be 6mm; the outer layer is a wear-resistant protective layer 403, which can be a silver-based composite material doped with 25wt% titanium dioxide, and the thickness can be 2mm.

[0063] The aforementioned three-layer silver paste can be formed by silver plating. Specifically, firstly, conductive silver paste of the corresponding composition is evenly applied to the quartz tube. After each application of silver paste, it is dried, and then the next layer of silver paste is applied. After the three layers are applied, the temperature is raised to 550°C in a tube furnace at a heating rate of 5°C / min and fired for 2 hours. Then, the temperature is lowered to room temperature at a cooling rate of 5°C / min to sinter the multi-layer composite low-voltage electrode 203 onto the outer wall of the quartz tube.

[0064] In related technologies, the low-pressure electrode 203 is typically made of copper mesh or aluminum foil, and is simply wrapped around the outer wall of the dielectric tube 202. This mechanical contact inevitably creates a micron-sized air gap between the metal mesh and the surface of the dielectric tube 202. This air gap causes some of the electric field energy to be ineffectively dissipated, forming an "air gap capacitance," which significantly reduces the efficiency of the electric field energy acting effectively on the reactant gas in the reactor 1, resulting in energy loss. In addition, the electric field formed between the metal mesh and the surface of the dielectric tube 202 can also ionize substances such as N2 and O2 in the micron-sized atmospheric air gap, generating atmospheric pollutants such as NO, NO2, and O3, causing secondary pollution to the environment.

[0065] In this embodiment, the low-voltage electrode 203 is a silver-based coated electrode with a gradient composite structure. Through the multi-layer composite low-voltage electrode 203 design of a high-bonding bottom layer, a conductive intermediate layer and a wear-resistant protective layer 403, a firm bond with the dielectric tube 202, efficient heat dissipation and stable conductivity are achieved. The micron-sized air gap between the electrode and the dielectric tube 202 is basically eliminated, fundamentally eliminating the main source of parasitic capacitance. This allows the electric field energy to be used more effectively to activate the reactant gas, thereby directly reducing energy loss. At the same time, since the air gap discharge is eliminated, the generation of secondary pollutants during the reaction process is effectively avoided, and the durability of the low-voltage electrode 203 is improved.

[0066] like Figure 4 , Figure 5 As shown in the embodiments of this application, a reaction apparatus is also provided. This apparatus integrates carbon dioxide capture and utilization. The reaction apparatus includes: a reactor 1, a gas distribution assembly, an oscilloscope 4, a mass spectrometer 5, a flue gas analyzer 6, an external power supply, a drive mechanism, and a control terminal 7. The external power supply is connected to the high-voltage electrode of the reaction mechanism 002 for power supply. The oscilloscope 4 is connected to the external power supply and is used to display the waveforms of voltage and current in real time. The flue gas analyzer 6 and the mass spectrometer 5 are respectively connected to the reactor 1. The flue gas analyzer 6 is used to monitor the changes in gas concentration before and after the reaction in real time, thereby calculating the capture efficiency and conversion rate. The mass spectrometer 5 can scan all mass-to-charge ratios to help detect unexpected intermediate products (such as methanol, formaldehyde, and other liquid product vapors) or trace leaks. The control terminal 7 is used to control the start-up and shutdown actions of various parts of the reaction apparatus. The control terminal 7 can be a computer terminal. The gas distribution assembly is used to provide the corresponding gas to the reactor 1.

[0067] like Figure 5 As shown, in some embodiments of the present invention, reactor 1 includes a stator housing 001, which serves as the main support structure of reactor 1. The stator housing 001 contains three sets of reaction mechanisms for carbon dioxide capture and conversion as described above. Each set of reaction mechanisms 002 includes at least one media tube 202. The stator housing 001 can be a cylindrical stainless steel (316L) cavity with an inner diameter of 40cm, a height of 60cm, and a wall thickness of 1.2cm. The media tube 202 can be detachably connected to the bottom wall of the stator housing 001, and the connection point can be fitted with two fluororubber sealing rings, one above the other, pressed into a precision mounting hole at the bottom of the stator housing 001 to achieve sealing and quick assembly / disassembly.

[0068] like Figure 5As shown, in some embodiments of the present invention, the gas distribution assembly includes a gas distribution disk 003, on which multiple sets of gas ports can be arranged circumferentially for supplying gas to the corresponding reaction mechanism 002. The gas distribution disk 003 can be a hard aluminum alloy (7075) disk with a thickness of 45 mm. Specifically, the multiple sets of gas ports can be a first gas port 004, a second gas port 005, and a third gas port 006. The first gas port 004 can be connected to a gas cylinder for containing purge gas (such as argon, nitrogen, or other inert gases) through a pipeline, and the location of the first gas port 004 is the purge cooling zone. The second gas port 005 can be connected to a gas cylinder for containing reaction gas (such as hydrogen / Ar) through a pipeline, and the location of the second gas port 005 is the carbon dioxide conversion zone. Since the process of introducing reaction gas is a conversion process that requires electricity. Therefore, the brush 007 can be connected to the gas distribution plate 003 and aligned with the position of the second gas port 005; the third gas port 006 can be connected to a gas cylinder containing (carbon dioxide) pollutant gas via a pipeline, and the location of the third gas port 006 is the carbon dioxide adsorption zone; the inlet port 104 of each medium tube 202 can be connected to the gas distribution plate 003 via a connecting pipeline, and the gas distribution plate 003 and the connecting pipeline are dynamically connected and sealed to distribute and supply gas to the medium tube 202. The interface of the connecting pipeline of the medium tube 202 can be located on a circle with a radius of 15cm on the turntable. When the gas distribution plate 003 rotates to different positions, each gas port connects to the corresponding connecting pipeline, thereby supplying the corresponding gas to the corresponding medium tube 202.

[0069] A positioning and sealing structure is provided between the air inlet 104 of the medium pipe 202 (the end of the connecting pipe away from the medium pipe 202) and the corresponding gas supply interface (on the gas distribution plate 003). After the rotating shaft 008 drives the gas distribution plate 003 to rotate to a predetermined angle, its air inlet 104 is aligned with the gas supply interface of the corresponding station, and an airtight connection is formed through the sealing connection structure. After completing the corresponding reaction process (adsorption, purging and cooling, or conversion) at the station, the rotor rotates to the next position. The sealing connection structure is preferably a positioning and sealing structure, which can adopt one or more of the following: end face compression seal, elastic sealing ring seal, conical surface fit seal, or sleeve seal. Through the above structure, the complexity of continuous dynamic gas supply sealing can be avoided during the rotor rotation process, while stable gas supply and anti-cross-flow can be achieved during the station dwell phase.

[0070] like Figure 4 , Figure 5As shown, in some embodiments of the present invention, the gas distribution disk 003 may include a movable disk and a fixed disk, with the movable disk located above and the fixed disk located below. Both the movable disk and the fixed disk (not shown in the figure) are horizontally arranged and in close contact. A first gas port 004, a second gas port 005, and a third gas port 006 are respectively provided on the top surface of the movable disk. The movable disk has through holes corresponding to the positions of the first gas port 004, the second gas port 005, and the third gas port 006 for communication. The fixed disk has through holes corresponding to the first gas port 004, the second gas port 005, and the third gas port 006, and the bottom surface of the fixed disk is connected to multiple connecting pipes, the other end of which is connected to the medium pipe 202. Thus, during the rotation of the movable disk, the corresponding gases can be sequentially introduced into the corresponding medium pipes 202. Specifically, for example, initially, the first air port 004 is connected to the first medium pipe 202 through the through hole on the movable plate, the through hole on the fixed plate, and the connecting pipe; similarly, the second air port 005 is connected to the second medium pipe 202; the third air port 006 is connected to the third medium pipe 202; when needed, the movable plate is rotated by a specified angle. At this time, the first air port 004 rotates to the position of the second medium pipe 202 and is connected to the second medium pipe 202, the second air port 005 is connected to the third medium pipe 202, and the third air port 006 is connected to the first medium pipe 202.

[0071] like Figure 4 , Figure 5 As shown, in some embodiments of the present invention, a drive mechanism is used to drive the gas distribution disk 003 to rotate; the drive mechanism may include a power source and a rotating shaft 008, the power source (such as a servo motor, not shown in the figure) drives the rotating shaft 008, and the top end of the rotating shaft 008 is connected to the movable disk in the gas distribution disk 003 to drive it to rotate.

[0072] like Figure 4 , Figure 5 As shown, in some embodiments of the present invention, the control terminal 7 can be used to control the start-up and shutdown of various parts of the reaction equipment, the on / off state or opening degree of the gas supply passage of the gas source 2, etc. The control terminal 7 may include multiple sensors (such as position sensors, not shown in the figure) and a central controller (such as a mobile terminal controller, a computer terminal controller, etc.). The central controller can control the operation of various parts of the equipment based on the signals of each sensor or a preset program. For example, the central controller controls the servo motor to drive the rotating shaft 008 to rotate intermittently according to the preset program, and controls the start-up and shutdown of the solenoid valves of each gas passage, the start-up and shutdown of each power supply and the output parameters according to the position of the rotating shaft 008. Its specific working process can be set according to the actual situation, and there are no specific limitations.

[0073] The following description uses an example of a stator housing 001 containing three sets of medium tubes 202, each set including a quartz tube, to illustrate the operation of the reaction equipment. Similarly, the gas distribution plate 003 has three sets of gas ports, each set containing one port, which are defined as the first gas port 004 for supplying argon, the second gas port 005 for supplying hydrogen, and the third gas port 006 for supplying carbon dioxide. The first gas port 004, the second gas port 005, and the third gas port 006 correspond to the purging zone, the conversion zone, and the adsorption zone, respectively.

[0074] Initially, the first gas port 004, the second gas port 005, and the third gas port 006 are each connected to a medium pipe 202 (medium pipe 202-1, medium pipe 202-2, and medium pipe 202-3, respectively). During operation, after the equipment is started, the solenoid valve on the gas path containing the third gas port 006 opens, introducing carbon dioxide-containing gas into medium pipe 202-3 for carbon dioxide adsorption. After a specified time, the gas distribution disk 003 is rotated 120° via the rotating shaft 008. At this time, the third gas port 006 rotates to the position of medium pipe 202-1, and carbon dioxide-containing gas is introduced into medium pipe 202-1. Medium pipe 202-1 is now in the adsorption zone, undergoing carbon dioxide adsorption. Simultaneously, the second gas port 005 rotates to the position of medium pipe 202-3, and hydrogen gas is introduced into medium pipe 202-3. At the same time, the electric... As the moving disk of gas distribution plate 003 moves, brush 007 is moved to position three of medium tube 202, supplying power to the high-voltage electrode of medium tube 202. At this time, medium tube 202 is in the conversion zone, undergoing a carbon dioxide conversion reaction. After a specified time, the rotating shaft 008 drives the moving disk to rotate 120° again. At this time, the third gas port 006 moves to position two of medium tube 202, which is in the adsorption zone, undergoing a carbon dioxide adsorption process. Simultaneously, the second gas port 005 moves to position one of medium tube 202, connecting with medium tube 202, which is in the conversion zone, undergoing a carbon dioxide conversion reaction. The first gas port 004 rotates to position three of medium tube 202, introducing argon gas into medium tube 202 after the conversion reaction is completed for purging and cooling, removing any residual hydrogen gas from the reaction stage to avoid affecting the adsorption effect of the next cycle.

[0075] In subsequent cycles, when the dielectric tube 202 rotates to the adsorption zone corresponding to the third gas port 006, gas containing carbon dioxide is introduced into the corresponding dielectric tube 202 through the third gas port 006 to carry out the adsorption process. At this time, the high-voltage electrode is in a fluffy state (first state), and the adsorbent and carbon dioxide adsorption area is at its maximum. When the dielectric tube 202 rotates to the conversion zone corresponding to the second gas port 005, hydrogen is introduced into the corresponding dielectric tube 202 as a reaction gas through the second gas port 005. At the same time, the brush 007 is connected to the high-voltage electrode of the corresponding dielectric tube 202 to supply power for plasma discharge to carry out the carbon dioxide conversion process. During this process, the plasma self-heats and heats the shape memory alloy wire, causing the three-dimensional filament structure 201 formed by the shape memory alloy wire as the high-voltage electrode to shrink into a dense state (second state). When the dielectric tube 202 rotates to the purging zone corresponding to the first gas port 004, argon gas is introduced into the corresponding dielectric tube 202 through the first gas port 004 for purging and cooling. This removes the residual hydrogen gas from the reaction stage to avoid affecting the adsorption effect of the next cycle. At the same time, it restores the three-dimensional filament structure 201 formed by the shape memory alloy wire as the high-voltage electrode to its fluffy first state, so as to facilitate the subsequent adsorption process. In this way, continuous automated operation of carbon dioxide capture and utilization can be realized.

[0076] It should be noted that the duration of each reaction process within a single cycle (i.e., the specified time) can be selected according to actual needs, and there are no specific restrictions on this. For example, the movable disk of the gas distribution disk 003 rotates once every 30 minutes, meaning that one reaction process (adsorption, conversion) lasts for 30 minutes. During the purging phase, argon gas can be introduced for 10 minutes, followed by natural cooling for 20 minutes.

[0077] It is worth mentioning that, in order to avoid the pipes connecting the gas inlet and the corresponding gas cylinder from twisting and getting tangled, the movable disc can perform a reset action after rotating one revolution. That is, the movable disc can rotate one revolution forward intermittently, then rotate one revolution in the opposite direction to reset, and then rotate forward again to perform alternating actions of multiple reaction processes.

[0078] In related technologies, ICCUs mostly employ fixed-bed reaction structures, requiring adsorption and conversion steps to be carried out intermittently within the same reaction zone. This sequential operation method has the following problems: residual carbon dioxide in the adsorption stage can dilute the reaction gas (such as hydrogen) in the conversion stage, reducing reaction efficiency and product selectivity; the heat generated in the conversion stage may adversely affect the adsorption of carbon dioxide by the adsorbent.

[0079] In this application, a rotary three-zone (adsorption zone, purge and cooling zone, and conversion zone) reactor 1 structure is adopted. The reaction mechanism 002 alternately enters the dedicated carbon dioxide adsorption zone, purge and cooling zone, and carbon dioxide conversion zone in space, thereby realizing a continuous cycle of carbon dioxide capture and utilization process in time. In this way, the carbon dioxide adsorption and conversion processes are separated in space and the carbon dioxide capture and utilization process is continuously cycled in time to eliminate the mutual interference between the three steps. Moreover, the independent purge zone can completely remove residual carbon dioxide and ensure a near-pure hydrogen atmosphere in the conversion zone. This greatly improves the selectivity of the hydrogenation reaction (such as high CO selectivity) and the single-pass conversion rate and selectivity.

[0080] The technical effects of this application will be described in detail below through some specific embodiments.

[0081] Example 1

[0082] Based on the above reaction equipment, ICCU experiments can be performed directly, such as... Figure 4 As shown, the main experimental setup includes a rotary reactor 1, a gas source 2, an external power supply 3, an oscilloscope 4, a mass spectrometer 5, a flue gas analyzer 6, and a computer terminal. Three media tubes 202 are used to provide the reaction space and are evenly distributed at 120° intervals along the axial direction of the stator housing 001. The high-voltage electrode is a wound wire structure electrode made of nickel-titanium shape memory alloy wire (A_f=100℃) as described above. The low-voltage electrode 203 is a gradient functional silver-based composite electrode as described above, with an inner layer containing 30% glass powder, a middle layer of pure silver paste, and an outer layer doped with 25 wt% titanium dioxide. The carbon dioxide adsorbent is 60-150 mesh Ca(OH)2 powder particles.

[0083] Operating conditions: For the adsorption zone, the third port 006 introduces 15% carbon dioxide / Ar at a flow rate of 1 L / min, allowing Ca(OH)₂ powder particles to adsorb carbon dioxide for 30 minutes at a temperature of 30°C. For the conversion zone, the second port 005 introduces 100% hydrogen at a flow rate of 1 L / min, and a 30 kV, 10 kHz plasma power supply is applied, with the plasma performing dielectric barrier discharge at a power of 20 W. For the purging and cooling zone, the first port 004 introduces 100% Ar for purging for 10 minutes, followed by 20 minutes of cooling. Each step is performed simultaneously for 30 minutes, then the rotor rotates 120° to switch between zones.

[0084] Results: After 100 cycles, the CO2 conversion rate remained above 90%, the CO selectivity was above 95%, and the reactor performance was stable with no significant deactivation or carbon buildup. Figure 6 As shown.

[0085] Example 2

[0086] This paper compares the experimental results of a single reaction mechanism based on the shape memory alloy wound wire-composite silver-based low-pressure electrode in this application with the experimental results of direct CO2 conversion in a single reactor using a traditional rod electrode in related technologies.

[0087] The high-voltage electrode of the dielectric tube is a wound wire electrode made of nickel-titanium shape memory alloy wire (A_f=100℃), and the low-voltage electrode is a gradient function silver-based composite electrode with an inner layer containing 30% glass powder, a middle layer of pure silver paste, and an outer layer doped with 25wt% titanium dioxide. The carbon dioxide adsorbent is 60-150 mesh Ca(OH)2 powder particles.

[0088] The traditional rod-shaped single-tube plasma reaction structure is the same as the experimental conditions described above, using a rod-shaped electrode as the high-voltage electrode, aluminum foil as the low-voltage electrode, and 60-150 mesh Ca(OH)2 powder particles as the carbon dioxide adsorbent.

[0089] Operating conditions: 100% carbon dioxide / hydrogen gas is introduced at a flow rate of 1 L / min, and plasma hydrogenation reaction is carried out under Ca(OH)2 powder particle filling conditions; a 30 kV, 10 kHz plasma power supply is applied, and the plasma performs dielectric barrier discharge with a power of 20 W.

[0090] Experimental results: The CO2 conversion rate of the single reactor based on shape memory alloy wound wire-composite silver-based telescopic electrode is much higher than that of other traditional reactors, with a carbon dioxide conversion rate of 58.5% and an energy cost of 43 MJ / mol. Compared with the traditional electrode reaction structure of stainless steel rod-copper mesh, the carbon dioxide conversion rate is increased by nearly 46% and the energy cost is reduced by 97 MJ / mol. The results are shown in Table 1 below.

[0091] Table 1

[0092]

[0093] While the present invention has been disclosed above, its scope of protection is not limited thereto. Those skilled in the art can make various changes and modifications without departing from the spirit and scope of the present invention, and all such changes and modifications will fall within the scope of protection of the present invention.

Claims

1. A high-voltage electrode for carbon dioxide capture and conversion, characterized in that, The high-voltage electrode comprises multiple shape memory alloy wires, which are wound and woven within a specified range to form a fluffy three-dimensional filament structure (201) to serve as the high-voltage electrode. The three-dimensional filament structure (201) has a first state and a second state. When the three-dimensional filament structure (201) is in the first state, the gap between adjacent shape memory alloy wires is larger than the gap between adjacent shape memory alloy wires when the three-dimensional filament structure (201) is in the second state. When the actual temperature of the high-voltage electrode is higher than its phase transition temperature, the high-voltage electrode shrinks from the first state to the second state.

2. The high voltage electrode for carbon dioxide capture conversion of claim 1, wherein, The shape memory alloy wire is a nickel-titanium-based shape memory alloy wire, and the phase transformation temperature of the nickel-titanium-based shape memory alloy wire is 80-120℃.

3. The high voltage electrode for carbon dioxide capture conversion of claim 2, wherein, The nickel content in the nickel-titanium based shape memory alloy wire is 50.8 at.%, and the diameter of the shape memory alloy wire is 100±50 μm.

4. The high voltage electrode for carbon dioxide capture conversion of claim 3, wherein, The method for preparing the shape memory alloy wire includes: solution treatment of the wire at 550°C for 20 minutes in a vacuum furnace followed by water quenching, then tightly winding it around a ceramic mandrel of the target diameter, constraining annealing at 450°C for 15 minutes, and then quenching.

5. The high voltage electrode for carbon dioxide capture conversion of claim 1, wherein, The gaps in the three-dimensional filament structure (201) are provided with adsorbent particles, and / or the surface of the high-voltage electrode is provided with a catalytic layer and an adsorption layer.

6. A reaction mechanism for carbon dioxide capture conversion, characterized by, The reaction mechanism includes: A medium tube (202) having a reaction chamber inside; A high-voltage electrode is disposed inside the reaction chamber, and the lead of the high-voltage electrode extends to the outside of the dielectric tube (202) and is connected to an external power supply (3) through a brush (007). The high-voltage electrode is a high-voltage electrode for carbon dioxide capture and conversion as described in any one of claims 1 to 5. A low-pressure electrode (203) is disposed on the outer wall of the dielectric tube (202), and the dimension of the low-pressure electrode (203) along the length direction of the dielectric tube (202) is the same as the dimension of the high-pressure electrode along the length direction of the dielectric tube (202). The low-voltage electrode (203) is connected to the grounding system via a grounding wire.

7. The reaction mechanism for carbon dioxide capture conversion according to claim 6, wherein, The low-voltage electrode (203) comprises, from the inside out, a bonding layer (401), a conductive layer (402), and a wear-resistant protective layer (403).

8. The reaction mechanism for carbon dioxide capture and conversion according to claim 7, characterized in that, The bonding layer (401) is a silver paste containing 20-30 wt% glass powder, and the conductive layer (402) is a pure silver paste; The wear-resistant protective layer (403) is a silver-based composite material doped with titanium dioxide.

9. The reaction mechanism for carbon dioxide capture and conversion according to claim 6, characterized in that, The inlet end of the medium pipe (202) is provided with an inlet flange (103), and the inlet flange (103) is connected to the medium pipe (202) by a fixing nut (108). The inlet flange (103) is provided with a power interface (101) at one end away from the medium pipe (202), and a high-pressure interface (102) is provided at the center of the inlet flange (103). An electrode sleeve (205) is provided inside the high-pressure interface (102), and the electrode sleeve (205) is coaxially arranged with the medium pipe (202). The electrode sleeve (205) contains an electrode bundle (204). One end of the electrode bundle (204) is led out via a power interface (101) for connecting to an external power source (3), and the other end of the electrode bundle (204) is used to connect to a three-dimensional filament structure (201) that serves as a high-voltage electrode.

10. A reaction apparatus, characterized in that, The reaction device is used to integrate carbon dioxide capture and utilization, and the reaction device includes a reaction mechanism for carbon dioxide capture and conversion as described in any one of claims 6 to 9.

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