Reactor for regenerating high-purity CO2 from waste gas based on electrochemistry and application of reactor

Abstract

The invention relates to an electrochemistry-based waste gas regeneration high-purity reactor and application thereof. The reactor comprises a cathode end plate, a gas diffusion cathode, a cation exchange membrane, an intermediate plate, a proton exchange membrane, an anode and an anode end plate which are sequentially arranged, the middle plate is provided with a middle cavity, a third feeding port and a third discharging port, and a solid electrolyte layer is arranged in the middle cavity; the cathode end plate is provided with a gas-liquid inlet, a first discharge port and a groove-shaped first flow channel, and the anode end plate is provided with a second feed port, a second discharge port and a groove-shaped second flow channel; the first discharging opening is connected with the third feeding opening; the third discharge hole is respectively connected with the gas-liquid inlet and the collecting device; the reactor runs at normal temperature and near normal pressure, can simultaneously realize high removal rate and efficient regeneration and enrichment in waste gas, has anti-poisoning capability, can realize industrial-grade current density, and has industrial application potential.

Description

Technical Field

[0001] This invention belongs to the field of electrochemical synthesis technology, specifically relating to a high-purity waste gas regeneration method based on electrochemistry. Reactors and their applications. Background Technology

[0002] With increasingly stringent global environmental regulations, ship exhaust emissions have become a focal point for the International Maritime Organization (IMO) and environmental agencies worldwide. Nitrogen oxides (NOx) produced by ships during navigation... ) and carbon oxides ( Harmful gases such as sulfur dioxide, nitrogen oxides, and particulate matter pose a significant threat to air quality, marine ecosystems, and climate change. The emission of these pollutants not only exacerbates air pollution and leads to global warming but may also have long-term negative impacts on marine life. Therefore, controlling ship exhaust emissions has become a crucial global task. Currently, ship exhaust treatment technologies mainly rely on conventional desulfurization and denitrification technologies, such as catalytic reduction and adsorption. These methods are ineffective in high-temperature and complex environments and are limited by volume and energy consumption within the high-density space of ships. Furthermore, traditional carbon capture methods are difficult to operate efficiently with low energy consumption. Therefore, there is an urgent need to develop an electrochemical-based high-purity exhaust gas regeneration method that can solve the above problems. The reactor. Summary of the Invention

[0003] The technical problem to be solved by this invention is to provide a high-purity waste gas regeneration method based on electrochemistry. The reactor and its application, which operates at near-normal temperature and pressure, can simultaneously remove impurities from waste gas. High removal rate and Highly efficient regeneration and enrichment, and possesses resistance It has strong poisoning resistance, can achieve industrial-grade current density, has high reactor stability, is compact, has controllable energy consumption, is suitable for enclosed high-density spaces, and has potential for industrial applications.

[0004] The technical solution adopted by the present invention to solve the above problems is as follows: On the one hand, this invention provides a high-purity waste gas regeneration method based on electrochemistry. The reactor comprises, in sequence, a cathode plate, a gas diffusion cathode, a cation exchange membrane, an intermediate plate, a proton exchange membrane, an anode, and an anode plate. The intermediate plate has an intermediate cavity containing a solid electrolyte layer. The cathode plate has a gas-liquid common inlet and a first outlet. A grooved first flow channel is located on the side of the cathode plate facing the gas diffusion cathode, and the gas-liquid common inlet and the first outlet are connected to the first flow channel. The anode plate has a second feed inlet and a second outlet. A grooved second flow channel is located on the side of the anode plate facing the anode, and the second feed inlet and the second outlet are connected to the second flow channel. The intermediate plate has a third feed inlet and a third outlet, which are connected to the intermediate cavity. The first outlet is connected to the third feed inlet via a pipeline. The third outlet is divided into two paths via a pipeline, one connected to the gas-liquid common inlet and the other connected to... The collection device is connected.

[0005] Understandably, appropriate pumping devices can be installed on pipelines to facilitate liquid transport.

[0006] The reactor utilizes the oxygen reduction reaction (ORR) and water oxidation reaction (OER) as the electrochemical reaction pair. A common gas-liquid inlet is used to introduce water and waste gas containing nitrogen oxides and carbon dioxide into the cathode chamber, which then flows into the first flow channel. Through the first flow channel, it contacts the gas diffusion cathode, where the oxygen in the waste gas is reduced to hydroxide ions. The intermediate chamber... The waste gas passes through the cation exchange membrane into the cathode chamber, forming an alkaline liquid which is then circulated back into the cathode chamber via the third outlet and a common gas-liquid inlet. The waste gas then comes into contact with the alkaline liquid. They are selectively absorbed and converted into carbonates / bicarbonates. Dissolved and transformed Alternatively, further electrochemical conversion can occur in the electrode microenvironment. The converted liquid enters the intermediate chamber through the first outlet and the third feed port. Water or electrolyte is introduced into the anode chamber through the second feed port and flows into the second channel, where it contacts the anode. The generated oxygen is discharged from the second outlet along with the water or electrolyte. It enters the intermediate chamber and reacts with carbonate / bicarbonate ions to produce carbon dioxide and water. The carbon dioxide then passes through... The collection device collects and generates After drying, the liquid can be compressed for storage or used on-site; the alkaline liquid is returned to the cathode chamber to achieve closed-loop circulation, low heat dependence at low grade, and controllable energy consumption.

[0007] The solid electrolyte layer in the reactor can reduce internal resistance and thus reduce production energy consumption.

[0008] The present invention relates to a high-purity waste gas regeneration method based on electrochemistry. The reactor operates at near-normal temperature and pressure, and in a closed-loop process of "waste gas absorption—electrochemical regeneration—product enrichment—recycling," it can simultaneously achieve the extraction of waste gas into the final product. High removal rate and Highly efficient regeneration and enrichment, and possesses resistance It has strong poisoning resistance, can achieve industrial-grade current density, has high reactor stability, is compact, has controllable energy consumption, is suitable for enclosed high-density spaces, and has potential for industrial applications.

[0009] Furthermore, the cathode end plate is made of stainless steel, the anode end plate is made of titanium, and the intermediate plate is made of plexiglass or polytetrafluoroethylene.

[0010] Furthermore, the gas diffusion cathode includes a gas diffusion layer and a Pt / C catalyst disposed on one side of the gas diffusion layer.

[0011] Furthermore, the gas diffusion layer is one of carbon paper, carbon felt, carbon cloth, or carbon fiber.

[0012] In the above technical solution, the gas diffusion layer material, as a carrier of the electrode catalyst material, can ensure uniform dispersion of the electrode catalyst material, while also maintaining good conductivity, and does not participate in the electrocatalytic reaction during the test.

[0013] The gas diffusion cathode can be prepared using conventional methods. Preferably, the preparation method for the gas diffusion cathode is as follows: A Pt / C catalyst is added to a certain volume of ethanol, mixed with a Nafion resin solution (1 wt%-10 wt%), and ultrasonically dispersed to obtain a bulk-uniform electrode ink. This electrode ink is then sprayed onto the surface of the gas diffusion layer and dried to obtain the gas diffusion cathode. The loading of the Pt / C catalyst on the gas diffusion layer is 1-2%. .

[0014] Furthermore, the anode includes a titanium felt and a [missing information - likely a component or element] disposed on one side of the titanium felt. layer.

[0015] The anode can be prepared using conventional methods.

[0016] Furthermore, the first flow channel is one of a serpentine flow channel, a double helix coiled flow channel, or a zigzag flow channel; and / or, the second flow channel is one of a serpentine flow channel, a double helix coiled flow channel, or a zigzag flow channel.

[0017] In the above technical solution, the shapes of the first and second flow channels are designed to uniformly and efficiently deliver reactants to the reaction sites (catalysts) of the electrodes and discharge products.

[0018] Furthermore, the effective reaction area of ​​the gas diffusion cathode and the anode is 0.5 × 0.5 - 10 × 10 .

[0019] Understandably, the effective reaction areas of the gas diffusion cathode and anode are adjustable, with an adjustable range of 0.5 × 0.5 - 10 × 10⁻⁶ depending on the reaction requirements. .

[0020] Furthermore, the thickness of the intermediate plate is 0.5-2.5 mm, and the cross-sectional area of ​​the intermediate cavity is 1×1-12×12 mm. The filling density of the solid electrolyte layer is 1.0-3.0. The filling thickness is 0.5-2.5 mm.

[0021] On the other hand, the present invention provides a reactor for regenerating high-purity waste gas using the above-mentioned reactor. Applications in [the field].

[0022] Furthermore, the present invention provides a reactor for use in carbonated beverage preparation equipment, gas fertilizer preparation equipment, refrigeration equipment, and... Applications in pneumoperitoneum machines.

[0023] The present invention has the following beneficial effects: The present invention relates to a high-purity waste gas regeneration method based on electrochemistry. The reactor operates at near-normal temperature and pressure, and in a closed-loop process of "waste gas absorption—electrochemical regeneration—product enrichment—recycling," it can simultaneously achieve the extraction of waste gas into the final product. High removal rate and Highly efficient regeneration and enrichment, and possesses resistance With its high poisoning resistance, industrial-grade current density, and reactor stability, this device is compact, energy consumption is controllable, and it is suitable for enclosed high-density spaces. It has potential for industrial applications, especially for large-scale ship exhaust gas absorption, making it a cost-effective, durable, and environmentally friendly solution. Attached Figure Description

[0024] Figure 1 This is a cross-sectional view and schematic diagram of the reactor in an embodiment of the present invention; Figure 2 This is a current and voltage curve of the reactor in an embodiment of the present invention; Figure 3 The reactor in the embodiment of the present invention Capture rate and carbonate formation rate graph; Figure 4 This is a diagram showing the nitrogen oxide removal rate of the reactor in an embodiment of the present invention; Figure 5This is a graph showing the energy consumption and current curves of the reactor in an embodiment of the present invention; The components include: cathode end plate 1, gas diffusion layer 21, Pt / C catalyst 22, cation exchange membrane 3, intermediate plate 4, proton exchange membrane 5, and titanium felt 61. Layer 62, anode plate 7, solid electrolyte layer 8, gas-liquid co-inlet 9, first discharge port 10, second feed port 11, second discharge port 12, third feed port 13, third discharge port 14. Detailed Implementation

[0025] To make the technical problems, solutions, and advantages of this invention clearer, a detailed description will be provided below with reference to specific examples. However, the scope of protection of this invention is not limited to the following specific embodiments. The described embodiments are merely some, not all, of the embodiments of this invention, and are not intended to limit the invention. Based on the embodiments of this invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this invention.

[0026] Unless otherwise defined, all technical terms used herein have the same meaning as commonly understood by those skilled in the art. The technical terms used herein are for the purpose of describing particular embodiments only and are not intended to limit the scope of the invention.

[0027] Unless otherwise specified, all raw materials, reagents, instruments and equipment used in this invention can be purchased from the market or prepared by existing methods.

[0028] Please see Figure 1 This invention provides a high-purity waste gas regeneration method based on electrochemistry. The reactor comprises, in sequence, a cathode plate 1, a gas diffusion cathode, a cation exchange membrane 3, an intermediate plate 4, a proton exchange membrane 5, an anode, and an anode plate 7; the intermediate plate 4 has an intermediate cavity (not shown in the figure), and a solid electrolyte layer 8 is disposed within the intermediate cavity; the cathode plate 1 has a gas-liquid common inlet 9 and a first outlet 10, and the side of the cathode plate 1 facing the gas diffusion cathode has a groove-shaped first flow channel (not shown in the figure), the gas-liquid common inlet 9 and the first outlet 10 are connected to the first flow channel; The anode plate 7 is provided with a second feed port 11 and a second discharge port 12. A groove-shaped second flow channel (not shown in the figure) is provided on the side of the anode-facing anode of the anode plate 7. The second feed port 11 and the second discharge port 12 are connected to the second flow channel. The intermediate plate 4 is provided with a third feed port 13 and a third discharge port 14, which are connected to the intermediate cavity. The first discharge port 10 is connected to the third feed port 13 via a pipeline. The third discharge port 14 is divided into two paths via a pipeline, one path connecting to the gas-liquid common inlet 9, and the other path connecting to… The collection device (not shown in the figure) is connected.

[0029] Specifically, the reactor is box-shaped, with a cross-section that is square, circular, or hexagonal, but not limited to these. It is understood that the layers within the reactor are tightly sealed together, and can be detachably connected by creating through holes in larger plates or layers and using threaded fittings. For ease of liquid transport, appropriate pumping devices (not shown in the figure) are installed on the pipeline.

[0030] Specifically, the cathode end plate 1 is made of stainless steel, the anode end plate 7 is made of titanium, and the intermediate plate 4 is made of polytetrafluoroethylene (PTFE). The gas diffusion cathode includes a gas diffusion layer 21 and a Pt / C catalyst 22 disposed on one side of the gas diffusion layer 21, wherein the gas diffusion layer 21 is made of carbon cloth. The anode includes a titanium felt 61 and a catalyst disposed on one side of the titanium felt 61. Layer 62; Cation exchange membrane 3 is an N2100TX proton exchange membrane; Solid electrolyte layer 8 is formed by filling the intermediate cavity with Dowex 50W X8 hydrogenated solid electrolyte; Proton exchange membrane 5 is a Nafion 117 proton exchange membrane; The first and second flow channels are both serpentine flow channels, and the regions where the two serpentine flow channels are located correspond to the gas diffusion cathode and anode, respectively; The effective reaction area of ​​the gas diffusion cathode and the anode is 10 × 10 The thickness of the intermediate plate 4 is 2mm, and the cross-sectional area of ​​the intermediate cavity is 4. The solid electrolyte layer 8 has a filling density of 1.5. The filling thickness is 2 mm.

[0031] The gas diffusion cathode is prepared by the following method: The gas diffusion cathode was prepared as follows: 3 mg of Pt / C (20 wt%) catalyst was added to 1 mL of ethanol containing 30 μL of 5 wt% Nafion, and ultrasonically dispersed for 1 h to obtain catalyst ink. The catalyst ink was then sprayed onto a carbon felt using a spray gun and dried at room temperature to obtain the gas diffusion cathode. The loading of Pt / C catalyst 22 on the gas diffusion layer 21 was 1... .

[0032] In this example, the reactor uses the oxygen reduction reaction (ORR) and water oxidation reaction (OER) as the electrochemical reaction pair. A common gas-liquid inlet (9) is used to introduce water and waste gas containing nitrogen oxides and carbon dioxide into the cathode chamber, which then flows into the first flow channel. Through the first flow channel, it contacts the gas diffusion cathode, where the oxygen in the waste gas is reduced to hydroxide ions. The intermediate chamber... The waste gas passes through the cation exchange membrane 3 and enters the cathode chamber, forming an alkaline liquid which is then circulated back into the cathode chamber through the third outlet 14 and the gas-liquid common inlet 9. The waste gas comes into contact with the alkaline liquid. They are selectively absorbed and converted into carbonates / bicarbonates. Dissolved and transformed Alternatively, further electrochemical conversion can be performed in the electrode microenvironment. The converted liquid enters the intermediate cavity through the first outlet 10 and the third feed port 13. Water or electrolyte is introduced into the anode chamber through the second feed port 11 and flows into the second channel, where it contacts the anode. The generated oxygen is discharged from the second outlet 12 along with the water or electrolyte. It enters the intermediate chamber and reacts with carbonate / bicarbonate ions to produce carbon dioxide and water. The carbon dioxide then passes through... The collection device collects the samples.

[0033] In this embodiment, a Bio-Logic VMP3 electrochemical workstation was used for performance testing, employing a two-electrode system; 4.8% The exhaust gas is simulated using 95.2% (by volume) air, with a nitrogen monoxide to nitrogen dioxide volume ratio of 1:1. The concentration is 1500 ppm, of which The concentration is 4.8%, and the flow rate of the waste gas introduced into the nine gas-liquid inlets is 5 L / min; 200 ml of 0.5 mol / L [agent / solution] is circulated between the intermediate chamber and the cathode chamber. The solution was kept at a flow rate of 0.9 mL / min; 0.3 M dilute sulfuric acid was supplied to the reactor as the anolyte through the second feed port 11 at a flow rate of 1. The drainage method test produces The quantity, and calculate Capture rate and carbonate formation rate; nitric oxide removal rate was tested using a NO gas detector, and energy consumption versus current curves were obtained using a galvanostatic method. Electrochemical performance test results are as follows: Figure 2-5 As shown.

[0034] Depend on Figure 2 It can be seen that when the test current is 100 mA, the corresponding voltage is 0.81 V; when the test current is 10 A, the corresponding voltage is 4.85 V, indicating that the reactor is capable of converting waste gas into pure gas. Its industrial potential.

[0035] Depend on Figure 3-4 It can be seen that within the test current range of 1-10A, The capture rate remained above 80%, while The removal rate gradually increased with increasing test current, and at a current greater than 6A, the removal rate for 1500 ppm was [value missing]. Achieving a removal rate of over 80%.

[0036] Depend on Figure 5 It can be seen that when the test current is 100 mA, the energy consumption of the reaction is only 169.5 KJ / mol, indicating that the reactor can achieve low energy consumption and has the potential for industrial application.

[0037] The present invention relates to a high-purity waste gas regeneration method based on electrochemistry. The reactor operates at near-normal temperature and pressure, and in a closed-loop process of "waste gas absorption—electrochemical regeneration—product enrichment—recycling," it can simultaneously achieve the extraction of waste gas into the final product. High removal rate and Highly efficient regeneration and enrichment, and possesses resistance With its high poisoning resistance, industrial-grade current density, and reactor stability, this device is compact, energy consumption is controllable, and it is suitable for enclosed high-density spaces. It has potential for industrial applications, especially for large-scale ship exhaust gas absorption, making it a cost-effective, durable, and environmentally friendly solution.

[0038] It is understood that the reactor of the present invention can be applied to carbonated beverage preparation equipment, gas fertilizer preparation equipment, refrigeration equipment, and... In pneumoperitoneum machines, but not limited to these.

[0039] The preferred embodiments of the present invention have been described in detail above. However, the present invention is not limited to the specific details in the above embodiments. Within the scope of the technical concept of the present invention, various simple modifications can be made to the technical solution of the present invention, and these simple modifications all fall within the protection scope of the present invention.

[0040] It should also be noted that the various specific technical features described in the above embodiments can be combined in any suitable manner without contradiction. To avoid unnecessary repetition, the present invention will not describe the various possible combinations separately.

[0041] Furthermore, various different embodiments of the present invention can be combined in any way, as long as they do not violate the spirit of the present invention, they should also be regarded as the content disclosed by the present invention.

Claims

1. An electrochemically based exhaust gas regeneration high purity reactor characterized by, The reactor comprises a cathode end plate, a gas diffusion cathode, a cation exchange membrane, an intermediate plate, a proton exchange membrane, an anode, an anode end plate arranged in sequence; the intermediate plate is provided with an intermediate cavity, and a solid electrolyte layer is arranged in the intermediate cavity; the cathode end plate is provided with a gas-liquid common inlet and a first discharge port, and a first flow channel in the form of a groove is arranged on the side of the cathode end plate facing the gas diffusion cathode, and the gas-liquid common inlet and the first discharge port are in communication with the first flow channel; the anode end plate is provided with a second feeding port and a second discharge port, and a second flow channel in the form of a groove is arranged on the side of the anode end plate facing the anode, and the second feeding port and the second discharge port are in communication with the second flow channel; the intermediate plate is provided with a third feeding port and a third discharge port, and the third feeding port and the third discharge port are in communication with the intermediate cavity; the first discharge port is connected with the third feeding port through a pipeline; the third discharge port is divided into two paths through a pipeline, one of which is connected with the gas-liquid common inlet, and the other of which is connected with a collecting device. The reactor comprises a cathode end plate, a gas diffusion cathode, a cation exchange membrane, an intermediate plate, a proton exchange membrane, an anode, an anode end plate arranged in sequence; the intermediate plate is provided with an intermediate cavity, and a solid electrolyte layer is arranged in the intermediate cavity; the cathode end plate is provided with a gas-liquid common inlet and a first discharge port, and a first flow channel in the form of a groove is arranged on the side of the cathode end plate facing the gas diffusion cathode, and the gas-liquid common inlet and the first discharge port are in communication with the first flow channel; the anode end plate is provided with a second feeding port and a second discharge port, and a second flow channel in the form of a groove is arranged on the side of the anode end plate facing the anode, and the second feeding port and the second discharge port are in communication with the second flow channel; the intermediate plate is provided with a third feeding port and a third discharge port, and the third feeding port and the third discharge port are in communication with the intermediate cavity; the first discharge port is connected with the third feeding port through a pipeline; the third discharge port is divided into two paths through a pipeline, one 2. The reactor of claim 1, wherein, The cathode end plate is made of stainless steel, the anode end plate is made of titanium, and the intermediate plate is made of organic glass plate or polytetrafluoroethylene plate.

3. The reactor of claim 1, wherein, The gas diffusion cathode comprises a gas diffusion layer and a Pt / C catalyst arranged on one side of the gas diffusion layer.

4. The reactor of claim 3, wherein, The gas diffusion layer is one of carbon paper, carbon felt, carbon cloth, and carbon fiber.

5. The reactor of claim 1, wherein The anode comprises a titanium felt and a layer of titanium oxide provided on one side of the titanium felt layer.

6. The reactor of claim 1, wherein, The first flow channel is one of a serpentine flow channel, a double-helix coiled flow channel, and a zigzag flow channel; and / or the second flow channel is one of a serpentine flow channel, a double-helix coiled flow channel, and a zigzag flow channel.

7. The reactor of claim 1, wherein The effective reaction area of the gas diffusion cathode and the anode is 0.5 x 0.5 - 10 x 10 .

8. The reactor according to claim 1 or 7, characterized in that The thickness of the intermediate plate is 0.5-2.5 mm, and the cross-sectional area of the intermediate cavity is 1x1-12x12 ; the filling density of the solid-state electrolyte layer is 1.0-3.0 g , and the filling thickness is 0.5-2.5 mm.

9. Use of a reactor according to any one of claims 1 to 8 for regenerating high purity CO2 from exhaust gases.

9. Use of a reactor according to any one of claims 1 to 8 for regenerating high purity CO2 from exhaust gases.

10. A reactor as described in any one of claims 1-8 in carbonated beverage preparation equipment, gas fertilizer preparation equipment, refrigeration equipment, and Applications in pneumoperitoneum machines.

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