A multifunctional electrocatalytic carbon dioxide reduction electrolytic cell device

Abstract

The present invention discloses a multifunctional electrocatalytic carbon dioxide reduction electrolytic cell device; including an anode chamber flow slot plate, a proton exchange membrane, a cathode chamber flow slot plate and an end plate component arranged in sequence; the end plate component is an end plate, or an end plate structural component having a carbon dioxide channel communicating with the cathode chamber and having a built-in working electrode. The present invention can select the slot plate assembly according to the needs to realize the switching of two electrolytic cells, wherein the S-shaped flow channel slot plate of the end plate structural component has a cross-like structure in the middle, forming four small windows, so that the gas introduced forms a disturbance residence time for a long time, and carbon paper is used as a gas diffusion layer in conjunction with the gas chamber flow channel slot plate and the cathode chamber flow slot plate to strengthen the diffusion of gas to carbon paper and reduce the penetration of liquid into the gas chamber. In addition, the anode / cathode chamber flow slot plates are both provided with gas-liquid inlets and outlets, and an external peristaltic pump can realize the real-time update of the electrolyte. At the same time, real-time online detection and analysis can be realized by gas chromatography and ion chromatography detection means.

Description

Technical Field

[0001] The present invention relates to the technical field of electrocatalytic carbon dioxide reduction, and relates to a multifunctional electrocatalytic carbon dioxide reduction (CO 2 The invention relates to an electrolytic cell device of a RR), and in particular to a multifunctional electrolytic cell device which can be freely assembled into a T-EC two-chamber (liquid-liquid) and a T-GDE three-chamber (gas-liquid-liquid) electrolytic cell device according to actual needs. Background Art

[0002] Electrocatalytic CO 2 Conversion into fuels or other useful chemicals is considered to be the most promising pathway for a controllable, environmentally friendly and efficient process. 2 The inherent chemical inertness and high bond energy make the activation process particularly difficult. 2 The electroreduction process is accompanied by H 2 The production of byproducts such as CO 2 Problems such as low Faraday efficiency of electroreduction.

[0003] The device of the electrocatalytic reaction is an important influencing factor, such as the pH of the electrolyte solution, the dissolution and diffusion of the gas, the separation and detection of the product, and the reaction efficiency. Therefore, the electrolytic cell device has a very important influence on the reaction. The commonly used H-type electrolytic cell is a typical two-chamber electrolytic cell, but the anode and cathode are far apart, the mass transfer distance is large, the energy loss is high, and the change of electrolyte solubility leads to low reaction efficiency. At the same time, the raw gas CO 2 It needs to be dissolved in the electrolyte, and the three-chamber electrolytic cell adds a gas chamber to achieve direct injection of the reaction gas. The commonly used three-chamber electrolytic cell is a modified fuel cell, with a small gas flow field and a small effective catalytic area, which will cause liquid seepage and lead to low reaction efficiency. Summary of the invention

[0004] In order to solve the above problems, the present invention provides a multifunctional electrolytic cell device for electrocatalytic carbon dioxide reduction; the slot plate assembly can be selected according to needs to realize the switching of the two electrolytic cells, which can greatly shorten the distance between the positive and negative electrodes, reduce the mass transfer distance and energy loss, update the electrolyte in real time, increase the gas flow field and residence time, increase the contact area, reduce the seepage phenomenon, and greatly enhance the catalytic reaction efficiency.

[0005] To achieve the above object, the technical solution adopted by the present invention is:

[0006] The present invention relates to a multifunctional electrocatalytic carbon dioxide reduction electrolytic cell device, the device comprising an anode chamber flow slot plate, a proton exchange membrane, a cathode chamber flow slot plate and an end plate component which are sequentially arranged and sealed by a sealing gasket;

[0007] A concave portion is provided on the anode chamber flow slot plate to form an anode chamber; a gas inlet and outlet, a liquid inlet and outlet, and two through holes with hollow screws are respectively provided on the anode chamber flow slot plate, and a counter electrode is inserted into one of the hollow screws; the gas inlet and outlet are arranged to enter from the bottom and exit from the top; the liquid in the anode chamber enters from the bottom and exits from the top;

[0008] A hollow cathode chamber is arranged in the cathode chamber flow slot plate, and a gas inlet and outlet, a liquid inlet and outlet and two through holes with hollow screws are respectively opened on the cathode chamber flow slot plate, and a reference electrode is inserted into one of the hollow screws; the gas and liquid in the cathode chamber both enter from the bottom and exit from the top;

[0009] The end plate component is an end plate, or an end plate structural component having a carbon dioxide channel communicating with the cathode chamber and capable of housing a working electrode.

[0010] As an embodiment of the present invention, when the end plate component is an end plate, the working electrode is inserted into another hollow screw of the cathode chamber flow slot plate. During operation, carbon dioxide is connected to the gas inlet and outlet according to the principle of bottom-in and top-out.

[0011] As an embodiment of the present invention, the end plate structural assembly is composed of an air chamber flow channel groove plate, a working electrode fixing plate and a working electrode;

[0012] The air chamber flow channel plate is provided with two layers of concave guide grooves: a rectangular guide groove and a gas guide groove, and the gas guide groove is provided at the lower layer of the rectangular guide groove; a block is provided in the gas guide groove to extend the residence time of the gas in the gas guide groove; a hole connected to the gas flow channel in the channel plate is respectively provided at the upper and lower parts of both sides of the air chamber flow channel plate (a gas flow quick connector is installed on the hole);

[0013] The positions on the working electrode fixing plate that contact the carbon paper diffusion layer on the working electrode are all provided with windows that communicate with the gas guide grooves;

[0014] The working electrode is fixed by the working electrode fixing plates on both sides and is placed in the grooves around the rectangular guide groove. The outer working electrode fixing plate is flush with the edge surface of the air chamber flow channel groove plate.

[0015] As an embodiment of the present invention, the gas guide groove is an S-shaped guide groove; the part of the S-shaped guide groove in contact with the carbon paper diffusion layer on the working electrode has a cross-like structure, forming four small window flow channels; the position on the working electrode fixing plate in contact with the carbon paper diffusion layer on the working electrode is provided with four small windows corresponding to the four small window flow channels in the S-shaped guide groove.

[0016] As an embodiment of the present invention, the working electrode is composed of an electrode sheet and a carbon paper diffusion layer, and the electrode sheet is a titanium plate with a window in the middle for placing the carbon paper diffusion layer.

[0017] As an embodiment of the present invention, a protruding slender titanium plate is provided on the upper part of the electrode sheet; a groove for placing the slender titanium plate is also provided above the rectangular guide groove on the air chamber flow channel plate.

[0018] As an embodiment of the present invention, two holes connected to the anode chamber are respectively opened on the upper and lower parts of one side of the anode chamber circulation slot plate, and the lower hole is installed with a gas circulation quick connector, and the upper hole is installed with a liquid circulation self-locking connector, and a hole connected to the anode chamber is opened in the lower part of the other side, and a liquid circulation self-locking connector is installed; three holes connected to the anode chamber are opened above the anode chamber circulation slot plate, and two hollow screws with sealing rings and a gas circulation quick connector are respectively installed; the counter electrode is inserted into one of the hollow screws with a sealing ring.

[0019] As an embodiment of the present invention, two holes communicating with the cathode chamber are respectively opened on the upper and lower parts of one side of the cathode chamber circulation slot plate, and a gas circulation quick connector is installed in the lower hole, and a liquid circulation self-locking connector is installed in the upper hole; a hole communicating with the cathode chamber is opened in the lower part of the other side, and a liquid circulation self-locking connector is installed; three holes communicating with the cathode chamber are opened above the cathode chamber circulation slot plate, and two hollow screws with sealing rings and a gas circulation quick connector are respectively installed, and a reference electrode can be inserted into one of the hollow screws with a sealing ring.

[0020] As one embodiment of the present invention, the cathode chamber flow slot plate and / or the anode chamber flow slot plate are connected to the peristaltic pump via a liquid flow self-locking joint.

[0021] As an embodiment of the present invention, the upper gas flow quick connector on the cathode chamber flow slot plate is connected to a gas chromatograph to perform real-time online detection and analysis of gas products.

[0022] As an embodiment of the present invention, the upper liquid circulation self-locking joint on the cathode chamber circulation slot plate is connected to the outlet device, and the circulating outlet liquid is regularly extracted to detect the liquid product through ion chromatography.

[0023] Compared with the prior art, the present invention has the following beneficial effects:

[0024] 1. It can be freely assembled into two types of electrolytic cells: T-EC two-chamber (liquid-liquid) and T-GDE three-chamber (gas-liquid-liquid) according to actual needs;

[0025] 2. The T-GDE three-chamber electrolytic cell adds a gas chamber, which not only realizes direct sampling of the reaction gas, but also increases the gas flow field and residence time, increases the contact area, reduces the seepage phenomenon, and greatly enhances the efficiency of the catalytic reaction; specifically, since there are four small windows in the middle of the S-shaped flow channel of the gas chamber, when used in conjunction with the carbon paper diffusion layer loaded with the catalyst, it can effectively increase the contact area and increase the retention time, ensuring that the gas can fully diffuse to the catalyst surface. At the same time, when assembled with the working electrode, it can just keep the entire cathode gas chamber flow channel plate flat, and only retain the four small windows in contact with the electrolyte of the cathode liquid chamber flow slot plate. The remaining area of ​​the gas and liquid chambers is completely fitted, effectively reducing the seepage phenomenon;

[0026] 3. The cathode liquid chamber flow slot plate and the anode liquid chamber flow slot plate are separated only by a proton exchange membrane (such as Nafion117 membrane). When used together, the distance between the positive and negative electrodes can be greatly shortened without interfering with each other, which greatly shortens the mass transfer distance and reduces unnecessary energy loss.

[0027] 4. The cathode liquid chamber flow slot plate and the anode liquid chamber flow slot plate are both equipped with gas-liquid inlet and outlet joints. The gas product can be directly connected to the gas chromatograph, and real-time online detection and analysis can be achieved through gas chromatography and ion chromatography detection methods; an external peristaltic pump can realize the continuous renewal of electrolyte and the timely discharge of liquid products to prevent changes in electrolyte solubility or contamination. By improving these conditions, electrode poisoning can be effectively avoided, and the electrocatalytic CO 2 Reduction efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 is a schematic diagram of a three-chamber T-GDE of a specific embodiment of the present invention;

[0029] Figure 2 is a schematic diagram of a two-chamber T-EC according to a specific embodiment of the present invention;

[0030] Figure 3 2 is a schematic diagram of the structure of the cathode gas chamber flow channel plate in a specific embodiment of the present invention;

[0031] Among them, 1 is the anode chamber flow slot plate, 2 is the proton exchange membrane, 3 is the cathode chamber flow slot plate, 4 is the cathode chamber, 5 is the gas chamber flow channel slot plate, 6 is the first working electrode fixing plate, 7 is the working electrode, 8 is the second working electrode fixing plate, 9 is the sealing gasket, 10 is the electrolyte circulation valve, 11 is the counter electrode, 12 is the reference electrode, 13 is the end plate, 14 is the rectangular guide groove, 15 is the S-shaped guide groove, and 16 is the groove. DETAILED DESCRIPTION

[0032] In order to make the technical problems, technical solutions and beneficial effects to be solved by the present invention clearer and more understandable, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments.

[0033] Example

[0034] See also Figure 1-3 As shown, this embodiment provides an electrocatalytic carbon dioxide reduction (CO 2 The electrolytic cell of RR can be assembled into a T-GDE three-chamber electrolytic cell and a T-EC two-chamber electrolytic cell according to the use requirements.

[0035] like Figure 1 As shown, the T-GDE three-chamber electrolytic cell is mainly composed of a gas chamber flow channel plate 5, a working electrode fixing plate (a first working electrode fixing plate 6, a second working electrode fixing plate 8), an electrode sheet 7, a carbon paper diffusion layer, a proton exchange membrane 2, a cathode chamber flow channel plate 3 and an anode chamber flow channel plate 1; wherein,

[0036] The air chamber flow channel plate 5 is provided with two layers of concave guide grooves ( Figure 3 ): rectangular flow guide groove 14 and gas flow guide groove (S-shaped flow guide groove 15), the S-shaped flow guide groove 15 is arranged at the lower layer of the rectangular flow guide groove 14; the S-shaped flow guide groove 15 has a cross-like structure at the part in contact with the carbon paper diffusion layer on the working electrode 7, forming four small windows, so that the gas stays in the gas chamber for a long enough time and fully diffuses to the catalyst layer on the carbon paper diffusion layer. This cross-like structure can be: a downward first protrusion is arranged at the bottom of the upper flow channel of the part in contact with the carbon paper diffusion layer on the working electrode 7 on the S-shaped flow guide groove 15, a first recess is arranged in the middle of the middle flow channel, and the first protrusion and the bottom of the first recess have a gap for gas flow; an upward second protrusion is arranged at the end of the middle flow channel, and the second protrusion and the bottom of the upper flow channel have a gap for gas flow; a second recess is arranged in the middle of the lower flow channel, and a downward third protrusion is arranged at the bottom of the first recess, and the third protrusion and the bottom of the second recess have a gap for gas flow. The first working electrode fixing plate 6, the working electrode 7 and the second working electrode fixing plate 8 are sequentially placed on the grooves around the rectangular flow guide groove 14, just tightly fitting the grooves and leveling with the edge of the gas chamber flow channel groove plate 5, effectively reducing the leakage of the cathode liquid chamber into the gas chamber; the rectangular flow guide groove 14 on the gas chamber flow channel groove plate 5 is also provided with a groove 16 protruding from the upper part of the thin and long titanium plate for placing the electrode sheet (the working electrode 7 is composed of an electrode sheet and a carbon paper diffusion layer, and the electrode sheet is a titanium plate with a window for placing the carbon paper diffusion layer in the middle). A hole connected to the S-shaped flow channel is opened on both sides of the gas chamber flow channel groove plate 5, one above and one below, and a gas flow quick connector is installed on the hole.

[0037] Four small windows corresponding to the four small windows in the S-shaped guide groove 15 are formed at the positions of the first and second working electrode fixing plates 6 and 8 that contact the carbon paper diffusion layer on the working electrode 7 .

[0038] The electrode sheet is a titanium plate with a square window in the middle and a long and thin strip protruding from the top. The carbon paper diffusion layer is carbon paper containing a catalyst; the carbon paper diffusion layer is placed in the square window of the electrode sheet to form a working electrode 7. In the T-GDE three-chamber electrolytic cell, the carbon paper diffusion layer is close to the side of the gas chamber flow channel plate 5, and has a CO composed of the S-shaped flow channel 15 of the gas chamber flow channel plate 5 and the four small windows of the first working electrode fixing plate 6. 2 Channel; CO 2 The carbon paper diffusion layer undergoes a reduction reaction to form CO 2 Intermediate, CO 2 The intermediate enters the cathode chamber 4 provided in the cathode chamber flow slot plate 3 through the four small windows of the second working electrode fixing plate 8 .

[0039] The cathode chamber flow slot plate 3 is provided with a hollow cathode chamber 4 for storing the cathode electrolyte (e.g., 0.5M KHCO 3 ) and to accommodate CO 2 Intermediate. Two holes are opened on one side of the cathode chamber flow slot plate 3, one above and one below, which are connected to the cathode chamber 4. The lower hole is installed with a gas flow quick connector, and the upper hole is installed with a liquid flow self-locking connector (which can be connected to the electrolyte circulation valve 10). A hole is opened at the lower part of the other side, which is connected to the cathode chamber 4 and is installed with a liquid flow self-locking connector; three holes are opened above the cathode chamber flow slot plate 3, which are connected to the cathode chamber 4, and two hollow screws with sealing rings and a gas flow quick connector are installed respectively; gas-liquid (cathode electrolyte solution and CO 2 ) enter the cavity from below and flow out from above respectively. The self-locking joint is a self-locking device that allows flow when a catheter is inserted and prevents flow when the catheter is removed.

[0040] In the T-GDE three-chamber electrolytic cell, the cathode chamber 4 (i.e., the chamber inside the cathode chamber flow slot plate) only needs to place the reference electrode 12, that is, the reference electrode 12 (a saturated Ag / AgCl electrode is selected) is inserted into a hollow screw with a sealing ring above the cathode chamber flow slot plate 3.

[0041] After placing the working electrode 7 fixed by the first and second working electrode fixing plates 6 and 8 on the gas chamber flow channel plate 5, the gas chamber flow channel plate 5 and the cathode chamber flow channel plate 3 are sealed by a sealing gasket 9; the sealing gasket 9 is provided with a window matched with the size of the cathode chamber 4 of the cathode chamber flow channel plate 3.

[0042] A recess is provided on the anode chamber circulation slot plate 1 to form an anode chamber; it is used to store the anode electrolyte (such as 0.5MKOH). Two holes connected to the anode chamber are opened on one side of the anode chamber circulation slot plate 1, one above and one below. The lower hole is installed with a gas circulation quick connector, and the upper hole is installed with a liquid circulation self-locking connector (which can be connected to the electrolyte circulation valve 10). A hole connected to the anode chamber is opened below the other side, and a liquid circulation self-locking connector is installed; three holes connected to the anode chamber are opened above the anode chamber circulation slot plate 1, and two hollow screws with sealing rings and a gas circulation quick connector are installed respectively. Gas (the air hole is not used temporarily and is designed for subsequent development) and liquid (anode electrolyte) enter the cavity from the bottom and flow out of the top respectively. The self-locking connector is a self-locking device that allows circulation when a catheter is inserted, and cannot circulate when the catheter is pulled out.

[0043] In the T-GDE three-chamber electrolytic cell, the anode chamber (i.e., the chamber inside the anode chamber flow slot plate) only needs to place the counter electrode 11 (a platinum wire electrode is selected), that is, the counter electrode 11 is inserted into a hollow screw with a sealing ring above the anode chamber flow slot plate 1.

[0044] The cathode chamber flow slot plate 3 and the anode chamber flow slot plate 1 are separated only by the proton exchange membrane 2, so that the positive and negative poles are as close as possible without interfering with each other, effectively reducing the mass transfer distance and energy loss. The proton exchange membrane 2 is a Nafion117 membrane. A sealing gasket 9 is provided on both sides of the proton exchange membrane 2. The cathode chamber flow slot plate 3, the proton exchange membrane 2 and the anode chamber flow slot plate 1 are bonded together through the sealing gasket 9 to ensure the sealing of the entire device. The cathode chamber 4 of the cathode chamber flow slot plate 3 and the anode chamber of the anode chamber flow slot plate 1 are of the same size; the sealing gasket 9 is cut from a corresponding silicone sheet, and a window adapted to the size of the cathode chamber 4 or the anode chamber is provided on the sealing gasket 9.

[0045] In addition, the cathode chamber circulation slot plate 3 and the anode chamber circulation slot plate 1 can be connected to the peristaltic pump via the provided liquid circulation self-locking joint, and the electrolyte solution is continuously introduced and updated in real time to ensure the same concentration of the reaction electrolyte solution and the timely discharge of the liquid reduction product to prevent electrode poisoning and electrolyte contamination, and can also be collected and detected and analyzed using ion chromatography.

[0046] The structure of the T-EC two-chamber electrolytic cell is as follows Figure 2 , which consists of an auxiliary chamber plate (end plate 13), a proton exchange membrane 2, a cathode chamber flow slot plate 3 and an anode chamber flow slot plate 1. The main difference between it and the T-GDE three-chamber electrolytic cell is:

[0047] The side of the cathode chamber flow slot plate 3 facing away from the anode chamber flow slot plate 1 is sealed with the auxiliary chamber plate (also called the end plate 13) through the sealing gasket 9. In addition, the working electrode 11 and the reference electrode 12 are placed in the cathode chamber 4, that is, an electrode clip with carbon paper is inserted into a hollow screw with a sealing ring above the cathode chamber flow slot plate 3 as the working electrode 11, and a saturated Ag / AgCl electrode is inserted into another hollow screw with a sealing ring as the reference electrode 12. In addition, CO 2 The gas flow quick connector is connected to the cathode chamber flow slot plate 3 according to the principle of bottom-in and top-out.

[0048] The specific operations are as follows:

[0049] Take the T-GDE three-chamber electrolytic cell as an example

[0050] According to the experimental requirements, select the T-GDE three-chamber electrolytic cell. First, insert 10 cm long cap screws into the 7 holes on the anode chamber flow slot plate to fix them. Then use two sealing gaskets to clamp the Nafion 117 membrane and place it above the anode chamber flow slot plate. This step is the most critical step to determine whether the anode chamber and cathode chamber are permeable. Then fix the carbon paper diffusion layer on the electrode sheet to assemble it into a working electrode, and tighten the working electrode fixing plates on both sides and place them on the top layer. Put gaskets on the screws and tighten the screw caps. Then insert the counter electrode into the empty screw with a sealing ring in the middle of the anode chamber flow slot plate, and insert the reference electrode into the empty screw with a sealing ring on the cathode chamber flow slot plate.

[0051] Furthermore, the gas flow quick connector of the gas chamber S-shaped flow channel plate is connected to the CO according to the principle of bottom-in and top-out. 2 Finally, the liquid circulation self-locking joints of the cathode chamber circulation slot plate and the anode chamber circulation slot plate are connected to the peristaltic pump to update the electrolyte solution in real time, and the gas circulation quick joint of the cathode chamber circulation slot plate is connected to the gas chromatograph for real-time online detection and analysis of the product. For the test of liquid products, the circulating export liquid can be regularly extracted for detection through ion chromatography.

[0052] The operating principle is as follows: CO 2 According to the principle of bottom-in and top-out, the S-shaped flow channel plate connected to the gas chamber forms a diversion channel in the concave diversion groove of the two layers of the S-shaped flow channel, and the four small windows on the working electrode fixing plate in contact with the carbon paper diffusion layer stay long enough to fully diffuse to the catalyst layer on the carbon paper, and a reduction reaction occurs to form CO 2 At this time, an oxidation reaction occurs at the anode to generate protons H, which diffuse through the Nafion 117 membrane to the cathode chamber and react with CO on the catalyst surface. 2The intermediates combine to generate reduction products such as CO and formic acid. The gaseous products generated after reduction continue to diffuse into the concave guide groove of the S-shaped flow channel plate of the gas chamber and are discharged from the upper port. The liquid products remain in the cathode chamber and are discharged through the upper port of the peristaltic pump connected to the cathode chamber flow channel plate. 2 Restore process.

[0053] Take the T-EC two-chamber electrolytic cell as an example

[0054] According to the experimental requirements, select the T-EC two-chamber electrolytic cell. First, insert 10 cm long cap screws into the 7 holes on the anode chamber flow slot plate to fix them. Then use two sealing gaskets to clamp the Nafion 117 membrane and place it on top of the anode chamber flow slot plate. The above steps are the same as the assembly of the T-GDE three-chamber electrolytic cell. Then install the electrode clamp on the empty screw with a sealing ring in the middle of the cathode chamber flow slot plate, clamp the carbon paper sprayed with catalyst, put a sealing gasket on it and place the auxiliary chamber plate on the top layer. Then put gaskets on the screws and screw on the screw caps. Then insert the counter electrode into the empty screw with a sealing ring in the middle of the anode chamber flow slot plate, and insert the reference electrode into another empty screw with a sealing ring on the cathode chamber flow slot plate.

[0055] Further, connect the gas flow quick connector of the cathode chamber flow slot plate to the CO 2 Gas pipeline. Finally, the liquid circulation self-locking joints of the cathode chamber circulation slot plate and the anode chamber circulation slot plate are connected to the peristaltic pump to update the electrolyte solution in real time, and the quick joints of the cathode chamber circulation slot plate gas circulation are connected to the gas chromatograph for real-time online detection and analysis of the product. For the test of liquid products, the circulating export liquid can be regularly extracted for detection through ion chromatography.

[0056] The operating principle is as follows: CO 2 The gas flow quick connector connected to the cathode chamber flow slot plate according to the principle of bottom-in and top-out is first dissolved in the electrolyte solution, then diffused to the surface of the working electrode catalyst, and a reduction reaction occurred to form CO 2 At this time, an oxidation reaction occurs at the anode to generate protons H, which pass through the Nafion 117 membrane and diffuse to the catalyst surface to react with CO 2 The intermediates combine to generate reduction products such as CO and formic acid. The gaseous products generated after reduction continue to diffuse and are discharged through the quick connector for gas circulation above the cathode chamber flow slot plate. The liquid products remain in the cathode chamber and are discharged through the upper port of the peristaltic pump connected to the cathode chamber flow slot plate. 2 Restore process.

[0057] Separation and detection of products: When electrolysis is performed under set voltage conditions, the gas chromatograph is sampled 5ul each time, and the test is performed three times in total. The product and content are determined according to the position of the gas chromatographic peak to detect the gas phase product. At the same time, the cathode electrolyte circulated by the peristaltic pump is collected at the same time interval, and the liquid product is detected by ion chromatography.

[0058] In summary, the present invention provides a multifunctional electrocatalytic carbon dioxide reduction electrolytic cell device; the trough plate assembly can be selected according to the needs to realize the switching of two electrolytic cells, wherein the first gas chamber S-type flow channel trough plate has a cross-like structure in the middle, forming four small windows, so that the gas introduced forms a disturbance and stays for a long time, and carbon paper is used as a gas diffusion layer in conjunction with the first gas chamber S-type flow channel trough plate and the second cathode liquid chamber flow trough plate to strengthen the diffusion of gas to carbon paper and reduce the penetration of liquid into the gas chamber. The second cathode liquid chamber flow trough plate and the third anode liquid chamber flow trough plate are separated only by a proton exchange membrane, and when used in conjunction, the distance between the positive and negative poles can be greatly shortened without interfering with each other, reducing the mass transfer distance and energy loss. In addition, both liquid chamber flow trough plates are provided with gas and liquid inlets and outlets, and an external peristaltic pump can realize the real-time update of the electrolyte, effectively avoiding electrode poisoning, and the reduction product can be discharged in time, and real-time online detection and analysis can be realized by gas chromatography and ion chromatography detection means.

[0059] The above describes the specific embodiments of the present invention. It should be understood that the present invention is not limited to the above specific embodiments, and those skilled in the art may make various modifications or variations within the scope of the claims, which do not affect the essence of the present invention.

Claims

1. A multifunctional electrocatalytic carbon dioxide reduction electrolytic cell device, characterized in that: The device comprises an anode chamber flow slot plate, a proton exchange membrane, a cathode chamber flow slot plate and an end plate component which are arranged in sequence and sealed by a sealing gasket; A concave portion is provided on the anode chamber flow slot plate to form an anode chamber; a gas inlet and outlet, a liquid inlet and outlet and two through holes with hollow screws are respectively provided on the anode chamber flow slot plate, and a counter electrode is inserted into one of the hollow screws; the gas inlet and outlet are arranged to enter from the bottom and exit from the top; the liquid in the anode chamber enters from the bottom and exits from the top; A hollow cathode chamber is arranged in the cathode chamber flow slot plate, and a gas inlet and outlet, a liquid inlet and outlet and two through holes with hollow screws are respectively opened on the cathode chamber flow slot plate, and a reference electrode is inserted into one of the hollow screws; the gas and liquid in the cathode chamber both enter from the bottom and exit from the top; The end plate component is an end plate structural component having a carbon dioxide channel communicating with the cathode chamber and capable of housing a working electrode; The end plate structural assembly is composed of an air chamber flow channel groove plate, a working electrode fixing plate and a working electrode; The air chamber flow channel plate is provided with two layers of concave guide grooves: a rectangular guide groove and a gas guide groove, and the gas guide groove is provided at the lower layer of the rectangular guide groove; a block is provided in the gas guide groove to extend the residence time of the gas in the gas guide groove; a hole connected to the gas flow channel in the channel plate is respectively provided at the upper and lower parts of both sides of the air chamber flow channel plate; The positions on the working electrode fixing plate that contact the carbon paper diffusion layer of the working electrode are all provided with windows that communicate with the gas guide grooves; The working electrode is fixed by the working electrode fixing plates on both sides and is placed in the grooves around the rectangular flow guide groove. The outer working electrode fixing plate is flush with the edge surface of the gas chamber flow channel groove plate. The gas guide groove is an S-shaped guide groove; the portion of the S-shaped guide groove in contact with the carbon paper diffusion layer of the working electrode has a cross-like structure, forming four small window flow channels; the position of the working electrode fixing plate in contact with the carbon paper diffusion layer of the working electrode is provided with four small windows corresponding to the four small window flow channels in the S-shaped guide groove; Two holes communicating with the cathode chamber are respectively provided at the upper and lower parts of one side of the cathode chamber circulation slot plate, wherein a gas circulation quick connector is installed at the lower hole and a liquid circulation self-locking connector is installed at the upper hole; a hole communicating with the cathode chamber is provided at the lower part of the other side, wherein a liquid circulation self-locking connector is installed; three holes communicating with the cathode chamber are provided above the cathode chamber circulation slot plate, wherein two hollow screws with sealing rings and a gas circulation quick connector are respectively installed, wherein a reference electrode can be inserted into one of the hollow screws with a sealing ring.

2. The multifunctional electrocatalytic carbon dioxide reduction electrolytic cell device according to claim 1, characterized in that: The working electrode is composed of an electrode sheet and a carbon paper diffusion layer. The electrode sheet is a titanium plate with a window in the middle for placing the carbon paper diffusion layer.

3. The multifunctional electrocatalytic carbon dioxide reduction electrolytic cell device according to claim 2, characterized in that: A protruding slender titanium plate is provided on the upper part of the electrode sheet; a groove for placing the slender titanium plate is also provided above the rectangular guide groove on the air chamber flow channel plate.

4. The multifunctional electrocatalytic carbon dioxide reduction electrolytic cell device according to claim 1, characterized in that: Two holes connected to the anode chamber are respectively provided at the upper and lower parts of one side of the anode chamber circulation slot plate, and a gas circulation quick connector is installed at the lower hole, and a liquid circulation self-locking connector is installed at the upper hole; a hole connected to the anode chamber is provided at the lower part of the other side, and a liquid circulation self-locking connector is installed; three holes connected to the anode chamber are provided above the anode chamber circulation slot plate, and two hollow screws with sealing rings and a gas circulation quick connector are respectively installed; a counter electrode is inserted into one of the hollow screws with a sealing ring.

5. The multifunctional electrocatalytic carbon dioxide reduction electrolytic cell device according to claim 3 or 4, characterized in that: The cathode chamber flow slot plate and / or the anode chamber flow slot plate are connected to the peristaltic pump via a liquid flow self-locking joint.

6. The multifunctional electrocatalytic carbon dioxide reduction electrolytic cell device according to claim 5, characterized in that: The upper gas flow quick connector on the cathode chamber circulation slot plate is connected to the gas chromatograph to detect and analyze the gas products in real time online; and / or, the upper liquid flow self-locking connector on the cathode chamber circulation slot plate is connected to the derivation device to regularly extract the circulating derivation liquid to detect the liquid products through ion chromatography.

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