Alkaline electrolytic cell electrode preparation system and method

Abstract

The invention discloses an alkaline electrolytic cell electrode preparation system and method, and the system comprises an electrolytic cell, a circulating pump, a precursor flow regulator, an anode side gas-liquid separator, a cathode side gas-liquid separator, an anode side gas flow regulator and a cathode side gas flow regulator, the electrolytic bath is used for installing the pretreated electrode base bodies at the anode position and the cathode position correspondingly. By adopting the scheme provided by the embodiment of the invention, the electrode is prepared on the basis of the electrolytic bath, the gas-liquid separator, the circulating pump and other equipment of the alkaline electrolytic hydrogen production system, the size of the electrode can be matched with the sizes of the cathode and the anode in the electrolytic bath, simultaneous preparation of the full-size industrial anode and the cathode can be realized, and the production cost of the electrode is remarkably reduced; and a plurality of electrode substrates can be inserted into the electrolytic bath at one time, so that a plurality of full-size industrial alkaline electrodes can be prepared at one time, and the method is suitable for batch production of electrodes required by alkaline electrolysis hydrogen production equipment.

Description

Technical Field

[0001] The present invention relates to the technical field of electrolytic hydrogen production, and in particular to a system and method for preparing alkaline electrolytic cell electrodes. Background Art

[0002] Water electrolysis hydrogen production technology has become the mainstream in the field of hydrogen production technology due to its advantages such as a wide range of raw material sources, efficient use of waste wind energy and electricity, and small equipment footprint. Among the many water electrolysis hydrogen production technologies, alkaline water electrolysis hydrogen production technology has gradually gained favor in the industry due to its high technical maturity, low equipment cost, and ability to achieve large-scale hydrogen production. At present, the maximum hydrogen production capacity of a single alkaline electrolyzer with mature technology can reach 2000Nm 3 / h, such as Hydrogen Age Company and China Shipbuilding Industry Corporation 718th Research Institute have launched single hydrogen production capacity of 2000Nm 3 / h alkaline electrolyzer.

[0003] Compared with simply increasing the size of the electrolytic cell, it is more feasible and economical to improve the performance of the electrolytic cell and reduce its cost by developing high-performance electrodes. However, the preparation process of large-scale electrodes is limited. At present, the preparation of electrolytic cell electrodes still mainly relies on traditional thermal spraying, electrodeposition and thermal decomposition methods. However, the above methods have the problems of high cost and large loss of raw materials. The hydrothermal method is a promising electrode preparation method, which can produce electrodes with low production cost and better performance. However, it is affected by the electrode preparation equipment and electrode preparation method. It is still difficult to prepare full-size industrial electrolytic cell electrodes (electrodes with a diameter of 1m-2m), so it is difficult to apply it to the preparation process of industrial electrodes. Summary of the Invention

[0004] The object of the present invention is to provide a system and method for preparing alkaline electrolytic cell electrodes to at least partially solve the above-mentioned problems of the prior art.

[0005] To achieve the above object, the present invention provides an alkaline electrolytic cell electrode preparation system, comprising an electrolytic cell 1, a circulation pump 2, a precursor flow regulator 3, an anode side gas-liquid separator 4, a cathode side gas-liquid separator 5, an anode side gas flow regulator 6, and a cathode side gas flow regulator 7, wherein

[0006] Electrolytic cell 1, used for installing pre-treated electrode substrates at the anode position and cathode position respectively;

[0007] The inlet of the electrolytic cell 1 is connected to the circulation pump 2, which is connected to the precursor flow regulator 3, the anode-side gas-liquid separator 4, and the cathode-side gas-liquid separator 5, and receives the pre-configured precursor solution input through the precursor flow regulator 3, and the circulating precursor solution output from the anode-side gas-liquid separator 4 and the cathode-side gas-liquid separator 5;

[0008] The anode side outlet of the electrolytic cell 1 is connected to the upper part of the anode side gas-liquid separator 4, the cathode side outlet is connected to the upper part of the cathode side gas-liquid separator 5, and the bottom outlets of the anode side gas-liquid separator 4 and the cathode side gas-liquid separator 5 are respectively connected to the circulation pump 2;

[0009] The anode side gas-liquid separator 4 is connected to the anode side gas flow regulator 6, and the cathode side gas-liquid separator 5 is connected to the cathode side gas flow regulator 7. The anode side gas flow regulator 6 and the cathode side gas flow regulator 7 are used to introduce gas into the anode side gas-liquid separator 4 and the cathode side gas-liquid separator 5, respectively, to adjust the gas environment and pressure of the precursor solution.

[0010] Preferably, the system further comprises an anode side pressure regulator 8 and a cathode side pressure regulator 9;

[0011] The anode side pressure regulator 8 is connected to the anode side gas-liquid separator 4 and is used to adjust the pressure in the anode side gas-liquid separator 4;

[0012] The cathode side pressure regulator 9 is connected to the cathode side gas-liquid separator 5 and is used to regulate the pressure in the cathode side gas-liquid separator 5 .

[0013] Preferably, the system further includes a heating system for heating the precursor solution in the anode-side gas-liquid separator 4 and the cathode-side gas-liquid separator 5 to maintain the temperature of the precursor solution within a preset range.

[0014] Preferably, the system heating system includes a circulating water system.

[0015] Preferably, the precursor solution comprises a metal salt solution.

[0016] Preferably, the precursor solution includes an alcohol solution or a H2O2 solution.

[0017] Preferably, the anode side gas flow regulator 6 and the cathode side gas flow regulator 7 are used to introduce oxygen, nitrogen, and / or compressed air into the anode side gas-liquid separator 4 and the cathode side gas-liquid separator 5, respectively.

[0018] Preferably, the precursor flow regulator 3 is further used to: drain the precursor solution after a preset reaction time, and introduce clean water for cleaning.

[0019] Preferably, a distance is left between the electrode substrate and the diaphragm in the electrolytic cell 1 to allow the precursor solution to infiltrate the surface of the electrode substrate.

[0020] The present invention also provides a method for preparing an alkaline electrolytic cell electrode, which is applied to the above-mentioned system and any preferred embodiment thereof, comprising:

[0021] Assembling the pretreated electrode substrate into the electrolytic cell 1;

[0022] A pre-configured precursor solution is input into the electrolytic cell 1 through a circulation pump 2, so that the precursor solution infiltrates the electrode substrate and circulates between the electrolytic cell 1, the anode-side gas-liquid separator 4, and the cathode-side gas-liquid separator 5;

[0023] The anode side gas flow regulator 6 and the cathode side gas flow regulator 7 are used to respectively introduce gas into the anode side gas-liquid separator 4 and the cathode side gas-liquid separator 5 to adjust the gas environment and pressure of the precursor solution;

[0024] After the precursor solution circulates for a preset time, the precursor solution is discharged and the electrode substrate is cleaned to obtain an electrode.

[0025] Compared with the prior art, the present invention has at least the following advantages:

[0026] By adopting the solution provided by the embodiment of the present invention, electrodes are prepared based on the electrolyzer, gas-liquid separator, circulation pump and other equipment of the alkaline electrolysis hydrogen production system. The size of the electrode can be adapted to the size of the cathode and anode in the electrolyzer, and full-size industrial anodes and cathodes can be prepared simultaneously, which significantly reduces the production cost of the electrode; multiple electrode substrates can be inserted into the electrolyzer at one time, so that multiple full-size industrial alkaline electrodes can be prepared at one time, which is suitable for the mass production of electrodes required for alkaline electrolysis hydrogen production equipment; moreover, the raw material cost is low, the precursor is recyclable, and the consistency between electrode preparation batches is good. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 This is a schematic structural diagram of an alkaline electrolytic cell electrode preparation system provided in an embodiment of the present invention.

[0028] Figure 2 A schematic flow chart of a method for preparing an alkaline electrolytic cell electrode provided in an embodiment of the present invention.

[0029] Figure 3 A schematic flow chart of a method for preparing an alkaline electrolytic cell electrode according to another embodiment of the present invention.

[0030] Figure 4 for Figure 3 Microscope image of the anode-side NiFe electrode prepared by the method shown.

[0031] Figure 5 A schematic diagram of polarization curves of a conventional Ni optical mesh anode, a conventional NiAl electrode, and an electrode prepared in accordance with an embodiment of the present invention is shown using a Chenhua CHI660E electrochemical workstation for comparative testing. DETAILED DESCRIPTION

[0032] In order to enable those skilled in the art to better understand the solutions of the present invention, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the embodiments described are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts should fall within the scope of protection of the present invention.

[0033] It should be noted that the terms "first," "second," and the like in the specification and claims of the present invention and the accompanying drawings are used to distinguish similar objects and are not necessarily used to describe a particular order or precedence. It should be understood that the terms used in this manner are interchangeable where appropriate to facilitate understanding of the embodiments of the present invention described herein. In addition, the terms "including," "comprising," and "having," as well as any variations thereof, are intended to cover non-exclusive inclusions. For example, a product or device comprising a series of elements is not necessarily limited to those elements explicitly listed, but may include other elements not explicitly listed or inherent to the product or device.

[0034] In the present invention, terms such as "upper," "lower," "left," "right," "front," "back," "top," "bottom," "inner," "outer," "center," "vertical," "horizontal," "transverse," and "longitudinal" indicate positions or locations based on the positions or locations shown in the accompanying drawings. These terms are primarily intended to better describe the present invention and its embodiments and are not intended to limit the devices, elements, or components indicated to having a specific orientation, or to being constructed or operated in a specific orientation.

[0035] Furthermore, some of the above terms may be used to express other meanings besides indicating a position or location. For example, the term "on" may also be used to indicate a dependency or connection in certain circumstances. Those skilled in the art will understand the specific meanings of these terms in the present invention based on the specific circumstances.

[0036] Furthermore, the terms "installed," "disposed," "provided with," "connected," "connected," and "socketed" should be interpreted broadly. For example, they can refer to fixed connections, removable connections, or integral structures; mechanical connections or electrical connections; direct connections or indirect connections through an intermediary; or internal communication between two devices, elements, or components. Those skilled in the art will understand the specific meanings of these terms in the present invention based on specific circumstances.

[0037] It should be noted that, in the absence of conflict, the embodiments and features of the embodiments of the present invention can be combined with each other. The present invention will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0038] Example 1

[0039] The embodiment of the present invention provides an alkaline electrolytic cell electrode preparation system. Figure 1 The structural diagram of the alkaline electrolytic cell electrode preparation system is shown in FIG. Figure 1 As shown, the system includes an electrolytic cell 1, a circulation pump 2, a precursor flow regulator 3, an anode side gas-liquid separator 4, a cathode side gas-liquid separator 5, an anode side gas flow regulator 6, and a cathode side gas flow regulator 7, wherein

[0040] Electrolytic cell 1, used for installing pre-treated electrode substrates at the anode position and cathode position respectively;

[0041] The inlet of the electrolytic cell 1 is connected to the circulation pump 2, which is connected to the precursor flow regulator 3, the anode-side gas-liquid separator 4, and the cathode-side gas-liquid separator 5, and receives the pre-configured precursor solution input through the precursor flow regulator 3, and the circulating precursor solution output from the anode-side gas-liquid separator 4 and the cathode-side gas-liquid separator 5;

[0042] The anode side outlet of the electrolytic cell 1 is connected to the upper part of the anode side gas-liquid separator 4, the cathode side outlet is connected to the upper part of the cathode side gas-liquid separator 5, and the bottom outlets of the anode side gas-liquid separator 4 and the cathode side gas-liquid separator 5 are respectively connected to the circulation pump 2;

[0043] The anode side gas-liquid separator 4 is connected to the anode side gas flow regulator 6, and the cathode side gas-liquid separator 5 is connected to the cathode side gas flow regulator 7. The anode side gas flow regulator 6 and the cathode side gas flow regulator 7 are used to introduce gas into the anode side gas-liquid separator 4 and the cathode side gas-liquid separator 5, respectively, to adjust the gas environment and pressure of the precursor solution.

[0044] In a preferred embodiment, the system may further include an anode side pressure regulator 8 and a cathode side pressure regulator 9;

[0045] The anode side pressure regulator 8 is connected to the anode side gas-liquid separator 4 and is used to adjust the pressure in the anode side gas-liquid separator 4;

[0046] The cathode side pressure regulator 9 is connected to the cathode side gas-liquid separator 5 and is used to regulate the pressure in the cathode side gas-liquid separator 5 .

[0047] The anode side gas flow regulator 6 and the cathode side gas flow regulator 7 can adjust the gas flow, thereby adjusting the gas pressure change rate of the precursor solution, etc. The gas pressure of the precursor solution can be further adjusted through the anode side pressure regulator 8 and the cathode side pressure regulator 9.

[0048] In one embodiment, the precursor flow regulator 3 , the anode-side gas flow regulator 6 , and the cathode-side gas flow regulator 7 are all adjustable valves.

[0049] In a preferred embodiment, the system may further include a heating system for heating the precursor solution in the anode-side gas-liquid separator 4 and the cathode-side gas-liquid separator 5 to maintain the temperature of the precursor solution within a preset range.

[0050] The heating system includes a circulating water system. Figure 1 As shown, the circulating water system passes through the anode side gas-liquid separator 4 and the cathode side gas-liquid separator 5, thereby heating the precursor solution in the anode side gas-liquid separator 4 and the cathode side gas-liquid separator 5 to keep it within a suitable temperature range.

[0051] The precursor solution may include a metal salt solution, or may include a metal salt solution and an alcohol solution or an H2O2 solution.

[0052] In a preferred embodiment, a distance is left between the electrode substrate and the diaphragm in the electrolytic cell 1 to allow the precursor solution to infiltrate the surface of the electrode substrate.

[0053] The anode-side gas flow regulator 6 and the cathode-side gas flow regulator 7 are respectively used to introduce oxygen, nitrogen, and / or compressed air into the anode-side gas-liquid separator 4 and the cathode-side gas-liquid separator 5. These introduced gases can adjust the gas environment of the electrode reaction and help promote the electrode reaction.

[0054] The precursor flow regulator 3 is further configured to drain the precursor solution after a preset reaction time and rinse with clean water. The preset reaction time is an empirical value. After this reaction time, an electrode layer has formed on the electrode substrate within the electrolytic cell. At this point, the precursor solution is drained and rinsed with clean water. Deionized water can be used for rinsing. After purging, an inert gas can be introduced. After purging, a modifying solvent can be introduced to modify the electrode surface to further enhance electrode performance.

[0055] In this system, the specific process for circulating the precursor solution (alkaline solution) is as follows: the precursor solution first flows through the precursor flow control valve 3 and is then fed into the electrolytic cell 1 by the circulation pump 2. The precursor solution then flows through the electrolytic cell 1 and exits from the anode and cathode sides, respectively. The precursor solution exiting the anode flows into the top of the anode-side gas-liquid separator 4; the precursor solution exiting the cathode flows into the top of the cathode-side gas-liquid separator 5. The precursor solutions in the anode-side gas-liquid separator 4 and the cathode-side gas-liquid separator 5 converge at the bottom of the gas-liquid separators and flow into the electrolytic cell through the circulation pump 2. During electrode preparation, an external gas source can be introduced into the gas-liquid separators 4 and 5 via the gas flow control valves 6 and 7 on the anode and cathode sides, respectively. During the electrode preparation process, preparation can also be achieved under a certain pressure. The pressures of the anode-side gas-liquid separator 4 and the cathode-side gas-liquid separator 5 are controlled by the oxygen-side pressure regulating valve 8 and the cathode-side pressure regulating valve 9, respectively.

[0056] To ensure that the precursor can fully infiltrate the electrode substrate in the electrolytic cell, connecting pipes are installed at the bottom of the gas-liquid separators on the anode and cathode sides to achieve equal pressure between the anode and cathode electrodes in the electrolytic cell. In addition, during the electrode preparation stage, the precursor solution in gas-liquid separators 4 and 5 can be heated by circulating circulating water at a certain temperature, thereby ensuring the continuous stability of the precursor temperature during electrode preparation.

[0057] By adopting the solution provided by the embodiment of the present invention, electrodes are prepared based on the electrolyzer, gas-liquid separator, circulation pump and other equipment of the alkaline electrolysis hydrogen production system. The size of the electrode can be adapted to the size of the cathode and anode in the electrolyzer, and full-size industrial anodes and cathodes can be prepared simultaneously, which significantly reduces the production cost of the electrode; multiple electrode substrates can be inserted into the electrolyzer at one time, so that multiple full-size industrial alkaline electrodes can be prepared at one time, which is suitable for the mass production of electrodes required for alkaline electrolysis hydrogen production equipment; moreover, the raw material cost is low, the precursor is recyclable, and the consistency between electrode preparation batches is good.

[0058] Example 2

[0059] Based on the same technical concept as that of the above-mentioned embodiment 1, the embodiment of the present invention provides a method for preparing an alkaline electrolytic cell electrode, which is applied to the electrode preparation system described in embodiment 1 and any embodiment thereof. Figure 2 A flow chart of the method is shown in FIG. Figure 2 As shown, the method includes:

[0060] Step 201 : Assemble the pretreated electrode substrate into the electrolytic cell 1 .

[0061] The pretreatment of the electrode substrate is used to remove dirt, oil stains, etc. on the surface of the electrode substrate to achieve a clean surface. The electrode substrate can be immersed in an acidic environment of a specific concentration and temperature for a certain period of time to remove oil stains on the electrode surface. The cleaned substrate can then be further treated by spray coating, electrodeposition, heat treatment, nitriding, etc.

[0062] After assembling the electrode substrate into the electrolytic cell 1, the electrode substrate and the diaphragm can be fastened together. Preferably, a certain distance should be left between the electrode substrate and the diaphragm to ensure that the subsequent precursor can fully infiltrate the electrode surface. The assembled electrolytic cell can then be maintained at a pressure of 0.1 MPa to 3.6 MPa for 0 to 48 hours. After the cell passes the leak test, proceed to the subsequent steps.

[0063] For example, the metal substrate can be made of one or more combinations of materials, such as metal mesh, metal fiber felt, and metal foam. Materials include nickel, nickel-iron alloy, stainless steel, and nickel-aluminum alloy. Treatment options include sandblasting or non-sandblasting. The metal substrate is immersed in an oxalic acid solution with a certain mass fraction, controlled at a temperature between 0 and 100°C, for 5 to 120 minutes. Subsequently, it is repeatedly rinsed with deionized water and ethanol to remove the oxide layer and oil stains on the electrode surface and increase its surface roughness. Further modification can be performed through methods such as spraying metal powder, electrodeposition, and heat treatment. After the above treatments, a pretreated electrode substrate is obtained.

[0064] In step 202 , a pre-configured precursor solution is input into the electrolytic cell 1 through the circulation pump 2 , so that the precursor solution infiltrates the electrode substrate and circulates between the electrolytic cell 1 , the anode-side gas-liquid separator 4 , and the cathode-side gas-liquid separator 5 .

[0065] The anode and cathode outlets of the electrolytic cell 1 are connected to the upper parts of the gas-liquid separators 4 and 5 respectively, and the pressure in the electrolytic cell is regulated by the gas-liquid separators 4 and 5. The liquid inlet of the electrolytic cell 1 is connected to the outlet of the circulation pump 2.

[0066] The metal salt is dissolved in water and thoroughly mixed to form a uniform metal salt solution, i.e., the precursor solution. The metal salt solution is then fed into the electrolytic cell 1 through the precursor flow regulator 3 and the circulation pump 2. The circulation pump 2 circulates the precursor solution between the electrolytic cell 1, the anode-side gas-liquid separator 4, and the cathode-side gas-liquid separator 5. During the preparation process, a certain concentration of alcohol solution or H2O2 solution can be added to the precursor as a catalyst to promote the electrode preparation reaction.

[0067] As an example, a metal salt of a specific concentration can be dissolved in deionized water, thoroughly mixed and stirred to prepare a metal salt solution with a concentration of 10 to 10,000 mmol / L, and a certain volume and concentration of H2O2 or an alcohol solution such as ethanol, isopropanol, isobutanol, or n-butanol can be added. The metal salt includes one or more of nickel nitrate, nickel chloride, nickel sulfate, ferric nitrate, ferrous nitrate, ferrous sulfate, ferric sulfate, ferric chloride, ferrous chloride, cobalt nitrate, cobalt sulfate, cobalt chloride, molybdenum chloride, ammonium molybdate, and sodium molybdate. The precursor solution is obtained through this preparation method and then input into the electrolytic cell for circulation.

[0068] In step 203 , gas is introduced into the anode side gas-liquid separator 4 and the cathode side gas-liquid separator 5 through the anode side gas flow regulator 6 and the cathode side gas flow regulator 7 respectively to adjust the gas environment and pressure of the precursor solution.

[0069] During the electrode preparation process, the precursor solution can be heated by a heater to maintain a suitable reaction temperature. For example, a circulating water heat exchanger can be used to heat the precursor solution, while a circulating pump can be used to circulate the precursor solution in the electrolytic cell.

[0070] Among them, external gas sources such as oxygen, nitrogen, and compressed air can also be introduced into the cathode and anode sides, and the gas pressure can be adjusted to promote electrode preparation through the gas environment and pressure.

[0071] In one example, the gas flow rate can be controlled by gas flow control valves 6 and 7, and the pressure range of the precursor solution can be adjusted to 0-1.6 MPa via oxygen side pressure control valve 8 and cathode side pressure control valve 9. During the preparation process, the precursor solution is heated by circulating water, and the temperature range of the precursor solution is controlled to be 0-90°C.

[0072] Step 204 : After the precursor solution circulates for a preset time, the precursor solution is discharged and the electrode substrate is cleaned to obtain an electrode.

[0073] When the precursor cycle reaches the preset time and the precursor solution is drained, clean water is immediately introduced to circulate and rinse the electrode until the electrode surface is clean and free of residue. The clean water is then drained and a gas at a certain temperature is introduced for a second cleaning and drying. After the electrode preparation is completed, the modification solution can be introduced to modify the electrode.

[0074] Among them, the circulation time of the precursor solution is, for example, 0.1-48h. During the circulation process of the precursor solution, the precursor ion concentration can be detected at regular intervals. If the concentration value is lower than the threshold, the precursor solution is replenished. Otherwise, the precursor flow regulator 3 can be closed and only the precursor solution that has been input into the system is circulated.

[0075] The modification treatment of the electrode may include, for example:

[0076] A modification solution is prepared and introduced into the electrolytic cell 1 using a circulation pump 2 to modify the electrode. The modification solvent concentration is 0 to 10,000 mmol / L, the immersion temperature is 0 to 90°C, and the immersion time is 0 to 48 hours. After the modification is completed, the electrode is rinsed again with clean water and then dried with compressed air at 0 to 90°C. The modification solvent includes one or more of sodium phosphite, potassium phosphite, sodium hypophosphite, potassium hypophosphite, sodium borohydride, potassium borohydride, boric acid, phosphoric acid, silver nitrate, and the like.

[0077] The modified solution can also be injected into the electrode preparation system through the circulation pump 2, and one or more gases such as compressed air, oxygen and nitrogen are introduced at the same time. The pressure range of the modified solution is adjusted to 0-1.6Mpa using the gas flow regulators 6 and 7. During the preparation process, the modified solution is heated by an external heat source (such as circulating water) at a heating temperature of 0-100°C. The modified solution circulation time is 0.1-48h. During the modified solution circulation process, the concentration of the main active ions in the solution is detected and replenished at regular intervals. After the modification treatment is completed, the modified solution is discharged and then rinsed with clean water, and then purged again with a certain temperature gas, and finally the modified electrode is obtained.

[0078] In one embodiment, the pretreated electrode substrate can be installed and secured as required at the anode and cathode positions of the electrolytic cell, which is then connected to the system. A proportionally configured precursor solution is added to the gas-liquid separator and the cycle is initiated. During the alkali solution circulation process, oxygen / compressed air is continuously introduced into the gas-liquid separator, and the temperature and pressure of the precursor are adjusted using a pressure regulating valve and an external heat source. After the electrode is prepared, the precursor flow regulating valve is opened to drain the precursor solution and store it, followed by rinsing with clean water. After cleaning, nitrogen is introduced for further cleaning.

[0079] It should be noted that the above steps provided in the embodiment of the present invention are only examples, and the order of the steps can be changed if they are not contradictory to each other.

[0080] By adopting the solution provided by the embodiment of the present invention, electrodes are prepared based on the electrolyzer, gas-liquid separator, circulation pump and other equipment of the alkaline electrolysis hydrogen production system. The size of the electrode can be adapted to the size of the cathode and anode in the electrolyzer, and full-size industrial anodes and cathodes can be prepared simultaneously, which significantly reduces the production cost of the electrode; multiple electrode substrates can be inserted into the electrolyzer at one time, so that multiple full-size industrial alkaline electrodes can be prepared at one time, which is suitable for the mass production of electrodes required for alkaline electrolysis hydrogen production equipment; moreover, the raw material cost is low, the precursor is recyclable, and the consistency between electrode preparation batches is good.

[0081] Example 3

[0082] Based on the same technical concept as the above-mentioned embodiments 1 and 2, the embodiment of the present invention provides a method for preparing an alkaline electrolytic cell electrode, which is applied to the electrode preparation system described in embodiment 1 and any embodiment thereof. Figure 3 A flow chart of the method is shown in FIG. Figure 3 As shown, the method includes:

[0083] Step 301 , cutting 6 pieces of nickel metal mesh with a diameter of 260 mm, immersing the nickel metal mesh in a 5 wt % oxalic acid solution at 90° C. for 10 to 60 minutes, taking it out and rinsing it with clean water to serve as an electrode substrate.

[0084] Step 302: Place the cleaned electrode substrate into an industrial alkaline electrolytic cell, with the cleaned electrode substrates on the anode and cathode sides of the electrolytic cell, respectively.

[0085] The electrolytic cell can include multiple chambers, each of which is where the electrolytic reaction occurs. In this embodiment, the electrolytic cell has three chambers, and the diaphragm is a polyphenylene sulfide (PPS) diaphragm. The installed electrolytic cell was subjected to a pressure test at 3 MPa. The installed electrolytic cell was then connected to the electrode preparation system described above.

[0086] Step 303: accurately weigh a certain amount of nickel sulfate hexahydrate (NiSO4·6H2O) and a certain amount of ferrous sulfate heptahydrate (FeSO4·7H2O), dissolve them in 30 L of deionized water, and stir at 500 rpm to prepare a solution containing 0.01-0.5 mol / L Ni 2+ and 0.01~0.5mol / L Fe 2+ concentration of metal salt precursor solution.

[0087] In step 304, the prepared precursor solution is injected into the electrode preparation system and the circulation system is started. During the circulation, the precursor solution is heated to 20-80°C by an external heat source; compressed air is introduced and the electrode preparation pressure is adjusted to 0.1-1.0 MPa using a pressure regulating valve.

[0088] Among them, temperature sensors and pressure sensors can be installed and feedback information can be provided, and the controller automatically adjusts the temperature and pressure according to the feedback information.

[0089] During the electrode preparation process, the precursor solution circulation time is preferably 24 hours, and the uniform formation of NiFe-LDH is promoted based on the following reaction mechanism: through the uniform contact and disturbance of oxygen and the catalytic material, the oxidation of ferrous ions to ferric ions is promoted; the ferric ions then oxidize the nickel metal to divalent nickel ions, while the ferric ions are reduced to divalent ferrous ions; finally, the NiFe-LDH structure is generated under the co-reaction of divalent nickel ions, divalent ferrous ions, ferric ions, hydroxide, and oxygen. During the preparation process, the nucleation process is promoted by the disturbance of oxygen bubbles, further accelerating the formation of the catalyst.

[0090] During the preparation process, a certain concentration of external compounds may be added to promote the preparation of the electrode material, for example, H2O2 or alcohol solutions such as ethanol, isopropanol, isobutanol, and n-butanol may be added.

[0091] Step 305: After the cycle is completed, the electrolytic cell is removed from the system, the electrodes are taken out and thoroughly rinsed with deionized water to remove any residual electrolyte components on the electrodes, and finally a NiFe-LDH electrode material with optimized performance is prepared.

[0092] Figure 4 A microscope image of the anode-side NiFe electrode prepared using the method provided in an embodiment of the present invention is shown. It can be observed from the image that the catalytic material has a lamellar structure. Figure 5 A schematic diagram of polarization curves comparing a conventional Ni light-mesh anode, a conventional NiAl electrode, and an electrode prepared using an embodiment of the present invention is shown using a Chenhua CHI660E electrochemical workstation. The horizontal axis represents the voltage relative to a hydrogen standard electrode, and the vertical axis represents the current density. The results show that the electrode prepared using the solution of the embodiment of the present invention significantly outperforms the NiAl anode and the Ni light-mesh electrode.

[0093] By adopting the solution provided by the embodiment of the present invention, electrodes are prepared based on the electrolyzer, gas-liquid separator and circulation pump of the alkaline electrolysis hydrogen production system. The size of the electrode can be adapted to the size of the cathode and anode in the electrolyzer, and the simultaneous preparation of full-size industrial anodes and cathodes can be achieved, significantly reducing the production cost of the electrode; multiple electrode substrates can be inserted into the electrolyzer at one time, so that multiple full-size industrial alkaline electrodes can be prepared at one time, which is suitable for batch production of electrodes required for alkaline electrolysis hydrogen production equipment; moreover, the cost of raw materials is low, the precursor can be recycled, and the consistency between electrode preparation batches is good. Moreover, using the electrode preparation solution provided by the embodiment of the present invention, the electrolyzer electrodes can also be reactivated and repaired to ensure the stability of the electrolysis hydrogen production equipment during long-term operation. The metal salt solution used in the present invention can be reused repeatedly, reducing the cost of industrial electrode preparation.

[0094] Finally, it should be noted that the above embodiments are intended only to illustrate the technical solutions of the present invention and are not intended to limit them. Those skilled in the art will appreciate that the technical solutions described in the aforementioned embodiments may be modified, or some of the technical features thereof may be replaced with equivalents; such modifications or replacements do not deviate from the spirit and scope of the technical solutions of the various embodiments of the present invention.

Claims

1. An alkaline electrolytic cell electrode preparation system, characterized in that: The invention comprises an electrolytic cell (1), a circulation pump (2), a precursor flow regulator (3), an anode-side gas-liquid separator (4), a cathode-side gas-liquid separator (5), an anode-side gas flow regulator (6), and a cathode-side gas flow regulator (7), wherein An electrolytic cell (1) is used to install pretreated electrode substrates at the anode position and the cathode position respectively; The inlet of the electrolytic cell (1) is connected to a circulation pump (2), which is connected to a precursor flow regulator (3), an anode-side gas-liquid separator (4), and a cathode-side gas-liquid separator (5), and receives a pre-configured precursor solution input through the precursor flow regulator (3), and a circulating precursor solution output from the anode-side gas-liquid separator (4) and the cathode-side gas-liquid separator (5); The anode side outlet of the electrolytic cell (1) is connected to the upper part of the anode side gas-liquid separator (4), the cathode side outlet is connected to the upper part of the cathode side gas-liquid separator (5), and the bottom outlets of the anode side gas-liquid separator (4) and the cathode side gas-liquid separator (5) are respectively connected to the circulation pump (2); The anode side gas-liquid separator (4) is connected to the anode side gas flow regulator (6), and the cathode side gas-liquid separator (5) is connected to the cathode side gas flow regulator (7). The anode side gas flow regulator (6) and the cathode side gas flow regulator (7) are used to respectively introduce gas into the anode side gas-liquid separator (4) and the cathode side gas-liquid separator (5) to adjust the gas environment and pressure of the precursor solution.

2. The alkaline electrolytic cell electrode preparation system according to claim 1, characterized in that: Also includes an anode side pressure regulator (8) and a cathode side pressure regulator (9); The anode side pressure regulator (8) is connected to the anode side gas-liquid separator (4) and is used to regulate the pressure in the anode side gas-liquid separator (4); The cathode side pressure regulator (9) is connected to the cathode side gas-liquid separator (5) and is used to regulate the pressure in the cathode side gas-liquid separator (5).

3. The alkaline electrolytic cell electrode preparation system according to claim 1, characterized in that: The invention also includes a heating system for heating the precursor solution in the anode side gas-liquid separator (4) and the cathode side gas-liquid separator (5) so as to maintain the temperature of the precursor solution within a preset range.

4. The alkaline electrolytic cell electrode preparation system according to claim 3, characterized in that: The heating system includes a circulating water system.

5. The alkaline electrolytic cell electrode preparation system according to any one of claims 1 to 4, characterized in that: The precursor solution includes a metal salt solution.

6. The alkaline electrolytic cell electrode preparation system according to claim 5, characterized in that: The precursor solution includes an alcohol solution or a H2O2 solution.

7. The alkaline electrolytic cell electrode preparation system according to any one of claims 1 to 4, characterized in that: The anode side gas flow regulator (6) and the cathode side gas flow regulator (7) are used to respectively introduce oxygen, nitrogen, and / or compressed air into the anode side gas-liquid separator (4) and the cathode side gas-liquid separator (5).

8. The alkaline electrolytic cell electrode preparation system according to any one of claims 1 to 4, characterized in that: The precursor flow regulator (3) is also used to: after a preset reaction time, drain the precursor solution and introduce clean water for cleaning.

9. The alkaline electrolytic cell electrode preparation system according to any one of claims 1 to 4, characterized in that: A distance is left between the electrode substrate and the diaphragm in the electrolytic cell (1) so as to allow the precursor solution to infiltrate the surface of the electrode substrate.

10. A method for preparing an alkaline electrolytic cell electrode, applied to a system according to any one of claims 1 to 9, characterized in that: include: Assembling the pretreated electrode substrate into an electrolytic cell (1); A pre-configured precursor solution is input into the electrolytic cell (1) via a circulation pump (2), so that the precursor solution infiltrates the electrode substrate, and the precursor solution is circulated between the electrolytic cell (1), the anode-side gas-liquid separator (4), and the cathode-side gas-liquid separator (5); The anode-side gas flow regulator (6) and the cathode-side gas flow regulator (7) are used to respectively introduce gas into the anode-side gas-liquid separator (4) and the cathode-side gas-liquid separator (5) to adjust the gas environment and pressure of the precursor solution; After the precursor solution circulates for a preset time, the precursor solution is discharged and the electrode substrate is cleaned to obtain an electrode.

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