Bimetal loaded cathode, preparation method thereof, electrolytic descaling device and electrolytic descaling method

Abstract

The invention provides a bimetallic load cathode and a preparation method thereof, and an electrolytic descaling device and method, the cathode is prepared by dipping a metal electrode substrate in a mixed solution containing a Ru source and a metal A source, the metal A is selected from any one of Ni, Co and Ce, the molar ratio of the Ru source to the metal A source is (1-100): 1, the molar weight of the Ru source is calculated by the molar weight of Ru, and the molar weight of the metal A is calculated by the molar weight of Ru. The molar weight of the A metal source is calculated according to the molar weight of A metal, and the metal electrode substrate is carbon steel or stainless steel. By means of the double-metal synergistic effect, the cathode hydrogen evolution potential is reduced, the electrolytic descaling efficiency is improved, especially the descaling efficiency under the low electrolytic current density is improved, it is guaranteed that the cathode material catalyst layer is evenly distributed and has high binding force and corrosion resistance, and the industrial application requirement is further met.

Description

Technical Field

[0001] The present invention relates to the technical field of electrolytic descaling, and in particular to a high hydrogen evolution activity bimetallic loaded carbon steel or stainless steel cathode used in an electrolytic descaling device, a preparation method thereof, and a corresponding electrolytic descaling method. Background Art

[0002] Electrolytic descaling technology removes scale by causing cations such as calcium and magnesium in water to migrate to the cathode under the action of a DC electric field, and then combine with hydroxide to form a precipitate in the alkaline microenvironment of the cathode interface, thereby achieving environmental friendliness and easy operation.

[0003] The cathode is the core component of the electrolytic descaling device, and its hydrogen evolution performance directly affects the descaling efficiency and energy consumption.

[0004] Carbon steel is currently the most commonly used cathode material in industrial electrolytic descaling due to its advantages such as high mechanical strength and low cost. However, carbon steel has low electrolytic descaling efficiency at low current densities. Therefore, industrial applications often rely on high electrolysis currents, making it difficult to reduce energy consumption. Summary of the Invention

[0005] (1) Purpose of the invention

[0006] The purpose of the present invention is to provide a bimetallic-loaded metal cathode and its preparation method, an electrolytic descaling device and method, wherein bimetallic is loaded on the surface of a carbon steel or stainless steel electrode substrate by an impregnation method, and the hydrogen evolution potential of the cathode is reduced through the bimetallic synergistic effect, thereby improving the electrolytic descaling efficiency, especially the descaling efficiency under low electrolysis current density, and ensuring that the catalytic layer of the cathode material is evenly distributed and has strong bonding strength and corrosion resistance, further meeting the needs of industrial applications.

[0007] (2) Technical solution

[0008] To solve the above problems, the first aspect of the present invention provides a bimetallic loaded cathode, which is prepared by immersing a metal electrode substrate in a mixed solution containing a Ru source and an A metal source, wherein the A metal is selected from any one of Ni, Co, and Ce, and the molar ratio of the Ru source to the A metal source is 1-100:1. The molar amount of the Ru source is calculated based on the molar amount of Ru, and the molar amount of the A metal source is calculated based on the molar amount of the A metal. The metal electrode substrate is carbon steel or stainless steel.

[0009] In the embodiment of the present invention, the metal electrode substrate is a sheet of carbon steel or a sheet of stainless steel.

[0010] By impregnating the metal electrode substrate with bimetallic materials, the cathode hydrogen evolution potential is reduced through the bimetallic synergistic effect, which not only improves the electrolytic descaling efficiency but also ensures that the cathode material catalytic layer is evenly distributed and has strong bonding strength and corrosion resistance, thus better meeting the needs of industrial applications.

[0011] In a preferred embodiment, the A metal is Ni or Ce, and the molar ratio of the Ru source to the A metal source is 5-50:1; or the A metal is Co, and the molar ratio of the Ru source to the A metal source is 90-100:1.

[0012] While improving the hydrogen evolution capacity, it can ensure that the bimetallic layer loaded on the cathode surface is evenly and densely distributed.

[0013] In a more preferred embodiment, the A metal is Ce, and the molar ratio of the Ru source to the A metal source is 9-11:1.

[0014] When Ru and Ce are mixed in the above molar ratio, the bimetallic loaded carbon steel cathode is -2 Under the current density, the hydrogen evolution potential can be reduced to -1.28V, and the catalytic layer on the surface of the bimetallic-loaded carbon steel cathode is uniform, dense and has good bonding strength;

[0015] At the same time, the bimetallic loaded carbon steel cathode is 0.05-0.1A·dm -2 Compared with carbon steel electrodes, the hardness removal rate is increased by more than 27% and the alkalinity removal rate is increased by more than 30% under the current density, which can achieve the same performance as carbon steel electrodes at the current density commonly used in industry (0.2A·dm -2 ) has a comparable scale removal efficiency under long-term continuous and stable operation of the electrolytic descaling system. Low current density operation can not only effectively reduce energy consumption and lower operating costs, but also reduce the loss and degradation of the electrode under high current, thus forming a good protection for the life of the electrode, which is conducive to a more economical and long-term operation of the system.

[0016] Specifically, the Ru source is selected from organic solvent soluble salts of Ru, preferably ruthenium trichloride trihydrate; the A metal source is selected from organic solvent soluble salts of A metal, preferably nickel chloride hexahydrate, cobalt chloride hexahydrate, cerium chloride heptahydrate.

[0017] In an optional embodiment, the organic solvent is a mixed solution of ethanol and isopropanol, wherein the volume ratio of ethanol to isopropanol is 1:15-25, the molar content of the Ru source in the mixed solution is 0.01-0.02 mol / L, and the molar concentration of the A metal source is 0.00015-0.015 mol / L.

[0018] The metal electrode substrate is prepared by immersing it in a mixed solution containing a Ru source and an A metal source. The specific preparation method is consistent with the preparation method of the second aspect of the present invention. For specific details, please refer to the description of the preparation method below.

[0019] A second aspect of the present invention provides a method for preparing a bimetallic loaded cathode, which is used to prepare the bimetallic loaded cathode. The specific method includes:

[0020] Step 1: Pre-treating the metal electrode substrate;

[0021] Step 2: Immerse the pretreated metal electrode substrate in a mixed solution containing a Ru source and a metal source for reaction, and dry to obtain a bimetallic loaded carbon steel cathode.

[0022] The metal electrode substrate described in step 1 of the present invention is pretreated, specifically including: polishing, degreasing, ultrasonic cleaning, etching and drying.

[0023] Specifically, the polishing conditions include: using 600-1200 mesh sandpaper to polish along the same direction of the surface of the metal electrode substrate to remove surface impurities and oxide layers to make the surface smooth and uniform;

[0024] Specifically, a surfactant such as laundry detergent is used to scrub and remove oil from the polished metal electrode substrate;

[0025] The ultrasonic cleaning specifically includes: using ethanol as a cleaning agent and a cleaning time of 20-40 seconds;

[0026] The specific conditions of the etching include: the etching solution is a mixture of concentrated sulfuric acid, concentrated nitric acid and water, wherein the concentrated sulfuric acid is 5-10 mL / L and the concentrated nitric acid is 3-10 mL / L, and the etching time is 30-60 s.

[0027] Through the pre-treatment process of sandpaper polishing - degreasing - ultrasonic cleaning - etching, the surface of the carbon steel substrate can be kept clean and have a certain roughness, which is more conducive to the subsequent impregnation of elements.

[0028] Specifically, the reaction in step 2 includes:

[0029] The reaction temperature is 20-60°C, and the reaction time is 3-28h.

[0030] Specifically, the Ru source is selected from an organic solvent-soluble salt of Ru, preferably ruthenium trichloride trihydrate; the A metal source is selected from an organic solvent-soluble salt of Metal A, preferably nickel chloride hexahydrate, nickel nitrate hexahydrate, cobalt chloride hexahydrate, cobalt nitrate hexahydrate, cerium chloride heptahydrate, or cerium nitrate hexahydrate. In an optional embodiment, the organic solvent is a mixed solution of ethanol and isopropanol, wherein the volume ratio of ethanol to isopropanol is 1:15-25, and the molar content of the Ru source in the mixed solution is 0.01-0.02 mol / L. The molar concentration of the A metal source is 0.00015-0.015 mol / L.

[0031] After the reaction is completed, it can be dried naturally or dried in an oven at 50-200°C for 15-120 minutes.

[0032] In a specific embodiment of the present invention, a process for preparing a Ce-Ru dual-loaded carbon steel cathode with high hydrogen evolution activity for use in an electrolytic descaling device comprises the following steps:

[0033] S1. Pretreatment of the Metal Electrode Matrix: Polish the carbon steel sheet with sandpaper of varying grits until the surface is smooth. Then, ultrasonically clean the sheet in an ethanol solution to remove surface oil and impurities. Rinse the sheet with deionized water and dry it for later use. Etch the sheet in an etching solution, quickly rinse it with deionized water, and dry it for later use.

[0034] S2. Preparation of Ru-based bimetallic loaded component solution: fix the amount of ruthenium trichloride trihydrate (RuCl3·3H2O), weigh nickel chloride hexahydrate (NiCl2·6H2O), cobalt chloride hexahydrate (CoCl2·6H2O), cerium chloride heptahydrate (CeCl3·7H2O), and lanthanum chloride heptahydrate (LaCl3·7H2O) respectively, adjust the loading molar ratio of Ni / Co / Ce / La and Ru according to the proportion, first add ethanol to completely dissolve the Ni / Co / Ce / La salt, then weigh RuCl3·3H2O and mix and dissolve the above substances with isopropanol to prepare four bimetallic solutions of Ni-Ru, Co-Ru, Ce-Ru, and La-Ru, and fix the volume for use.

[0035] S3. Impregnation and drying of Ru-based bimetallic loaded carbon steel cathode: vertically immerse the pretreated carbon steel sheet in the above solution, maintain a constant temperature throughout the immersion process, take out the carbon steel sheet after immersion for a certain period of time and put it into an oven for drying. After a certain period of time, let the carbon steel sheet slowly cool down with the oven until it reaches room temperature to obtain a bimetallic loaded carbon steel cathode.

[0036] Furthermore, in step S1, the ultrasonic cleaning time is 2 minutes.

[0037] Furthermore, in step S1, the etching solution is composed of a sulfuric acid-nitric acid mixture, which contains 8.3 mL / L concentrated sulfuric acid and 5.5 mL / L concentrated nitric acid, and the etching time is 30 s.

[0038] Furthermore, in step S3, the immersion temperature is controlled at 20-60°C throughout the experiment, the immersion time is 3-48 hours, the drying temperature is naturally dried at 50-200°C, and the drying time is 15-120 minutes.

[0039] Furthermore, in step S2, the amount of ruthenium chloride trihydrate (RuCl3·3H2O) is 4 g / L, and the molar ratio of Ni / Co / Ce / La and Ru is adjusted to be 1:1 to 1:100.

[0040] Furthermore, in step S2, the amount of ethanol used to dissolve the Ni / Co / Ce / La salt is 5 mL.

[0041] The third aspect of the present invention provides an electrolytic descaling device, comprising an electrolyte, a DC power supply and a cathode connected to the DC power supply, wherein the electrolyte comprises water, and the cathode is any one of the above-mentioned bimetallic-loaded carbon steel cathode and the bimetallic-loaded carbon steel cathode prepared by the above-mentioned preparation method.

[0042] For a detailed description of the cathode, please refer to the description of the cathode and preparation method above, which will not be repeated here.

[0043] Specifically, the current density of the DC power supply is 0.025 to 0.2 A·dm -2 . Preferably 0.05~0.1A·dm -2 At this current density, the same current density as the blank carbon steel electrode can be achieved at the industrially commonly used current density (0.2A·dm -2 ) to achieve comparable scale removal efficiency under long-term, continuous, and stable electrolytic descaling systems, low current density operation can effectively reduce energy consumption and operating costs, while also alleviating electrode wear and degradation under high currents, effectively protecting electrode life and contributing to more economical and long-term system operation.

[0044] Specifically, the initial total hardness of the water is 300-500 mg / L (calculated as CaCO3). When the hardness of the water is within this range, the device is used at a current density of 0.025-0.2 A·dm -2 When the Ce-Ru double-loaded carbon steel cathode with a Ce to Ru molar ratio of 1:9-11 has a hardness removal rate of 14.8%-22.3% in about 1 hour, especially at a current density of 0.025A·dm -2 When the hardness is reduced by 1.5%, the hardness removal rate of Ce-Ru dual-loaded carbon steel cathode is increased by 78.3% compared with the blank carbon steel.

[0045] In a fourth aspect, the present invention provides an electrolytic descaling method, which is performed using any of the devices described above. For a description of the device, please refer to the above-mentioned device, which will not be repeated here.

[0046] Preferably, the method comprises:

[0047] A certain amount of water to be treated is pre-electrolyzed, wherein the current density of the pre-electrolyzed water is 0.025-0.2A·dm -2 , time is 10-30min;

[0048] Remove the water after pre-electrolytic descaling, add the water to be treated as electrolyte, and perform electrolytic descaling.

[0049] Pre-electrolysis can eliminate the interference of scale ions and activate the electrodes, so that the scale removal and hydrogen evolution reaction can be carried out synergistically and efficiently during the main electrolysis, and the scale removal efficiency of the electrode within 1 hour can be increased by more than 10%.

[0050] (3) Beneficial effects

[0051] The above technical solution of the present invention has the following beneficial technical effects:

[0052] The present invention loads bimetallic materials on the surface of a metal electrode substrate through an impregnation method. The bimetallic synergistic effect reduces the cathode hydrogen evolution potential, thereby improving the electrolytic descaling efficiency, especially the descaling efficiency at low current density, and ensuring that the cathode material catalytic layer is evenly distributed and has strong bonding strength and corrosion resistance, thus meeting the needs of industrial applications. BRIEF DESCRIPTION OF THE DRAWINGS

[0053] Figure 1 The hydrogen evolution effect diagram provided by Examples 1-4 of the present invention, wherein a is the cathode hydrogen evolution LSV curve, b is the cathode at 1 mA·cm -2 Hydrogen evolution potential diagram at current density;

[0054] Figure 2 The hydrogen evolution effect diagrams provided in Examples 5-8 of the present invention, wherein a is the cathode hydrogen evolution LSV curve, b is the cathode at 1 mA·cm -2 Hydrogen evolution potential diagram at current density;

[0055] Figure 3 The hydrogen evolution effect diagrams provided in Examples 9-12 of the present invention, wherein a is the cathode hydrogen evolution LSV curve, b is the cathode at 1 mA·cm -2 Hydrogen evolution potential diagram at current density;

[0056] Figure 4 Surface morphologies of cathodes provided in Examples 9-12 of the present invention, wherein a is Example 9, b is Example 10, c is Example 11, and d is Example 12;

[0057] Figure 5 The graph shows the change of open circuit potential of the cathode of blank carbon steel and Ce-Ru dual-loaded carbon steel provided in Example 10 over time. DETAILED DESCRIPTION

[0058] To make the objectives, technical solutions, and advantages of the present invention more clearly understood, the present invention will be further described in detail below in conjunction with specific embodiments and with reference to the accompanying drawings. It should be understood that these descriptions are merely exemplary and are not intended to limit the scope of the present invention. In addition, in the following description, descriptions of well-known structures and technologies are omitted to avoid unnecessary confusion of the concepts of the present invention.

[0059] The raw materials and reagents used in the embodiments of the present invention are all conventional commercially available products, among which:

[0060] The carbon steel electrode substrate used in each embodiment of the present invention is a Q235 carbon steel sheet of Model I purchased from Feiruida Machinery Equipment Business Department in Jinshan District, Shanghai;

[0061] The ruthenium-iridium-titanium mesh anode used was purchased from Suzhou Shuertai Industrial Technology Co., Ltd., with a model of 65 mm × 130 mm × 1 mm;

[0062] The Ru source used was ruthenium trichloride trihydrate purchased from Shanghai MacLean Biochemical Technology Co., Ltd. with a purity of 98%;

[0063] Nickel chloride hexahydrate, cobalt chloride hexahydrate, and cerium chloride heptahydrate in the metal source A were purchased from Shanghai MacLean Biochemical Technology Co., Ltd. with a purity of 99%;

[0064] The organic solvent isopropyl alcohol was purchased from Tianjin Fuyu Fine Chemical Co., Ltd. with a purity of 99.7%;

[0065] Anhydrous ethanol was purchased from Fuchen (Tianjin) Chemical Reagent Co., Ltd. with a purity of 95%;

[0066] The concentrated sulfuric acid and concentrated nitric acid used in the etching solution were purchased from Beijing Tongguang Fine Chemical Company, with mass fractions of 98% and 68%, respectively.

[0067] Example 1

[0068] A Ni-Ru dual-loaded carbon steel cathode, the specific preparation steps of which are as follows:

[0069] Step 1: Pretreatment of carbon steel electrode substrate

[0070] Use 600-grit and then 1200-grit sandpaper to polish the carbon steel sheet in the same direction until the surface is smooth and uniform, removing surface impurities and oxide layers. Use an appropriate amount of laundry detergent to scrub and degrease the carbon steel sheet, rinse with an appropriate amount of deionized water, and quickly blow dry with cold air. Then, ultrasonically clean the carbon steel sheet in anhydrous ethanol for 30 seconds, remove it, rinse it with deionized water, and quickly blow dry it for later use. Finally, etch it in an etching solution for 30 seconds, then immediately remove it, quickly rinse it with deionized water, and dry it for later use. The etching solution is composed of a mixture of concentrated sulfuric acid, concentrated nitric acid, and water, with 8.3 mL / L of concentrated sulfuric acid and 5.5 mL / L of concentrated nitric acid.

[0071] Step 2: Preparation of Ni-Ru dual loading solution

[0072] NiCl2·6H2O was used as the nickel source, and RuCl3·3H2O was used as the Ru source. The nickel source and Ru source were weighed in a ratio of 1:1 and placed in a beaker.

[0073] First, 5 ml of ethanol was used to dissolve the nickel source, and then 95 ml of isopropanol was slowly poured into it. The mixed solution was slowly stirred with a glass rod until the mixed solution was uniformly dissolved, thereby preparing a Ni-Ru dual-load solution with a Ru molar concentration of 0.015 mol / L.

[0074] Step 3: Vertically immerse the carbon steel sheet obtained by the pretreatment in the first step into the dual-load solution obtained in the second step, and maintain a constant temperature of 30°C throughout the immersion process. After immersion for 24 hours, take out the carbon steel sheet and put it into an oven at a temperature of 100°C for 30 minutes. After drying, let the carbon steel sheet cool with the oven to obtain a Ni-Ru dual-load carbon steel cathode.

[0075] Examples 2-4

[0076] A Ni-Ru dual-loaded carbon steel cathode is provided respectively, and the preparation method is basically the same as that of Example 1, except that: the molar ratio of Ni to Ru in the second step of Example 2 is 1:10, the molar ratio of Ni to Ru in the second step of Example 3 is 1:50, and the molar ratio of Ni to Ru in the second step of Example 4 is 1:100.

[0077] Example 5

[0078] A Co-Ru dual-loaded carbon steel cathode, the specific preparation steps of which are as follows:

[0079] The first step is the same as in Example 1;

[0080] Step 2: The same as Example 1, except that CoCl2·6H2O was used instead of the nickel source to obtain a Co-Ru dual-load solution with a molar ratio of Co to Ru of 1:1.

[0081] Third step: same as the example, to get Co-Ru double-loaded carbon steel cathode.

[0082] Examples 6-8

[0083] A Co-Ru double-loaded carbon steel cathode is provided, and the preparation method is basically the same as that of Example 5, except that in Example 6, the molar ratio of Co to Ru in the second step is 1:10, in Example 7, the molar ratio of Co to Ru in the second step is 1:50, and in Example 8, the molar ratio of Co to Ru in the second step is 1:100.

[0084] Example 9

[0085] A Ce-Ru double-loaded carbon steel cathode is provided, and the specific preparation steps are as follows:

[0086] First step: same as Example 1;

[0087] Second step: basically the same as Example 1, except that CeCl3·7H2O is used instead of the nickel source to prepare a Ce-Ru double-loaded solution with a molar ratio of Ce to Ru of 1:1.

[0088] Third step: same as Example 1, to get Ce-Ru double-loaded carbon steel cathode.

[0089] Examples 10-12

[0090] A Ce-Ru double-loaded carbon steel cathode is provided, and the preparation method is basically the same as that of Example 9, except that in Example 10, the molar ratio of Ce to Ru in the second step is 1:10, in Example 11, the molar ratio of Ce to Ru in the second step is 1:50, and in Example 12, the molar ratio of Ce to Ru in the second step is 1:100.

[0091] Comparative Example 1

[0092] The specific preparation steps of the single-loaded Ru carbon steel cathode are as follows:

[0093] First step: carbon steel substrate pretreatment

[0094] The carbon steel sheet is polished in the same direction with 600 mesh and 1200 mesh sandpaper until the surface is smooth and uniform, and the surface impurities and oxide layer are removed; the carbon steel sheet is washed with laundry detergent to remove oil, rinsed with deionized water, and quickly blown dry; then the carbon steel sheet is placed in anhydrous ethanol and ultrasonically cleaned for 30 seconds, then rinsed with deionized water and quickly blown dry; finally, the carbon steel sheet is etched in etching solution for 30 seconds, then immediately removed, rinsed with deionized water and dried for use. The composition of the etching solution is a mixture of concentrated sulfuric acid, concentrated nitric acid and water, containing 8.3 mL / L of concentrated sulfuric acid and 5.5 mL / L of concentrated nitric acid.

[0095] Step 2: Preparation of single loaded Ru solution

[0096] Weigh a certain amount of ruthenium chloride trihydrate (RuCl3·3H2O), place it in a beaker, and slowly pour an appropriate amount of isopropyl alcohol into it. Use a glass rod to slowly stir until the ruthenium chloride trihydrate is completely dissolved. Then, transfer the solution to a brown volumetric flask using the glass rod to drain. Continue to rinse the inner wall of the beaker repeatedly with isopropyl alcohol and transfer it to the volumetric flask. Dilute to the scale line to finally prepare a Ru solution with a concentration of 4 g / L.

[0097] Step 3: Impregnation and drying of single-loaded Ru carbon steel cathode

[0098] The pretreated carbon steel sheet was vertically immersed in the Ru-loaded solution, and the temperature was maintained at 30°C throughout the immersion process. After immersion for 24 hours, the carbon steel sheet was taken out and placed in an oven at 100°C for 30 minutes. After drying, the carbon steel sheet was allowed to cool in the oven to obtain a single-loaded Ru carbon steel cathode.

[0099] Comparative Example 2

[0100] The specific preparation steps of La-Ru dual-loaded carbon steel cathode are as follows:

[0101] Step 1: The carbon steel substrate pretreatment method is the same as in Example 1.

[0102] Step 2: Preparation of La-Ru dual loading solution

[0103] With a fixed amount of RuCl₃·3H₂O and LaCl₃·7H₂O as the La source, adjust the La-Ru loading molar ratio to 1:1. Calculate the required amount of LaCl₃·7H₂O according to the ratio. First, add a small amount of ethanol to completely dissolve the La salt. Then, weigh a fixed amount of RuCl₃·3H₂O and place it in a beaker. Slowly pour an appropriate amount of isopropanol into the mixture. Stir gently with a glass rod until the mixture is evenly dissolved. Then, drain the solution into a brown volumetric flask using a glass rod. Continue adding appropriate amounts of isopropanol to repeatedly rinse the inner wall of the beaker and transfer the solution until the volume is fixed to the mark.

[0104] Step 3: The impregnation and drying methods of the La-Ru dual-loaded carbon steel cathode are the same as those in Example 1 to obtain a La-Ru dual-loaded carbon steel cathode.

[0105] The carbon steel cathodes obtained in Examples 1-12 and Comparative Examples 1 and 2 were tested for hydrogen evolution performance:

[0106] Test methods include:

[0107] A three-electrode system was used, with the carbon steel cathodes obtained in Examples 1-12 and Comparative Examples 1 and 2 as the working electrode, a saturated calomel electrode as the reference electrode, and a platinum electrode as the counter electrode. Linear voltammetric scans were performed in a simulated circulating water solution with a hardness of 400 mg / L (calculated as CaCO3), with a scan range of 0 to -3 V and a scan rate of 5 mV·s -1 .

[0108] Test results see Figure 1-3 The results show that the Ce-Ru dual-loaded carbon steel cathode provided by Example 10 exhibits the best synergistic effect: at 1 mA·cm -2 At a current density of -1.28 V, its hydrogen evolution potential dropped to -1.28 V, a further decrease of 110 mV compared to the single-loaded Ru@carbon steel cathode (-1.39 V) (Comparative Example 1), and a decrease of 580 mV compared to the blank carbon steel (-1.86 V), a decrease of 32%, which is better than the bimetallic loaded carbon steel cathode provided in other examples. This is because when the Ru / Ce ratio is maintained within the range of Example 10, the full exposure of the Ru active sites and the electronic structure regulation of Ce jointly reduce the energy barrier of the hydrogen evolution reaction, wherein Ce regulates the d-band center position of Ru through electron transfer, thereby reducing the binding energy of hydrogen intermediates; at the same time, the interface anchoring effect of Ce anchors the Ru nanoparticles at the carbon steel substrate interface, limiting their migration and agglomeration, and maintaining a high active site density.

[0109] Referring to ASTM D3359-2017, Standard Test Method for Evaluating Adhesion by Tape Test, the Ce-Ru dual-loaded carbon steel cathodes provided in Examples 9-12 were placed on filter paper. 3M tape was then applied to the cathode surface. Using a rubber eraser of the same width as the 3M tape, the tape surface was rubbed firmly to ensure uniform contact between the tape and the cathode surface. After standing for 20 minutes, the 3M tape was quickly peeled off, and the cathode was weighed. The data are shown in Table 1.

[0110] Table 1 provides a table of cathode material quality changes in Examples 9-12

[0111]

[0112] Combined with the data in Table 1 and see Figure 4 It can be seen that the catalytic layer of the Ce-Ru dual-loaded carbon steel cathode provided in Example 10 is uniform, dense and has good bonding strength.

[0113] In addition, see Figure 1 Among the bimetallic loaded carbon steel cathodes provided in Examples 1-4, the cathode provided in Example 1 has the lowest hydrogen evolution potential of -1.30V, but the carbon steel surface has poor bonding strength and is prone to slagging. The cathode provided in Example 2 has a hydrogen evolution potential as low as -1.34V and, by reducing the Ni content, alleviates the structural distortion and stress problems, maintaining the integrity of the loading layer on the carbon steel cathode surface. Figure 2 Among the bimetallic loaded carbon steel cathodes provided in Examples 5-8, the carbon steel cathode provided in Example 8 not only reduced the hydrogen evolution potential but also alleviated structural distortion and stress issues in the loading layer, maintaining the integrity of the loading layer. The La-Ru dual-loaded carbon steel cathode provided in Comparative Example 2 had a hydrogen evolution potential of -1.41 V at a 1:1 loading molar ratio, higher than the -1.39 V of the Ru-only loaded carbon steel cathode. Furthermore, at this molar ratio, the carbon steel surface exhibited poor bonding strength and prone to slagging.

[0114] like Figure 5 The results are shown in the figure, which is a curve of the open circuit potential of the blank carbon steel and the Ce-Ru dual-loaded carbon steel cathode provided in Example 10 over time. The open circuit potential of the blank carbon steel is stable at around -0.75V (vs. SCE), and the open circuit potential of the Ce-Ru dual-loaded carbon steel cathode is stable at around -0.45V (vs. SCE). The more positive the open circuit potential, the less prone the metal is to corrosion and the stronger the corrosion resistance. Therefore, it can be seen that the corrosion resistance of the Ce-Ru dual-loaded carbon steel cathode is better than that of the blank carbon steel. The Ce-Ru dual loading can effectively improve the corrosion resistance of the carbon steel cathode and reduce its tendency to undergo corrosion reactions such as cathode hydrogen evolution.

[0115] Application Example 1

[0116] The double-loaded carbon steel cathode provided in Example 10 is used as the cathode, and the ruthenium-iridium-titanium mesh is used as the anode. The double-loaded carbon steel cathode is connected to the negative electrode of a regulated DC power supply, and the anode is connected to the positive electrode of the DC power supply to obtain an electrolytic descaling device. The effective capacity of the electrolytic cell of the electrolytic descaling device is 1.5L.

[0117] The distance between the double-loaded carbon steel cathode and the anode is 12 cm, and the electrolyte is simulated circulating water with a hardness of 480 mg / L (calculated as CaCO3).

[0118] During electrolysis, first -2 The pre-electrolysis was carried out at a current density of 0.025A·dm -2 Electrolysis was carried out at a current density of 60 min.

[0119] Application Examples 2-4

[0120] The same as the application example 1, except that the pre-electrolysis current density and electrolysis current density during electrolysis, the application example 2 is 0.05A·dm -2 , Application Example 3 is 0.1A·dm -2 , Application Example 4 is 0.2A·dm -2 .

[0121] A blank carbon steel electrode was used as the cathode and the test was performed under the same conditions as in Application Examples 1-4.

[0122] The test results are shown in Table 2.

[0123] Table 2 Descaling effect data of electrolytic descaling device

[0124]

[0125]

[0126] The experimental results show that in the range of 0.025-0.2A·dm -2 Within the current density range, the electrolysis device using the Ce-Ru@carbon steel cathode provided in Example 10 always has higher hardness and alkalinity removal rates than the blank carbon steel. Especially at 0.025A·dm -2 At low current density, the hardness removal rate increased by 78.3% compared with blank carbon steel.

[0127] It should be understood that the above-described specific embodiments of the present invention are merely illustrative or illustrative of the principles of the present invention and do not constitute limitations of the present invention. Therefore, any modifications, equivalent substitutions, improvements, etc. made without departing from the spirit and scope of the present invention should be included within the scope of protection of the present invention. In addition, the appended claims are intended to cover all variations and modifications that fall within the scope and metes and bounds of the appended claims, or equivalents thereof.

Claims

1. A bimetallic loaded cathode, characterized in that: The metal electrode substrate is prepared by immersing a metal electrode substrate in a mixed solution containing a Ru source and an A metal source, wherein the A metal is selected from any one of Ni, Co, and Ce, the molar ratio of the Ru source to the A metal source is 1-100:1, the molar amount of the Ru source is calculated based on the molar amount of Ru, and the molar amount of the A metal source is calculated based on the molar amount of the A metal, and the metal electrode substrate is carbon steel or stainless steel.

2. The cathode according to claim 1, wherein: Metal A is Ni or Ce, and the molar ratio of the Ru source to the metal A source is 5-50:1; or The A metal is Co, and the molar ratio of the Ru source to the A metal source is 90-100:

1.

3. The cathode according to claim 1, wherein The A metal is Ce, and the molar ratio of the Ru source to the A metal source is 9-11:

1.

4. The method for preparing a cathode according to any one of claims 1 to 3, characterized in that: include: Step 1: Pre-treating the metal electrode substrate; Step 2: Immerse the pretreated metal electrode substrate in a mixed solution containing a Ru source and a metal source for reaction, and dry to obtain a bimetallic loaded metal cathode.

5. The preparation method according to claim 4, characterized in that The reaction in step 2 comprises: The reaction temperature is 20-60°C, and the reaction time is 3-28h.

6. An electrolytic descaling device comprising an electrolyte, a DC power supply, and a cathode connected to the DC power supply, characterized in that: The electrolyte comprises water, and the cathode is any one of the bimetallic loaded cathodes according to any one of claims 1 to 3 and the bimetallic loaded cathodes prepared by the preparation method according to claim 4 or 5.

7. The device according to claim 6, characterized in that The current density of the DC power supply is 0.025-0.2A·dm -2 .

8. The device according to claim 6, characterized in that The initial total hardness of the water is 300-500 mg / L, calculated as CaCO3.

9. An electrolytic descaling method, characterized in that: The method is carried out using the device described in any one of claims 6 to 8.

10. The electrolytic descaling method according to claim 9, characterized in that: include: A certain amount of water to be treated is pre-electrolyzed, wherein the current density of the pre-electrolyzed water is 0.025~0.2A·dm -2 , time is 10-30min; Remove the water after pre-electrolytic descaling, add the water to be treated as electrolyte, and perform electrolytic descaling.

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