Method for electrochemical upgrading and recycling of waste nickel based on a deep eutectic solvent system

Abstract

The application discloses a method for electrochemically upgrading and recycling waste nickel based on a eutectic solvent system, and belongs to the technical field of waste resource recycling and electrochemical catalytic material preparation. The method comprises the following steps: taking a material containing waste nickel as an anode, taking a carrier metal as a cathode, and taking a eutectic solvent as an electrolyte, wherein the electrolyte is dissolved with nickel salt and an additive; through electrodeposition, the nickel in the anode is dissolved out and deposited on the cathode, and the recycling of the waste nickel is completed. The electrochemical upgrading and recycling method based on the eutectic solvent system can efficiently utilize the waste material containing nickel (such as a thermal spraying Reni nickel electrode), and the waste material containing nickel can be used as the anode, so that the green recycling and high-value reuse of the waste nickel resource can be realized. The process is simple in operation, environmentally friendly, and high in resource utilization rate, and has strong industrial application potential and commercial value.

Description

Technical Field

[0001] This invention belongs to the field of waste resource recycling and electrochemical catalytic material preparation technology, specifically relating to a method for electrochemically upgrading and recycling waste nickel based on a eutectic solvent system. Background Technology

[0002] Raney nickel is a porous nickel-aluminum alloy powder catalyst widely used in organic reactions such as hydrogenation, dehydrogenation, dehalogenation, and desulfurization. In the field of water electrolysis for hydrogen production, Raney nickel catalysts are often supported on nickel mesh substrates using techniques such as thermal spraying to construct highly efficient hydrogen evolution Raney nickel electrodes with high specific surface area and abundant active sites. Alkaline water electrolysis is currently the mainstream technology for large-scale industrial hydrogen production, and this type of Raney nickel electrode, as a core cathode material, faces huge market demand.

[0003] In the high-temperature, strongly alkaline, and high-current-density industrial electrolysis environment, a large number of hydrogen bubbles are continuously generated on the surface of the Raney nickel cathode. The intense generation and escape process frequently erodes the electrode surface, causing problems such as the shedding of the Raney nickel active layer and pore blockage. This leads to catalyst activity decay and a continuous decrease in hydrogen evolution efficiency, ultimately resulting in electrode failure and requiring replacement to maintain system performance. The main components of waste Raney nickel electrodes are nickel and its oxides, along with trace amounts of aluminum, giving them significant resource recovery value. However, because this type of waste catalyst is primarily composed of nickel, it has been listed in the "National Hazardous Waste List." Improper disposal could lead to soil and water pollution; therefore, it is essential to carry out standardized recycling and harmless treatment.

[0004] Currently, existing patents mainly target the recovery of Raney nickel powder, and most of them use wet or pyrometallurgical processes to separate nickel and aluminum. However, they all have obvious drawbacks. For example, the commonly used wet treatment often uses concentrated sulfuric acid, hydrochloric acid, or concentrated sodium hydroxide to treat the recovered materials, which not only generates a large amount of wastewater, but also has a complicated overall operation. In contrast, pyrometallurgical recovery requires processing at high temperatures (1500℃), which has the disadvantages of high energy consumption and the generation of a large amount of high-temperature flue gas, requiring the addition of corresponding treatment methods. Summary of the Invention

[0005] The purpose of this invention is to provide a method for electrochemically upgrading and recovering waste nickel based on a eutectic solvent system. This invention proposes to directly utilize waste nickel (such as waste Raney nickel electrodes) as the anode in the electrolysis process, achieving metal recovery through its anodic dissolution reaction, while suppressing side reactions in the process, and preparing a highly active three-dimensional porous nickel electrode. This approach simplifies the recovery process and improves resource utilization, possessing potential research and application value.

[0006] To achieve the above objectives, the present invention provides the following technical solution: One of the technical solutions of this invention is to provide a method for electrochemically upgrading and recovering waste nickel based on a eutectic solvent system, comprising the following steps: Using a material containing waste nickel as the anode, a carrier metal as the cathode, and a eutectic solvent as the electrolyte, the electrolyte contains nickel salts and additives; through electrodeposition, the nickel in the anode is dissolved and deposited on the cathode, thus completing the recycling of waste nickel.

[0007] Optionally, the material containing waste nickel is a waste Raney nickel electrode.

[0008] The recycling technology for waste Raney nickel electrodes utilizes a green electrochemical regeneration process, successfully solving the challenges of heavy metal pollution and nickel resource recycling. Employing a eutectic solvent as the electrolytic support system, its low surface tension (only 1 / 3 to 1 / 2 that of water) allows for thorough penetration of the cathode nickel mesh surface, significantly improving coating uniformity. This system also boasts environmental advantages; the solvent is biodegradable and non-toxic, meeting green manufacturing standards. A dynamic nickel replenishment mechanism using a soluble nickel anode enables continuous nickel ion replenishment, adapting to the demands of continuous industrial production. Furthermore, by controlling electrolysis conditions and combining them with additive strategies, the coating structure can be optimized and a porous surface constructed, effectively reducing hydrogen evolution overpotential. The application of anodic dissolution technology simultaneously suppresses side reactions, achieving an anodic efficiency of over 95%. This not only enhances coating bonding strength and corrosion resistance but also provides a reliable solution for the efficient and environmentally friendly regeneration of industrial nickel electrodes.

[0009] Optionally, the carrier metal is a nickel mesh.

[0010] Preferably, the hydrogen bond acceptor of the eutectic solvent is sodium chloride, the hydrogen bond donor is ethylene glycol, and the molar ratio of the hydrogen bond acceptor to the hydrogen bond donor is 1:(50~70).

[0011] Preferably, the concentration of nickel in the nickel salt in the eutectic solvent is 0.1~0.6M.

[0012] Preferably, the additive is sodium diethyldithiocarbamate.

[0013] More preferably, the concentration of the additive in the eutectic solvent is 1~7mM.

[0014] Preferably, the temperature during electrodeposition is 25~100℃.

[0015] Preferably, the current density during electrodeposition is 2~6 mA / cm². 2 .

[0016] Preferably, during electrodeposition, the charge density is 20~120 C / cm³. 2 .

[0017] The beneficial technical effects of the present invention are as follows: The electrochemical upgrading and recycling method based on a eutectic solvent system proposed in this invention can efficiently utilize nickel-containing waste materials (such as thermally sprayed Raney nickel electrodes) as anodes, enabling green recycling and high-value reuse of waste nickel resources. This process is simple to operate, environmentally friendly, and has high resource utilization, possessing strong potential for industrial application and commercial value. Attached Figure Description

[0018] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the embodiments will be marked below. The drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0019] Figure 1 This is a schematic diagram of the device for electrochemically upgrading and recovering nickel from waste Raney nickel electrodes based on a eutectic solvent system, according to the present invention.

[0020] Figure 2 The melting curve of the waste Raney nickel electrode in Example 25 is shown.

[0021] Figure 3 The images show the XRD patterns of the nickel electrodes prepared in Examples 18 and 25.

[0022] Figure 4 SEM images of the nickel electrodes prepared in Examples 18 and 25 at different magnifications.

[0023] Figure 5 The hydrogen evolution performance of the nickel electrodes prepared in Examples 18 and 25 under operating conditions.

[0024] Figure 6 The nickel electrodes prepared in Examples 18 and 25 are shown to exhibit long-cycle performance under operating conditions.

[0025] Figure 7 The overpotentials of the nickel electrodes prepared in Examples 18 and 25 are the overpotentials corresponding to different time periods over a long period under operating conditions. Detailed Implementation

[0026] Various exemplary embodiments of the present invention will now be described in detail. This detailed description should not be considered as a limitation of the present invention, but rather as a more detailed description of certain aspects, features, and embodiments of the present invention. It should be understood that the terminology used in this invention is merely for describing particular embodiments and is not intended to limit the present invention.

[0027] It should be noted that any aspects not described in detail in this invention are conventional practices in the field and are not the focus of this invention.

[0028] Furthermore, regarding the numerical ranges in this invention, it should be understood that each intermediate value between the upper and lower limits of the range is also specifically disclosed. Any stated value or intermediate value within a stated range, as well as each smaller range between any other stated value or intermediate value within said range, are also included in this invention. The upper and lower limits of these smaller ranges may be independently included or excluded from the range.

[0029] Unless otherwise stated, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art. While only preferred methods and materials have been described herein, any methods and materials similar to or equivalent to those described herein may be used in the implementation or testing of this invention.

[0030] The terms “include,” “including,” “have,” “contain,” etc., used in this article are all open-ended terms, meaning that they include but are not limited to.

[0031] Unless otherwise specified, room temperature in this invention refers to a temperature of 25°C.

[0032] The pure nickel mesh used in the various embodiments of the present invention is a 46-mesh high-purity nickel mesh (wire diameter 0.25 mm, purity ≥99.6%).

[0033] Figure 1 This is a schematic diagram of the device for electrochemically upgrading and recovering nickel from waste Raney nickel electrodes based on a eutectic solvent system, according to the present invention.

[0034] In this invention, the working area of ​​the nickel electrode is 1 cm2, and the operating conditions are that the nickel electrode is placed in a 6 M potassium hydroxide solution and the reaction temperature is maintained at 80°C by an oil bath.

[0035] Example 1 (1) Prepare 50 mL of electrolyte, using 0.3 M sodium chloride-ethylene glycol (molar ratio of sodium chloride to ethylene glycol is 1:60) as the selected eutectic solvent, and nickel chloride concentration of 0.1 M. After weighing the reagent, stir at 300 r / min at 60℃ until the solution turns green and transparent.

[0036] (2) Using a pure nickel mesh as the cathode, the electrode was ultrasonically cleaned for 5 minutes in sequence with 2 M hydrochloric acid, anhydrous ethanol, and pure water. The anode was a used waste Raney nickel electrode, which was cleaned by shaking in pure water at 80°C, then rinsed repeatedly with anhydrous ethanol and pure water, and finally the surface moisture was quickly absorbed with a paper towel and dried with a hair dryer on cold air to ensure the cleanliness of the electrode surface.

[0037] (3) Place the anode and cathode in the electrolytic cell, and press... Figure 1Connect the wires. Electrolyze a nickel electrode at 60°C with a current density of 5 mA / cm² and a charge density of 20 C / cm², resulting in a nickel loading of 5.67 mg / cm².

[0038] (4) Take out the nickel electrode prepared in step (3) and let it stand for five minutes. Then clean it with anhydrous ethanol and pure water in sequence, and then use paper towel to absorb the moisture on the electrode surface.

[0039] (5) The nickel electrode after cleaning in step (4) was tested for hydrogen evolution performance under working conditions on an electrochemical workstation, and the overpotential was measured to be -345 mV with the potential at a current density of 250 mA / cm2 as the reference standard.

[0040] Example 2 (1) Prepare 50 mL of electrolyte, using 0.3 M sodium chloride-ethylene glycol (molar ratio of sodium chloride to ethylene glycol is 1:60) as the selected eutectic solvent, and nickel chloride concentration of 0.2 M. After weighing the reagent, stir at 300 r / min at 60℃ until the solution turns green and transparent.

[0041] (2) Using a pure nickel mesh as the cathode, the electrode was ultrasonically cleaned for 5 minutes in sequence with 2 M hydrochloric acid, anhydrous ethanol, and pure water. The anode was a used waste Raney nickel electrode, which was cleaned by shaking in pure water at 80°C, then rinsed repeatedly with anhydrous ethanol and pure water, and finally the surface moisture was quickly absorbed with a paper towel and dried with a hair dryer on cold air to ensure the cleanliness of the electrode surface.

[0042] (3) Place the anode and cathode in the electrolytic cell, and press... Figure 1 Connect the wires. Electrolyze a nickel electrode at 60°C with a current density of 5 mA / cm² and a charge density of 20 C / cm², resulting in a nickel loading of 5.40 mg / cm².

[0043] (4) Take out the nickel electrode prepared in step (3) and let it stand for five minutes. Then clean it with anhydrous ethanol and pure water in sequence, and then use paper towel to absorb the moisture on the electrode surface.

[0044] (5) The nickel electrode after cleaning in step (4) was tested for hydrogen evolution performance under working conditions on an electrochemical workstation, and the overpotential was measured to be -335 mV with the potential at a current density of 250 mA / cm2 as the reference standard.

[0045] Example 3 (1) Prepare 50 mL of electrolyte, using 0.3 M sodium chloride-ethylene glycol (molar ratio of sodium chloride to ethylene glycol is 1:60) as the selected eutectic solvent, and nickel chloride concentration of 0.3 M. After weighing the reagent, stir at 300 r / min at 60℃ until the solution turns green and transparent.

[0046] (2) Using a pure nickel mesh as the cathode, the electrode was ultrasonically cleaned for 5 minutes in sequence with 2 M hydrochloric acid, anhydrous ethanol, and pure water. The anode was a used waste Raney nickel electrode, which was cleaned by shaking in pure water at 80°C, then rinsed repeatedly with anhydrous ethanol and pure water, and finally the surface moisture was quickly absorbed with a paper towel and dried with a hair dryer on cold air to ensure the cleanliness of the electrode surface.

[0047] (3) Place the anode and cathode in the electrolytic cell, and press... Figure 1 Connect the wires. Electrolyze a nickel electrode at 60°C with a current density of 5 mA / cm² and a charge density of 20 C / cm², resulting in a nickel loading of 5.67 mg / cm².

[0048] (4) Take out the nickel electrode prepared in step (3) and let it stand for five minutes. Then clean it with anhydrous ethanol and pure water in sequence, and then use paper towel to absorb the moisture on the electrode surface.

[0049] (5) The nickel electrode after cleaning in step (4) was tested for hydrogen evolution performance under working conditions on an electrochemical workstation, and the overpotential was measured to be -311 mV with the potential at a current density of 250 mA / cm2 as the reference standard.

[0050] Example 4 (1) Prepare 50 mL of electrolyte, using 0.3 M sodium chloride-ethylene glycol (molar ratio of sodium chloride to ethylene glycol is 1:60) as the selected eutectic solvent, and nickel chloride concentration of 0.4 M. After weighing the reagent, stir at 300 r / min at 60℃ until the solution turns green and transparent.

[0051] (2) Using a pure nickel mesh as the cathode, the electrode was ultrasonically cleaned for 5 minutes in sequence with 2 M hydrochloric acid, anhydrous ethanol, and pure water. The anode was a used waste Raney nickel electrode, which was cleaned by shaking in pure water at 80°C, then rinsed repeatedly with anhydrous ethanol and pure water, and finally the surface moisture was quickly absorbed with a paper towel and dried with a hair dryer on cold air to ensure the cleanliness of the electrode surface.

[0052] (3) Place the anode and cathode in the electrolytic cell, and press... Figure 1Connect the wires. Electrolyze a nickel electrode at 60°C with a current density of 5 mA / cm² and a charge density of 20 C / cm², resulting in a nickel loading of 5.87 mg / cm².

[0053] (4) Take out the nickel electrode prepared in step (3) and let it stand for five minutes. Then clean it with anhydrous ethanol and pure water in sequence, and then use paper towel to absorb the moisture on the electrode surface.

[0054] (5) The nickel electrode after cleaning in step (4) was tested for hydrogen evolution performance under working conditions on an electrochemical workstation, and the overpotential was measured to be -321 mV with the potential at a current density of 250 mA / cm2 as the reference standard.

[0055] Example 5 (1) Prepare 50 mL of electrolyte, using 0.3 M sodium chloride-ethylene glycol (molar ratio of sodium chloride to ethylene glycol is 1:60) as the selected eutectic solvent, and nickel chloride concentration of 0.5 M. After weighing the reagent, stir at 300 r / min at 60℃ until the solution turns green and transparent.

[0056] (2) Using a pure nickel mesh as the cathode, the electrode was ultrasonically cleaned for 5 minutes in sequence with 2 M hydrochloric acid, anhydrous ethanol, and pure water. The anode was a used waste Raney nickel electrode, which was cleaned by shaking in pure water at 80°C, then rinsed repeatedly with anhydrous ethanol and pure water, and finally the surface moisture was quickly absorbed with a paper towel and dried with a hair dryer on cold air to ensure the cleanliness of the electrode surface.

[0057] (3) Place the anode and cathode in the electrolytic cell, and press... Figure 1 Connect the wires. Electrolyze a nickel electrode at 60°C with a current density of 5 mA / cm² and a charge density of 20 C / cm², resulting in a nickel loading of 5.90 mg / cm².

[0058] (4) Take out the nickel electrode prepared in step (3) and let it stand for five minutes. Then clean it with anhydrous ethanol and pure water in sequence, and then use paper towel to absorb the moisture on the electrode surface.

[0059] (5) The nickel electrode after cleaning in step (4) was tested for hydrogen evolution performance under working conditions on an electrochemical workstation, and the overpotential was measured to be -342 mV with the potential at a current density of 250 mA / cm2 as the reference standard.

[0060] Example 6 (1) Prepare 50 mL of electrolyte, using 0.3 M sodium chloride-ethylene glycol (molar ratio of sodium chloride to ethylene glycol is 1:60) as the selected eutectic solvent, and nickel chloride concentration of 0.6 M. After weighing the reagent, stir at 300 r / min at 60℃ until the solution turns green and transparent.

[0061] (2) Using a pure nickel mesh as the cathode, the electrode was ultrasonically cleaned for 5 minutes in sequence with 2 M hydrochloric acid, anhydrous ethanol, and pure water. The anode was a used waste Raney nickel electrode, which was cleaned by shaking in pure water at 80°C, then rinsed repeatedly with anhydrous ethanol and pure water, and finally the surface moisture was quickly absorbed with a paper towel and dried with a hair dryer on cold air to ensure the cleanliness of the electrode surface.

[0062] (3) Place the anode and cathode in the electrolytic cell, and press... Figure 1 Connect the wires. Electrolyze a nickel electrode at 60°C with a current density of 5 mA / cm² and a charge density of 20 C / cm², resulting in a nickel loading of 5.76 mg / cm².

[0063] (4) Take out the nickel electrode prepared in step (3) and let it stand for five minutes. Then clean it with anhydrous ethanol and pure water in sequence, and then use paper towel to absorb the moisture on the electrode surface.

[0064] (5) The nickel electrode after cleaning in step (4) was tested for hydrogen evolution performance under working conditions on an electrochemical workstation, and the overpotential was measured to be -352 mV with the potential at a current density of 250 mA / cm2 as the reference standard.

[0065] Example 7 (1) Prepare 50 mL of electrolyte, using 0.3 M sodium chloride-ethylene glycol (molar ratio of sodium chloride to ethylene glycol is 1:60) as the selected eutectic solvent, and nickel chloride concentration of 0.3 M. After weighing the reagent, stir at 300 r / min at room temperature until the solution turns green and transparent.

[0066] (2) Using a pure nickel mesh as the cathode, the electrode was ultrasonically cleaned for 5 minutes in sequence with 2 M hydrochloric acid, anhydrous ethanol, and pure water. The anode was a used waste Raney nickel electrode, which was cleaned by shaking in pure water at 80°C, then rinsed repeatedly with anhydrous ethanol and pure water, and finally the surface moisture was quickly absorbed with a paper towel and dried with a hair dryer on cold air to ensure the cleanliness of the electrode surface.

[0067] (3) Place the anode and cathode in the electrolytic cell, and press... Figure 1Connect the wires. Under room temperature conditions, control the current density of 5 mA / cm2 and the charge density of 20 C / cm2 to prepare a nickel electrode by electrolysis, with a nickel loading of 1.73 mg / cm2 in the electrode.

[0068] (4) Take out the nickel electrode prepared in step (3) and let it stand for five minutes. Then clean it with anhydrous ethanol and pure water in sequence, and then use paper towel to absorb the moisture on the electrode surface.

[0069] (5) The nickel electrode after cleaning in step (4) was tested for hydrogen evolution performance under working conditions on an electrochemical workstation, and the overpotential was measured to be -407 mV with the potential at a current density of 250 mA / cm2 as the reference standard.

[0070] Example 8 (1) Prepare 50 mL of electrolyte, using 0.3 M sodium chloride-ethylene glycol (molar ratio of sodium chloride to ethylene glycol is 1:60) as the selected eutectic solvent, and nickel chloride concentration of 0.3 M. After weighing the reagent, stir at 300 r / min at 40℃ until the solution turns green and transparent.

[0071] (2) Using a pure nickel mesh as the cathode, the electrode was ultrasonically cleaned for 5 minutes in sequence with 2 M hydrochloric acid, anhydrous ethanol, and pure water. The anode was a used waste Raney nickel electrode, which was cleaned by shaking in pure water at 80°C, then rinsed repeatedly with anhydrous ethanol and pure water, and finally the surface moisture was quickly absorbed with a paper towel and dried with a hair dryer on cold air to ensure the cleanliness of the electrode surface.

[0072] (3) Place the anode and cathode in the electrolytic cell, and press... Figure 1 Connect the wires. Electrolyze a nickel electrode at 40°C with a current density of 5 mA / cm² and a charge density of 20 C / cm², resulting in a nickel loading of 3.60 mg / cm².

[0073] (4) Take out the nickel electrode prepared in step (3) and let it stand for five minutes. Then clean it with anhydrous ethanol and pure water in sequence, and then use paper towel to absorb the moisture on the electrode surface.

[0074] (5) The nickel electrode after cleaning in step (4) was tested for hydrogen evolution performance under working conditions on an electrochemical workstation, and the overpotential was measured to be -345 mV with the potential at a current density of 250 mA / cm2 as the reference standard.

[0075] Example 9 (1) Prepare 50 mL of electrolyte, using 0.3 M sodium chloride-ethylene glycol (molar ratio of sodium chloride to ethylene glycol is 1:60) as the selected eutectic solvent, and nickel chloride concentration of 0.3 M. After weighing the reagent, stir at 300 r / min at 80℃ until the solution turns green and transparent.

[0076] (2) Using a pure nickel mesh as the cathode, the electrode was ultrasonically cleaned for 5 minutes in sequence with 2 M hydrochloric acid, anhydrous ethanol, and pure water. The anode was a used waste Raney nickel electrode, which was cleaned by shaking in pure water at 80°C, then rinsed repeatedly with anhydrous ethanol and pure water, and finally the surface moisture was quickly absorbed with a paper towel and dried with a hair dryer on cold air to ensure the cleanliness of the electrode surface.

[0077] (3) Place the anode and cathode in the electrolytic cell, and press... Figure 1 Connect the wires. Electrolyze a nickel electrode at 80°C with a current density of 5 mA / cm² and a charge density of 20 C / cm², resulting in a nickel loading of 6.20 mg / cm².

[0078] (4) Take out the nickel electrode prepared in step (3) and let it stand for five minutes. Then clean it with anhydrous ethanol and pure water in sequence, and then use paper towel to absorb the moisture on the electrode surface.

[0079] (5) The nickel electrode after cleaning in step (4) was tested for hydrogen evolution performance under working conditions on an electrochemical workstation, and the overpotential was measured to be -335 mV with the potential at a current density of 250 mA / cm2 as the reference standard.

[0080] Example 10 (1) Prepare 50 mL of electrolyte, using 0.3 M sodium chloride-ethylene glycol (molar ratio of sodium chloride to ethylene glycol is 1:60) as the selected eutectic solvent, and nickel chloride concentration of 0.3 M. After weighing the reagent, stir at 300 r / min at 100℃ until the solution turns green and transparent.

[0081] (2) Using a pure nickel mesh as the cathode, the electrode was ultrasonically cleaned for 5 minutes in sequence with 2 M hydrochloric acid, anhydrous ethanol, and pure water. The anode was a used waste Raney nickel electrode, which was cleaned by shaking in pure water at 80°C, then rinsed repeatedly with anhydrous ethanol and pure water, and finally the surface moisture was quickly absorbed with a paper towel and dried with a hair dryer on cold air to ensure the cleanliness of the electrode surface.

[0082] (3) Place the anode and cathode in the electrolytic cell, and press... Figure 1Connect the wires. Electrolyze a nickel electrode at 100°C with a current density of 5 mA / cm² and a charge density of 20 C / cm², resulting in a nickel loading of 5.87 mg / cm².

[0083] (4) Take out the nickel electrode prepared in step (3) and let it stand for five minutes. Then clean it with anhydrous ethanol and pure water in sequence, and then use paper towel to absorb the moisture on the electrode surface.

[0084] (5) The nickel electrode after cleaning in step (4) was tested for hydrogen evolution performance under working conditions on an electrochemical workstation, and the overpotential was measured to be -355 mV with the potential at a current density of 250 mA / cm2 as the reference standard.

[0085] Example 11 (1) Prepare 50 mL of electrolyte, using 0.3 M sodium chloride-ethylene glycol (molar ratio of sodium chloride to ethylene glycol is 1:60) as the selected eutectic solvent, and nickel chloride concentration of 0.3 M. After weighing the reagent, stir at 300 r / min at 60℃ until the solution turns green and transparent.

[0086] (2) Using a pure nickel mesh as the cathode, the electrode was ultrasonically cleaned for 5 minutes in sequence with 2 M hydrochloric acid, anhydrous ethanol, and pure water. The anode was a used waste Raney nickel electrode, which was cleaned by shaking in pure water at 80°C, then rinsed repeatedly with anhydrous ethanol and pure water, and finally the surface moisture was quickly absorbed with a paper towel and dried with a hair dryer on cold air to ensure the cleanliness of the electrode surface.

[0087] (3) Place the anode and cathode in the electrolytic cell, and press... Figure 1 Connect the wires. Electrolyze a nickel electrode at 60°C with a current density of 2 mA / cm² and a charge density of 20 C / cm², resulting in a nickel loading of 5.33 mg / cm².

[0088] (4) Take out the nickel electrode prepared in step (3) and let it stand for five minutes. Then clean it with anhydrous ethanol and pure water in sequence, and then use paper towel to absorb the moisture on the electrode surface.

[0089] (5) The nickel electrode after cleaning in step (4) was tested for hydrogen evolution performance under working conditions on an electrochemical workstation, and the overpotential was measured to be -474 mV with the potential at a current density of 250 mA / cm2 as the reference standard.

[0090] Example 12 (1) Prepare 50 mL of electrolyte, using 0.3 M sodium chloride-ethylene glycol (molar ratio of sodium chloride to ethylene glycol is 1:60) as the selected eutectic solvent, and nickel chloride concentration of 0.3 M. After weighing the reagent, stir at 300 r / min at 60℃ until the solution turns green and transparent.

[0091] (2) Using a pure nickel mesh as the cathode, the electrode was ultrasonically cleaned for 5 minutes in sequence with 2 M hydrochloric acid, anhydrous ethanol, and pure water. The anode was a used waste Raney nickel electrode, which was cleaned by shaking in pure water at 80°C, then rinsed repeatedly with anhydrous ethanol and pure water, and finally the surface moisture was quickly absorbed with a paper towel and dried with a hair dryer on cold air to ensure the cleanliness of the electrode surface.

[0092] (3) Place the anode and cathode in the electrolytic cell, and press... Figure 1 Connect the wires. Electrolyze a nickel electrode at 60°C with a current density of 3 mA / cm² and a charge density of 20 C / cm², resulting in a nickel loading of 5.33 mg / cm².

[0093] (4) Take out the nickel electrode prepared in step (3) and let it stand for five minutes. Then clean it with anhydrous ethanol and pure water in sequence, and then use paper towel to absorb the moisture on the electrode surface.

[0094] (5) The nickel electrode after cleaning in step (4) was tested for hydrogen evolution performance under working conditions on an electrochemical workstation, and the overpotential was measured to be -486 mV with the potential at a current density of 250 mA / cm2 as the reference standard.

[0095] Example 13 (1) Prepare 50 mL of electrolyte, using 0.3 M sodium chloride-ethylene glycol (molar ratio of sodium chloride to ethylene glycol is 1:60) as the selected eutectic solvent, and nickel chloride concentration of 0.3 M. After weighing the reagent, stir at 300 r / min at 60℃ until the solution turns green and transparent.

[0096] (2) Using a pure nickel mesh as the cathode, the electrode was ultrasonically cleaned for 5 minutes in sequence with 2 M hydrochloric acid, anhydrous ethanol, and pure water. The anode was a used waste Raney nickel electrode, which was cleaned by shaking in pure water at 80°C, then rinsed repeatedly with anhydrous ethanol and pure water, and finally the surface moisture was quickly absorbed with a paper towel and dried with a hair dryer on cold air to ensure the cleanliness of the electrode surface.

[0097] (3) Place the anode and cathode in the electrolytic cell, and press... Figure 1Connect the wires. Electrolyze a nickel electrode at 60°C with a current density of 4 mA / cm² and a charge density of 20 C / cm², resulting in a nickel loading of 5.33 mg / cm².

[0098] (4) Take out the nickel electrode prepared in step (3) and let it stand for five minutes. Then clean it with anhydrous ethanol and pure water in sequence, and then use paper towel to absorb the moisture on the electrode surface.

[0099] (5) The nickel electrode after cleaning in step (4) was tested for hydrogen evolution performance under working conditions on an electrochemical workstation, and the overpotential was measured to be -337 mV with the potential at a current density of 250 mA / cm2 as the reference standard.

[0100] Example 14 (1) Prepare 50 mL of electrolyte, using 0.3 M sodium chloride-ethylene glycol (molar ratio of sodium chloride to ethylene glycol is 1:60) as the selected eutectic solvent, and nickel chloride concentration of 0.3 M. After weighing the reagent, stir at 300 r / min at 60℃ until the solution turns green and transparent.

[0101] (2) Using a pure nickel mesh as the cathode, the electrode was ultrasonically cleaned for 5 minutes in sequence with 2 M hydrochloric acid, anhydrous ethanol, and pure water. The anode was a used waste Raney nickel electrode, which was cleaned by shaking in pure water at 80°C, then rinsed repeatedly with anhydrous ethanol and pure water, and finally the surface moisture was quickly absorbed with a paper towel and dried with a hair dryer on cold air to ensure the cleanliness of the electrode surface.

[0102] (3) Place the anode and cathode in the electrolytic cell, and press... Figure 1 Connect the wires. Electrolyze a nickel electrode at 60°C with a current density of 6 mA / cm² and a charge density of 20 C / cm², resulting in a nickel loading of 5.67 mg / cm².

[0103] (4) Take out the nickel electrode prepared in step (3) and let it stand for five minutes. Then clean it with anhydrous ethanol and pure water in sequence, and then use paper towel to absorb the moisture on the electrode surface.

[0104] (5) The nickel electrode after cleaning in step (4) was tested for hydrogen evolution performance under working conditions on an electrochemical workstation, and the overpotential was measured to be -364 mV with the potential at a current density of 250 mA / cm2 as the reference standard.

[0105] Example 15 (1) Prepare 50 mL of electrolyte, using 0.3 M sodium chloride-ethylene glycol (molar ratio of sodium chloride to ethylene glycol is 1:60) as the selected eutectic solvent, and nickel chloride concentration of 0.3 M. After weighing the reagent, stir at 300 r / min at 60℃ until the solution turns green and transparent.

[0106] (2) Using a pure nickel mesh as the cathode, the electrode was ultrasonically cleaned for 5 minutes in sequence with 2 M hydrochloric acid, anhydrous ethanol, and pure water. The anode was a used waste Raney nickel electrode, which was cleaned by shaking in pure water at 80°C, then rinsed repeatedly with anhydrous ethanol and pure water, and finally the surface moisture was quickly absorbed with a paper towel and dried with a hair dryer on cold air to ensure the cleanliness of the electrode surface.

[0107] (3) Place the anode and cathode in the electrolytic cell, and press... Figure 1 Connect the wires. Electrolyze a nickel electrode at 60°C with a current density of 5 mA / cm² and a charge density of 40 C / cm², with a nickel loading of 12.00 mg / cm².

[0108] (4) Take out the nickel electrode prepared in step (3) and let it stand for five minutes. Then clean it with anhydrous ethanol and pure water in sequence, and then use paper towel to absorb the moisture on the electrode surface.

[0109] (5) The nickel electrode after cleaning in step (4) was tested for hydrogen evolution performance under working conditions on an electrochemical workstation, and the overpotential was measured to be -335 mV with the potential at a current density of 250 mA / cm2 as the reference standard.

[0110] Example 16 (1) Prepare 50 mL of electrolyte, using 0.3 M sodium chloride-ethylene glycol (molar ratio of sodium chloride to ethylene glycol is 1:60) as the selected eutectic solvent, and nickel chloride concentration of 0.3 M. After weighing the reagent, stir at 300 r / min at 60℃ until the solution turns green and transparent.

[0111] (2) Using a pure nickel mesh as the cathode, the electrode was ultrasonically cleaned for 5 minutes in sequence with 2 M hydrochloric acid, anhydrous ethanol, and pure water. The anode was a used waste Raney nickel electrode, which was cleaned by shaking in pure water at 80°C, then rinsed repeatedly with anhydrous ethanol and pure water, and finally the surface moisture was quickly absorbed with a paper towel and dried with a hair dryer on cold air to ensure the cleanliness of the electrode surface.

[0112] (3) Place the anode and cathode in the electrolytic cell, and press... Figure 1Connect the wires. Electrolyze a nickel electrode at 60°C with a current density of 5 mA / cm² and a charge density of 60 C / cm², resulting in a nickel loading of 18.56 mg / cm².

[0113] (4) Take out the nickel electrode prepared in step (3) and let it stand for five minutes. Then clean it with anhydrous ethanol and pure water in sequence, and then use paper towel to absorb the moisture on the electrode surface.

[0114] (5) The nickel electrode after cleaning in step (4) was tested for hydrogen evolution performance under working conditions on an electrochemical workstation, and the overpotential was measured to be -333 mV with the potential at a current density of 250 mA / cm2 as the reference standard.

[0115] Example 17 (1) Prepare 50 mL of electrolyte, using 0.3 M sodium chloride-ethylene glycol (molar ratio of sodium chloride to ethylene glycol is 1:60) as the selected eutectic solvent, and nickel chloride concentration of 0.3 M. After weighing the reagent, stir at 300 r / min at 60℃ until the solution turns green and transparent.

[0116] (2) Using a pure nickel mesh as the cathode, the electrode was ultrasonically cleaned for 5 minutes in sequence with 2 M hydrochloric acid, anhydrous ethanol, and pure water. The anode was a used waste Raney nickel electrode, which was cleaned by shaking in pure water at 80°C, then rinsed repeatedly with anhydrous ethanol and pure water, and finally the surface moisture was quickly absorbed with a paper towel and dried with a hair dryer on cold air to ensure the cleanliness of the electrode surface.

[0117] (3) Place the anode and cathode in the electrolytic cell, and press... Figure 1 Connect the wires. Electrolyze a nickel electrode at 60°C with a current density of 5 mA / cm² and a charge density of 80 C / cm², resulting in a nickel loading of 23.73 mg / cm².

[0118] (4) Take out the nickel electrode prepared in step (3) and let it stand for five minutes. Then clean it with anhydrous ethanol and pure water in sequence, and then use paper towel to absorb the moisture on the electrode surface.

[0119] (5) The nickel electrode after cleaning in step (4) was tested for hydrogen evolution performance under working conditions on an electrochemical workstation, and the overpotential was measured to be -331 mV with the potential at a current density of 250 mA / cm2 as the reference standard.

[0120] Example 18 (1) Prepare 50 mL of electrolyte, using 0.3 M sodium chloride-ethylene glycol (molar ratio of sodium chloride to ethylene glycol is 1:60) as the selected eutectic solvent, and nickel chloride concentration of 0.3 M. After weighing the reagent, stir at 300 r / min at 60℃ until the solution turns green and transparent.

[0121] (2) Using a pure nickel mesh as the cathode, the electrode was ultrasonically cleaned for 5 minutes in sequence with 2 M hydrochloric acid, anhydrous ethanol, and pure water. The anode was a used waste Raney nickel electrode, which was cleaned by shaking in pure water at 80°C, then rinsed repeatedly with anhydrous ethanol and pure water, and finally the surface moisture was quickly absorbed with a paper towel and dried with a hair dryer on cold air to ensure the cleanliness of the electrode surface.

[0122] (3) Place the anode and cathode in the electrolytic cell, and press... Figure 1 Connect the wires. Electrolyze a nickel electrode at 60°C with a current density of 5 mA / cm² and a charge density of 100 C / cm², resulting in a nickel loading of 29.67 mg / cm².

[0123] (4) Take out the nickel electrode prepared in step (3) and let it stand for five minutes. Then clean it with anhydrous ethanol and pure water in sequence, and then use paper towel to absorb the moisture on the electrode surface.

[0124] (5) The nickel electrode after cleaning in step (4) was tested for hydrogen evolution performance under working conditions on an electrochemical workstation, and the overpotential was measured to be -308 mV with the potential at a current density of 250 mA / cm2 as the reference standard.

[0125] The XRD and SEM images of the nickel electrode prepared in Example 18 are shown below. Figure 3 and Figure 4 The Ni electrode is shown in the figure. The peaks of the prepared Ni electrode correspond to those of the standard card (PDF#04-0850) of elemental nickel. The morphology is a coarse grain structure with closely packed clusters and a surface composed of fine particles.

[0126] Example 19 (1) Prepare 50 mL of electrolyte, using 0.3 M sodium chloride-ethylene glycol (molar ratio of sodium chloride to ethylene glycol is 1:60) as the selected eutectic solvent, and nickel chloride concentration of 0.3 M. After weighing the reagent, stir at 300 r / min at 60℃ until the solution turns green and transparent.

[0127] (2) Using a pure nickel mesh as the cathode, the electrode was ultrasonically cleaned for 5 minutes in sequence with 2 M hydrochloric acid, anhydrous ethanol, and pure water. The anode was a used waste Raney nickel electrode, which was cleaned by shaking in pure water at 80°C, then rinsed repeatedly with anhydrous ethanol and pure water, and finally the surface moisture was quickly absorbed with a paper towel and dried with a hair dryer on cold air to ensure the cleanliness of the electrode surface.

[0128] (3) Place the anode and cathode in the electrolytic cell, and press... Figure 1 Connect the wires. Electrolyze a nickel electrode at 60°C with a current density of 5 mA / cm² and a charge density of 120 C / cm², resulting in a nickel loading of 36.27 mg / cm².

[0129] (4) Take out the nickel electrode prepared in step (3) and let it stand for five minutes. Then clean it with anhydrous ethanol and pure water in sequence, and then use paper towel to absorb the moisture on the electrode surface.

[0130] (5) The nickel electrode after cleaning in step (4) was tested for hydrogen evolution performance under working conditions on an electrochemical workstation, and the overpotential was measured to be -356 mV with the potential at a current density of 250 mA / cm2 as the reference standard.

[0131] Example 20 (1) Prepare 50 mL of electrolyte. 0.3 M sodium chloride-ethylene glycol (molar ratio of sodium chloride to ethylene glycol is 1:60) is the selected eutectic solvent. Nickel chloride concentration is 0.3 M, and sodium diethyldithiocarbamate concentration is 1 mM as an additive. After weighing the reagents, stir at 300 r / min at 60℃ until the solution turns green and transparent.

[0132] (2) Using a pure nickel mesh as the cathode, the electrode was ultrasonically cleaned for 5 minutes in sequence with 2 M hydrochloric acid, anhydrous ethanol, and pure water. The anode was a used waste Raney nickel electrode, which was cleaned by shaking in pure water at 80°C, then rinsed repeatedly with anhydrous ethanol and pure water, and finally the surface moisture was quickly absorbed with a paper towel and dried with a hair dryer on cold air to ensure the cleanliness of the electrode surface.

[0133] (3) Place the anode and cathode in the electrolytic cell, and press... Figure 1 Connect the wires. Electrolyze a nickel electrode at 60°C with a current density of 5 mA / cm² and a charge density of 100 C / cm², resulting in a nickel loading of 29.67 mg / cm².

[0134] (4) Take out the nickel electrode prepared in step (3) and let it stand for five minutes. Then clean it with anhydrous ethanol and pure water in sequence, and then use paper towel to absorb the moisture on the electrode surface.

[0135] (5) The nickel electrode after cleaning in step (4) was tested for hydrogen evolution performance under working conditions on an electrochemical workstation, and the overpotential was measured to be -260 mV with the potential at a current density of 250 mA / cm2 as the reference standard.

[0136] Example 21 (1) Prepare 50 mL of electrolyte. 0.3 M sodium chloride-ethylene glycol (molar ratio of sodium chloride to ethylene glycol is 1:60) is the selected eutectic solvent. Nickel chloride concentration is 0.3 M, and sodium diethyldithiocarbamate concentration is 2 mM as an additive. After weighing the reagents, stir at 300 r / min at 60℃ until the solution turns green and transparent.

[0137] (2) Using a pure nickel mesh as the cathode, the electrode was ultrasonically cleaned for 5 minutes in sequence with 2 M hydrochloric acid, anhydrous ethanol, and pure water. The anode was a used waste Raney nickel electrode, which was cleaned by shaking in pure water at 80°C, then rinsed repeatedly with anhydrous ethanol and pure water, and finally the surface moisture was quickly absorbed with a paper towel and dried with a hair dryer on cold air to ensure the cleanliness of the electrode surface.

[0138] (3) Place the anode and cathode in the electrolytic cell, and press... Figure 1 Connect the wires. Electrolyze a nickel electrode at 60°C with a current density of 5 mA / cm² and a charge density of 100 C / cm², resulting in a nickel loading of 29.60 mg / cm².

[0139] (4) Take out the nickel electrode prepared in step (3) and let it stand for five minutes. Then clean it with anhydrous ethanol and pure water in sequence, and then use paper towel to absorb the moisture on the electrode surface.

[0140] (5) The nickel electrode after cleaning in step (4) was tested for hydrogen evolution performance under working conditions on an electrochemical workstation, and the overpotential was measured to be -263 mV with the potential at a current density of 250 mA / cm2 as the reference standard.

[0141] Example 22 (1) Prepare 50 mL of electrolyte. 0.3 M sodium chloride-ethylene glycol (molar ratio of sodium chloride to ethylene glycol is 1:60) is the selected eutectic solvent. Nickel chloride concentration is 0.3 M, and sodium diethyldithiocarbamate concentration is 3 mM as an additive. After weighing the reagents, stir at 300 r / min at 60℃ until the solution turns green and transparent.

[0142] (2) Using a pure nickel mesh as the cathode, the electrode was ultrasonically cleaned for 5 minutes in sequence with 2 M hydrochloric acid, anhydrous ethanol, and pure water. The anode was a used waste Raney nickel electrode, which was cleaned by shaking in pure water at 80°C, then rinsed repeatedly with anhydrous ethanol and pure water, and finally the surface moisture was quickly absorbed with a paper towel and dried with a hair dryer on cold air to ensure the cleanliness of the electrode surface.

[0143] (3) Place the anode and cathode in the electrolytic cell, and press... Figure 1 Connect the wires. Electrolyze a nickel electrode at 60°C with a current density of 5 mA / cm² and a charge density of 100 C / cm², resulting in a nickel loading of 29.67 mg / cm².

[0144] (4) Take out the nickel electrode prepared in step (3) and let it stand for five minutes. Then clean it with anhydrous ethanol and pure water in sequence, and then use paper towel to absorb the moisture on the electrode surface.

[0145] (5) The nickel electrode after cleaning in step (4) was tested for hydrogen evolution performance under working conditions on an electrochemical workstation, and the overpotential was measured to be -163 mV with the potential at a current density of 250 mA / cm2 as the reference standard.

[0146] Example 23 (1) Prepare 50 mL of electrolyte. 0.3 M sodium chloride-ethylene glycol (molar ratio of sodium chloride to ethylene glycol is 1:60) is the selected eutectic solvent. Nickel chloride concentration is 0.3 M, and sodium diethyldithiocarbamate concentration is 4 mM as an additive. After weighing the reagents, stir at 300 r / min at 60℃ until the solution turns green and transparent.

[0147] (2) Using a pure nickel mesh as the cathode, the electrode was ultrasonically cleaned for 5 minutes in sequence with 2 M hydrochloric acid, anhydrous ethanol, and pure water. The anode was a used waste Raney nickel electrode, which was cleaned by shaking in pure water at 80°C, then rinsed repeatedly with anhydrous ethanol and pure water, and finally the surface moisture was quickly absorbed with a paper towel and dried with a hair dryer on cold air to ensure the cleanliness of the electrode surface.

[0148] (3) Place the anode and cathode in the electrolytic cell, and press... Figure 1 Connect the wires. Electrolyze a nickel electrode at 60°C with a current density of 5 mA / cm² and a charge density of 100 C / cm², resulting in a nickel loading of 29.67 mg / cm².

[0149] (4) Take out the nickel electrode prepared in step (3) and let it stand for five minutes. Then clean it with anhydrous ethanol and pure water in sequence, and then use paper towel to absorb the moisture on the electrode surface.

[0150] (5) The nickel electrode after cleaning in step (4) was tested for hydrogen evolution performance under working conditions on an electrochemical workstation, and the overpotential was measured to be -168 mV with the potential at a current density of 250 mA / cm2 as the reference standard.

[0151] Example 24 (1) Prepare 50 mL of electrolyte. 0.3 M sodium chloride-ethylene glycol (molar ratio of sodium chloride to ethylene glycol is 1:60) is the selected eutectic solvent. Nickel chloride concentration is 0.3 M, and sodium diethyldithiocarbamate concentration is 5 mM as an additive. After weighing the reagents, stir at 300 r / min at 60℃ until the solution turns green and transparent.

[0152] (2) Using a pure nickel mesh as the cathode, the electrode was ultrasonically cleaned for 5 minutes in sequence with 2 M hydrochloric acid, anhydrous ethanol, and pure water. The anode was a used waste Raney nickel electrode, which was cleaned by shaking in pure water at 80°C, then rinsed repeatedly with anhydrous ethanol and pure water, and finally the surface moisture was quickly absorbed with a paper towel and dried with a hair dryer on cold air to ensure the cleanliness of the electrode surface.

[0153] (3) Place the anode and cathode in the electrolytic cell, and press... Figure 1 Connect the wires. Electrolyze a nickel electrode at 60°C with a current density of 5 mA / cm² and a charge density of 100 C / cm², resulting in a nickel loading of 29.73 mg / cm².

[0154] (4) Take out the nickel electrode prepared in step (3) and let it stand for five minutes. Then clean it with anhydrous ethanol and pure water in sequence, and then use paper towel to absorb the moisture on the electrode surface.

[0155] (5) The nickel electrode after cleaning in step (4) was tested for hydrogen evolution performance under working conditions on an electrochemical workstation, and the overpotential was measured to be -155 mV with the potential at a current density of 250 mA / cm2 as the reference standard.

[0156] Example 25 (1) Prepare 50 mL of electrolyte. 0.3 M sodium chloride-ethylene glycol (molar ratio of sodium chloride to ethylene glycol is 1:60) is the selected eutectic solvent. Nickel chloride concentration is 0.3 M, and sodium diethyldithiocarbamate concentration is 6 mM as an additive. After weighing the reagents, stir at 300 r / min at 60℃ until the solution turns green and transparent.

[0157] (2) Using a pure nickel mesh as the cathode, the electrode was ultrasonically cleaned for 5 minutes in sequence with 2 M hydrochloric acid, anhydrous ethanol, and pure water. The anode was a used waste Raney nickel electrode, which was cleaned by shaking in pure water at 80°C, then rinsed repeatedly with anhydrous ethanol and pure water, and finally the surface moisture was quickly absorbed with a paper towel and dried with a hair dryer on cold air to ensure the cleanliness of the electrode surface.

[0158] (3) Place the anode and cathode in the electrolytic cell, and press... Figure 1 Connect the wires. Electrolyze a nickel electrode at 60°C with a current density of 5 mA / cm² and a charge density of 100 C / cm², resulting in a nickel loading of 29.67 mg / cm².

[0159] (4) Take out the nickel electrode prepared in step (3) and let it stand for five minutes. Then clean it with anhydrous ethanol and pure water in sequence, and then use paper towel to absorb the moisture on the electrode surface.

[0160] (5) The nickel electrode after cleaning in step (4) was tested for hydrogen evolution performance under working conditions on an electrochemical workstation, and the overpotential was measured to be -151 mV with the potential at a current density of 250 mA / cm2 as the reference standard.

[0161] The XRD and SEM images of the nickel electrode prepared in Example 25 are shown below. Figure 3 and Figure 4 The Ni(S) electrode in the image shows that the peaks in the XRD data still appear to be those of elemental nickel, and are broader than those of the Ni electrode. This is attributed to the grain refinement effect of the additives used on the electrode. Figure 4 As shown, the morphology is a cluster structure with tightly packed particles, and the surface is more dense and flat than that of the Ni electrode.

[0162] Example 26 (1) Prepare 50 mL of electrolyte. 0.3 M sodium chloride-ethylene glycol (molar ratio of sodium chloride to ethylene glycol is 1:60) is the selected eutectic solvent. Nickel chloride concentration is 0.3 M, and sodium diethyldithiocarbamate concentration is 7 mM as an additive. After weighing the reagents, stir at 300 r / min at 60℃ until the solution turns green and transparent.

[0163] (2) Using a pure nickel mesh as the cathode, the electrode was ultrasonically cleaned for 5 minutes in sequence with 2 M hydrochloric acid, anhydrous ethanol, and pure water. The anode was a used waste Raney nickel electrode, which was cleaned by shaking in pure water at 80°C, then rinsed repeatedly with anhydrous ethanol and pure water, and finally the surface moisture was quickly absorbed with a paper towel and dried with a hair dryer on cold air to ensure the cleanliness of the electrode surface.

[0164] (3) Place the anode and cathode in the electrolytic cell, and press... Figure 1 Connect the wires. Electrolyze a nickel electrode at 60°C with a current density of 5 mA / cm² and a charge density of 100 C / cm², resulting in a nickel loading of 29.60 mg / cm².

[0165] (4) Take out the nickel electrode prepared in step (3) and let it stand for five minutes. Then clean it with anhydrous ethanol and pure water in sequence, and then use paper towel to absorb the moisture on the electrode surface.

[0166] (5) The nickel electrode cleaned in step (4) was subjected to hydrogen evolution performance testing under operating conditions on an electrochemical workstation, with a current density of 250 mA / cm². 2 Using the overpotential at that time as a reference standard, the measured overpotential was -196 mV.

[0167] Table 1 summarizes the process parameters for preparing nickel electrodes in Examples 1-26.

[0168] Table 1 Table 2 summarizes the data of the nickel electrodes prepared in Examples 1 to 26.

[0169] Table 2 The hydrogen evolution performance of the nickel electrodes prepared in Examples 18 and 25 under operating conditions is shown in the figure. Figure 5 Example 18 corresponds to the Ni (electrode) in the figure, and Example 25 corresponds to the Ni (S) electrode in the figure.

[0170] The long-cycle performance of the nickel electrodes prepared in Examples 18 and 25 under operating conditions is shown in the figure. Figure 6 Example 18 corresponds to the Ni (electrode) in the figure, and Example 25 corresponds to the Ni (S) electrode in the figure. The overpotentials of each electrode under different time periods during long-term operation are shown in the figure. Figure 7 .

[0171] Figure 6 The results show that the Ni (electrode) prepared in Example 18 completely surpasses the base nickel mesh in terms of stability and performance in simulated industrial operation; meanwhile, the Ni (S) electrode prepared in Example 25 after introducing additives surpasses the Raney nickel hydrogen evolution electrode commonly used in alkaline water electrolysis in terms of stability and performance in simulated industrial operation.

[0172] The embodiments described above are merely preferred embodiments of the present invention and are not intended to limit the scope of the present invention. Various modifications and improvements made by those skilled in the art to the technical solutions of the present invention without departing from the spirit of the present invention should fall within the protection scope defined by the claims of the present invention.

Claims

1. A method for electrochemically upgrading and recovering waste nickel based on a eutectic solvent system, characterized in that, Includes the following steps: Using a material containing waste nickel as the anode, a carrier metal as the cathode, and a eutectic solvent as the electrolyte, the electrolyte contains nickel salts and additives; through electrodeposition, the nickel in the anode is dissolved and deposited on the cathode, thus completing the recycling of waste nickel.

2. The method for electrochemical upgrading and recycling of waste nickel based on a eutectic solvent system according to claim 1, characterized in that, The material containing waste nickel is a waste Raney nickel electrode.

3. The method for electrochemical upgrading and recycling of waste nickel based on a eutectic solvent system according to claim 1, characterized in that, The hydrogen bond acceptor of the eutectic solvent is sodium chloride, and the hydrogen bond donor is ethylene glycol. The molar ratio of the hydrogen bond acceptor to the hydrogen bond donor is 1:(50~70).

4. The method for electrochemical upgrading and recycling of waste nickel based on a eutectic solvent system according to claim 1, characterized in that, The nickel concentration in the nickel salt of the eutectic solvent is 0.1~0.6M.

5. The method for electrochemical upgrading and recycling of waste nickel based on a eutectic solvent system according to claim 1, characterized in that, The additive is sodium diethyldithiocarbamate.

6. The method for electrochemical upgrading and recycling of waste nickel based on a eutectic solvent system according to claim 5, characterized in that, The concentration of the additive in the eutectic solvent is 1~7mM.

7. The method for electrochemical upgrading and recycling of waste nickel based on a eutectic solvent system according to claim 1, characterized in that, During electrodeposition, the temperature is 25~100℃.

8. The method for electrochemical upgrading and recycling of waste nickel based on a eutectic solvent system according to claim 1, characterized in that, During electrodeposition, the current density is 2~6 mA / cm². 2 .

9. The method for electrochemical upgrading and recycling of waste nickel based on a eutectic solvent system according to claim 1, characterized in that, During electrodeposition, the charge density is 20~120 C / cm³. 2 .

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