Method for deeply separating similar metals based on asymmetric reverse pulse electrolysis
Through asymmetric reverse pulse electrolysis technology, the electronegativity difference between inert metal electrodes and similar metal alloy electrodes is used to achieve efficient separation of similar metals, solving the problems of poor selectivity and high energy consumption in conventional methods, and providing a simple and environmentally friendly separation solution.
Patent Information
- Application Number
- CN202510460356.1
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-04-14
- Publication Date
- 2025-07-08
AI Technical Summary
It is difficult to effectively separate similar metals such as zirconium hafnium, tantalum niobium, titanium vanadium and tungsten molybdenum. Conventional methods have poor selectivity, low separation efficiency, large consumption of chemical reagents, environmental pollution and high energy consumption. Constant current electrolysis leads to deterioration of the microenvironment of the electrode/electrolyte interface, out-of-control reactions and inefficient processes.
Asymmetric reverse pulse electrolysis method is adopted, inert metal electrodes and similar metal alloy electrodes are selected, and forward and reverse currents are applied for pulse electrolysis. Using the electronegativity difference between high-active metals and low-active metals, low-active metals are deposited by forward electrolysis, and the high-active metals are dissolved in reverse electrolysis, and the process is repeated until deep separation is achieved.
It realizes efficient separation of similar metals, the process is simple and easy to control, and does not produce harmful gases, and has good application prospects.
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Figure CN120272987A_ABST
Abstract
Description
Technical Field
[0001] The present invention belongs to the technical field of electrochemistry metallurgy, and particularly relates to a method for deeply separating similar metals based on asymmetric reverse pulse electrolysis. Background Art
[0002] Metal separation technology is of great significance in the fields of mineral processing, metallurgical industry, environmental protection, and resource recovery. Similar metal pairs (such as zirconium-hafnium, tantalum-niobium, titanium-vanadium, and tungsten-molybdenum, etc.) are difficult to be effectively separated by conventional separation methods (such as solvent extraction method, ion exchange method, precipitation method, chemical reduction method, etc.) due to their similar physical and chemical properties, and there are problems such as poor selectivity, low separation efficiency, large consumption of chemical reagents, environmental pollution, high energy consumption, complex process, and safety issues.
[0003] Molten salt electrolytic refining is a promising similar metal separation technology, but it is generally carried out under a constant electrolysis protocol. The constant current electrolysis scheme will inevitably lead to the deterioration of the microenvironment near the electrode / electrolyte interface, inducing reaction out of control and low process efficiency. For example, during continuous electrolysis, the local concentration field, temperature field, and electric field near the electrode will deviate from their initial optimal state. Therefore, competitive side reactions are enhanced, such as the redox of impurities. At the same time, the deterioration of the microenvironment may accelerate the irregular changes in the product morphology and structure, resulting in the formation of slender dendritic crystals or powders, further exacerbating the microenvironment deterioration. Summary of the Invention
[0004] In view of this, some embodiments disclose a method for deeply separating similar metals based on asymmetric reverse pulse electrolysis, including:
[0005] Selecting an inert metal electrode as the first electrode and a similar metal alloy electrode as the second electrode; wherein, the similar metal is composed of a high-activity metal and a low-activity metal, and the content of the low-activity metal is greater than that of the high-activity metal; selecting a eutectic salt electrolyte containing a high-valent salt of the low-activity metal as the molten salt electrolyte;
[0006] Composing an electrolysis system with the first electrode, the second electrode, and the molten salt electrolyte, and performing asymmetric pulse electrolysis to achieve deep separation of similar metals; wherein, the asymmetric pulse electrolysis includes:
[0007] Using the first electrode as the cathode and the second electrode as the anode, and applying a forward current for forward electrolysis;
[0008] Using the second electrode as the cathode and the first electrode as the anode, and applying a reverse current for reverse electrolysis; wherein, the electrolysis current of the forward electrolysis is greater than that of the reverse electrolysis, and after reverse constant current electrolysis, the electrolysis is stopped for a set power-off time;
[0009] Repeating the above process multiple times until deep separation of similar metals is achieved.
[0010] Furthermore, in some embodiments, the method for deep separation of similar metals based on asymmetric reverse pulse electrolysis uses a similar metal alloy electrode made of zirconium-hafnium alloy, niobium-tantalum alloy, titanium-vanadium alloy, or vanadium-chromium alloy.
[0011] In some embodiments, the method for deep separation of similar metals based on asymmetric reverse pulse electrolysis has a mass concentration of 1-20 wt.% of the high-valent salt of the low-activity metal in the molten salt electrolyte.
[0012] In some embodiments, the method for deep separation of similar metals based on asymmetric reverse pulse electrolysis uses K2ZrF6, K2TaF7, or K3VO4 as the high-valent salt of the low-activity metal, and eutectic sodium-potassium salt or eutectic lithium-potassium salt electrolyte as the eutectic salt electrolyte.
[0013] In some embodiments, the method for deep separation of similar metals based on asymmetric reverse pulse electrolysis has a current density of 0.01-10 A·cm -2 for forward electrolysis, and a current density of 5-50 mA·cm -2 for reverse electrolysis. Reverse electrolysis mainly uses the electronegativity difference of similar metals to selectively oxidize and remove the high-activity metal in the forward electrolysis product, while avoiding a large amount of dissolution loss of the low-activity metal. Therefore, the current setting for reverse electrolysis is much lower than that for forward electrolysis.
[0014] In some embodiments, the method for deep separation of similar metals based on asymmetric reverse pulse electrolysis sets the heating temperature of the molten salt electrolyte to 450-750 °C.
[0015] In some embodiments, the method for deep separation of similar metals based on asymmetric reverse pulse electrolysis has a total electrolysis time of 7-17 min during the asymmetric pulse electrolysis process, and a duty cycle of 0.2-0.8.
[0016] In some embodiments, the method for deep separation of similar metals based on asymmetric reverse pulse electrolysis has a longer forward electrolysis time than reverse electrolysis time.
[0017] In some embodiments, the single-pulse forward electrolysis time is set to 2-10 min.
[0018] In some embodiments, the single-pulse reverse electrolysis time is set to 1-2 min.
[0019] In some embodiments, the method for deep separation of similar metals based on asymmetric reverse pulse electrolysis uses NaCl-KCl as the eutectic sodium-potassium salt electrolyte and LiCl-KCl as the eutectic lithium-potassium salt electrolyte.
[0020] The method for deep separation of similar metals based on asymmetric reverse pulse electrolysis disclosed in some embodiments uses K2ZrF6 for the separation of zirconium-hafnium alloys, K2TaF7 for the separation of niobium-tantalum alloys, and K3VO4 for the separation of vanadium-titanium and vanadium-chromium alloys.
[0021] The method for deep separation of similar metals based on asymmetric reverse pulse electrolysis disclosed in the embodiments of the present invention can completely separate the highly active metal from the low-active metal in the similar metal alloy by using the asymmetric reverse pulse electrolysis process. The process flow is simple, easy to control, convenient to operate, and does not generate harmful gases, having good application prospects in the field of separation and purification of similar metal pairs. BRIEF DESCRIPTION OF THE DRAWINGS
[0022] Figure 1 Example 1 Schematic diagram of the electrolysis device disclosed in some embodiments.
[0023] REFERENCE SIGNS
[0024] 1 First electrode 2 Second electrode
[0025] 3 Electrolytic cell 4 Molten salt electrolyte
[0026] 5 Asymmetric reverse pulse electrolysis power supply DETAILED DESCRIPTION OF THE EMBODIMENTS
[0027] The special term "embodiment" used here does not necessarily mean that any embodiment described as "exemplary" is better than or superior to other embodiments. For the performance index tests in the embodiments of the present invention, unless otherwise specified, the conventional test methods in the art are adopted. It should be understood that the terms described in the embodiments of the present invention are only used to describe specific embodiments and are not used to limit the content disclosed in the embodiments of the present invention.
[0028] Unless otherwise specified, the technical and scientific terms used herein have the same meanings as those commonly understood by those of ordinary skill in the technical field to which the embodiments of the present invention belong; other test methods and technical means not specifically noted in the embodiments of the present invention refer to the experimental methods and technical means commonly adopted by those of ordinary skill in the art.
[0029] As used herein, the terms "substantially" and "about" are used to describe minor fluctuations. For example, they can refer to less than or equal to ±5%, such as less than or equal to ±2%, such as less than or equal to ±1%, such as less than or equal to ±0.5%, such as less than or equal to ±0.2%, such as less than or equal to ±0.1%, such as less than or equal to ±0.05%. Numerical data presented or represented herein in a range format are used only for convenience and brevity and should therefore be interpreted flexibly as including not only the values explicitly recited as the bounds of the range but also all individual values or sub-ranges included within that range. For example, a numerical range of "1 to 5%" should be interpreted as including not only the explicitly recited values of 1% to 5% but also the individual values and sub-ranges within the indicated range. Thus, individual values such as 2%, 3.5%, and 4% and sub-ranges such as 1% to 3%, 2% to 4%, and 3% to 5% etc. are included within this numerical range. This principle also applies to ranges that recite only a single numerical value. In addition, such an interpretation applies regardless of the width of the range or the nature of the recited features.
[0030] As used herein, including in the claims, conjunctive terms such as "comprising," "including," "carrying," "having," "containing," "involving," "accommodating," etc. are to be understood as being open-ended, i.e., meaning "including but not limited to." Only the conjunctive terms "consisting of" and "composed of" are closed conjunctive terms.
[0031] To better illustrate the content of the present invention, numerous specific details are given in the following specific embodiments. Those skilled in the art should understand that the present invention can also be implemented without some of these specific details. In the embodiments, some methods, means, instruments, devices, etc. well-known to those skilled in the art are not described in detail in order to highlight the gist of the present invention.
[0032] On the premise of no conflict, the technical features disclosed in the embodiments of the present invention can be arbitrarily combined, and the obtained technical solutions belong to the content disclosed in the embodiments of the present invention.
[0033] In some embodiments, a method for deep separation of similar metals based on asymmetric reverse pulse electrolysis includes:
[0034] A selected inert metal electrode is used as the first electrode, and a similar metal alloy electrode is used as the second electrode; among them, the similar metal is composed of a highly active metal and a low active metal, and the content of the low active metal is greater than that of the highly active metal; a eutectic salt electrolyte containing a high-valent salt of a low active metal is selected as the molten salt electrolyte; among them, the inert metal electrode can be in the shape of a sheet, rod, etc. with regular shapes and smooth surfaces, which is convenient for calculating the current density; the material of the inert metal electrode can be copper or stainless steel; usually, a eutectic sodium-potassium salt or eutectic lithium-potassium salt containing a high-valent salt of a low active metal is used as the molten salt electrolyte and placed in an electrolytic cell to provide a reaction site; the similar metal alloy electrode is usually in the shape of a rod or strip; the cathode and anode are usually placed at the same depth in the electrolyte, which is convenient for calculating the current density;
[0035] An electrolysis system is composed of the first electrode, the second electrode and the molten salt electrolyte to carry out asymmetric pulse electrolysis to achieve deep separation of similar metals; among them, the asymmetric reverse pulse electrolysis includes:
[0036] Using the first electrode as the cathode and the second electrode as the anode, applying a forward current for forward electrolysis; using the second electrode as the cathode and the first electrode as the anode, applying a reverse current for reverse electrolysis; among them, the electrolysis current of forward electrolysis is greater than that of reverse electrolysis, and the electrolysis is stopped after reverse electrolysis for a set power-off time. Repeat the above process multiple times until the deep separation of similar metals is achieved. Usually, asymmetric pulse reverse electrolysis means that the reverse pulse and the forward pulse are asymmetric. The number of repetitions of asymmetric reverse pulse electrolysis is usually determined according to the degree of product separation, and the number of repetitions of asymmetric reverse pulse electrolysis is determined based on the basic principle of meeting the product purity.
[0037] In some embodiments, the deep separation of similar metals based on asymmetric reverse pulse electrolysis is carried out in Figure 1 the device shown, where the inert metal electrode is the first electrode 1, the similar metal alloy electrode is the second electrode 2, the first electrode 1 and the second electrode are set at the same depth in the electrolytic cell 3, and the electrolytic cell 3 is provided with a molten salt electrolyte 3; the first electrode 1 and the second electrode 2 are set to be electrically connected to a pulse power supply 5, and the pulse power supply 5 applies an asymmetric reverse pulse electrolysis current I to the first electrode 1 and the second electrode 2; during the electrolysis process, the forward electrolysis current is greater than the reverse electrolysis current, the forward electrolysis time is greater than the reverse electrolysis time, and the installed forward electrolysis time t on正 and the reverse electrolysis time t on反 and the zero-current power-off time t off are used for electrolysis to form a single pulse cycle; the above single pulse cycle is repeated multiple times to complete the overall asymmetric reverse pulse electrolysis process.
[0038] Generally, during pulse electrolysis, the direction of the current is constantly changed, and the applied voltage or current changes periodically, which can flexibly adjust the microenvironment of the electrode reaction. The pulse electrolysis mode has richer parameters, including waveform, period, and duty cycle. By adjusting these parameters, the microenvironment of the electrode interface can be effectively regulated;
[0039] Asymmetric reverse pulse electrolysis includes two processes: forward electrolysis and reverse electrolysis. Both are constant-current electrolysis. At the same time, forward electrolysis and reverse electrolysis alternate to reflect the pulse law, and a power-off time is added between electrolysis cycles. During the forward electrolysis process, the inert metal electrode is the cathode, and the similar metal alloy is the anode. The highly active metal atoms and low-active metal atoms in the anode enter the molten salt electrolyte in ionic form successively and migrate towards the vicinity of the inert metal cathode, and are further reduced and deposited on the surface of the inert metal electrode in the form of an alloy to obtain the cathode product alloy; among them, the ratio of the content of the low-active metal to the highly active metal in the cathode product alloy is greater than the ratio of the content of the low-active metal to the highly active metal in the similar metal alloy anode used as the anode; during the reverse electrolysis process, the inert metal electrode deposited with the cathode product alloy is used as the anode, and the similar metal alloy is used as the cathode, so that the highly active metal in the cathode product alloy deposited on the inert metal electrode dissolves into the molten salt electrolyte, and the low-active metal remains on the anode, realizing the separation of the highly active metal and the low-active metal.
[0040] Generally, the voltage or current applied in pulse electrolysis changes periodically, which has inherent advantages in flexibly adjusting the microenvironment. The microenvironment of the electrode / electrolyte interface has a significant impact on the electrolysis process. During the forward electrolysis process, metal cations will migrate towards the vicinity of the inert metal cathode and deposit on the cathode. A constant electrolysis process will cause a large amount of cations to accumulate near the cathode, generating a high ion concentration gradient and deteriorating the subsequent deposition process. Applying a reverse current after forward electrolysis can, on the one hand, adjust the ion distribution in the molten salt and improve the microenvironment of the electrolytic electrolyte interface; on the other hand, the selective oxidation of highly active metals at low currents can deepen the degree of separation of similar metals. Therefore, the asymmetric reverse pulse electrolysis proposed in the present invention can achieve deep separation of similar metal pairs through the coupling effect of forward electrolysis and reverse electrolysis.
[0041] The method for deeply separating similar metals based on asymmetric reverse pulse electrolysis disclosed in the embodiments of the present invention strengthens the deposition of low-active metals during forward electrolysis based on the differences in reduction potential and nucleation and growth driving force; during reverse electrolysis, based on the differences in electronegativity of similar metals and the special structure of the product being loose and porous, the highly active metal can be controllably dissolved at low current, thereby realizing deep separation of similar metals.
[0042] The parameters involved in the asymmetric reverse pulse electrolysis process mainly include the period, duty cycle, current density, etc. The period usually refers to the total time in the asymmetric reverse pulse electrolysis process. During the forward electrolysis process, the period is mainly reflected as the forward electrolysis time. By setting the forward electrolysis time in a single pulse process, the thickness of the cathode electrolysis product can be effectively reduced, and the selective oxidation and precipitation of highly active metals during reverse electrolysis can be promoted. During the reverse electrolysis process, the period is mainly reflected as the reverse electrolysis time. By controlling the reverse electrolysis time in a single pulse process, sufficient charge can be provided for the dissolution of highly active metal atoms. The current density mainly involves the magnitude of the current applied during the forward and reverse electrolysis processes. At a certain electrolysis time, an increase in current is beneficial to the dissolution of metals. In the asymmetric reverse pulse electrolysis process, the duty cycle refers to the ratio of the power-off time of the system to the total time, which is equivalent to the ratio of the total power-off time after reverse electrolysis to the total time of the entire asymmetric reverse pulse electrolysis process. By adjusting the duty cycle, a certain power-off time is added between single asymmetric reverse pulses, that is, an electrolysis process in which forward electrolysis, reverse electrolysis, and no current are repeated in sequence for multiple times is formed. The application of the duty cycle can promote the uniform distribution of ions during electrolysis, reduce concentration polarization, and balance the microenvironment of the electrode interface.
[0043] In some embodiments, the method for deeply separating similar metals based on asymmetric reverse pulse electrolysis is disclosed, and the similar metal alloy electrode is a zirconium-hafnium alloy, a niobium-tantalum alloy, a titanium-vanadium alloy, or a vanadium-chromium alloy.
[0044] In some embodiments, the method for deeply separating similar metals based on asymmetric reverse pulse electrolysis is disclosed, and the mass concentration of the high-valent salt of the low-active metal in the molten salt electrolyte is 1-20 wt.%.
[0045] In some embodiments, the method for deeply separating similar metals based on asymmetric reverse pulse electrolysis is disclosed, and the high-valent salt of the low-active metal is K2ZrF6, K2TaF7, or K3VO4, and the eutectic salt electrolyte is a eutectic sodium-potassium salt or a eutectic lithium-potassium salt electrolyte.
[0046] In some embodiments, the method for deeply separating similar metals based on asymmetric reverse pulse electrolysis is disclosed, and the current density of the forward electrolysis is 0.01-10 A·cm -2 , and the current density of the reverse electrolysis is 5-50 mA·cm -2 .
[0047] In some embodiments, the method for deeply separating similar metals based on asymmetric reverse pulse electrolysis is disclosed, and the heating temperature of the molten salt electrolyte is set to 450-750 °C. Generally, the heating temperature of the electrolyte is the temperature maintained during the electrolysis process of the electrolysis system, and this temperature is determined according to the type of the molten salt electrolyte system.
[0048] The method for deep separation of similar metals based on asymmetric reverse pulse electrolysis disclosed in some embodiments. During the asymmetric pulse electrolysis process, the total electrolysis time is 7 to 17 minutes, and the duty cycle is 0.2 to 0.8.
[0049] The method for deep separation of similar metals based on asymmetric reverse pulse electrolysis disclosed in some embodiments has a forward electrolysis time longer than the reverse electrolysis time.
[0050] The method for deep separation of similar metals based on asymmetric reverse pulse electrolysis disclosed in some embodiments uses eutectic sodium-potassium salt electrolyte NaCl-KCl and eutectic lithium-potassium salt electrolyte LiCl-KCl.
[0051] The method for deep separation of similar metals based on asymmetric reverse pulse electrolysis disclosed in some embodiments uses K2ZrF6 for the separation of zirconium-hafnium alloy, K2TaF7 for the separation of niobium-tantalum alloy, and K3VO4 for the separation of vanadium-titanium and vanadium-chromium alloys.
[0052] The following further exemplarily illustrates the technical details in combination with embodiments.
[0053] Example 1
[0054] In Example 1, for the method of deep separation of similar metals based on asymmetric reverse pulse electrolysis, the similar metals are zirconium and hafnium, and it includes:
[0055] Using a metal copper sheet with a regular shape and a smooth surface as the first electrode, and a zirconium-hafnium alloy rod as the second electrode. The zirconium-hafnium alloy rod is composed of hafnium and zirconium, with the content of zirconium being 98.5 wt.%, and the content of hafnium being 1.5 wt.%.
[0056] Using eutectic sodium-potassium salt NaCl-KCl containing 10.0 wt.% K2ZrF6 as the molten salt electrolyte, and setting the first electrode and the second electrode at the same depth in the molten salt electrolyte. The molten salt electrolyte is heated to 750 °C for pulse electrolysis. The pulse electrolysis consists of forward electrolysis and reverse electrolysis. In a single pulse, the forward electrolysis time is set to 2 minutes, the forward electrolysis current density is set to 0.10 A·cm -2 , the reverse electrolysis time is set to 60 seconds, the reverse electrolysis current is 10 mA, the period is 8 minutes, and the duty cycle is 0.375. The asymmetric reverse pulse electrolysis process includes:
[0057] During the forward electrolysis process, the first electrode is used as the cathode and the second electrode is used as the anode for constant-current electrolysis. During the electrolysis process, hafnium and zirconium enter the molten salt electrolyte in ionic form successively and are further reduced and deposited on the surface of the copper sheet in the form of an alloy. Among them, the ratio of the zirconium content to the hafnium content in the alloy is greater than the ratio of the zirconium content to the hafnium content in the zirconium-hafnium alloy. After forward electrolysis, the content of zirconium is 99.9 wt.%, and the content of hafnium is 0.1 wt.%.
[0058] During the reverse electrolysis process, the first electrode with the zirconium-hafnium alloy product attached is used as the anode, and the second electrode is used as the cathode for constant-current electrolysis. During the electrolysis process, the metal hafnium in the anode dissolves into the molten salt electrolyte, and the zirconium metal remains on the anode.
[0059] According to the pulsed power supply method, forward electrolysis, reverse electrolysis, and electrolysis stop are alternately carried out multiple times in sequence, and finally the separation of hafnium and zirconium is achieved to obtain a high-purity zirconium product. Among them, the hafnium content in the high-purity zirconium product is 0.005 wt.%.
[0060] Example 2
[0061] In Example 2, based on the method of deeply separating similar metals by asymmetric reverse pulse electrolysis, the similar metals are tantalum and niobium.
[0062] The specific method refers to Example 1. Among them, the molten salt electrolyte is a eutectic sodium-potassium salt NaCl-KCl containing 10.0 wt.% K2TaF7 to obtain a high-purity tantalum product. Among them, the niobium content in the high-purity tantalum product is 0.008 wt.%.
[0063] Example 3
[0064] In Example 3, based on the method of deeply separating similar metals by asymmetric reverse pulse electrolysis, the similar metals are vanadium and titanium.
[0065] The specific method refers to Example 1. Among them, the molten salt electrolyte is a eutectic sodium-potassium salt NaCl-KCl containing 10.0 wt.% K3VO4 to obtain a high-purity vanadium product. Among them, the titanium content in the high-purity vanadium product is 0.005 wt.%.
[0066] Example 4
[0067] In Example 4, based on the method of deeply separating similar metals by asymmetric reverse pulse electrolysis, the similar metals are vanadium and chromium.
[0068] The specific method refers to Example 1. Among them, the molten salt electrolyte is a eutectic sodium-potassium salt NaCl-KCl containing 15.0 wt.% K3VO4, the period is 6 min, and the duty cycle is 0.5. A high-purity vanadium product is obtained. Among them, the titanium content in the high-purity vanadium product is 0.01 wt.%.
[0069] The method for deep separation of similar metals based on asymmetric reverse pulse electrolysis disclosed in the embodiments of the present invention can completely separate the highly active metal and the low active metal in the similar metal alloy by using the asymmetric reverse pulse electrolysis process. The process flow is simple, easy to control, convenient to operate, and does not generate harmful gases, having good application prospects in the field of separation and purification of similar metal pairs.
[0070] The technical solutions disclosed in the embodiments of the present invention and the technical details disclosed in the embodiments are only exemplary illustrations of the inventive concept of the present invention and do not constitute a limitation on the technical solutions of the embodiments of the present invention. Any conventional changes, substitutions or combinations made to the technical details disclosed in the embodiments of the present invention have the same inventive concept as the present invention and are within the protection scope of the claims of the present invention.
Claims
1. A method for deeply separating similar metals based on asymmetric reverse pulse electrolysis, characterized in that, Including: Selecting an inert metal electrode as the first electrode and a similar metal alloy electrode as the second electrode; wherein, the similar metal is composed of a highly active metal and a low-active metal, and the content of the low-active metal is greater than that of the highly active metal; selecting a eutectic salt electrolyte containing a high-valent salt of the low-active metal as the molten salt electrolyte; Composing an electrolysis system with the first electrode, the second electrode and the molten salt electrolyte, and performing asymmetric pulse electrolysis to achieve deep separation of similar metals; wherein, the asymmetric pulse electrolysis includes: Using the first electrode as the cathode and the second electrode as the anode, and applying a forward current for forward electrolysis; Using the second electrode as the cathode and the first electrode as the anode, and applying a reverse current for reverse electrolysis; wherein, the electrolysis current of the forward electrolysis is greater than that of the reverse electrolysis, and electrolysis is stopped after the reverse electrolysis and a power-off time is set; Repeating the above process multiple times until deep separation of similar metals is achieved.
2. The method for deeply separating similar metals based on asymmetric reverse pulse electrolysis according to claim 1, wherein The similar metal alloy electrode is a zirconium-hafnium alloy, a niobium-tantalum alloy, a titanium-vanadium alloy or a vanadium-chromium alloy.
3. The method for deep separation of similar metals based on asymmetric reverse pulse electrolysis according to claim 1, characterized in that, The mass concentration of the high-valent salt of the low-active metal in the molten salt electrolyte is 1-20 wt.%.
4. The method for deep separation of similar metals based on asymmetric reverse pulse electrolysis according to claim 1, characterized in that, The high-valent salt of the low-active metal is K2ZrF6, K2TaF7 or K3VO4, and the eutectic salt electrolyte is a eutectic sodium-potassium salt or a eutectic lithium-potassium salt electrolyte.
5. The method for deep separation of similar metals based on asymmetric reverse pulse electrolysis according to claim 1, characterized in that, The current density of forward electrolysis is 0.01~10A·cm -2 , the current density of reverse electrolysis is 5~50mA·cm -2 .
6. The method for deep separation of similar metals based on asymmetric reverse pulse electrolysis according to claim 1, characterized in that, The heating temperature of the molten salt electrolyte is set to 450-750 °C.
7. The method for deeply separating similar metals based on asymmetric reverse pulse electrolysis according to claim 1, characterized in that, During the asymmetric pulse electrolysis process, the total electrolysis time is 7-17 min, wherein the duty cycle is 0.2-0.
8.
8. The method for deeply separating similar metals based on asymmetric reverse pulse electrolysis according to claim 1, characterized in that The forward electrolysis time is greater than the reverse electrolysis time.
9. The method for deeply separating similar metals based on asymmetric reverse pulse electrolysis according to claim 4, characterized in that The eutectic sodium-potassium salt electrolyte is NaCl-KCl, and the eutectic lithium-potassium salt electrolyte is LiCl-KCl.
10. The method for deeply separating similar metals based on asymmetric reverse pulse electrolysis according to claim 4, wherein For the separation of zirconium-hafnium alloy, K2ZrF6 is used; for the separation of niobium-tantalum alloy, K2TaF7 is used; for the separation of vanadium-titanium and vanadium-chromium alloys, K3VO4 is used.