Sulfur isotope electrochemical separation method
The electrochemical separation method using multi-stage series metal-sulfur batteries solves the problems of high energy consumption and environmental unfriendliness in existing technologies, achieving efficient and high-purity sulfur isotope separation, which is suitable for high-end industrial applications.
Patent Information
- Application Number
- CN202511165609.9
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-08-20
- Publication Date
- 2025-11-18
AI Technical Summary
Existing technologies for separating 34S and 32S are energy-intensive, involve complex equipment, are costly, and are environmentally unfriendly, making it difficult to meet the production needs of high-purity sulfur isotopes.
A multi-stage series metal-sulfur battery electrochemical separation method is adopted. Through the cascade design of the initial electrolytic cell and the 34S and 32S collecting electrolytic cells, the 34S and 32S are enriched on the depleted electrode and the enriching electrode, respectively, by using electrochemical redox reactions to achieve efficient separation.
It significantly improves separation efficiency, yields high-abundance 32S and 34S products, is suitable for the industrial production of high-purity sulfur isotopes, and is flexible in operation, easy to maintain and expand.
Smart Images
Figure CN120960985A_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The present application belongs to the technical field of sulfur isotope separation, and particularly relates to a method for electrochemical separation of sulfur isotopes. BACKGROUND
[0002] Sulfur element has multiple stable isotopes, among which 32 S (abundance about 94.99%) and 34 S (abundance about 4.25%) are the two with the highest content in nature. The mass difference of the two can be utilized in the field of precision science and high-end industrial applications, so that their separation has important theoretical value and practical significance. For example, in the research of nuclear energy and nuclear fusion, 34 S and 32 S are considered as alternative target materials or tracers due to their nuclear physical characteristics in some reaction paths.
[0003] Traditional isotope separation methods mainly include gas diffusion method, gas centrifuge method and chemical exchange method. Since 34 S and 32 S have relatively close masses, the above traditional methods have problems such as high energy consumption, complex equipment, high operation and maintenance cost, etc. Especially the chemical exchange method uses chemical reagents with high toxicity, strong corrosion or environmental unfriendliness, which further increases the process complexity and production cost. Therefore, it is urgent to develop a new sulfur isotope separation technology with low energy consumption, simple operation, environmental friendliness, wide application range and high separation efficiency, so as to meet the increasing demand for high-purity sulfur isotopes in modern scientific research and high-end industries. SUMMARY
[0004] In view of the above problems, the present application provides a method for electrochemical separation of sulfur isotopes, comprising:
[0005] S1: preparing a plurality of electrolytic cells and dividing them into three groups, which are initial electrolytic cells, set 32 S electrolytic cell group and set 34 S electrolytic cell group, set 34 S electrolytic cell group includes a plurality of set 34 S electrolytic cells for fractional enrichment of 34 S; set 32 S electrolytic cell group includes a plurality of set 32 S electrolytic cells for fractional enrichment of 32 S;
[0006] S2: installing an initial depletion electrode and an enrichment electrode one in the initial electrolytic cell, and installing an enrichment electrode two in all set 34 S electrolytic cells, and installing an enrichment electrode three in all set 32S electrolytic cell is installed with enrichment electrode three respectively; all electrolytic cells are injected with electrolyte;
[0007] S3: the pair of electrodes of the initial electrolytic cell is subjected to charge and discharge cycle, 32 S is enriched on the enrichment electrode one, 34 S is enriched on the depletion electrode;
[0008] S4: the initial depletion electrode is sequentially put into each set 34 S electrolytic cell as a depletion electrode, each set 34 S electrolytic cell, the initial depletion electrode and enrichment electrode two are subjected to charge and discharge cycle, 34 S electrolytic cell, 34 S all are enriched on the initial depletion electrode;
[0009] S5: the enrichment electrode one is put into the first set 32 S electrolytic cell as a depletion electrode, the enrichment electrode one and enrichment electrode three are subjected to charge and discharge cycle, 32 S is enriched on the enrichment electrode three; the first set 32 S electrolytic cell is put into the second set 32 S electrolytic cell as a depletion electrode, the second set 32 S electrolytic cell, 32 S is enriched on the original enrichment electrode three of the electrolytic cell; the operation is repeated until the last set 32 S electrolytic cell.
[0010] The application is based on the principle of electrochemical separation of sulfur isotopes of metal-sulfur battery, through charge / discharge treatment of metal-sulfur battery, enrichment 34 S on the positive electrode side, 32 S on the negative electrode side. However, the separation efficiency of single-stage metal-sulfur battery is insufficient, and it is difficult to meet the production demand of high-purity sulfur isotopes (such as abundance > 99%); the fixed and non-replaceable electrode structure not only limits the capacity improvement, but also increases the maintenance difficulty. Therefore, the electrochemical separation method of the above-mentioned cascade expansion and continuous operation is designed, and the cascade design can amplify the isotope abundance gradient step by step, has high separation efficiency and high product purity, and is suitable for industrialized production of high-purity sulfur isotopes.
[0011] Specifically, the application sets initial electrolytic cell, set 32 S electrolytic cell group and set 34 S electrolytic cell group, which are respectively used for preliminary separation of sulfur isotopes, step-by-step enrichment 32 S, step-by-step enrichment 34 S, each electrolytic cell has a pair of electrodes and electrolyte during operation. Modular electrolytic cell is used as a basic separation unit, through electrochemical oxidation-reduction reaction,32 S is selectively enriched on the enrichment electrode, 34 S is selectively enriched on the depletion electrode, realizing efficient separation of sulfur isotopes. Two groups of electrolytic cells are connected in series to form a multi-stage system, and the isotope abundance gradient transmission chain is formed by the inter-stage transfer and combination of electrodes, which significantly improves the separation efficiency, and finally obtains high abundance of 32 S and 34 S product, the method provided by the present application is flexible, easy to maintain and expand.
[0012] Optionally, each electrolytic cell comprises a cell body and two electrode grooves in the cell body, the cell body is a cube, and the two electrode grooves are respectively arranged on the opposite two sides of the cell body; the electrode groove is vertical, and the top surface and the side surface facing the inside of the cell body are both empty, so that the electrolyte in the cell body can enter and exit the electrode groove, and the depletion electrode or the enrichment electrode is inserted from the top surface of the corresponding electrode groove, and the two side edges of the empty side surface of the electrode groove are respectively provided with a baffle which protrudes into the inside of the cell body and is used to abut against the side surface of the electrode to clamp the electrode in the electrode groove, realizing repeated insertion and extraction operation of the electrode.
[0013] Further optionally, each electrolytic cell is equipped with a power supply, when the electrolytic cell is discharged, the positive electrode of the power supply is electrically connected with the enrichment electrode, and the negative electrode is electrically connected with the depletion electrode; when the electrolytic cell is charged, the positive electrode of the power supply is electrically connected with the depletion electrode, and the negative electrode is electrically connected with the enrichment electrode; the electrode groove is provided with an electrical connection interface, which can realize quick replacement of the electrode and in-situ electrochemical performance calibration;
[0014] The electrolytic cell is provided with a sealing structure to ensure the air tightness and ion isolation of the electrolytic cell during operation. The sealing structure can be a conventional sealing structure in the art.
[0015] The depletion electrode and the enrichment electrode are conventional electrodes; the depletion electrode has a conductive matrix filled with sulfur material, and the sulfur material is selected from at least one of monoclinic sulfur positive electrode material and orthorhombic sulfur positive electrode material. The conductive matrix is a porous conductive material commonly used in the preparation of sulfur-containing electrodes in the field of electrochemistry, including but not limited to one or more of graphite, carbon nanotube, graphene, carbon fiber, conductive carbon black, porous carbon, hollow carbon sphere, ketchen black, foamed copper, foamed nickel, titanium dioxide, vanadium pentoxide, manganese dioxide, titanium nitride, titanium carbide, cobalt selenide, cobalt diselenide, and nickel selenide. The depletion electrode is a composite of monoclinic sulfur / orthorhombic sulfur and a conductive substrate, in which the stable sulfur isotopes account for 10-90wt%. The enrichment electrode has a conductive matrix filled with active metal, and the active metal includes one or more of lithium, sodium, potassium, calcium, magnesium, aluminum, and other alkali metals or alkaline earth metals.
[0016] The materials of the enrichment electrodes one, two and three are the same. The initial depletion electrode is the depletion electrode.
[0017] Optionally, in step S2, the initial electrolytic cell is inserted with the enrichment electrode one in the right electrode groove and the initial depletion electrode in the left electrode groove; each set 34 S of enrichment electrodes is inserted in the right electrode groove of the electrolytic cell and the left electrode groove is left empty; each set 32 S of enrichment electrodes is inserted in the right electrode groove of the electrolytic cell and the left electrode groove is left empty.
[0018] Optionally, the ionic conductivity of the electrolyte is greater than 1.0×10 -6 S / cm, and the existing forms of sulfur element include S 2- , S n 2- , SO x 2- , N(CF3SO2)2 2- , N(SO2F)2 2- The solvent medium is aqueous or non-aqueous, n=2-8, and x=3 or 4.
[0019] Optionally, the distance between the depletion electrode and the enrichment electrode in the electrolytic cell is 0.2-2.0 mm, and the current in steps S3-S5 is 0.05-0.8 C.
[0020] Further optionally, the electrolytic cell is provided with a temperature adjusting device and a pH adjusting device, and the power supply can also adjust the potential and the current, so as to control the electrochemical reaction conditions of the electrolytic cell and optimize the isotopic separation coefficient and the separation efficiency.
[0021] Optionally, in step S3, the power supply of the initial electrolytic cell charges and discharges the enrichment electrode one and the initial depletion electrode for several times, 32 S enriches on the enrichment electrode one, and the corresponding depletion occurs on the initial depletion electrode, which is the first-stage 32 S enrichment. 34 S enriches on the depletion electrode, and the corresponding depletion occurs on the enrichment electrode one, which is the first-stage 34 S enrichment, realizing the preliminary separation of sulfur isotopes.
[0022] Optionally, the initial electrolytic cell and each set 34 S of electrolytic cells form a first cascade, which is used for enriching 34 S; in the initial electrolytic cell, 34 S the enrichment is on the initial depletion electrode;
[0023] Then in step S4, the initial depletion electrode is inserted into the left electrode groove of the first set 34 S of electrolytic cells as a depletion electrode, together with the original enrichment electrode two, to charge and discharge for several times, and the 34 S in the electrolyte is enriched on the initial depletion electrode, which is the second-stage 34 S enrichment.
[0024] Then insert the initial depleted electrode into the second set. 34 The left electrode slot of the S electrolytic cell acts as a depleted electrode, and together with the original enriching electrode 2 of the electrolytic cell, it undergoes several charging and discharging processes. The electrolyte... 34 S remains enriched on the initially depleted electrode; this is the third stage. 34 S enrichment;
[0025] This process is repeated until the initial depleted electrode is in the last set. 34 Completed in S electrolytic cell 34 S enrichment, where the initial depleted electrode is the product output terminal, can achieve the target. 34 S purity.
[0026] Optionally, the initial electrolytic cell and each collection 32 The S-electrolysis cell forms the second stage, used for enrichment. 32 S; In the initial electrolytic cell 32 S is enriched on enrichment electrode one;
[0027] Then in step S5, the enrichment electrode one serves as the material input end, and the first enrichment electrode is inserted... 32 The left electrode slot of the S electrolytic cell acts as a depleted electrode, undergoing several charge-discharge cycles together with the original enrichment electrode. The electrolyte and the enrichment electrode... 32 S is enriched on the third enrichment electrode, which is a secondary enrichment. 32 S enrichment;
[0028] Then the first episode 32 The enrichment electrode of the S electrolytic cell is inserted into the second collector. 32 The left electrode slot of the S-electrolytic cell acts as a depleted electrode, in conjunction with the second collection. 32 The original enrichment electrodes of the S electrolytic cell, together with the three electrodes, undergo several charging and discharging processes, resulting in electrolyte and depleted electrodes. 32 S in the second episode 32 The enrichment electrode of the S electrolytic cell is enriched on three levels, which is a three-stage process. 32 S enrichment;
[0029] This process is repeated until the last episode. 32 Completed in the S electrolytic cell 32 S-enrichment, the last set 32 The original enrichment electrode three of the S electrolytic cell is the product output terminal, which can achieve the target. 32 S purity.
[0030] The first and second cascades of this invention possess isotopic abundance gradient transfer characteristics, and the enrichment electrode formed after the initial electrolytic cell is charged / discharged constitutes... 32The starting end of the S isotope enrichment chain, the initial depleted electrode constitutes 34 The starting end of the S isotope enrichment chain, the initial depleted electrode constitutes 32 The S electrolytic cell group and the set 34 The cumulative enrichment effect of the S electrolytic cell group is achieved by electrode replacement to iteratively enhance.
[0031] In each electrolytic cell, only the depleted electrode contains sulfur, and different charge / discharge protocols are applied to the two electrodes by the power supply, so that the sulfur element of the depleted electrode undergoes an electrochemical redox reaction to form polysulfides, which are dissolved into the electrolyte, 34 S is enriched on the depleted electrode, 32 S is enriched on the enriched electrode. When the purity of the corresponding sulfur isotopes on the two electrode surfaces reaches the transfer threshold, the above electrode transfer can be performed, until the purity of the product output end reaches the target purity.
[0032] Optionally, the purity of the product output end is detected by a conventional isotope detection device, including but not limited to inductively coupled plasma mass spectrometry, time-of-flight secondary ion mass spectrometry, gas isotope mass spectrometry, thermal ionization mass spectrometry, and laser-induced breakdown spectroscopy, which can be used together or alone. 32 S is enriched on the depleted electrode, 32 S is enriched on the enriched electrode. When the purity of the corresponding sulfur isotopes on the two electrode surfaces reaches the transfer threshold, the above electrode transfer can be performed, until the purity of the product output end reaches the target purity. 34 S is enriched on the depleted electrode, 34 S is enriched on the enriched electrode. When the purity of the corresponding sulfur isotopes on the two electrode surfaces reaches the transfer threshold, the above electrode transfer can be performed, until the purity of the product output end reaches the target purity. BRIEF DESCRIPTION OF DRAWINGS
[0033] Figure 1 A schematic diagram of the method of electrochemical separation of sulfur isotopes is shown.
[0034] Figure 2 A top view of the electrolytic cell is shown.
[0035] In the drawings, 1 is the initial electrolytic cell, 2 is the set 34 S electrolytic cell, 3 is the set 32 S electrolytic cell, 4 is the initial depleted electrode, 5 is the enriched electrode one, 6 is the enriched electrode two, 7 is the enriched electrode three, 8 is the cell body, 9 is the electrode slot, and 10 is the baffle. DETAILED DESCRIPTION
[0036] Example 1
[0037] This embodiment provides a method for electrochemical separation of sulfur isotopes, as shown in the following schematic diagram: Figure 1 The method comprises the following steps:
[0038] S1: Prepare five electrolytic cells and divide them into three groups, namely the initial electrolytic cell 1, the set 32 S electrolytic cell group and the set 34 S electrolytic cell group, the set 34 S electrolytic cell group comprises two sets 34S electrolytic cell 2 for fractional enrichment 34 S;set 32 S electrolytic cell group includes two sets 32 S electrolytic cell 3 for fractional enrichment 32 S;
[0039] S2: install initial depletion electrode 4 and enrichment electrode one 5 in initial electrolytic cell, install enrichment electrode two 6 in each set 34 S electrolytic cell, install enrichment electrode three 7 in each set 32 S electrolytic cell respectively; all electrolytic cells are injected with electrolyte;
[0040] S3: charge and discharge cycle for a pair of electrodes of initial electrolytic cell, 32 S enrichment on enrichment electrode one, 34 S enrichment on depletion electrode;
[0041] S4: sequentially place initial depletion electrode into each set 34 S electrolytic cell as depletion electrode, sequentially charge and discharge cycle for initial depletion electrode and enrichment electrode two of set 34 S electrolytic cell, 34 S electrolytic cell, 34 S all enrichment on initial depletion electrode;
[0042] S5: place enrichment electrode one into first set 32 S electrolytic cell as depletion electrode, charge and discharge cycle for enrichment electrode one and enrichment electrode three, 32 S enrichment on enrichment electrode three; then place enrichment electrode three of first set 32 S electrolytic cell into second set 32 S electrolytic cell as depletion electrode, charge and discharge cycle for second set 32 S electrolytic cell, 32 S enrichment on original enrichment electrode three of this electrolytic cell; repeat the operation until the last set 32 S electrolytic cell.
[0043] As Figure 2 shown, each electrolytic cell includes cell body 8 and two electrode slots 9 in cell body, cell body is a cube, two electrode slots are respectively arranged on opposite two sides of cell body; electrode slots are vertical, top surface and side surface facing inside of cell body are empty, so that electrolyte in cell body can enter and exit electrode slots, depletion electrode or enrichment electrode is inserted from top surface of corresponding electrode slot, two side edges of empty side surface of electrode slot are respectively provided with baffle 10, baffle protrudes into inside of cell body, used for abutting against side surface of electrode, clamping electrode in electrode slot, realizing repeated insertion and extraction operation of electrode.
[0044] Each electrolytic cell is equipped with a power supply, when the electrolytic cell is discharged, the positive electrode of the power supply is electrically connected to the enrichment electrode, and the negative electrode is electrically connected to the depletion electrode; when the electrolytic cell is charged, the positive electrode of the power supply is electrically connected to the depletion electrode, and the negative electrode is electrically connected to the enrichment electrode; the electrode groove is provided with an electrical connection interface; the electrolytic cell is provided with a sealing structure to ensure the air tightness and ion isolation of the electrolytic cell during operation. After replacing the electrode each time, the sealing structure is resealed.
[0045] Preparation of enrichment electrode and depletion electrode:
[0046] The natural sulfur powder and Ketjen black are mixed by grinding in a mass ratio of 8:2, sealed in an argon atmosphere container, heated to 120℃ and kept for 6 hours. The above-mentioned sulfur-carbon composite material, conductive additive (Super P) and polyvinylidene fluoride (PVDF) binder are mixed in a mass ratio of 8:1:1 in 1-methyl-2-pyrrolidone (NMP) solvent to grind uniformly, to obtain a slurry, then the slurry is scraped onto a three-dimensional nickel foam, and after drying at 60℃ for 24 hours, a 50cm×30cm rectangular electrode piece is cut out as the depletion electrode.
[0047] The three-dimensional copper mesh is cut into a 50cm×30cm rectangular electrode piece, which is immersed in preheated molten liquid metal lithium under an argon atmosphere to obtain the enrichment electrode. The materials of enrichment electrodes one, two and three are the same. The initial depletion electrode is the depletion electrode.
[0048] In step S2, the enrichment electrode one is inserted into the right electrode groove of the initial electrolytic cell, and the initial depletion electrode is inserted into the left electrode groove; the enrichment electrode two is inserted into the right electrode groove of each electrolytic cell in step S3, and the left electrode groove is empty; the enrichment electrode three is inserted into the right electrode groove of each electrolytic cell in step S4, and the left electrode groove is empty. 3L of electrolyte is injected into each electrolytic cell. 34 S The enrichment electrode two is inserted into the right electrode groove of each electrolytic cell in step S3, and the left electrode groove is empty; the enrichment electrode three is inserted into the right electrode groove of each electrolytic cell in step S4, and the left electrode groove is empty. 3L of electrolyte is injected into each electrolytic cell. 32 S The enrichment electrode three is inserted into the right electrode groove of each electrolytic cell in step S4, and the left electrode groove is empty. 3L of electrolyte is injected into each electrolytic cell.
[0049] The distance between the depletion electrode and the enrichment electrode in the electrolytic cell is 0.2mm.
[0050] The electrolyte is specifically 1mol / L of LiTFSI (lithium bis(trifluoromethanesulfonyl) imide), and the solvent is DOL (1,3-dioxolane) and DME (ethylene glycol dimethyl ether) in a volume ratio of 1:1.
[0051] The electrolytic cell is provided with a temperature adjusting device and a pH adjusting device, and the power supply can also adjust the potential and current, which are used to control the electrochemical reaction conditions of the electrolytic cell.
[0052] In step S3, the power supply of the initial electrolytic cell discharges the enrichment electrode one and the initial depletion electrode at 0.05C (1C=1000mAh / g), and then charges at 0.05C, one discharge and one charge being one cycle, which is repeated for 5 cycles,32 S is enriched at the enrichment electrode and simultaneously depleted at the initial depletion electrode; this is the first stage. 32 S enrichment; 34 S is enriched on the depleted electrode, and correspondingly depleted on the enriched electrode; this is the first stage. 34 S enrichment.
[0053] In step S4, the initial depleted electrode serves as the material input terminal, and the first collection is inserted. 34 The left electrode slot of the S electrolytic cell acts as a depleted electrode, and together with the original enriched electrode, it undergoes the aforementioned charging and discharging process. The electrolyte contains... 34 S is enriched on the initially depleted electrode; this is secondary. 34 S enrichment;
[0054] Then insert the initial depleted electrode into the second set. 34 The left electrode slot of the S electrolytic cell acts as a depleted electrode, and together with the original enriched electrode, it undergoes the aforementioned charging and discharging process. The electrolyte contains... 34 S remains enriched on the initially depleted electrode; this is the third stage. 34 S enrichment.
[0055] In step S5, the enrichment electrode one serves as the material input end, and the first enrichment electrode is inserted. 32 The left electrode slot of the S electrolytic cell acts as a depleted electrode, and together with the original enriching electrode three, it undergoes the aforementioned charging and discharging process. The electrolyte and the enriching electrode one... 32 S is enriched on the third enrichment electrode, which is a secondary enrichment. 32 S enrichment;
[0056] Then the first episode 32 The enrichment electrode of the S electrolytic cell is inserted into the second collector. 32 The left electrode slot of the S-electrolytic cell acts as a depleted electrode, in conjunction with the second collection. 32 Together with the enrichment electrode of the S electrolytic cell, the above-mentioned charging and discharging processes are carried out, and the electrolyte and the depleted electrode are... 32 S in the second episode 32 The enrichment electrode of the S electrolytic cell is enriched on three levels, which is a three-stage process. 32 S enrichment.
[0057] In steps S3-S5, the current applied to each electrolytic cell is 0.05C.
[0058] Finally, the collection 34 S electrolytic cells and collection 32 The S electrolytic cell was disassembled, each electrode was removed, a small piece of material was cut from the electrode, dissolved in 0.1 mol / L NaOH solution, and diluted 200 times with deionized water. The diluted solution was then tested by ICP-MS.
[0059] Table 1 enrichment effect of each stage of sulfur isotope of Example 1
[0060]
[0061] Note: at% is 32 S and 34 S atomic percentage.
[0062] From the above table, on the first cascade, the 34 S purity gradually increased from 6.2at% to 9.6at%; on the second cascade, the 32 S purity gradually increased, and finally reached 99.1at%, indicating that the present application can realize efficient isotope separation.
[0063] Comparative Example 1
[0064] The method of electrochemical separation of sulfur isotopes of the present comparative example is the same as that of Example 1, the difference is that only the initial electrolytic cell, from Table 1, the 34 S purity of the depleted electrode is only 6.2at%, and the 32 S purity of the enriched electrode is 98.2at%, which is significantly lower than that of Example 1.
[0065] Example 2
[0066] The method of electrochemical separation of sulfur isotopes of the present example is the same as that of Example 1, the difference is that the distance between the depleted electrode and the enriched electrode in the electrolytic cell is 2.0mm.
[0067] Example 3
[0068] The method of electrochemical separation of sulfur isotopes of the present example is the same as that of Example 1, the difference is that the distance between the depleted electrode and the enriched electrode in the electrolytic cell is 2.1mm.
[0069] Example 4
[0070] The method of electrochemical separation of sulfur isotopes of the present example is the same as that of Example 1, the difference is that the current applied to each electrolytic cell in steps S3-S5 is 0.8C.
[0071] Example 5
[0072] The method of electrochemical separation of sulfur isotopes of the present example is the same as that of Example 1, the difference is that the current applied to each electrolytic cell in steps S3-S5 is 0.9C.
[0073] Table 2 comparison of separation effects of Examples 1-5
[0074] Item Final 32 S purity (at%) Final 34 S purity (at%) Example 1 99.1 9.6 Example 2 99.3 9.9 Example 3 98.9 9.0 Example 4 99.0 9.5 Example 5 98.8 8.8
Claims
1. A method for electrochemical separation of sulfur isotopes, characterized in that, include S1: Prepare several electrolytic cells and divide them into three groups: the initial electrolytic cell, the collection cell, and the final electrolytic cell. 32 S electrolytic cell group and collection 34 S-electrolysis cell group, collection 34 The S electrolytic cell group includes several sets 34 S-electrolysis cells are used for graded enrichment. 34 S; collection 32 The S electrolytic cell group includes several sets 32 S-electrolysis cells are used for graded enrichment. 32 S; S2: Install the initial depletion electrode and enrichment electrode one in the initial electrolytic cell, and in all the collected... 34 Enrichment electrodes two are installed in the S electrolytic cell, and enrichment electrodes are used in all the collecting... 32 Enrichment electrodes are installed in each of the S electrolytic cells; all electrolytic cells are filled with electrolyte. S3: Perform charge-discharge cycles on a pair of electrodes in the initial electrolytic cell. 32 S is enriched on enrichment electrode one. 34 S is enriched on the depleted electrode; S4: Place the initial depleted electrodes into each set sequentially. 34 S acts as a depleted electrode in the electrolytic cell, sequentially processing the collected... 34 The initial depleted electrode and the enriched electrode of the S electrolytic cell undergo charge-discharge cycles, with each enriched electrode... 34 Inside the S electrolytic cell, 34 S is enriched on the initial depleted electrode; S5: Place the enrichment electrode into the first collection... 32 In the S electrolytic cell, it acts as a depleted electrode, and charge-discharge cycles are performed on enriched electrode one and enriched electrode three. 32 S is enriched on the third enrichment electrode; then the first enrichment electrode is... 32 The enrichment electrode of the S electrolytic cell is placed into the second collecting electrode. 32 S acts as a depleted electrode in the electrolytic cell for the second collection. 32 A pair of electrodes in an S-electrolyte cell undergoes charge-discharge cycles. 32 S is enriched on the original enrichment electrode three of the electrolytic cell; this process is repeated until the last enrichment electrode is reached. 32 S-electrolytic cell.
2. The method for electrochemical separation of sulfur isotopes according to claim 1, characterized in that, Each electrolytic cell includes a cell body and two electrode slots inside the cell body. The cell body is a cube, and the two electrode slots are respectively located on two opposite sides of the cell body. The electrode slots are vertical, with the top surface and the side facing the inside of the tank being empty, allowing the electrolyte inside the tank to enter and exit the electrode slots. The depleted electrode or enriched electrode is inserted from the top surface of the corresponding electrode slot. The two sides of the empty side of the electrode slot are equipped with baffles that protrude into the tank and are used to hold the side of the electrode in place, thus enabling repeated insertion and removal of the electrode.
3. The method for electrochemical separation of sulfur isotopes according to claim 2, characterized in that, Each electrolytic cell is equipped with a power supply. When the electrolytic cell is discharging, the positive terminal of the power supply is electrically connected to the enrichment electrode and the negative terminal is electrically connected to the depletion electrode. When the electrolytic cell is charging, the positive terminal of the power supply is electrically connected to the depletion electrode and the negative terminal is electrically connected to the enrichment electrode. The electrode slot is equipped with an electrical connection interface, which enables rapid electrode replacement and in-situ electrochemical performance calibration.
4. The method for electrochemical separation of sulfur isotopes according to claim 2, characterized in that, In step S2, enrichment electrode one is inserted into the right electrode slot of the initial electrolytic cell, and initial depletion electrode is inserted into the left electrode slot; each enrichment electrode... 34 In the S-electrolytic cell, enrichment electrodes 2 are inserted into the right electrode slots, and the left electrode slots are left empty; each enrichment electrode... 32 In the S-electrolysis cell, enrichment electrodes 3 are inserted into the right electrode slots, while the left electrode slots are left empty.
5. The method for electrochemical separation of sulfur isotopes according to claim 1, characterized in that, The distance between the depleted electrode and the enriched electrode in the electrolytic cell is 0.2-2.0 mm, and the current in steps S3-S5 is 0.05-0.8 C.
6. The method for electrochemical separation of sulfur isotopes according to claim 1, characterized in that, In step S3, the power supply of the initial electrolytic cell performs several charging and discharging processes on the enrichment electrode and the initial depletion electrode. 32 S is enriched at the enrichment electrode and simultaneously depleted at the initial depletion electrode; this is the first stage. 32 S enrichment; 34 S is enriched on the depleted electrode, and correspondingly depleted on the enriched electrode; this is the first stage. 34 S enrichment was achieved, enabling the initial separation of sulfur isotopes.
7. The method for electrochemical separation of sulfur isotopes according to claim 4, characterized in that, In step S4, the initial depleted electrode serves as the material input terminal, and the first collection is inserted. 34 The left electrode slot of the S electrolytic cell acts as a depleted electrode, undergoing several charging and discharging processes together with the original enriching electrode. The electrolyte... 34 S is enriched on the initially depleted electrode; this is secondary. 34 S enrichment; Then insert the initial depleted electrode into the second set. 34 The left electrode slot of the S electrolytic cell acts as a depleted electrode, undergoing several charging and discharging processes together with the original enriching electrode. The electrolyte... 34 S remains enriched on the initially depleted electrode; this is the third stage. 34 S enrichment; This process is repeated until the initial depleted electrode is in the last set. 34 Completed in the S electrolytic cell 34 S enrichment, where the initial depleted electrode is the product output terminal, can achieve the target. 34 S purity.
8. The method for electrochemical separation of sulfur isotopes according to claim 4, characterized in that, In step S5, the enrichment electrode one serves as the material input end, and the first enrichment electrode is inserted. 32 The left electrode slot of the S electrolytic cell acts as a depleted electrode, undergoing several charge-discharge cycles together with the original enrichment electrode. The electrolyte and the enrichment electrode... 32 S is enriched on the third enrichment electrode, which is a secondary enrichment. 32 S enrichment; Then the enrichment electrode three is inserted into the second collection. 32 The left electrode slot of the S electrolytic cell acts as a depleted electrode, undergoing several charge-discharge cycles together with the original enriched electrode. The electrolyte and the depleted electrode... 32 S in the second episode 32 The enrichment electrode of the S electrolytic cell is enriched on three levels, which is a three-stage process. 32 S enrichment; This process is repeated until the last episode. 32 Completed in the S electrolytic cell 32 S-enrichment, the last set 32 The original enrichment electrode three of the S electrolytic cell is the product output terminal, which can achieve the target. 32 S purity.