Method for preparing sodium ion battery positive electrode material by recycling waste vanadium tailings
阅读说明：本技术 一种回收废弃钒尾渣制备钠离子电池正极材料的方法 (Method for preparing sodium ion battery positive electrode material by recycling waste vanadium tailings ) 是由 欧星 苏石临 叶隆 张宝 张佳峰 于 2021-01-22 设计创作，主要内容包括：一种回收废弃钒尾渣制备钠离子电池正极材料的方法。本发明以废弃钒渣为原料,经过钠化焙烧—水浸法获得钒酸钠(NaVO-3)溶液,然后利用NaVO-3溶液制备钠离子电池正极材料磷酸钒钠(Na-3V-2(PO-4)-3)。其制备方法分为废料回收和Na-3V-2(PO-4)-3正极材料制备两步,第一步：将钒渣与钠源添加剂充分混合均匀,然后在焙烧炉中经过焙烧后通过水浸出获得NaVO-3溶液,第二步：采用补充钠源、磷源和NaVO-3溶液加入柠檬酸溶液中生成溶胶,然后将溶胶干燥得到凝胶,将凝胶热处理即得到所述正极材料Na-3V-2(PO-4)-3。利用废弃钒渣直接合成钠离子电池正极材料避免多金属分步分离回收,缩短了工艺流程,操作简单,降低成本,提升了回收再生产品的价值,而且用钒渣回收所得原料制备Na-3V-2(PO-4)-3材料具有良好的倍率性能和优异的循环稳定性。(A method for preparing a sodium-ion battery anode material by recycling waste vanadium tailings. The invention takes waste vanadium slag as raw material, and sodium vanadate (NaVO) is obtained by a sodium roasting-water leaching method 3 ) Solution, then using NaVO 3 Preparation of sodium ion battery anode material vanadium sodium phosphate (Na) by solution 3 V 2 (PO 4 ) 3 ). The preparation method comprises waste recovery and Na 3 V 2 (PO 4 ) 3 The preparation method comprises two steps of preparing the anode material, wherein the first step comprises the following steps: vanadium slag and sodium source additive are fully and uniformly mixed, and then NaVO is obtained by leaching through water after roasting in a roasting furnace 3 Solution, second step: adopts the supplement of a sodium source, a phosphorus source and NaVO 3 Adding the solution into citric acid solution to generate sol, drying the sol to obtain gel, and heat treating the gelObtaining the positive electrode material Na 3 V 2 (PO 4 ) 3 . The method for directly synthesizing the positive electrode material of the sodium-ion battery by utilizing the waste vanadium slag avoids multi-metal step separation and recovery, shortens the process flow, is simple to operate, reduces the cost, improves the value of recovered and regenerated products, and prepares Na by recovering the obtained raw material from the vanadium slag 3 V 2 (PO 4 ) 3 The material has good rate performance and excellent cycling stability.)
1. The recycling wasteThe method for preparing the sodium-ion battery anode material by using the vanadium tailings is characterized by recycling the waste vanadium slag and Na3V2(PO4)3The preparation of the anode material comprises two steps.
2. The positive electrode material Na for sodium-ion batteries according to claim 13V2(PO4)3The preparation method is characterized in that the recovery of the waste vanadium slag comprises the following steps:
(1) ball-milling the waste vanadium slag, and then sieving to obtain vanadium slag powder; taking a proper amount of vanadium slag powder and uniformly mixing with a sodium source additive to obtain a pretreatment material;
(2) roasting the pretreated material obtained in the step (1) according to a certain mode to obtain a roasted material; then fully leaching the roasted material by deionized water and filtering to obtain NaVO3And (3) solution.
3. The positive electrode material Na for sodium-ion batteries according to claim 13V2(PO4)3The method for preparing (1) is characterized in that,
Na3V2(PO4)3the preparation method of the cathode material comprises the following steps:
(1) NaVO is mixed according to a certain proportion3Adding the solution, the phosphorus source and the supplementary sodium source into the solvent, and uniformly stirring and mixing the solution;
(2) adding a certain amount of citric acid into the mixed solution obtained in the step (1), heating to 80-90 ℃, and continuously stirring for 1.5-3 h to obtain uniform sol;
(3) and fully drying the sol obtained in the second step to obtain dry gel, and grinding the dry gel into powder. Then the obtained powder is subjected to heat treatment according to a certain mode to obtain the positive electrode material Na of the sodium-ion battery3V2(PO4)3。
4. The positive electrode material Na for sodium-ion batteries according to claim 23V2(PO4)3The preparation method is characterized in that the particle size of the vanadium slag obtained by sieving in the step (1) is 80-50 μm;the mass ratio of the sodium source additive to the vanadium slag is 0.1-5: 1; the sodium source additive is one or more of sodium hydroxide, sodium acetate, sodium nitrate, sodium sulfate and sodium carbonate.
5. The positive electrode material Na for sodium-ion batteries according to claim 23V2(PO4)3The preparation method is characterized in that the roasting treatment procedure in the step (2) is to keep the temperature at 600-800 ℃ for 0.5-8 hours.
6. The positive electrode material Na for sodium-ion batteries according to claim 33V2(PO4)3The preparation method is characterized in that in the step (1), the mass ratio of sodium metal ions, vanadium metal ions and phosphate ions is 3:2:3, and the concentration of sodium ions in the mixed solution is 0.3-1 mol/L.
7. The positive electrode material Na for sodium-ion batteries according to claim 33V2(PO4)3The sodium source supplemented in the step (1) is one or more of sodium acetate, sodium nitrate, sodium sulfate and sodium carbonate; the phosphorus source is one or more of phosphoric acid, ammonium dihydrogen phosphate and sodium phosphate.
8. The positive electrode material Na for sodium-ion batteries according to claim 33V2(PO4)3The preparation method is characterized in that the mixed solution solvent in the step (1) is one or more of deionized water, ethanol and glycol.
9. The positive electrode material Na for sodium-ion batteries according to claim 33V2(PO4)3The method for producing (1) is characterized in that the amount ratio of citric acid to the metal ion in the mixed solution in the step (2) is 0.5 to 3.
10. The positive electrode material Na for sodium-ion batteries according to claim 33V2(PO4)3The preparation method is characterized in that the preparation temperature of the xerogel in the step (3) is 80-130 ℃, the segmented heat treatment procedure is that the temperature is kept at 350-650 ℃ for 4-8 hours, and then kept at 650-850 ℃ for 8-16 hours; and (4) the atmosphere environment of the heat treatment in the step (3) is argon.
Technical Field
The invention belongs to the field of preparation of anode materials by recycling waste vanadium slag, and particularly relates to a sodium-ion battery anode material Na3V2(PO4)3And a method for preparing the same.
Background
Vanadium is an important rare metal with strategic significance, is widely applied to the fields of metallurgy, batteries, nuclear materials, aerospace, energy sources and the like, has stable chemical property, is not oxidized at normal temperature, has better corrosion resistance to air, saline water, dilute acid and alkali, and has high strength, high hardness and high melting point. However, the vanadium extraction tailings produced in the existing vanadium smelting process have high vanadium content, are rich in a large number of valuable elements such as Mn, Ti, Cr, Al and the like, and have high comprehensive utilization value. The waste vanadium tailings are used as secondary resources to recover vanadium, so that the method not only can bring unusual economic and environmental benefits, but also has important significance for recycling resources.
In addition, with the rapid development of lithium ion batteries, people demand increasingly, and lithium resources are continuously consumed, so that the development of future lithium ion batteries is severely limited by the limited lithium resources. Sodium in the same main group and with similar physical and chemical properties with lithium has abundant global reserves, low cost and wide availability, and sodium ion batteries are increasingly noticed by researchers. For the present research, the sodium ion positive electrode material mainly includes polyanion, transition metal oxide, and other materials (prussian blue, organic molecules, polymers, and the like). Since the polyanion compound has high safety and excellent properties such as high reversible cycle performance, etc., it is widely studied by academia.
This patent is from environmental protection, resource cyclic utilization and new forms of energy development angle, retrieve abandonment vanadium tailings and sodium ion battery polyanion compound cathode material effectively combine, develop from abandonment vanadium tailings to the effective technology of sodium ion battery cathode material, avoided the multi-metal to separate the recovery step by step with the direct synthetic sodium ion battery cathode material of abandonment vanadium slag, shortened process flow, easy operation, reduce cost has promoted the value of retrieving the regeneration product.
The patent discloses a method for preparing a positive electrode material of a sodium-ion battery by recycling waste vanadium tailings, wherein the structural formula of the positive electrode material is Na3V2(PO4)3The cathode material is prepared by a sol-gel method, has ultrahigh rate performance and ultra-long cycle life, and has better capacity retention capacity under high current rate, so that the cathode material has quite excellent electrochemical performance.
Disclosure of Invention
The technical problem solved by the invention is as follows: the invention overcomes the defects of the prior art, and provides a method for preparing a sodium-ion battery anode material by recycling vanadium slag3V2(PO4)3The raw material is prepared into NaVO by a sodium roasting-water leaching method3Then preparing the positive electrode material Na of the sodium-ion battery by adopting a sol-gel method3V2(PO4)3The preparation process is simplified, the raw materials are in one step, the process flow is shortened, the multi-metal is prevented from being separated and recovered step by step, the value of recovered and regenerated products is effectively improved, and the anode material prepared from the recovered metals has excellent cycle stability and rate capability.
The technical scheme adopted by the invention for solving the technical problems is as follows:
the positive electrode material Na of the sodium-ion battery3V2(PO4)3The preparation method comprises two parts: recovery of waste vanadium tailings and Na3V2(PO4)3And preparing the anode material.
Preferably, the waste vanadium tailings recovery process comprises the following specific steps:
(1) ball-milling the waste vanadium tailings, and then sieving to obtain vanadium slag powder; taking a proper amount of vanadium slag powder and uniformly mixing with a sodium source additive to obtain a pretreatment material;
(2) pretreating the obtained in the step (1)Roasting the material according to a certain mode to obtain a roasted material; then fully leaching the roasted material by deionized water and filtering to obtain NaVO3And (3) solution.
Preferably, the particle size of the vanadium slag obtained by sieving is 75-60 mu m;
preferably, the mass ratio of the sodium source additive to the vanadium slag is 1-3: 1;
preferably, the sodium source additive is one or more of sodium hydroxide, sodium acetate, sodium nitrate, sodium sulfate and sodium carbonate;
preferably, the roasting treatment procedure is that the temperature is kept at 650-750 ℃ for 2-6 hours;
preferably, the Na3V2(PO4)3The preparation process of the cathode material comprises the following specific steps:
(1) NaVO is mixed according to a certain proportion3Adding the solution, the phosphorus source and the supplementary sodium source into the solvent, and uniformly stirring and mixing the solution;
(2) adding a certain amount of citric acid into the mixed solution obtained in the step (1), heating to 80-90 ℃, and continuously stirring for 1.5-3 h to obtain uniform sol;
(3) and (3) fully drying the sol obtained in the step (2) to obtain dry gel, and grinding the dry gel into powder. Then the obtained powder is subjected to heat treatment according to a certain mode to obtain the positive electrode material Na of the sodium-ion battery3V2(PO4)3。
Preferably, in the preparation process of the cathode material, the mass ratio of sodium metal ions, vanadium metal ions and phosphate ions is 3:2:3, and the concentration of sodium ions in the mixed solution is 0.3-1 mol/L.
Preferably, the supplementary sodium source in the preparation process of the cathode material is one or more of sodium acetate, sodium nitrate, sodium sulfate and sodium carbonate;
preferably, in the preparation process of the cathode material, the phosphorus source is one or more of phosphoric acid, ammonium dihydrogen phosphate and sodium phosphate;
preferably, the mixed solution solvent in the preparation process of the cathode material is one or more of deionized water, ethanol and ethylene glycol;
preferably, the amount ratio of the citric acid to the metal ion in the mixed solution in the preparation process of the cathode material is 0.5-3, preferably 1-2;
preferably, the preparation temperature of the dry gel in the preparation process of the cathode material is 80-130 ℃, and preferably 110-120 ℃;
preferably, the step of the heat treatment process in the preparation process of the anode material is to keep the temperature at 350-650 ℃ for 4-8 hours, then keep the temperature at 650-850 ℃ for 8-16 hours, preferably to keep the temperature at 350-;
preferably, the heat treatment atmosphere in the preparation process of the cathode material is argon.
The invention has the beneficial effects that:
(1) the invention provides a strategy for synthesizing a sodium-ion battery anode material by using waste vanadium tailings, which shortens the process flow, improves the utilization rate of valuable metals and avoids metal loss caused by overlong process flow. Meanwhile, a new idea is provided for treating harmful wastes, and the environment protection and the efficient and comprehensive utilization of resources are realized.
(2) The recycled raw materials are utilized to synthesize the sodium ion battery anode material through a sol-gel method, and the anode material has the characteristic of good cycle performance and is a novel environment-friendly energy storage sodium ion anode material.
(3) The preparation method provided by the invention has the advantages of simple process, low cost, stable performance and excellent electrochemical performance.
Drawings
FIG. 1 shows a positive electrode material Na for a sodium-ion battery prepared in example 1 of the present invention3V2(PO4)3XRD pattern of (a);
FIG. 2 shows the positive electrode material Na of the Na-ion battery prepared in example 1 of the present invention3V2(PO4)3A TEM image of (B);
Detailed Description
The present invention will be further described with reference to the following examples and the accompanying drawings.
Example 1
(1) The waste vanadium tailingsBall milling, and then sieving to obtain vanadium slag powder with the particle size of 60 mu m; and (3) uniformly mixing a proper amount of vanadium slag powder and sodium chloride to obtain the pretreatment material. Then roasting the obtained pretreatment material for 2 hours at 700 ℃ to obtain a roasted material, fully leaching the roasted material by deionized water, and filtering to obtain NaVO with the concentration of 0.4mol/L3And (3) solution.
(2) According to Na, V and PO4Measuring NaVO according to the proportion of 3:2:33100ml of the solution is weighed, 1.0706g of sodium carbonate and 7.0427g of ammonium dihydrogen phosphate are added and dissolved in NaVO3Adding deionized neutral water into the solution until the volume is 200mL, stirring the solution to fully dissolve the deionized neutral water, weighing 2.112g of citric acid, adding the citric acid into the mixed solution, and continuously stirring the solution in a water bath kettle at the temperature of 80 ℃ until the water is volatilized to form sol;
(2) drying the sol in a 120 ℃ oven, grinding into powder, calcining in a tube furnace filled with argon, preserving heat at 380 ℃ for 4 hours, preserving heat at 700 ℃ for 10 hours, and naturally cooling to obtain Na3V2(PO4)3A positive electrode material;
weighing 0.08g of the prepared product, 0.01g of acetylene black (conductive agent) and 0.01g of PVDF (HSV900, binder), fully grinding, adding 0.7mL of NMP for dispersing and mixing, uniformly mixing, pulling slurry on an aluminum foil for flaking, drying at 120 ℃ in vacuum, cutting into circular sheets with the diameter of 12mm, assembling in a glove box in argon atmosphere, taking a metal sodium sheet as a counter electrode, and taking 1M NaClO4The solution (EC solvent: FEC with the DMC volume ratio of 1: 15%) is used as electrolyte, and glass fiber (Grade GF/F) is used as a diaphragm to assemble the CR2032 type button cell.
The product of this example was analyzed by X-ray powder diffraction, and the result is shown in FIG. 1, which shows that Na was synthesized3V2(PO4)3The positive electrode material is a single phase, which is typically diamond-shaped.
The scanning electron microscope showed that the product of this example was fine particles of about 500nm as shown in FIG. 2.
Performing electrochemical test, and performing constant voltage charge and discharge test at 25 ℃ and 1C multiplying power of 2.0-4.0V to obtain the product with the first discharge capacity112.7mA h g～1. Performing constant-voltage charge and discharge test at 25 deg.C and 0.5C rate in 2.0-4.0V interval, and the specific charge capacity after 1000 cycles is 110.9mA hr g～1。
Example 2
(1) Ball-milling the waste vanadium tailings, and then sieving to obtain vanadium slag powder with the particle size of 60 mu m; and (3) uniformly mixing a proper amount of vanadium slag powder and sodium chloride to obtain the pretreatment material. Then roasting the obtained pretreatment material for 1 hour at 750 ℃ to obtain a roasted material, fully leaching the roasted material by deionized water, and filtering to obtain NaVO with the concentration of 0.4mol/L3And (3) solution.
(2) According to Na, V and PO4Measuring NaVO according to the proportion of 3:2:33100ml of the solution, 1.7345g of sodium nitrate and 8.0036g of diammonium phosphate are added and dissolved in NaVO3Adding deionized neutral water into the solution until the volume is 200mL, stirring the solution to fully dissolve the deionized neutral water, weighing 2.112g of citric acid, adding the citric acid into the mixed solution, and continuously stirring the solution in a water bath kettle at the temperature of 80 ℃ until the water is volatilized to form sol;
(2) drying the sol in a 120 ℃ oven, grinding into powder, calcining in a tube furnace filled with argon, preserving heat at 380 ℃ for 4 hours, preserving heat at 700 ℃ for 10 hours, and naturally cooling to obtain Na3V2(PO4)3A positive electrode material;
weighing 0.08g of the prepared product, 0.01g of acetylene black (conductive agent) and 0.01g of PVDF (HSV900, binder), fully grinding, adding 0.7mL of NMP for dispersing and mixing, uniformly mixing, pulling slurry on an aluminum foil for flaking, drying at 120 ℃ in vacuum, cutting into circular sheets with the diameter of 12mm, assembling in a glove box in argon atmosphere, taking a metal sodium sheet as a counter electrode, and taking 1M NaClO4The solution (EC solvent: FEC with the DMC volume ratio of 1: 15%) is used as electrolyte, and glass fiber (Grade GF/F) is used as a diaphragm to assemble the CR2032 type button cell. Performing electrochemical test, wherein when constant-voltage charge and discharge test is performed at 25 ℃ and under the condition that the multiplying power of 1C is 2.0-4.0V, the first discharge capacity of the product is 113.8mA h g～1. Performing constant-voltage charge and discharge test at 25 deg.C and 0.5C rate in 2.0-4.0V region, and the specific charge capacity after 1000 cycles111.4mA h g～1。
Example 3
(1) Ball-milling the waste vanadium tailings, and then sieving to obtain vanadium slag powder with the particle size of 60 mu m; and (3) uniformly mixing a proper amount of vanadium slag powder and sodium chloride to obtain the pretreatment material. Then roasting the obtained pretreatment material for 2 hours at 720 ℃ to obtain a roasted material, fully leaching the roasted material by deionized water, and filtering to obtain NaVO with the concentration of 0.4mol/L3And (3) solution.
(2) According to Na, V and PO4Measuring NaVO according to the proportion of 3:2:33100ml of the solution is weighed, 1.0706g of sodium carbonate and 7.0427g of ammonium dihydrogen phosphate are added and dissolved in NaVO3Adding deionized neutral water to 150mL, stirring to fully dissolve, weighing 3.168g of citric acid, adding into the mixed solution, and continuously stirring in a water bath kettle at 80 ℃ until water is volatilized to form sol;
(2) drying the sol in a 120 ℃ oven, grinding into powder, calcining in a tube furnace filled with argon, keeping the temperature at 400 ℃ for 4 hours, keeping the temperature at 750 ℃ for 12 hours, and naturally cooling to obtain Na3V2(PO4)3A positive electrode material;
weighing 0.08g of the prepared product, 0.01g of acetylene black (conductive agent) and 0.01g of PVDF (HSV900, binder), fully grinding, adding 0.6mL of NMP for dispersing and mixing, uniformly mixing, pulling slurry on an aluminum foil for flaking, drying at 120 ℃ in vacuum, cutting into circular sheets with the diameter of 12mm, assembling in a glove box in argon atmosphere, taking a metal sodium sheet as a counter electrode, and taking 1M NaClO4The solution (EC solvent: FEC with the DMC volume ratio of 1: 15%) is used as electrolyte, and glass fiber (Grade GF/F) is used as a diaphragm to assemble the CR2032 type button cell. Performing electrochemical test, wherein when constant-voltage charge and discharge test is performed at 25 ℃ and under the condition that the multiplying power of 1C is 2.0-4.0V, the first discharge capacity of the product is 110.7mA h g～1. Performing constant-voltage charge and discharge test at 25 deg.C and 0.5C rate in 2.0-4.0V region, and the specific charge capacity after 1000 cycles is 108.6mA hr g～1。