Nothing Special   »   [go: up one dir, main page]

CN114212765A - Method for recycling lithium iron phosphorus component in waste lithium iron phosphate powder - Google Patents

Method for recycling lithium iron phosphorus component in waste lithium iron phosphate powder Download PDF

Info

Publication number
CN114212765A
CN114212765A CN202210015252.6A CN202210015252A CN114212765A CN 114212765 A CN114212765 A CN 114212765A CN 202210015252 A CN202210015252 A CN 202210015252A CN 114212765 A CN114212765 A CN 114212765A
Authority
CN
China
Prior art keywords
lithium iron
lithium
iron phosphate
waste
powder
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Granted
Application number
CN202210015252.6A
Other languages
Chinese (zh)
Other versions
CN114212765B (en
Inventor
曹雁冰
胡国荣
彭忠东
杜柯
龚亦帆
吴家辉
张旭东
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Central South University
Original Assignee
Central South University
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Central South University filed Critical Central South University
Priority to CN202210015252.6A priority Critical patent/CN114212765B/en
Publication of CN114212765A publication Critical patent/CN114212765A/en
Application granted granted Critical
Publication of CN114212765B publication Critical patent/CN114212765B/en
Active legal-status Critical Current
Anticipated expiration legal-status Critical

Links

Images

Classifications

    • CCHEMISTRY; METALLURGY
    • C01INORGANIC CHEMISTRY
    • C01BNON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
    • C01B25/00Phosphorus; Compounds thereof
    • C01B25/16Oxyacids of phosphorus; Salts thereof
    • C01B25/26Phosphates
    • C01B25/45Phosphates containing plural metal, or metal and ammonium
    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01MPROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M10/00Secondary cells; Manufacture thereof
    • H01M10/05Accumulators with non-aqueous electrolyte
    • H01M10/052Li-accumulators
    • H01M10/0525Rocking-chair batteries, i.e. batteries with lithium insertion or intercalation in both electrodes; Lithium-ion batteries
    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01MPROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M10/00Secondary cells; Manufacture thereof
    • H01M10/54Reclaiming serviceable parts of waste accumulators
    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01MPROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M4/00Electrodes
    • H01M4/02Electrodes composed of, or comprising, active material
    • H01M4/36Selection of substances as active materials, active masses, active liquids
    • H01M4/58Selection of substances as active materials, active masses, active liquids of inorganic compounds other than oxides or hydroxides, e.g. sulfides, selenides, tellurides, halogenides or LiCoFy; of polyanionic structures, e.g. phosphates, silicates or borates
    • H01M4/5825Oxygenated metallic salts or polyanionic structures, e.g. borates, phosphates, silicates, olivines
    • CCHEMISTRY; METALLURGY
    • C01INORGANIC CHEMISTRY
    • C01PINDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
    • C01P2002/00Crystal-structural characteristics
    • C01P2002/70Crystal-structural characteristics defined by measured X-ray, neutron or electron diffraction data
    • C01P2002/72Crystal-structural characteristics defined by measured X-ray, neutron or electron diffraction data by d-values or two theta-values, e.g. as X-ray diagram
    • CCHEMISTRY; METALLURGY
    • C01INORGANIC CHEMISTRY
    • C01PINDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
    • C01P2004/00Particle morphology
    • C01P2004/01Particle morphology depicted by an image
    • C01P2004/03Particle morphology depicted by an image obtained by SEM
    • CCHEMISTRY; METALLURGY
    • C01INORGANIC CHEMISTRY
    • C01PINDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
    • C01P2004/00Particle morphology
    • C01P2004/30Particle morphology extending in three dimensions
    • C01P2004/32Spheres
    • CCHEMISTRY; METALLURGY
    • C01INORGANIC CHEMISTRY
    • C01PINDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
    • C01P2004/00Particle morphology
    • C01P2004/60Particles characterised by their size
    • C01P2004/61Micrometer sized, i.e. from 1-100 micrometer
    • CCHEMISTRY; METALLURGY
    • C01INORGANIC CHEMISTRY
    • C01PINDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
    • C01P2006/00Physical properties of inorganic compounds
    • C01P2006/40Electric properties
    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01MPROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M4/00Electrodes
    • H01M4/02Electrodes composed of, or comprising, active material
    • H01M2004/026Electrodes composed of, or comprising, active material characterised by the polarity
    • H01M2004/028Positive electrodes
    • YGENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02EREDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
    • Y02E60/00Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
    • Y02E60/10Energy storage using batteries
    • YGENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02WCLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO WASTEWATER TREATMENT OR WASTE MANAGEMENT
    • Y02W30/00Technologies for solid waste management
    • Y02W30/50Reuse, recycling or recovery technologies
    • Y02W30/84Recycling of batteries or fuel cells

Landscapes

  • Chemical & Material Sciences (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Engineering & Computer Science (AREA)
  • Electrochemistry (AREA)
  • General Chemical & Material Sciences (AREA)
  • Organic Chemistry (AREA)
  • Manufacturing & Machinery (AREA)
  • Inorganic Chemistry (AREA)
  • Materials Engineering (AREA)
  • Crystallography & Structural Chemistry (AREA)
  • Manufacture And Refinement Of Metals (AREA)
  • Processing Of Solid Wastes (AREA)
  • Battery Electrode And Active Subsutance (AREA)

Abstract

The invention belongs to the technical field of lithium ion battery recycling and regeneration, and particularly relates to a method for recycling lithium iron phosphorus components in waste lithium iron phosphate powder. The invention pre-removes aluminum from waste lithium iron phosphate powder, uses phosphoric acid and reductive organic acid to leach and leach jointly, uses different iron compounds to prepare precursor slurry by mechanical activation through inhibiting oxidation, and uses sand grinding-spray drying to prepare the lithium iron phosphate precursor in cooperation with the purified lithium-rich slurry. The technical process of the invention is matched with the production process of mainstream lithium iron phosphate, no wastewater is generated in the whole process, the leaching reagent is conventional, no additional redox agent is required to be added, the combined use of multiple iron sources is favorable for improving the viscosity and the particle size of the precursor slurry, and the electrochemical performance of the recycled product is improved. The whole process is simple and has atom economy, the high-efficiency recovery and regeneration of three elements of lithium, iron and phosphorus in the high-impurity lithium iron phosphate waste powder are realized, and the method is suitable for industrial production.

Description

Method for recycling lithium iron phosphorus component in waste lithium iron phosphate powder
Technical Field
The invention belongs to the field of lithium ion secondary battery recovery, and particularly relates to a method for recycling lithium iron phosphorus components in waste lithium iron phosphate powder.
Background
In recent years, the fire heat of the lithium iron phosphate positive electrode material market also drives the development of the whole lithium iron phosphate recovery market, but in the past years, because the whole lithium iron phosphate recovery chain is not paid attention to domestically, a large amount of lithium iron phosphate positive electrode powder is accumulated. Most of the raw materials of the powder have unclear sources, non-uniform components and high impurity content, and the traditional pyrogenic process repair at present is difficult to make the raw materials reach the physicochemical indexes of battery-grade lithium iron phosphate. Along with the rising of the price of the raw materials in the market of the upstream materials, how to treat the accumulated high-impurity lithium iron phosphate waste powder and efficiently recycle three valuable elements of lithium, iron and phosphorus in the lithium iron phosphate waste powder becomes one of the primary problems of promoting the ecological balance of the whole lithium ion secondary battery
At present, the recovery of the lithium iron phosphate anode material is mainly direct repair by a pyrogenic process and recovery by a wet process. Direct repair by a pyrogenic process is the simplest and most convenient method, but the requirement on raw materials is high, impurities of the raw materials are difficult to select and separate effectively, and recycled pole pieces and non-recycled high-impurity disassembled powder are difficult to treat, for example, CN 113582153A introduces a regenerated and repaired waste lithium iron phosphate positive material and a regeneration method thereof, but the method does not involve separation of impurities and is difficult to treat common lithium iron phosphate waste powder in the market. The wet recovery can treat most of recovered raw materials on the market, but complicated steps are difficult to avoid the generation of waste water, the recovery rate of lithium is high, but the utilization rate of iron and phosphorus is low, and most enterprises treat iron-phosphorus slag after lithium extraction as waste slag at low price. For example, CN 113603119A introduces a method for recovering lithium from waste lithium iron phosphate materials, but does not treat the phosphorus-iron slag after lithium extraction, and the total recovery rate is not high. For example, CN 110098442A introduces a method for regenerating lithium iron phosphate by using a leaching-spray drying-solid phase method, but impurities in lithium iron phosphate are not treated, strong acids such as sulfuric acid and hydrochloric acid are used as leaching agents, and simultaneously, spray drying is directly performed in a solution form, so that equipment is corroded, and impurity anions are introduced into products.
Disclosure of Invention
Aiming at the problems of low overall recovery rate of lithium iron phosphorus, difficult treatment of impurities, large acid and alkali dosage, large wastewater generation amount and the like in the existing waste lithium iron phosphate recovery technology, the method has the advantages of simple process, realization of closed treatment of the whole process flow, matching with the existing lithium iron phosphate production process and efficient cyclic regeneration of the lithium iron phosphorus component. The method has the advantages that the impurity separation effect is excellent, water in the whole process is finally converted into steam in spray drying, no waste water is discharged, the auxiliary material cost is low, all-element economic benefit and high utilization rate are achieved, the overall recovery rate of three main elements lithium iron phosphorus is high, and the electrochemical performance of the prepared lithium iron phosphate material is excellent.
In order to achieve the above-mentioned objects,
the invention provides the following technical scheme:
a method for recovering and regenerating lithium iron phosphorus components in waste lithium iron phosphate powder comprises the following steps:
step (1): calcining the obtained disassembled waste lithium iron phosphate powder under the protection of protective atmosphere;
step (2): pre-removing aluminum from the lithium iron phosphate waste powder obtained in the step (1) in a LiOH solution to obtain aluminum-removed waste powder and an aluminum-containing lithium-rich solution;
and (3): introducing carbon dioxide into the aluminum-containing lithium-rich solution to precipitate aluminum hydroxide, and performing solid-liquid separation to obtain a purified lithium-rich solution;
and (4): mixing and leaching the aluminum-removed waste powder by adopting phosphoric acid and reducing organic acid; filtering to obtain leachate and filter residue.
And (5): leaching the solution obtained in the step (4)Iron powder is added into the solution, mechanical activation is carried out, and conversion reaction is carried out to form Fe3(PO4)2Sizing agent;
and (6): supplementing an iron source into the slurry to adjust the molar ratio of iron to phosphorus to be 1: 1-1: 1.03, and supplementing a carbon source for coarse grinding;
and (7): mixing the slurry obtained by coarse grinding in the step (6) by using the lithium-rich solution obtained in the step (3), and supplementing a lithium source to adjust the molar ratio of the three elements of lithium, iron and phosphorus in the slurry to 1-1.05: 1: 1-1.03; then obtaining a lithium iron phosphate precursor powder material by sanding and spray drying;
and (8): and sintering the lithium iron phosphate precursor powder material in a protective atmosphere to obtain the lithium iron phosphate positive active material.
The existing lithium iron phosphate recovery process has complicated routes which are difficult to unify, the waste lithium iron phosphate powder with high impurity content is difficult to directly change from the waste powder to the anode material, most of the recovery processes recover the waste lithium iron phosphate powder as raw materials (such as iron phosphate and lithium carbonate) to synthesize the lithium iron phosphate, and the problems of poor electrochemical performance of the regenerated product, difficult treatment of three wastes and the like are faced. According to the invention, through research, the lithium iron phosphate waste powder is subjected to aluminum pre-removal, then is leached by combining phosphoric acid and reductive organic acid, is subjected to oxidation inhibition, is prepared into precursor slurry by using different iron compounds through mechanical activation, and is subjected to sand grinding-spray drying to prepare the lithium iron phosphate precursor in cooperation with the purified lithium-rich slurry. The method has the advantages that the recovery and reutilization of three components of lithium, iron and phosphorus in the waste lithium iron phosphate powder and the high-selectivity separation of impurities can be efficiently realized, the participation of different iron compounds is beneficial to improving the electrochemical performance and physicochemical indexes of the recovered product, and the method is simple in process, can be fully suitable for the upstream market of the waste lithium iron phosphate powder, and can realize real industrial amplification production.
In the invention, the waste lithium iron phosphate powder is a black powder material obtained by disassembling and recycling waste lithium iron phosphate batteries;
in the invention, the waste lithium iron phosphate powder contains a waste lithium iron phosphate anode material and at least one of a negative electrode material, a binder, a current collector and an electrolyte. The impurities are mainly graphite and copper elements brought by a negative electrode, aluminum elements brought by a current collector and aluminum compounds coated on the edge of the pole piece.
In the invention, in the waste lithium iron phosphate powder, Li is more than or equal to 3.5% and less than or equal to 4.3%, Fe is more than or equal to 32.5% and less than or equal to 35.5%, and P is more than or equal to 18.5% and less than or equal to 19.5%. The allowable amount of impurities in the waste powder is not particularly required, for example, the content of Cu element is less than or equal to 1 wt.%, the content of Al element is less than or equal to 2 wt.%, and the content of carbon element is less than or equal to 15 wt.%. In consideration of economic benefits, the impurity content of the waste lithium iron phosphate powder can be controlled to be 0.05-1.5% of Cu, 0.5-1.5% of Al and 7-15% of carbon.
According to the technical scheme, the lithium iron phosphate waste powder is subjected to heat treatment in a protective atmosphere, so that the binder is inactivated and separated at a high temperature, the surface wettability of particles in the subsequent leaching process is improved, and the leaching rate of lithium iron phosphorus is improved. Simultaneously reacting impurity metal Al with residual electrolyte to form AlF3
Preferably, the calcining temperature is 400-600 ℃.
Preferably, the calcination time is 4 to 8 hours.
According to the invention, the lithium hydroxide solution is adopted for pretreatment, so that the effective stripping effect on residual aluminum impurities can be realized.
Preferably, the concentration of lithium hydroxide is 0.15 to 1 mol/L; further preferably 0.5 to 8 mol/L.
Preferably, the liquid-solid ratio in the aluminum removing process is 5-8: 1.
preferably, the temperature is 40-60 ℃.
Preferably, the time is 30 to 90 minutes.
In the invention, the phosphoric acid and the reducing organic acid are used for combined leaching, so that the oxidation and sedimentation of iron ions in the leaching process are reduced, impurities are reduced from entering the precursor solution, the improvement of the viscosity of the slurry in the leaching process is facilitated, and the leaching rate is improved; the separation effect on impurities is obvious.
In the invention, the concentration of phosphoric acid in the leaching process (referring to the initial concentration of phosphoric acid in a leaching system) is 1.6-4.4M in a preferable range.
In the invention, the concentration of the organic acid in the leaching process (referring to the initial concentration of the organic acid in the leaching system) is 0.05-0.45M in a preferable range.
Preferably, the liquid-solid ratio in the leaching process is 4-8: 1
Preferably, the leaching time is 3-5 h.
Preferably, the leaching temperature is 50-60 ℃.
The invention adopts mechanical activation, which is high-energy mechanical activation in ball milling. The lithium iron phosphorus in the precursor liquid is settled by ball milling, different iron sources are supplemented, the spray drying segregation degree of the slurry is favorably reduced, the phase and the dispersion form of the phase are adjusted, and the electrochemical performance and the compaction density of a target product are favorably improved.
Preferably, the rotation speed of ball milling activation is 350 rmp-500 rmp;
preferably, the ball milling time is 4-6 h.
The iron source is at least one of organic acid salt, carbonate and oxidation of iron; preferably ferrous oxalate, Fe2O3、Fe3O4At least one of (1).
Preferably, the carbon source is an organic carbon source, and the addition amount of the carbon source is 6-15% of the mass of the target product.
The invention uses the purified liquid after aluminum removal (namely the lithium-rich solution containing aluminum) as a part of lithium source and simultaneously adjusts the solid content of the slurry, and the rest lithium source adopts at least one of lithium carbonate or lithium hydroxide.
In the invention, the purified liquid after aluminum removal is used as a lithium source, which is beneficial to realizing the water balance of the whole process flow. In the invention, the traditional oxidant is not needed to be used for assisting the oxidation and precipitation, and valuable components in the waste lithium iron phosphate powder and the leaching agent and auxiliary materials in the leaching process are used as raw materials of the target product lithium iron phosphate, so that the maximization of the atom utilization rate in the true sense is realized.
In the invention, the slurry M is treated by sanding and spraying, and the whole recovery and regeneration process is in accordance with the current lithium iron phosphate production process.
Preferably, the temperature of an air inlet is 240-260 ℃, the temperature of an air outlet is 90-105 ℃ and the feeding speed is 30-50 mL/h in the spray drying stage.
Preferably, the calcining temperature in the step (8) is 650-800 ℃; the time is 6-10 h.
The protective atmosphere is inert atmosphere or nitrogen; the inert atmosphere is preferably argon.
The method for efficiently recovering and regenerating the lithium iron phosphorus component in the preferable lithium iron phosphate waste powder comprises the following steps:
a) the obtained disassembled waste lithium iron phosphate powder is calcined in a closed manner under the protection of inert atmosphere, the impurity content range of the calcined product is more than or equal to 0.05 percent and less than or equal to 1.5 percent of Cu element, more than or equal to 0.5 percent and less than or equal to 1.5 percent of Al element, and more than or equal to 7 percent and less than or equal to 15 percent of carbon element;
b) pre-removing aluminum from the waste lithium iron phosphate powder by using 0.5mol/L lithium hydroxide solution, wherein the liquid-solid ratio in the aluminum removing process is 5:1, the temperature is 50 ℃, the time is 60 minutes, and the waste lithium iron phosphate powder after aluminum removal and a lithium-rich solution containing aluminum impurities are obtained after suction filtration;
c) introducing carbon dioxide into the lithium-rich solution, stirring and precipitating aluminum for 2 hours at the temperature of 60 ℃, and filtering to obtain a purified lithium-rich solution and white aluminum slag;
d) taking waste lithium iron phosphate powder containing 0.1mol of lithium iron phosphate, and leaching by mixing phosphoric acid and organic acid, wherein LiFePO is obtained4:H3PO4: the molar ratio of the organic acid is 1: 2.5: 0.15, the liquid-solid ratio in the leaching process is 4:1, the temperature is 50 ℃, the time is 3 hours, and green leaching liquid and black filter residue are obtained after filtration;
e) supplementing 0.1mol of iron powder into the leaching solution, and rotating at the speed of 400rmp for 4 hours;
f) continuously supplementing ferrous oxalate, adjusting the iron-phosphorus ratio in the system to be 1:1, supplementing starch with the mass of 8% of that of the target product as a carbon source, and continuously performing coarse grinding for 1 h;
g) mixing the coarsely ground slurry by using the lithium-rich solution obtained in the step (c), simultaneously supplementing lithium carbonate or lithium hydroxide, and adjusting the molar ratio of three elements of lithium, iron and phosphorus in the slurry to 1-1.05: 1:1 to obtain slurry M; obtaining a lithium iron phosphate precursor powder material by adopting a sand grinding-spraying method for the slurry M;
h) and (g) calcining the lithium iron phosphate precursor powder obtained in the step (g) in an inert atmosphere to obtain a lithium iron phosphate product.
The beneficial effects include:
the invention can efficiently realize the waste-free treatment and high-value utilization of the waste lithium iron phosphate powder, and can realize the waste-free or less-waste treatment in the real sense through the ring-to-ring buckling of the whole process flow and the closed circulation of the process flow. The invention lays a foundation for the surface wettability of particles, aluminum removal and improvement of the leaching rate of lithium, iron and phosphorus in the later leaching process through the initial inert sintering treatment of the process steps; in addition, through the treatment of the step of removing aluminum, aluminum impurities are removed from the lithium hydroxide solution, and the purified and impurity-removed lithium-rich solution can be used as a subsequent lithium source, so that the whole process flow can be closed. The solution after aluminum removal is soluble lithium-rich solution, and lithium exists in the form of lithium bicarbonate, so that the consistency of the whole precursor is improved, and the segregation phenomenon is reduced. And multiple iron compounds are formed during synthesis, so that the compaction density of the product is favorably improved, and the prepared lithium iron phosphate has excellent electrochemical performance and extremely high overall recovery rate, and is suitable for industrial production.
Furthermore, the invention adopts the combined leaching of phosphoric acid and reductive organic acid, thereby greatly improving the leaching rate of lithium, iron and phosphorus in the waste lithium iron phosphate powder; meanwhile, the organic acid is used as a partial carbon source of the target product lithium iron phosphate, so that the atom utilization rate of the raw materials and the auxiliary materials is greatly improved. Mechanical ball milling activation is adopted to promote phase transformation of iron components in the leaching solution, so that introduction of hydrogen peroxide in a general selective leaching process is avoided, and the cost is reduced.
The technical process of the invention is completely fit with the production process of mainstream lithium iron phosphate, no wastewater is generated in the whole process, the leaching reagent is conventional, no additional redox agent is required to be added, the combined use of multiple iron sources is favorable for improving the viscosity and the particle size of the precursor slurry, and the electrochemical performance of the recycled product is improved. The whole process is simple and has atom economy, the high-efficiency recovery and regeneration of three elements of lithium, iron and phosphorus in the high-impurity lithium iron phosphate waste powder are realized, and the method is suitable for industrial production.
Drawings
FIG. 1 is a flow chart of the whole process and a flow chart of water (taking example 1 as an example).
Fig. 2 is an XRD pattern of lithium iron phosphate recovered and regenerated in example 1.
Fig. 3 is an SEM image of lithium iron phosphate recovered and regenerated in example 1.
Fig. 4 is a graph showing cycle performance and coulombic efficiency of the lithium iron phosphate recovered and regenerated in example 1.
Fig. 5 is a different-rate charge-discharge curve of the lithium iron phosphate recovered and regenerated in example 1.
Fig. 6 is a different-rate charge-discharge curve of the lithium iron phosphate recovered and regenerated in example 2.
Fig. 7 is a different-rate charge-discharge curve of lithium iron phosphate recovered and regenerated in comparative example 1.
Detailed Description
The following are exemplary embodiments of the present invention, but it should be understood that the present invention is not limited to these embodiments.
Example 1
The lithium iron phosphate waste powder selected in the scheme comprises the following components: li element 4.1 wt.%, Fe element 34.4 wt.%, P element 18.8 wt.%, Al element 1.5 wt.%, Cu element 0.8 wt.%, C element 7 wt.%
Step (a): the obtained disassembled waste lithium iron phosphate powder is hermetically calcined for 4 hours at 550 ℃ under the protection of inert atmosphere;
step (b): pre-removing aluminum from 17.4g of waste lithium iron phosphate powder (containing 0.1mol of lithium iron phosphate) by using 0.8mol/L lithium hydroxide solution, wherein the liquid-solid ratio in the aluminum removing process is 5:1, the temperature is 50 ℃, the time is 60 minutes, and the waste lithium iron phosphate powder after aluminum removal and a lithium-rich solution containing aluminum impurities are obtained after suction filtration, wherein the lithium-rich solution is about 80 mL;
step (c): introducing carbon dioxide into the lithium-rich solution, stirring and precipitating aluminum for 2 hours at the temperature of 60 ℃, and filtering to obtain a purified lithium-rich solution and white aluminum slag;
step (d): mixing and leaching the waste lithium iron phosphate powder subjected to aluminum removal by adopting phosphoric acid and citric acid, wherein LiFePO is obtained4:H3PO4: the molar ratio of the citric acid is 1: 2.5: 0.15, leachingThe process liquid-solid ratio is 4:1, the temperature is 50 ℃, the time is 3 hours, green leaching liquid and black filter residue are obtained after filtration, the content of each element in the filter residue is detected by adopting an inductively coupled plasma spectrum generator, and the leaching rate of Li is calculated to be more than 97%, the leaching rate of Fe is calculated to be more than 96%, and the leaching rate of P is calculated to be more than 96%;
a step (e): supplementing 0.1mol of iron powder into the leaching solution, and rotating at the speed of 400rmp for 4 hours; continuously supplementing ferrous oxalate, adjusting the iron-phosphorus ratio in the system to be 1:1, supplementing starch with the mass of 8% of that of the target product as a carbon source, and continuously performing coarse grinding for 1 h;
step (f): mixing the slurry after coarse grinding by using the lithium-rich solution obtained in the step (c), adjusting the solid content to 35%, and simultaneously supplementing lithium carbonate, wherein the molar ratio of the three elements of lithium, iron and phosphorus in the slurry is adjusted to 1-1.05: 1: 1-1.03, so as to obtain a slurry M; obtaining a lithium iron phosphate precursor powder material by adopting a sand grinding-spray drying method for the slurry M;
and (g) calcining the precursor powder in an inert atmosphere at the temperature of 450 ℃ for 4h and at the temperature of 700 ℃ for 6h to obtain the black lithium iron phosphate active material.
The XRD pattern of the lithium iron phosphate recovered and regenerated in example 1 is shown in fig. 2.
An SEM spectrum of the lithium iron phosphate recovered and regenerated in example 1 is shown in fig. 3.
The lithium iron phosphate cathode material prepared in example 1, acetylene black and a binder (PVDF) were uniformly mixed in a mass ratio of 8:1:1, and then manually ground using NMP as a solvent to obtain a uniformly mixed slurry. Coating the obtained slurry on an aluminum foil, drying the aluminum foil in a vacuum oven at 100 ℃ for 6 hours, and then beating the aluminum foil into a disk-shaped pole piece with the diameter of 8 mm. The pole piece is assembled into a CR2025 button cell. And carrying out constant-current charge and discharge tests at room temperature (25 ℃) and with the limiting voltage of 2-4V. Through detection, the 1C capacity is 147.3mAh/g, the 2C capacity is 139.7mAh/g, and the 5C capacity is 120.9 mAh/g. The cycle performance and coulombic efficiency of the lithium iron phosphate prepared by recycling and regenerating in example 1 are shown in fig. 4. Fig. 5 shows different-rate charge/discharge curves of the lithium iron phosphate recovered and regenerated in example 1.
Example 2
The lithium iron phosphate waste powder selected in the scheme comprises the following components: 3.8 wt.% of Li element, 33.5 wt.% of Fe element, 18.1 wt.% of P element, 0.9 wt.% of Al element, 1 wt.% of Cu element, and 8 wt.% of C element.
Step (a): the obtained disassembled waste lithium iron phosphate powder is hermetically calcined for 4 hours at 550 ℃ under the protection of inert atmosphere;
step (b): pre-removing aluminum from 17.5g of waste lithium iron phosphate powder (containing 0.1mol of lithium iron phosphate) by using 0.5mol/L lithium hydroxide solution, wherein the liquid-solid ratio in the aluminum removing process is 6:1, the temperature is 50 ℃, the time is 60 minutes, and the waste lithium iron phosphate powder after aluminum removal and a lithium-rich solution containing aluminum impurities are obtained after suction filtration, wherein the lithium-rich solution is about 100 mL;
step (c): introducing carbon dioxide into the lithium-rich solution, stirring and precipitating aluminum for 2 hours at the temperature of 60 ℃, and filtering to obtain a purified lithium-rich solution and white aluminum slag;
step (d): mixing and leaching the waste lithium iron phosphate powder subjected to aluminum removal by adopting phosphoric acid and citric acid, wherein LiFePO is obtained4:H3PO4: the molar ratio of the citric acid is 1: 2.5: 0.2, the liquid-solid ratio in the leaching process is 4:1, the temperature is 50 ℃, the time is 3 hours, green leaching liquid and black filter residue are obtained after filtration, and through detection (the method and the apparatus are the same as the embodiment 1), the leaching rate of Li is more than 97%, the leaching rate of Fe is more than 96%, and the leaching rate of P is more than 96%;
a step (e): supplementing 0.1mol of iron powder into the leaching solution, and rotating at the speed of 400rmp for 4 hours; continuously supplementing ferric oxide, adjusting the iron-phosphorus ratio in the system to be 1:1, supplementing starch with the mass of 10% of the target product as a carbon source, and continuously coarsely grinding for 1 h;
step (f): mixing the coarsely ground slurry by using the lithium-rich solution obtained in the step (c), adjusting the solid content to 32%, and simultaneously supplementing lithium carbonate, wherein the molar ratio of the three elements of lithium, iron and phosphorus in the slurry is adjusted to 1-1.05: 1:1, so as to obtain slurry M; obtaining a lithium iron phosphate precursor powder material by adopting a sand grinding-spraying method for the slurry M;
and (g) calcining the precursor powder in an inert atmosphere at the temperature of 450 ℃ for 4h and at the temperature of 700 ℃ for 6h to obtain the black lithium iron phosphate active material.
The electrochemical performance test of the lithium iron phosphate cathode material prepared in the embodiment 2 is the same as that of the embodiment 1.
Through detection, the 1C capacity is 145.6mAh/g, the 2C capacity is 139.3mAh/g, and the 5C capacity is 121.1 mAh/g. Fig. 6 shows different-rate charge/discharge curves of the lithium iron phosphate prepared by recovery and regeneration in example 2.
Example 3
The lithium iron phosphate waste powder selected in the scheme comprises the following components: 4.1 wt.% of Li element, 34.1 wt.% of Fe element, 19.2 wt.% of P element, 0.9 wt.% of Al element, 0.3 wt.% of Cu element, and 12 wt.% of C element.
Step (a): the obtained disassembled waste lithium iron phosphate powder is hermetically calcined for 4 hours at 550 ℃ under the protection of inert atmosphere;
step (b): pre-removing aluminum from 18.2g of waste lithium iron phosphate powder (containing 0.1mol of lithium iron phosphate) by using 0.5mol/L lithium hydroxide solution, wherein the liquid-solid ratio in the aluminum removing process is 6:1, the temperature is 50 ℃, the time is 60 minutes, and the waste lithium iron phosphate powder after aluminum removal and a lithium-rich solution containing aluminum impurities are obtained after suction filtration, wherein the lithium-rich solution is about 100 mL;
step (c): introducing carbon dioxide into the lithium-rich solution, stirring and precipitating aluminum for 2 hours at the temperature of 60 ℃, and filtering to obtain a purified lithium-rich solution and white aluminum slag;
step (d): the waste lithium iron phosphate powder after aluminum removal is leached by mixing phosphoric acid and ascorbic acid, wherein LiFePO is used4:H3PO4: the molar ratio of the ascorbic acid is 1: 2.8: 0.2, the liquid-solid ratio in the leaching process is 6:1, the temperature is 60 ℃, the time is 5 hours, green leaching liquid and black filter residue are obtained after filtration, and through detection (the detection method and the detection instrument are the same as the embodiment 1), the leaching rate of Li is more than 98%, the leaching rate of Fe is more than 97%, and the leaching rate of P is more than 96%;
a step (e): supplementing 0.12mol of iron powder into the leaching solution, and rotating at the speed of 500rmp for 4 hours; continuously supplementing ferric oxide, adjusting the iron-phosphorus ratio in the system to be 1:1, supplementing starch with the mass of 10% of the target product as a carbon source, and continuously coarsely grinding for 1 h;
step (f): mixing the coarsely ground slurry by using the lithium-rich solution obtained in the step (c), adjusting the solid content to 33%, simultaneously supplementing lithium hydroxide, and adjusting the molar ratio of the three elements of lithium, iron and phosphorus in the slurry to 1-1.05: 1:1 to obtain slurry M; obtaining a lithium iron phosphate precursor powder material by adopting a sand grinding-spraying method for the slurry M;
and (g) calcining the precursor powder in an inert atmosphere at the temperature of 450 ℃ for 4h and at the temperature of 700 ℃ for 6h to obtain the black lithium iron phosphate active material.
The electrochemical performance test of the lithium iron phosphate cathode material prepared in the embodiment 3 is the same as that of the embodiment 1.
Through detection, the 1C capacity is 146.3mAh/g, the 2C capacity is 137.8mAh/g, and the 5C capacity is 119.7 mAh/g.
Comparative example 1
The difference compared with example 1 is only that the mechanical activation is carried out by adding iron powder in an amount equimolar to the amount of phosphoric acid. The method comprises the following specific steps:
step (a): the obtained disassembled waste lithium iron phosphate powder is hermetically calcined for 4 hours at 550 ℃ under the protection of inert atmosphere;
step (b): pre-removing aluminum from 17.4g of waste lithium iron phosphate powder (containing 0.1mol of lithium iron phosphate) by using 0.8mol/L lithium hydroxide solution, wherein the liquid-solid ratio in the aluminum removing process is 5:1, the temperature is 50 ℃, the time is 60 minutes, and the waste lithium iron phosphate powder after aluminum removal and a lithium-rich solution containing aluminum impurities are obtained after suction filtration, wherein the lithium-rich solution is about 80 mL;
step (c): introducing carbon dioxide into the lithium-rich solution, stirring and precipitating aluminum for 2 hours at the temperature of 60 ℃, and filtering to obtain a purified lithium-rich solution and white aluminum slag;
step (d): mixing and leaching the waste lithium iron phosphate powder subjected to aluminum removal by adopting phosphoric acid and citric acid, wherein LiFePO is obtained4:H3PO4: the molar ratio of the citric acid is 1: 2.5: 0.15, the liquid-solid ratio in the leaching process is 4:1, the temperature is 50 ℃, the time is 3 hours, and green leaching liquid and black filter residue are obtained after filtration;
a step (e): supplementing 0.25mol of iron powder into the leaching solution, and rotating at the speed of 400rmp for 4 hours; continuously supplementing ferrous oxalate, adjusting the iron-phosphorus ratio in the system to be 1:1, supplementing starch with the mass of 8% of that of the target product as a carbon source, and continuously performing coarse grinding for 1 h;
step (f): mixing the coarsely ground slurry by using the lithium-rich solution obtained in the step (c), adjusting the solid content to 40%, and simultaneously supplementing lithium carbonate, wherein the molar ratio of the three elements of lithium, iron and phosphorus in the slurry is adjusted to 1-1.05: 1:1, so as to obtain slurry M; obtaining a lithium iron phosphate precursor powder material by adopting a sand grinding-spraying method for the slurry M;
and (g) calcining the precursor powder in an inert atmosphere at the temperature of 450 ℃ for 4h and at the temperature of 700 ℃ for 6h to obtain the black lithium iron phosphate active material.
The electrochemical performance test of the lithium iron phosphate cathode material prepared in the comparative example 1 was the same as that of the example 1.
Because the addition amount of the iron powder is more than 0.5 times of the molar weight of the phosphoric acid, the iron powder can not be completely converted into Fe in the high-energy ball milling3(PO4)2The unconverted iron powder is difficult to be uniformly mixed with the slurry, so that impurities such as FeP and the like are easily generated after argon sintering, and the electrochemical performance is influenced.
Through detection, the 1C capacity is 95.2mAh/g, the 2C capacity is 84.9mAh/g, and the 5C capacity is 77.3 mAh/g. The different-rate charge-discharge curve of the lithium iron phosphate recovered and regenerated in the comparative example 1 is shown in fig. 7.
Comparative example 2
The difference compared to example 2 is only that the rotational speed during mechanical activation is below the preferred range. The method comprises the following specific steps:
the lithium iron phosphate waste powder selected in the scheme comprises the following components: 3.8 wt.% of Li element, 33.5 wt.% of Fe element, 18.1 wt.% of P element, 0.9 wt.% of Al element, 1 wt.% of Cu element, and 8 wt.% of C element.
Step (a): the obtained disassembled waste lithium iron phosphate powder is hermetically calcined for 4 hours at 550 ℃ under the protection of inert atmosphere;
step (b): pre-removing aluminum from 17.5g of waste lithium iron phosphate powder (containing 0.1mol of lithium iron phosphate) by using 0.5mol/L lithium hydroxide solution, wherein the liquid-solid ratio in the aluminum removing process is 6:1, the temperature is 50 ℃, the time is 60 minutes, and the waste lithium iron phosphate powder after aluminum removal and a lithium-rich solution containing aluminum impurities are obtained after suction filtration, wherein the lithium-rich solution is about 100 mL;
step (c): introducing carbon dioxide into the lithium-rich solution, stirring and precipitating aluminum for 2 hours at the temperature of 60 ℃, and filtering to obtain a purified lithium-rich solution and white aluminum slag;
step (d): mixing and leaching the waste lithium iron phosphate powder subjected to aluminum removal by adopting phosphoric acid and citric acid, wherein LiFePO is obtained4:H3PO4: the molar ratio of the citric acid is 1: 2.5: 0.2, the liquid-solid ratio in the leaching process is 4:1, the temperature is 50 ℃, the time is 3 hours, and green leaching liquid and black filter residue are obtained after filtration;
a step (e): supplementing 0.1mol of iron powder into the leaching solution, and rotating at 150rmp for 4 h; continuously supplementing ferric oxide, adjusting the iron-phosphorus ratio in the system to be 1:1, supplementing starch with the mass of 10% of the target product as a carbon source, and continuously coarsely grinding for 1 h;
step (f): mixing the coarsely ground slurry by using the lithium-rich solution obtained in the step (c), adjusting the solid content to 32%, and simultaneously supplementing lithium carbonate, wherein the molar ratio of the three elements of lithium, iron and phosphorus in the slurry is adjusted to 1-1.05: 1:1, so as to obtain slurry M; obtaining a lithium iron phosphate precursor powder material by adopting a sand grinding-spraying method for the slurry M;
and (g) calcining the precursor powder in an inert atmosphere at the temperature of 450 ℃ for 4h and at the temperature of 700 ℃ for 6h to obtain the black lithium iron phosphate active material.
The electrochemical performance test of the lithium iron phosphate cathode material prepared in the comparative example 2 is the same as that of the example 1.
Through detection, the 1C capacity is 101.6mAh/g, the 2C capacity is 88.3mAh/g, and the 5C capacity is 71.3 mAh/g.
Comparative example 3
The only difference compared to example 1 is that the leaching process only employs phosphoric acid leaching. The method comprises the following specific steps:
step (a): the obtained disassembled waste lithium iron phosphate powder is hermetically calcined for 4 hours at 550 ℃ under the protection of inert atmosphere;
step (b): pre-removing aluminum from 17.4g of waste lithium iron phosphate powder (containing 0.1mol of lithium iron phosphate) by using 0.8mol/L lithium hydroxide solution, wherein the liquid-solid ratio in the aluminum removing process is 5:1, the temperature is 50 ℃, the time is 60 minutes, and the waste lithium iron phosphate powder after aluminum removal and a lithium-rich solution containing aluminum impurities are obtained after suction filtration, wherein the lithium-rich solution is about 80 mL;
step (c): introducing carbon dioxide into the lithium-rich solution, stirring and precipitating aluminum for 2 hours at the temperature of 60 ℃, and filtering to obtain a purified lithium-rich solution and white aluminum slag;
step (d): mixing and leaching the waste lithium iron phosphate powder subjected to aluminum removal by adopting phosphoric acid and citric acid, wherein LiFePO is obtained4:H3PO4The mol ratio is 1: 2.2, the liquid-solid ratio in the leaching process is 4:1, the temperature is 50 ℃, the time is 3 hours, and green leaching liquid and black filter residue are obtained after filtration;
through detection (the detection method and the detection instrument are the same as those in the example 1), the leaching rate of Li is 86%, the leaching rate of Fe is 79%, the leaching rate of P is 81%, the total leaching rate of lithium, iron and phosphorus is lower than 90%, and the economic benefit is lower.
Comparative example 4
Compared with example 3, the only difference is that the lithium iron phosphate waste powder is not subjected to aluminum pre-removal, and the subsequent lithium source is supplemented by lithium carbonate. The method comprises the following specific steps:
step (a): the obtained disassembled waste lithium iron phosphate powder is hermetically calcined for 4 hours at 550 ℃ under the protection of inert atmosphere;
step (d): the waste lithium iron phosphate powder is leached by mixing phosphoric acid and ascorbic acid, wherein LiFePO is adopted4:H3PO4: the molar ratio of the ascorbic acid is 1: 2.8: 0.2, the liquid-solid ratio in the leaching process is 6:1, the temperature is 60 ℃, the time is 5 hours, and green leaching liquid and black filter residue are obtained after filtration;
a step (e): supplementing 0.12mol of iron powder into the leaching solution, and rotating at the speed of 500rmp for 4 hours; continuously supplementing ferric oxide, adjusting the iron-phosphorus ratio in the system to be 1:1, supplementing starch with the mass of 10% of the target product as a carbon source, and continuously coarsely grinding for 1 h;
step (f): mixing the coarsely ground slurry by using ultrapure water, adjusting the solid content to 33%, simultaneously supplementing lithium hydroxide, and adjusting the molar ratio of the three elements of lithium, iron and phosphorus in the slurry to 1-1.05: 1:1 to obtain slurry M; obtaining a lithium iron phosphate precursor powder material by adopting a sand grinding-spraying method for the slurry M;
and (g) calcining the precursor powder in an inert atmosphere at the temperature of 450 ℃ for 4h and at the temperature of 700 ℃ for 6h to obtain the black lithium iron phosphate active material.
Through detection, the content of aluminum impurities in the lithium iron phosphate product is more than 4000ppm, and the content of the impurities exceeds the standard.
The electrochemical performance test of the lithium iron phosphate cathode material prepared in the comparative example 4 was the same as that of example 1.
Through detection, the 1C capacity is 131.8mAh/g, the 2C capacity is 117.5mAh/g, and the 5C capacity is 103.4 mAh/g.
Comparative example 5
Compared with example 1, the only difference is that the waste lithium iron phosphate powder is not subjected to the inert atmosphere calcination treatment. The method comprises the following specific steps:
step (a): pre-removing aluminum from 17.4g of waste lithium iron phosphate powder (containing 0.1mol of lithium iron phosphate) by using 0.8mol/L lithium hydroxide solution, wherein the liquid-solid ratio in the aluminum removing process is 5:1, the temperature is 50 ℃, the time is 60 minutes, and the waste lithium iron phosphate powder after aluminum removal and a lithium-rich solution containing aluminum impurities are obtained after suction filtration, wherein the lithium-rich solution is about 80 mL;
step (b): introducing carbon dioxide into the lithium-rich solution, stirring and precipitating aluminum for 2 hours at the temperature of 60 ℃, and filtering to obtain a purified lithium-rich solution and white aluminum slag;
step (c): mixing and leaching the waste lithium iron phosphate powder subjected to aluminum removal by adopting phosphoric acid and citric acid, wherein LiFePO is obtained4:H3PO4: the molar ratio of the citric acid is 1: 2.5: 0.15, the liquid-solid ratio in the leaching process is 4:1, the temperature is 50 ℃, the time is 3 hours, and green leaching liquid and black filter residue are obtained after filtration;
as organic matters such as the binder and the like in the waste powder are not decomposed, the leaching rate of each element in the leaching process is influenced to a great extent, and the leaching rate of Li is 91%, the leaching rate of Fe is 86%, the leaching rate of P is 85%, the overall leaching rate is not high and the slurry viscosity in the leaching process is too high through detection (the detection method and the detection instrument are the same as the embodiment 1).
The above-mentioned application examples are only illustrative and the present invention is described in detail by examples, which are only used for further illustration of the present invention and are not intended to limit the scope of the present invention, and those skilled in the art can make some insubstantial modifications and adaptations of the present invention.

Claims (10)

1. A method for recovering and regenerating lithium iron phosphorus components in waste lithium iron phosphate powder is characterized by comprising the following steps:
step (1): calcining the obtained disassembled waste lithium iron phosphate powder in a protective atmosphere;
step (2): pre-removing aluminum from the lithium iron phosphate waste powder obtained in the step (1) in a LiOH solution to obtain aluminum-removed waste powder and an aluminum-containing lithium-rich solution;
and (3): introducing carbon dioxide into the aluminum-containing lithium-rich solution to precipitate aluminum, and performing solid-liquid separation to obtain a purified lithium-rich solution;
and (4): mixing and leaching the aluminum-removed waste powder by adopting phosphoric acid and reducing organic acid; filtering to obtain leachate and filter residue;
and (5): supplementing iron powder into the leaching solution obtained in the step (4), mechanically activating, and reacting to form Fe3(PO4)2Sizing agent;
and (6): supplementing an iron source into the slurry to adjust the molar ratio of iron to phosphorus to be 1: 1-1: 1.03, and supplementing a carbon source for coarse grinding;
and (7): mixing the slurry obtained by coarse grinding in the step (6) by using the lithium-rich solution obtained in the step (3), and supplementing a lithium source to adjust the molar ratio of the three elements of lithium, iron and phosphorus in the slurry after mixing to 1-1.05: 1: 1-1.03; then, grinding by sand, and spray drying to obtain a lithium iron phosphate precursor powder material;
and (8): and sintering the lithium iron phosphate precursor powder material in a protective atmosphere to obtain the lithium iron phosphate positive active material.
2. The method for recycling the lithium iron phosphorus component from the waste lithium iron phosphate powder according to claim 1, wherein the waste lithium iron phosphate powder is a powder material obtained by disassembling and recycling waste lithium iron phosphate batteries;
preferably, the waste lithium iron phosphate powder contains a waste lithium iron phosphate positive electrode material and at least one of a negative electrode material, a binder, current collector impurity powder and residual electrolyte;
preferably, the waste lithium iron phosphate powder contains impurities containing at least one of copper, aluminum and carbon, wherein the impurities contain 1.0 wt.% or less of Cu, 1.5 wt.% or less of Al and 15 wt.% or less of carbon.
3. The method for recovering and regenerating the lithium iron phosphorus component in the waste lithium iron phosphate powder according to claim 1, wherein the protective atmosphere is an inert atmosphere or nitrogen; the inert atmosphere is preferably argon;
preferably, in the step (1), the calcining temperature is 500-700 ℃;
preferably, in the step (1), the calcination time is 4-8 hours.
4. The method for recovering and regenerating the lithium iron phosphorus component from the waste lithium iron phosphate powder according to claim 1, wherein in the step (2), the concentration of lithium hydroxide is 0.15-1 mol/L;
preferably, the liquid-solid ratio in the aluminum removing process is 5-8: 1;
preferably, the temperature is 40-60 ℃;
preferably, the time is 30 to 90 minutes.
5. The method for cyclically regenerating the lithium iron phosphorus component in the waste lithium iron phosphate powder according to claim 1, wherein the temperature of carbon dioxide introduced in the step (3) for precipitating aluminum is 40-70 ℃;
preferably for 2 to 4 hours.
6. The method for recovering and regenerating the lithium iron phosphorus component in the lithium iron phosphate waste powder according to claim 1, wherein the reducing organic acid in the step (4) is one or more of citric acid, ascorbic acid, lactic acid and formic acid.
7. According toThe method for recycling lithium iron phosphorus component from lithium iron phosphate waste powder as claimed in claim 1, wherein LiFePO is used in the step (4) for removing aluminum from the waste powder4LiFePO, namely4:H3PO4The molar ratio of the organic acid is 1: 2.2-3: 0.1 to 0.3.
Preferably, the liquid-solid ratio in the leaching process is 4-8: 1;
preferably, the leaching time is 3-5 h;
preferably, the leaching temperature is 50-60 ℃.
8. The method for recovering and regenerating the lithium iron phosphorus component in the waste lithium iron phosphate powder according to claim 1, wherein the addition amount of the iron powder in the step (5) is less than or equal to 0.5 time of the molar weight of the phosphoric acid;
preferably, the rotation speed of ball milling activation is 350 rmp-500 rmp;
preferably, the ball milling time is 4-6 h.
9. The method for recovering and regenerating the lithium iron phosphorus component from the waste lithium iron phosphate powder according to claim 1, wherein in the step (6), the iron source is at least one of organic acid salt and oxide of iron; preferably ferrous oxalate, Fe2O3、Fe3O4At least one of;
preferably, the carbon source is an organic carbon source, and the addition amount of the carbon source is 6-15% of the mass of the target product;
preferably, the lithium source is lithium carbonate or lithium oxyoxide;
preferably, the size mixing in the step (7) is to adjust the solid content of the size to be 25-45%;
preferably, the temperature of an air inlet is 240-260 ℃ and the temperature of an air outlet is 90-105 ℃ in the spray drying stage.
Preferably, the calcination temperature in the step (8) is 700-850 ℃;
preferably, the calcination time in the step (8) is 6-12 h.
10. The application of the lithium iron phosphate material prepared by the method according to any one of claims 1 to 9, which is characterized in that the lithium iron phosphate material is used as a positive electrode active material; the method is used for preparing the lithium ion battery.
CN202210015252.6A 2022-01-07 2022-01-07 Method for circularly regenerating lithium iron phosphorus component in lithium iron phosphate waste powder Active CN114212765B (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN202210015252.6A CN114212765B (en) 2022-01-07 2022-01-07 Method for circularly regenerating lithium iron phosphorus component in lithium iron phosphate waste powder

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN202210015252.6A CN114212765B (en) 2022-01-07 2022-01-07 Method for circularly regenerating lithium iron phosphorus component in lithium iron phosphate waste powder

Publications (2)

Publication Number Publication Date
CN114212765A true CN114212765A (en) 2022-03-22
CN114212765B CN114212765B (en) 2023-06-20

Family

ID=80708250

Family Applications (1)

Application Number Title Priority Date Filing Date
CN202210015252.6A Active CN114212765B (en) 2022-01-07 2022-01-07 Method for circularly regenerating lithium iron phosphorus component in lithium iron phosphate waste powder

Country Status (1)

Country Link
CN (1) CN114212765B (en)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN115340080A (en) * 2022-08-29 2022-11-15 株洲冶炼集团股份有限公司 Method for regenerating waste lithium iron phosphate powder
WO2024212075A1 (en) * 2023-04-10 2024-10-17 广东邦普循环科技有限公司 Repair and regeneration method for lithium iron phosphate

Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2018192122A1 (en) * 2017-04-18 2018-10-25 中科过程(北京)科技有限公司 Method for mixed acid leaching and recovery of positive electrode materials of waste lithium ion batteries
CN110112481A (en) * 2019-04-23 2019-08-09 北京科技大学 Waste lithium iron phosphate battery recycles the method for preparing lithium iron phosphate positive material
CN112054261A (en) * 2020-07-28 2020-12-08 昆明理工大学 Method for recovering waste lithium battery positive electrode through mechanical activation assisted spray pyrolysis
CN112310499A (en) * 2019-07-31 2021-02-02 中国科学院过程工程研究所 Recovery method of waste lithium iron phosphate material and obtained recovery liquid
CN112897492A (en) * 2021-01-25 2021-06-04 中南大学 Method for regenerating and recycling high-impurity lithium iron phosphate waste powder
CN113322380A (en) * 2021-08-02 2021-08-31 清大国华环境集团股份有限公司 Recycling treatment method of power lithium battery
CN113846235A (en) * 2021-11-16 2021-12-28 中国科学院化学研究所 Closed-loop recycling method for lithium in lithium ion battery
CN113880064A (en) * 2021-11-09 2022-01-04 株洲冶炼集团股份有限公司 Method for treating high-impurity lithium iron phosphate waste powder by using low-consumption phosphoric acid

Patent Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2018192122A1 (en) * 2017-04-18 2018-10-25 中科过程(北京)科技有限公司 Method for mixed acid leaching and recovery of positive electrode materials of waste lithium ion batteries
CN110112481A (en) * 2019-04-23 2019-08-09 北京科技大学 Waste lithium iron phosphate battery recycles the method for preparing lithium iron phosphate positive material
CN112310499A (en) * 2019-07-31 2021-02-02 中国科学院过程工程研究所 Recovery method of waste lithium iron phosphate material and obtained recovery liquid
CN112054261A (en) * 2020-07-28 2020-12-08 昆明理工大学 Method for recovering waste lithium battery positive electrode through mechanical activation assisted spray pyrolysis
CN112897492A (en) * 2021-01-25 2021-06-04 中南大学 Method for regenerating and recycling high-impurity lithium iron phosphate waste powder
CN113322380A (en) * 2021-08-02 2021-08-31 清大国华环境集团股份有限公司 Recycling treatment method of power lithium battery
CN113880064A (en) * 2021-11-09 2022-01-04 株洲冶炼集团股份有限公司 Method for treating high-impurity lithium iron phosphate waste powder by using low-consumption phosphoric acid
CN113846235A (en) * 2021-11-16 2021-12-28 中国科学院化学研究所 Closed-loop recycling method for lithium in lithium ion battery

Non-Patent Citations (3)

* Cited by examiner, † Cited by third party
Title
JOEY CHUNG-YEN JUNG ET.AL: "A review of recycling spent lithium-ion battery cathode materials using hydrometallurgical treatments", 《JOURNAL OF ENERGY STORAGE》 *
伍德佑: "废旧磷酸铁锂电池正极材料回收", 《有色金属(冶炼部分)》 *
许 奎: "废旧磷酸铁锂的高效回收再利用", 《电池》 *

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN115340080A (en) * 2022-08-29 2022-11-15 株洲冶炼集团股份有限公司 Method for regenerating waste lithium iron phosphate powder
WO2024212075A1 (en) * 2023-04-10 2024-10-17 广东邦普循环科技有限公司 Repair and regeneration method for lithium iron phosphate

Also Published As

Publication number Publication date
CN114212765B (en) 2023-06-20

Similar Documents

Publication Publication Date Title
Zhao et al. Regeneration and reutilization of cathode materials from spent lithium-ion batteries
CN106910889B (en) A method of regenerating positive active material from waste lithium iron phosphate battery
Yang et al. Recovery and regeneration of LiFePO 4 from spent lithium-ion batteries via a novel pretreatment process
CN111392750B (en) Method for removing impurities and recovering lithium from waste lithium ion batteries
CN111799522B (en) Method for recovering positive electrode material, positive electrode material obtained by the method, and use of the positive electrode material
CN106848471A (en) A kind of nitration mixture of waste lithium ion cell anode material is leached and recovery method
CN111270072B (en) Recycling method of waste lithium iron phosphate battery positive electrode material
CN114195112A (en) Recovery method of waste lithium iron phosphate battery
CN112897492B (en) Method for regenerating and recycling high-impurity lithium iron phosphate waste powder
CN110620278A (en) Method for recovering anode material of waste lithium iron phosphate battery
CN101555030A (en) Method for recovering and recycling waste lithium ion battery cathode material
CN111430832B (en) Full resource recovery method for waste ternary lithium ion battery without discharge pretreatment
KR20210075502A (en) Method for recovering valuable metals from cathodic active material of used lithium battery
CN113437378A (en) Method for recycling and reusing anode and cathode of waste battery
CN114212765B (en) Method for circularly regenerating lithium iron phosphorus component in lithium iron phosphate waste powder
CN114229816A (en) Method for recycling and preparing anode material from waste lithium iron phosphate battery
CN112174106A (en) Battery-grade iron phosphate and preparation method thereof
CN114709504A (en) Clean recovery method of waste lithium iron phosphate anode material
CN112047320A (en) Treatment method for low-pollution recycling of lithium iron phosphate material
CN114725557A (en) Recycling method of lithium iron phosphate waste
CN113381089B (en) Method for preparing nano lithium iron phosphate material by recycling ferrous phosphate
CN116119638B (en) Method for preparing lithium iron manganese phosphate by recycling waste lithium iron phosphate powder
CN115744857B (en) Method for preparing lithium iron phosphate positive electrode material by directional circulation of waste lithium iron phosphate battery
CN116706302A (en) Lithium battery recycling method
CN115924879A (en) Method for recycling lithium iron phosphate from scrap lithium iron phosphate material

Legal Events

Date Code Title Description
PB01 Publication
PB01 Publication
SE01 Entry into force of request for substantive examination
SE01 Entry into force of request for substantive examination
GR01 Patent grant
GR01 Patent grant