CN114512737A - Novel oxidation lithium leaching method for waste lithium iron phosphate - Google Patents
Novel oxidation lithium leaching method for waste lithium iron phosphate Download PDFInfo
- Publication number
- CN114512737A CN114512737A CN202111581434.1A CN202111581434A CN114512737A CN 114512737 A CN114512737 A CN 114512737A CN 202111581434 A CN202111581434 A CN 202111581434A CN 114512737 A CN114512737 A CN 114512737A
- Authority
- CN
- China
- Prior art keywords
- lithium
- iron phosphate
- filtrate
- leaching
- waste
- 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.)
- Withdrawn
Links
- GELKBWJHTRAYNV-UHFFFAOYSA-K lithium iron phosphate Chemical compound [Li+].[Fe+2].[O-]P([O-])([O-])=O GELKBWJHTRAYNV-UHFFFAOYSA-K 0.000 title claims abstract description 60
- WHXSMMKQMYFTQS-UHFFFAOYSA-N Lithium Chemical compound [Li] WHXSMMKQMYFTQS-UHFFFAOYSA-N 0.000 title claims abstract description 53
- 229910052744 lithium Inorganic materials 0.000 title claims abstract description 53
- 239000002699 waste material Substances 0.000 title claims abstract description 46
- 238000000034 method Methods 0.000 title claims abstract description 43
- 238000002386 leaching Methods 0.000 title claims abstract description 34
- 230000003647 oxidation Effects 0.000 title claims abstract description 11
- 238000007254 oxidation reaction Methods 0.000 title claims abstract description 11
- HEMHJVSKTPXQMS-UHFFFAOYSA-M Sodium hydroxide Chemical compound [OH-].[Na+] HEMHJVSKTPXQMS-UHFFFAOYSA-M 0.000 claims abstract description 54
- 239000000706 filtrate Substances 0.000 claims abstract description 52
- 230000001590 oxidative effect Effects 0.000 claims abstract description 43
- 238000001914 filtration Methods 0.000 claims abstract description 29
- 239000007800 oxidant agent Substances 0.000 claims abstract description 26
- RTBHLGSMKCPLCQ-UHFFFAOYSA-N [Mn].OOO Chemical compound [Mn].OOO RTBHLGSMKCPLCQ-UHFFFAOYSA-N 0.000 claims abstract description 24
- 239000000843 powder Substances 0.000 claims abstract description 24
- WBJZTOZJJYAKHQ-UHFFFAOYSA-K iron(3+) phosphate Chemical compound [Fe+3].[O-]P([O-])([O-])=O WBJZTOZJJYAKHQ-UHFFFAOYSA-K 0.000 claims abstract description 21
- 229910000398 iron phosphate Inorganic materials 0.000 claims abstract description 19
- OAICVXFJPJFONN-UHFFFAOYSA-N Phosphorus Chemical compound [P] OAICVXFJPJFONN-UHFFFAOYSA-N 0.000 claims abstract description 16
- 229910052698 phosphorus Inorganic materials 0.000 claims abstract description 16
- 239000011574 phosphorus Substances 0.000 claims abstract description 16
- 230000008569 process Effects 0.000 claims abstract description 16
- CDBYLPFSWZWCQE-UHFFFAOYSA-L Sodium Carbonate Chemical compound [Na+].[Na+].[O-]C([O-])=O CDBYLPFSWZWCQE-UHFFFAOYSA-L 0.000 claims abstract description 14
- QAOWNCQODCNURD-UHFFFAOYSA-N Sulfuric acid Chemical compound OS(O)(=O)=O QAOWNCQODCNURD-UHFFFAOYSA-N 0.000 claims abstract description 13
- XGZVUEUWXADBQD-UHFFFAOYSA-L lithium carbonate Chemical compound [Li+].[Li+].[O-]C([O-])=O XGZVUEUWXADBQD-UHFFFAOYSA-L 0.000 claims abstract description 13
- 229910052808 lithium carbonate Inorganic materials 0.000 claims abstract description 13
- 238000004064 recycling Methods 0.000 claims abstract description 11
- 238000003756 stirring Methods 0.000 claims abstract description 9
- 230000001376 precipitating effect Effects 0.000 claims abstract description 8
- 239000002893 slag Substances 0.000 claims abstract description 8
- CWYNVVGOOAEACU-UHFFFAOYSA-N Fe2+ Chemical compound [Fe+2] CWYNVVGOOAEACU-UHFFFAOYSA-N 0.000 claims abstract description 7
- 238000001556 precipitation Methods 0.000 claims abstract description 7
- 229910000029 sodium carbonate Inorganic materials 0.000 claims abstract description 7
- VTLYFUHAOXGGBS-UHFFFAOYSA-N Fe3+ Chemical compound [Fe+3] VTLYFUHAOXGGBS-UHFFFAOYSA-N 0.000 claims abstract description 5
- JEIPFZHSYJVQDO-UHFFFAOYSA-N iron(III) oxide Inorganic materials O=[Fe]O[Fe]=O JEIPFZHSYJVQDO-UHFFFAOYSA-N 0.000 claims abstract description 5
- 238000005273 aeration Methods 0.000 claims abstract description 4
- 239000002033 PVDF binder Substances 0.000 claims abstract description 3
- 239000006229 carbon black Substances 0.000 claims abstract description 3
- 229920002981 polyvinylidene fluoride Polymers 0.000 claims abstract description 3
- XEEYBQQBJWHFJM-UHFFFAOYSA-N iron Substances [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 claims description 26
- 238000005406 washing Methods 0.000 claims description 15
- 229910052742 iron Inorganic materials 0.000 claims description 14
- HBBGRARXTFLTSG-UHFFFAOYSA-N Lithium ion Chemical compound [Li+] HBBGRARXTFLTSG-UHFFFAOYSA-N 0.000 claims description 9
- 238000006243 chemical reaction Methods 0.000 claims description 9
- 229910001416 lithium ion Inorganic materials 0.000 claims description 9
- 239000007788 liquid Substances 0.000 claims description 8
- 239000002244 precipitate Substances 0.000 claims description 8
- 239000002002 slurry Substances 0.000 claims description 7
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 7
- 238000010438 heat treatment Methods 0.000 claims description 5
- 238000002156 mixing Methods 0.000 claims description 5
- 239000000047 product Substances 0.000 claims description 5
- PXHVJJICTQNCMI-UHFFFAOYSA-N Nickel Chemical compound [Ni] PXHVJJICTQNCMI-UHFFFAOYSA-N 0.000 claims description 4
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 claims description 4
- 229910001437 manganese ion Inorganic materials 0.000 claims description 4
- 229910052760 oxygen Inorganic materials 0.000 claims description 4
- 239000001301 oxygen Substances 0.000 claims description 4
- 239000010452 phosphate Substances 0.000 claims description 4
- 230000035484 reaction time Effects 0.000 claims description 4
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 claims description 3
- 229910052782 aluminium Inorganic materials 0.000 claims description 3
- -1 iron ions Chemical class 0.000 claims description 3
- OYPRJOBELJOOCE-UHFFFAOYSA-N Calcium Chemical compound [Ca] OYPRJOBELJOOCE-UHFFFAOYSA-N 0.000 claims description 2
- DGAQECJNVWCQMB-PUAWFVPOSA-M Ilexoside XXIX Chemical compound C[C@@H]1CC[C@@]2(CC[C@@]3(C(=CC[C@H]4[C@]3(CC[C@@H]5[C@@]4(CC[C@@H](C5(C)C)OS(=O)(=O)[O-])C)C)[C@@H]2[C@]1(C)O)C)C(=O)O[C@H]6[C@@H]([C@H]([C@@H]([C@H](O6)CO)O)O)O.[Na+] DGAQECJNVWCQMB-PUAWFVPOSA-M 0.000 claims description 2
- FYYHWMGAXLPEAU-UHFFFAOYSA-N Magnesium Chemical compound [Mg] FYYHWMGAXLPEAU-UHFFFAOYSA-N 0.000 claims description 2
- PWHULOQIROXLJO-UHFFFAOYSA-N Manganese Chemical compound [Mn] PWHULOQIROXLJO-UHFFFAOYSA-N 0.000 claims description 2
- 229910019142 PO4 Inorganic materials 0.000 claims description 2
- 239000011575 calcium Substances 0.000 claims description 2
- 229910052791 calcium Inorganic materials 0.000 claims description 2
- 239000010941 cobalt Substances 0.000 claims description 2
- 229910017052 cobalt Inorganic materials 0.000 claims description 2
- GUTLYIVDDKVIGB-UHFFFAOYSA-N cobalt atom Chemical compound [Co] GUTLYIVDDKVIGB-UHFFFAOYSA-N 0.000 claims description 2
- 229910001448 ferrous ion Inorganic materials 0.000 claims description 2
- 229910000155 iron(II) phosphate Inorganic materials 0.000 claims description 2
- 239000011777 magnesium Substances 0.000 claims description 2
- 229910052749 magnesium Inorganic materials 0.000 claims description 2
- 229910052748 manganese Inorganic materials 0.000 claims description 2
- 239000011572 manganese Substances 0.000 claims description 2
- IPJKJLXEVHOKSE-UHFFFAOYSA-L manganese dihydroxide Chemical compound [OH-].[OH-].[Mn+2] IPJKJLXEVHOKSE-UHFFFAOYSA-L 0.000 claims description 2
- 229910052759 nickel Inorganic materials 0.000 claims description 2
- 239000002245 particle Substances 0.000 claims description 2
- 238000002360 preparation method Methods 0.000 claims description 2
- 239000011734 sodium Substances 0.000 claims description 2
- 229910052708 sodium Inorganic materials 0.000 claims description 2
- NCZYUKGXRHBAHE-UHFFFAOYSA-K [Li+].P(=O)([O-])([O-])[O-].[Fe+2].[Li+] Chemical compound [Li+].P(=O)([O-])([O-])[O-].[Fe+2].[Li+] NCZYUKGXRHBAHE-UHFFFAOYSA-K 0.000 claims 1
- 239000007789 gas Substances 0.000 claims 1
- MHAJPDPJQMAIIY-UHFFFAOYSA-N Hydrogen peroxide Chemical compound OO MHAJPDPJQMAIIY-UHFFFAOYSA-N 0.000 abstract description 12
- 238000001704 evaporation Methods 0.000 abstract description 4
- PVIFNYFAXIMOKR-UHFFFAOYSA-M manganese(3+);oxygen(2-);hydroxide Chemical compound [OH-].[O-2].[Mn+3] PVIFNYFAXIMOKR-UHFFFAOYSA-M 0.000 abstract description 2
- 125000004122 cyclic group Chemical group 0.000 abstract 1
- 238000011084 recovery Methods 0.000 description 29
- 230000000694 effects Effects 0.000 description 6
- 239000000243 solution Substances 0.000 description 6
- 239000002253 acid Substances 0.000 description 5
- 239000003513 alkali Substances 0.000 description 5
- 239000010405 anode material Substances 0.000 description 4
- 238000005272 metallurgy Methods 0.000 description 4
- 238000004140 cleaning Methods 0.000 description 3
- 150000002696 manganese Chemical class 0.000 description 3
- 239000005955 Ferric phosphate Substances 0.000 description 2
- 229940032958 ferric phosphate Drugs 0.000 description 2
- 239000012535 impurity Substances 0.000 description 2
- 229910000399 iron(III) phosphate Inorganic materials 0.000 description 2
- 239000012452 mother liquor Substances 0.000 description 2
- 239000002351 wastewater Substances 0.000 description 2
- PMZURENOXWZQFD-UHFFFAOYSA-L Sodium Sulfate Chemical compound [Na+].[Na+].[O-]S([O-])(=O)=O PMZURENOXWZQFD-UHFFFAOYSA-L 0.000 description 1
- 238000002441 X-ray diffraction Methods 0.000 description 1
- 239000006227 byproduct Substances 0.000 description 1
- 238000001354 calcination Methods 0.000 description 1
- 238000009388 chemical precipitation Methods 0.000 description 1
- 239000012141 concentrate Substances 0.000 description 1
- 230000007797 corrosion Effects 0.000 description 1
- 238000005260 corrosion Methods 0.000 description 1
- 238000002425 crystallisation Methods 0.000 description 1
- 230000008025 crystallization Effects 0.000 description 1
- 230000008021 deposition Effects 0.000 description 1
- 238000005265 energy consumption Methods 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 230000007613 environmental effect Effects 0.000 description 1
- 238000003912 environmental pollution Methods 0.000 description 1
- 230000008020 evaporation Effects 0.000 description 1
- 238000000605 extraction Methods 0.000 description 1
- XEMZLVDIUVCKGL-UHFFFAOYSA-N hydrogen peroxide;sulfuric acid Chemical compound OO.OS(O)(=O)=O XEMZLVDIUVCKGL-UHFFFAOYSA-N 0.000 description 1
- 238000009776 industrial production Methods 0.000 description 1
- 235000014413 iron hydroxide Nutrition 0.000 description 1
- NCNCGGDMXMBVIA-UHFFFAOYSA-L iron(ii) hydroxide Chemical compound [OH-].[OH-].[Fe+2] NCNCGGDMXMBVIA-UHFFFAOYSA-L 0.000 description 1
- 150000002642 lithium compounds Chemical class 0.000 description 1
- 229910001386 lithium phosphate Inorganic materials 0.000 description 1
- 239000011259 mixed solution Substances 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000035699 permeability Effects 0.000 description 1
- 235000021110 pickles Nutrition 0.000 description 1
- 238000000746 purification Methods 0.000 description 1
- 230000008929 regeneration Effects 0.000 description 1
- 238000011069 regeneration method Methods 0.000 description 1
- 230000008439 repair process Effects 0.000 description 1
- 238000000926 separation method Methods 0.000 description 1
- 229910052938 sodium sulfate Inorganic materials 0.000 description 1
- 235000011152 sodium sulphate Nutrition 0.000 description 1
- 239000007787 solid Substances 0.000 description 1
- 239000007790 solid phase Substances 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
- 239000000725 suspension Substances 0.000 description 1
- TWQULNDIKKJZPH-UHFFFAOYSA-K trilithium;phosphate Chemical compound [Li+].[Li+].[Li+].[O-]P([O-])([O-])=O TWQULNDIKKJZPH-UHFFFAOYSA-K 0.000 description 1
- 238000003828 vacuum filtration Methods 0.000 description 1
- 239000010926 waste battery Substances 0.000 description 1
Images
Classifications
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M10/00—Secondary cells; Manufacture thereof
- H01M10/54—Reclaiming serviceable parts of waste accumulators
-
- Y—GENERAL 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
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02W—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO WASTEWATER TREATMENT OR WASTE MANAGEMENT
- Y02W30/00—Technologies for solid waste management
- Y02W30/50—Reuse, recycling or recovery technologies
- Y02W30/84—Recycling of batteries or fuel cells
Landscapes
- Engineering & Computer Science (AREA)
- Manufacturing & Machinery (AREA)
- Chemical & Material Sciences (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Electrochemistry (AREA)
- General Chemical & Material Sciences (AREA)
- Processing Of Solid Wastes (AREA)
- Manufacture And Refinement Of Metals (AREA)
Abstract
The invention discloses a novel method for oxidizing and leaching lithium from waste lithium iron phosphate, which comprises the following specific operations: firstly, dissolving and stirring lithium iron phosphate powder by using sulfuric acid, separating carbon black and PVDF to obtain a lithium-containing filtrate to realize leaching of lithium; adding an oxidant namely manganese oxyhydroxide to oxidize ferrous iron in the filtrate into ferric iron, filtering out redundant oxidant, adding sodium hydroxide into the filtrate to adjust the pH value, precipitating and recovering the iron phosphate, continuously adding sodium hydroxide into the separated filtrate to adjust the pH value, and carrying out aeration oxidation to obtain manganese oxyhydroxide to realize cyclic utilization; evaporating and concentrating the filtrate after separating the hydroxyl manganese oxide, adding sodium carbonate for precipitation and recycling to obtain lithium carbonate; the invention discloses a recyclable oxidant to improve the existing waste lithium iron phosphate wet leaching process, the process does not need hydrogen peroxide, is green and environment-friendly, solves the problem of treatment of phosphorus-containing slag in the existing process, and recovers iron phosphate and lithium carbonate.
Description
Technical Field
The invention relates to the technical field of scrapped lithium ion battery recovery, in particular to a novel method for oxidizing and leaching lithium from waste lithium iron phosphate.
Background
With the increasing attention on the environment in the world, the trend of new energy vehicles is about to increase in a burst manner, and as for China, the permeability of new energy vehicles in the half year before 2021 is broken by 10% at first, and the national given target is completed in advance. In new energy automobiles, the lithium iron phosphate battery has excellent performance, meets the requirements of new energy electric automobiles, particularly blade batteries are in the present, the safety and the cost performance of the lithium iron phosphate battery are widely seen by various large automobile enterprises, and the lithium iron phosphate battery gradually has the trend of overtaking ternary batteries. The increasing demand is accompanied by the problem of scrap recycling, the recycling process of the ternary battery is gradually mature at present, and the recycling of the lithium iron phosphate battery which is not seen before is still in an early stage. In the face of this large cake, which is urgently needed to be developed, social advices and market concerns are in the spotlight on it sooner or later.
The recovery process of the waste lithium iron phosphate battery comprises a dry metallurgy recovery process, a wet metallurgy recovery process, a biological metallurgy recovery process, a dry and wet metallurgy combined recovery process, a repair and reuse technology and the like. At present, the recovery of lithium iron phosphate anode materials is mainly wet recovery, which is to selectively leach anode material powder with alkali or acid according to a dissolving-precipitating process route, concentrate leachate, and recover the anode material powder in a chemical precipitation or extraction manner. The hydrometallurgical recovery process has a long process flow, but the energy consumption is relatively low, the recovery rate is high, the selective leaching of lithium by sulfuric acid-hydrogen peroxide is a mature recovery process of the lithium iron phosphate anode material at present, but the consumption of hydrogen peroxide can increase the recovery cost, the selective leaching of lithium does not recover phosphorus and iron, and phosphorus-containing slag can cause certain damage to the environment.
The invention patent CN106848473B (a selective recovery method of lithium in waste lithium iron phosphate batteries) provides a selective recovery method of lithium in waste lithium iron phosphate batteries, which is characterized in that powder is oxidized in an oxidizing condition/medium, so that ferrous iron is converted into ferric iron, the pH value is adjusted during the oxidation treatment, lithium elements are selectively leached in an iron hydroxide stable area, and high-purity lithium carbonate is obtained through further treatment; the process simplifies the waste battery recovery process, and the obtained leachate has low impurity content, so that an additional leachate purification process is not needed, and the process is simple and low in cost. But the use of the oxidant increases the recovery cost of the battery, the leaching rate of lithium is lower, and the recovery of phosphorus and iron is not involved. In patent CN112331949A (a method for recovering phosphorus, iron and lithium from waste lithium iron phosphate batteries), after alkali is dissolved and aluminum is removed, lithium iron phosphate powder is added into a mixed solution of sulfuric acid and hydrogen peroxide, and is heated and leached to obtain an acid leaching solution; adjusting the pH value of the pickle liquor to obtain crude iron phosphate; dissolving, precipitating and calcining the rough ferric phosphate to obtain battery-grade ferric phosphate; and (3) evaporating and concentrating the lithium-containing filtrate, and then adding an alkali solution to obtain a lithium carbonate precipitate, thereby obtaining the battery-grade lithium carbonate. The method has the advantages of short process flow, simple reaction system and no generation of iron-containing waste residues and phosphorus-containing wastewater. The consumption of acid and alkali is too large, the pressure of acid and alkali waste liquid to the environment is too large, and although the addition of hydrogen peroxide reduces the consumption of acid, the hydrogen peroxide cannot be recycled. CN113234929A (a method and a product for recovering lithium from waste lithium iron phosphate batteries) makes a solid-phase oxidant and lithium iron phosphate powder react in a high-energy impact reactor for a set time to obtain fully-reacted lithium iron phosphate powder; washing to obtain a suspension of lithium iron phosphate powder; performing vacuum filtration separation to obtain black solid powder and lithium mother liquor; recovering lithium compounds in the lithium mother liquor; and recovering a byproduct after the precipitation liquid after the lithium is recovered is subjected to evaporation and crystallization treatment. The product included iron phosphate, lithium phosphate and sodium sulfate. The method can avoid the problem of equipment corrosion and reduce the problem of environmental pollution caused by waste water and waste liquid. But the use of the oxidant can not be recycled, so that the recovery cost of the battery is increased, and the purity of the recovered product is not high.
Therefore, a novel method for oxidizing and leaching lithium from waste lithium iron phosphate, which is economical in cost, high in recycling rate, environment-friendly and energy-saving, is needed in the technical field.
Disclosure of Invention
In order to solve the technical problems, the invention provides a novel method for oxidizing and leaching waste lithium iron phosphate, which is economical in cost, high in recovery rate, environment-friendly and energy-saving.
In order to achieve the purpose, the technical scheme of the invention is as follows:
a novel method for oxidizing and leaching lithium of waste lithium iron phosphate adopts an oxidant circulation process route, and when lithium is oxidized and leached, a reduced oxidant is activated by air or oxygen and then is reused for oxidizing and leaching lithium of the lithium iron phosphate, and comprises the following steps:
step S1, mixing waste lithium iron phosphate powder, concentrated sulfuric acid and pure water into slurry according to a certain proportion, reacting for a certain time, and filtering to obtain filtrate a containing lithium ions, ferrous ions and phosphate radicals and filter residue a containing carbon black and PVDF;
step S2, adding an oxidant namely manganese oxyhydroxide into the filtrate a obtained in the step S1, controlling the pH value to be 0-1, and performing precipitation and filtration to obtain filter residue containing redundant oxidant and filtrate b containing lithium ions, iron ions with valence III, manganese ions with valence II and phosphate radicals;
step S3, washing and filtering the filter residue a in the step S1, wherein the washing liquid contains lithium ions and the washing liquid is circulated back to the slurry preparation in the step S1;
step S4, adding a sodium hydroxide solution into the filtrate b obtained in the step S2, adjusting the pH value to form an iron phosphate precipitate, and filtering and separating filtrate d containing lithium ions and manganese ions and iron phosphate filter residues;
step S5, sodium hydroxide is continuously added into the filtrate d of the step S4 to adjust the pH value, manganese hydroxide precipitate is produced, manganese oxyhydroxide is formed through aeration oxidation, manganese oxyhydroxide slag and lithium-containing filtrate e are obtained through filtration, and the manganese oxyhydroxide slag is recycled to the step S2 after being cleaned;
and S6, heating and concentrating the filtrate e in the step S5, adding sodium carbonate while the filtrate is hot to precipitate lithium, and filtering and washing to obtain lithium carbonate.
Further, in step S1, the particle size of the waste lithium iron phosphate powder is 60-150 meshes, wherein the iron content is 30-35 wt.%, the lithium content is 3.5-4.5 wt.%, and the phosphorus content is 18-23 wt.%.
Still further, the waste lithium iron phosphate powder in step S1 further contains sodium, magnesium, nickel, aluminum, calcium, cobalt, and manganese.
Further, in step S1, the weight ratio of the waste lithium iron phosphate powder to the concentrated sulfuric acid is 5: 3, the proportion range of the waste lithium iron phosphate powder to the water is 1: 3-1: 5, the reaction time range is 1-5 hours, the pH value of the filtrate is controlled within the range of 0.3-0.8, and the technical effects are as follows: the leaching rates of phosphorus, iron and lithium can reach 97 percent.
Further, in the step S2, the oxidizing agent, namely the hydroxyl manganese oxide, the lithium iron phosphate has a molar ratio of 1-1.2, a temperature of 30-60 ℃ and a time of 2-5 hours; and oxidizing ferrous iron in the filtrate into ferric iron.
Further, adding sodium hydroxide to adjust the pH value to 1.9-2.2 in the step S4; the iron phosphate is recovered by precipitation, and the technical effects realized by the method are as follows: the recovery rate of the iron phosphate can reach about 90 percent.
Further, sodium hydroxide is continuously added in the step S5 to adjust the pH value to 9-11 for 1-3 hours, the aerated air source is air or oxygen, and the aerated product is manganese oxyhydroxide serving as a recycled oxidant.
Furthermore, in the step S6, the reaction temperature of lithium deposition is 100 ℃, the reaction time is 1-3 h, and the stirring speed is 200-300 rpm, so that the technical effects are as follows: the recovery rate of lithium can reach about 90%.
The invention uses a novel oxidant to prepare lithium carbonate and iron phosphate from waste lithium iron phosphate powder through green, economic and environment-friendly recovery; leaching lithium iron phosphate by dissolving with sulfuric acid; then adding an oxidant of manganese oxyhydroxide to oxidize ferrous iron into ferric iron, and filtering to remove impurities; then adding sodium hydroxide to adjust pH value, precipitating and recovering iron phosphate, and continuously adding sodium hydroxide to carry out aeration oxidation precipitation to obtain manganese oxyhydroxide so as to realize the recycling of the oxidant; finally evaporating, concentrating, adding sodium carbonate, precipitating and recovering to obtain battery-grade lithium carbonate; the invention adopts the efficient recyclable oxidant and improves the existing waste lithium iron phosphate sulfuric acid-hydrogen peroxide wet leaching process. Green and environment-friendly, has low cost, solves the problem of treatment of phosphorus-containing slag in the prior art, and can be applied to large-scale industrial production.
Drawings
In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only some embodiments of the present invention, and it is obvious for those skilled in the art that other drawings can be obtained based on these drawings without creative efforts.
FIG. 1 is a flow chart of a novel oxidation lithium leaching process for waste lithium iron phosphate;
FIG. 2 is an XRD analysis curve of lithium carbonate obtained by the method for recovering waste lithium iron phosphate powder
Detailed Description
In order to facilitate an understanding of the invention, the invention will be described more fully and in detail below with reference to the accompanying drawings and preferred embodiments, but the scope of the invention is not limited to the specific embodiments below. It should be noted that the embodiments and features of the embodiments may be combined with each other without conflict.
In order to realize the purpose of the invention, the technical scheme provided by the invention is as follows:
example 1
A novel method for oxidizing and leaching lithium from waste lithium iron phosphate comprises the following steps:
(1) mixing waste lithium iron phosphate powder, concentrated sulfuric acid and water in a weight ratio of 5: 4: 25, reacting for 2 hours, wherein the pH value of the filtrate is 0.5, filtering to obtain filtrate a and filter residue a, and the leaching rates of phosphorus, iron and lithium reach 98%;
(2) washing and filtering the filter residue a obtained by the reaction in the step 1), circularly preparing slurry in the step 1 by using a washing liquid c, adding manganese oxyhydroxide with the molar ratio of 1 to lithium iron phosphate into the filtrate a, stirring for 1 hour at 30 ℃, wherein the pH value is 0.8, and precipitating and filtering insoluble substances in an oxidant;
(3) adding sodium hydroxide into the filtrate obtained in the step 2), adjusting the pH value to 2.0 to form iron phosphate precipitate, and filtering and separating filtrate d, wherein the recovery rate of the iron phosphate is 90.8%;
(4) continuously adding sodium hydroxide into the filtrate d in the step 3) to adjust the pH value to 10, aerating for 2 hours in air, oxidizing manganese salt to form manganese oxyhydroxide, filtering to obtain filter residue e and filtrate e, and recycling the filter residue e, namely the manganese oxyhydroxide after cleaning to the step 2);
(5) and adding sodium carbonate into the filtrate e at the reaction temperature of 100 ℃ for 3h and the stirring speed of 300rpm, heating and concentrating, and recovering to obtain the lithium carbonate. The recovery of lithium was 91.05%.
The existing waste lithium iron phosphate wet leaching process is improved by the novel oxidant capable of being recycled. The process does not need hydrogen peroxide, is green and environment-friendly and has low cost; the problem of treatment of the phosphorus-containing slag in the prior art is solved; comprehensively recover phosphorus, iron and lithium, and almost no waste residue is discharged. Therefore, the recycling regeneration of the lithium, phosphorus and iron resources of the scrapped lithium iron phosphate power battery is realized, the effect is obvious, the simplicity and the practicability are realized, and the characteristics of environmental protection, high efficiency, low cost, simple process, high recovery rate and large-scale industrial popularization are realized.
Example 2
The method for the novel oxidation lithium leaching of the waste lithium iron phosphate in the embodiment is basically the same as that of the embodiment 1, and the achieved effects are basically the same as that of the embodiment:
(1) mixing waste lithium iron phosphate powder, concentrated sulfuric acid and water in a weight ratio of 5: 4: 15, reacting for 2 hours, wherein the pH value of the filtrate is 0.3, filtering to obtain filtrate a and filter residue a, and the leaching rates of phosphorus, iron and lithium reach 99%;
(2) washing and filtering the filter residue a obtained by the reaction in the step 1), circularly preparing slurry in the step 1 by using a washing solution c, adding manganese oxyhydroxide with the molar ratio of 1.1 to lithium iron phosphate into the filtrate a, stirring for 2 hours at 40 ℃, wherein the pH value is 1, and precipitating and filtering out redundant oxidant;
(3) adding sodium hydroxide into the filtrate obtained in the step 2), adjusting the pH value to 1.9 to form iron phosphate precipitate, and filtering and separating filtrate d, wherein the recovery rate of the iron phosphate is 91.23%;
(4) continuously adding sodium hydroxide into the filtrate d in the step 3) to adjust the pH value to 10, aerating for 3 hours in air, oxidizing manganese salt to form manganese oxyhydroxide, filtering to obtain filter residue e and filtrate e, and recycling the filter residue e, namely the manganese oxyhydroxide after cleaning to the step 2);
(5) and adding sodium carbonate into the filtrate e at the reaction temperature of 100 ℃ for 2.5h and the stirring speed of 300rpm, heating and concentrating, and recovering to obtain the lithium carbonate. The recovery of lithium was 90.53%.
Example 3
The method for the novel oxidation lithium leaching of the waste lithium iron phosphate in the embodiment is basically the same as that of the embodiment 1, and the achieved effects are basically the same as that of the embodiment:
(1) mixing waste lithium iron phosphate powder, concentrated sulfuric acid and water in a weight ratio of 5: 3: 20, reacting for 1 hour, and filtering to obtain filtrate a and filter residue a, wherein the pH value of the filtrate is 0.7, and the leaching rates of phosphorus, iron and lithium reach 96%;
(2) washing and filtering the filter residue a obtained by the reaction in the step 1), circularly preparing slurry in the step 1 by using a washing solution c, adding manganese oxyhydroxide with the molar ratio of 1.2 to lithium iron phosphate into the filtrate a, stirring for 3 hours at 50 ℃, wherein the pH value is 0.95, and precipitating and filtering excessive oxidant;
(3) adding sodium hydroxide into the filtrate obtained in the step 2), adjusting the pH value to 2 to form iron phosphate precipitate, and filtering and separating filtrate d, wherein the recovery rate of the iron phosphate is 90.02%;
(4) continuously adding sodium hydroxide into the filtrate d in the step 3) to adjust the pH value to 11, aerating for 3 hours in air, oxidizing manganese salt to form manganese oxyhydroxide, filtering to obtain filter residue e and filtrate e, and recycling the filter residue e, namely the manganese oxyhydroxide after cleaning to the step 2);
(5) and adding sodium carbonate into the filtrate e at the reaction temperature of 100 ℃ for 2h and the stirring speed of 300rpm, heating and concentrating, and recovering to obtain the lithium carbonate. The recovery rate of lithium is 90.32%;
the above embodiments are merely illustrative of the technical concept and features of the present invention, and the purpose thereof is to enable those skilled in the art to understand the content of the present invention and implement the present invention, and not to limit the scope of the present invention, and all equivalent changes or modifications made according to the spirit of the present invention should be covered in the scope of the present invention.
Claims (8)
1. A novel method for oxidizing and leaching lithium of waste lithium iron phosphate is characterized in that an oxidant circulation process route is adopted, and when lithium is oxidized and leached, a reduced oxidant is activated by air or oxygen and then is reused for oxidizing and leaching lithium of the lithium iron phosphate, and the method comprises the following steps:
step S1, mixing waste lithium iron phosphate powder, concentrated sulfuric acid and pure water into slurry according to a certain proportion, reacting for a certain time, and filtering to obtain filtrate a containing lithium ions, ferrous ions and phosphate radicals and filter residue a containing carbon black and PVDF;
step S2, adding an oxidant namely manganese oxyhydroxide into the filtrate a obtained in the step S1, controlling the pH value to be 0-1, and performing precipitation and filtration to obtain filter residue containing redundant oxidant and filtrate b containing lithium ions, iron ions with valence III, manganese ions with valence II and phosphate radicals;
step S3, washing and filtering the filter residue a in the step S1, wherein the washing liquid contains lithium ions and the washing liquid is circulated back to the slurry preparation in the step S1;
step S4, adding a sodium hydroxide solution into the filtrate b obtained in the step S2, adjusting the pH value to form an iron phosphate precipitate, and filtering and separating filtrate d containing lithium ions and manganese ions and iron phosphate filter residues;
step S5, sodium hydroxide is continuously added into the filtrate d of the step S4 to adjust the pH value, manganese hydroxide precipitate is produced, manganese oxyhydroxide is formed through aeration oxidation, manganese oxyhydroxide slag and lithium-containing filtrate e are obtained through filtration, and the manganese oxyhydroxide slag is recycled to the step S2 after being cleaned;
and S6, heating and concentrating the filtrate e in the step S5, adding sodium carbonate while the filtrate is hot to precipitate lithium, and filtering and washing to obtain lithium carbonate.
2. The novel lithium leaching method for waste lithium iron phosphate oxide according to claim 1, wherein the particle size of the waste lithium iron phosphate powder in step S1 is 60-150 meshes, and the iron content is 30-35 wt.%, the lithium content is 3.5-4.5 wt.%, and the phosphorus content is 18-23 wt.%.
3. The novel lithium leaching method for waste lithium iron phosphate oxide as claimed in claim 2, wherein the waste lithium iron phosphate powder in step S1 further contains sodium, magnesium, nickel, aluminum, calcium, cobalt, and manganese.
4. The novel lithium leaching method for waste lithium iron phosphate oxide according to claim 1, wherein the weight ratio of waste lithium iron phosphate powder to concentrated sulfuric acid in step S1 is 5: 3, the proportion range of the waste lithium iron phosphate powder to the water is 1: 3-1: 5, the reaction time is 1-5 hours, and the pH value of the filtrate is controlled within the range of 0.3-0.8.
5. The novel method for oxidizing and leaching lithium of waste lithium iron phosphate according to claim 1, wherein in the step S2, the manganese oxyhydroxide is used as an oxidant, the lithium iron phosphate is in a molar ratio of 1-1.2, the temperature is 30-60 ℃, and the time is 2-5 hours; and oxidizing ferrous iron in the filtrate into ferric iron.
6. The novel method for oxidizing and leaching lithium of waste lithium iron phosphate according to claim 1, wherein sodium hydroxide is added in step S4 to adjust the pH to 1.9-2.2; and precipitating and recycling the iron phosphate.
7. The novel method for oxidizing and leaching lithium of waste lithium iron phosphate according to claim 1, wherein sodium hydroxide is continuously added in step S5 to adjust the pH to 9-11 for 1-3 hours, the aerated gas source is air or oxygen, and the aerated product is manganese oxyhydroxide serving as a recycled oxidant.
8. The novel waste lithium iron phosphate lithium oxidation leaching method according to claim 1, wherein in the step S6, the lithium precipitation reaction temperature is 100 ℃, the reaction time is 1-3 h, and the stirring speed is 200-300 rpm.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202111581434.1A CN114512737A (en) | 2021-12-22 | 2021-12-22 | Novel oxidation lithium leaching method for waste lithium iron phosphate |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202111581434.1A CN114512737A (en) | 2021-12-22 | 2021-12-22 | Novel oxidation lithium leaching method for waste lithium iron phosphate |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN114512737A true CN114512737A (en) | 2022-05-17 |
Family
ID=81547562
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202111581434.1A Withdrawn CN114512737A (en) | 2021-12-22 | 2021-12-22 | Novel oxidation lithium leaching method for waste lithium iron phosphate |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN114512737A (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN115385316A (en) * | 2022-09-23 | 2022-11-25 | 清华四川能源互联网研究院 | Recovery process of lithium iron phosphate |
| CN118198571A (en) * | 2024-05-16 | 2024-06-14 | 河北顺境环保科技有限公司 | Recycling method of lithium iron manganese phosphate battery anode material |
-
2021
- 2021-12-22 CN CN202111581434.1A patent/CN114512737A/en not_active Withdrawn
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN115385316A (en) * | 2022-09-23 | 2022-11-25 | 清华四川能源互联网研究院 | Recovery process of lithium iron phosphate |
| CN118198571A (en) * | 2024-05-16 | 2024-06-14 | 河北顺境环保科技有限公司 | Recycling method of lithium iron manganese phosphate battery anode material |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN113061723B (en) | Method for recovering lithium from waste lithium iron phosphate batteries and preparing iron phosphate | |
| CN107267759B (en) | Comprehensive recovery method of lithium ion battery anode material | |
| CN111129632B (en) | Method for recycling anode and cathode mixed materials of waste ternary lithium ion battery | |
| CN106848472B (en) | Method for recycling lithium from waste lithium iron phosphate batteries | |
| CN112897492B (en) | Method for regenerating and recycling high-impurity lithium iron phosphate waste powder | |
| CN110343864B (en) | Method for recovering lithium and cobalt in waste electrode material by microwave roasting assistance | |
| CN109626350B (en) | Method for preparing battery-grade iron phosphate from waste lithium iron phosphate battery positive plates | |
| CN106848473B (en) | Method for selectively recovering lithium in waste lithium iron phosphate batteries | |
| CN113880064B (en) | Method for treating high-impurity lithium iron phosphate waste powder by low-consumption phosphoric acid | |
| CN114512737A (en) | Novel oxidation lithium leaching method for waste lithium iron phosphate | |
| CN109179359A (en) | A method of extracting lithium and ferric phosphate from LiFePO4 waste material | |
| CN113793994B (en) | Method for recycling waste lithium iron phosphate batteries | |
| CN113816353B (en) | Method for removing aluminum in acid leaching solution of waste lithium iron phosphate battery by iron-aluminum coprecipitation | |
| CN113415793B (en) | Method for preparing high-purity iron phosphate from lithium iron phosphate battery waste | |
| CN113846219B (en) | Method for extracting lithium from waste lithium batteries | |
| CN113603120A (en) | Method for recovering battery-grade lithium from waste lithium iron phosphate through short-process acid leaching | |
| CN112342383A (en) | Method for separating and recovering nickel, cobalt, manganese and lithium in ternary waste | |
| CN116706302A (en) | Lithium battery recycling method | |
| CN115784188A (en) | Method for recycling and preparing battery-grade iron phosphate | |
| CN113666397A (en) | Method for economically recycling lithium from waste lithium iron phosphate material by acid process | |
| CN113735109B (en) | Method for recovering graphite from lithium ion battery and application thereof | |
| CN116397110B (en) | Method for recycling lithium from waste lithium iron phosphate battery | |
| CN117431414A (en) | Low-cost utilization method of low-lithium solution and nickel-cobalt intermediate product treatment solution | |
| CN117625996A (en) | Method for recycling lithium from lithium iron phosphate battery positive electrode waste powder | |
| CN115716653A (en) | Method for rapidly and directionally leaching lithium from lithium iron phosphate waste |
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 | ||
| WW01 | Invention patent application withdrawn after publication |
Application publication date: 20220517 |
|
| WW01 | Invention patent application withdrawn after publication |