222results about "Cobalt sulfates" patented technology

The invention discloses a method for recovering and separating nickel, cobalt and manganese from waste ternary lithium ion battery material lithium extraction slag, which comprises the following steps: pulping waste ternary battery material lithium extraction slag, leaching, introducing compressed air as an oxidant, and carrying out solid-liquid separation after leaching to obtain a leachate and leaching slag; sequentially performing copper removal, iron removal, aluminum removal and fluorine removal on the leachate to finally obtain fluorine-removed liquid; carrying out refined filtration on the fluorine-removed liquid to obtain a refined-filtered liquid; adjusting the pH value of the finely filtered liquid, and extracting impurities by using nickel soap P204 to obtain a rich organic phase and raffinate 1; extracting manganese from the raffinate 1 by using nickel soap P204 to obtain a manganese-rich organic phase and raffinate 2; extracting cobalt from the raffinate 2 by using nickel soap P507 to obtain a cobalt-rich organic phase and raffinate 3; and carrying out evaporative crystallization on the raffinate 3 to obtain nickel sulfate. The whole process has the advantages of short flow, high metal recovery rate, high product quality and low sodium-containing wastewater treatment capacity, and nickel, cobalt, manganese and lithium elements in the waste ternary lithium ion battery material are efficiently recycled by combining a front-end lithium extraction and recovery process, so that resource circulation is realized.

A treatment process for crystallizing a metal sulfate involving pre-treating a feedstock comprising calcium, magnesium, and / or lithium impurities, the pre-treating involving pre-leaching the feedstock in the presence of a lixiviant, selectively extracting a first portion of any of the impurities from the feedstock, and forming a leached solution comprising an uncrystallized metal sulfate and any remaining impurities; and / or refining the leached solution and removing a second portion of any of the remaining impurities; and crystallizing the uncrystallized metal sulfate from the leached solution to form a crystallized metal sulfate. So processed, the crystallized metal sulfate may be battery-grade or electroplating-grade.

The invention discloses electronic-grade cobaltous sulfate as well as a purification method and application thereof, and belongs to the technical field of chemical processes. The purification method of the electronic-grade cobalt sulfate comprises the following steps: S1, deoiling: deoiling a cobalt sulfate crude product solution through an adsorbent to obtain a cobalt sulfate deoiling solution; s2, ion exchange: purifying the cobalt sulfate deoiling liquid through an ion exchanger to obtain a cobalt sulfate purified liquid; and S3, recrystallization: carrying out evaporation concentration and cooling crystallization on the cobalt sulfate purified liquid, and controlling the crystal yield to be greater than 0 and less than or equal to 60% to obtain the electronic-grade cobalt sulfate crystal. According to the purification method, through the steps of oil removal, ion exchange and recrystallization and the combination of crystal yield control, impurities in the cobalt sulfate crude product solution can be effectively removed, the electronic-grade cobalt sulfate crystal and the electronic-grade cobalt sulfate solution which are low in total metal impurity content and low in total organic carbon content are obtained, and the electronic-grade cobalt sulfate crystal and the electronic-grade cobalt sulfate solution have stable and good use performance and are suitable for industrial production. And the method is particularly widely applied to the field of nanoscale chip integrated circuits.

The invention belongs to the technical field of waste battery recovery and regeneration, and particularly relates to a method for recovering valuable metal from a waste lithium battery positive electrode material. The method comprises the following steps: carrying out sulfuration roasting on waste positive electrode powder, selectively extracting lithium in a water leaching manner, and precipitating lithium to obtain lithium carbonate; separating and purifying the nickel, the cobalt and the manganese through microwave acid leaching, precipitation impurity removal and step-by-step extraction to obtain extract liquor of the nickel, the cobalt and the manganese, and performing reverse extraction on the extract liquor to obtain battery-grade cobalt sulfate, battery-grade nickel sulfate and battery-grade manganese sulfate. According to the method, lithium is extracted firstly, the influence of the lithium element on subsequent nickel-cobalt-manganese extraction is reduced, meanwhile, the recovery rate of lithium is increased through the water leaching method, and the recovery cost is reduced. According to the method, precipitation and impurity removal are performed before nickel-cobalt-manganese extraction, so that the content of impurities in a sulfate solution is reduced, and the recovery rate of nickel, cobalt and manganese is greatly improved.

The present disclosure provides a method of recovering a spent battery cathode material comprising lithium and at least one of nickel, cobalt and / or manganese, the method comprising: heating the spent battery cathode material in a reducing atmosphere to form a heat-treated spent battery cathode material comprising LiF and one or more of LijO, LiOH and LijCOs; washing the heat treated waste battery cathode material in an aqueous solvent to extract lithium-containing species and fluorine-containing species wherein the aqueous solvent is free of alkaline earth metal hydroxides or other species intended to reduce or prevent soluble fluorine species from remaining dissolved in the aqueous solvent; separating an aqueous solvent comprising lithium and fluorine species from the heat treated waste battery material; after separating an aqueous solvent comprising lithium and fluorine species from the heat-treated waste battery material, treating the aqueous solvent to separate lithium species from fluorine species; recycling a lithium substance in the form of lithium hydroxide or lithium carbonate; forming an acidic aqueous recovery feed comprising one or more of nickel, cobalt and / or manganese by leaching the heat treated waste battery cathode material with a mineral acid after the step of separating the aqueous solvent from the heat treated waste battery material; and recovering one or more of nickel, cobalt and / or manganese from the acidic aqueous recovery feed by a further process step selected from one or more of solvent extraction, solid phase extraction, electrochemical extraction and precipitation processes.

The invention relates to a battery material preparation technology, in particular to a method for preparing high-purity cobaltous sulfate from crude cobaltous hydroxide, which comprises the following steps: S1, reacting the crude cobaltous hydroxide with sulfuric acid to generate magnesium sulfate; s2, washing to remove magnesium; s3, adding sulfuric acid and hydrogen peroxide into the crude cobalt hydroxide after magnesium washing; adding crude cobalt hydroxide to adjust the pH value to obtain a purified solution; s4, adding sodium fluoride into the purified liquid, and filtering after reaction to obtain filtrate; s5, saponifying with sodium hydroxide by using an acidic extractant, then performing soap conversion by using a cobalt sulfate solution, extracting manganese in the filtrate by using an obtained organic phase, and then performing reverse extraction on the organic phase by using sulfuric acid to obtain a manganese sulfate solution; s6, the raffinate obtained after manganese extraction is introduced into an adsorption tower loaded with a zirconium-based composite fluorine adsorbent; and S7, concentrating and crystallizing the defluorinated solution. According to the method, the zirconium-based composite fluorine adsorbent is introduced to be coupled with the process, fluorine ions can be removed, and cobalt loss caused by cobalt fluoride precipitation and the influence of the fluorine ions on the quality of a cobalt sulfate product are avoided.

A waste battery processing method includes a discharging process of discharging a waste battery, a dismantling process of dismantling the discharged waste battery into battery cell units, a shredding process of shredding the dismantled waste battery, a roasting process of roasting the shredded waste battery, a pulverizing process of pulverizing the fired waste battery, and a hydrometallurgical process of extracting and recovering metals from the pulverized waste battery.

The invention provides a doubling treatment method of battery black powder and nickel cobalt hydroxide. The doubling treatment method comprises the following steps: carrying out reduction roasting and water immersion treatment on the battery black powder to obtain a first lithium-containing liquid and a solid product; carrying out acid leaching on the solid product to obtain a leaching solution; after removing impurities from the leachate, extracting the leachate with a first saponification extraction agent to obtain first raffinate and a first extraction organic phase; carrying out soap conversion reaction on the first raffinate and a second saponification extraction agent to obtain a second extracted and soap-converted organic phase and a second lithium-containing liquid; carrying out acid leaching and impurity removal on nickel cobalt hydroxide, and carrying out extraction reaction on the solution and the second extraction soap-converted organic phase to obtain a second extraction organic phase and a second raffinate; the second raffinate is subjected to Co extraction, Mg extraction and evaporative crystallization, and nickel sulfate is obtained; and the organic phase obtained after Co extraction is subjected to back extraction and evaporative crystallization, and cobalt sulfate is obtained. Compared with a traditional doubling treatment technology, the doubling treatment method avoids the problem of impurity pollution caused by doubling treatment of traditional battery black powder and nickel cobalt hydroxide raw materials.

In one aspect, a preparation method of iron phosphate includes: mixing pyrite cinder and an sulfite evenly in water to obtain a first mixed system; adding phosphoric acid and a buffer to the first mixed system to perform a leaching reaction; performing a first solid-liquid separation on a slurry obtained from the leaching reaction to obtain a first filtrate and a first residue; introducing air into the first filtrate and then performing a first stirring reaction on the first filtrate; performing a second solid-liquid separation on a slurry obtained from the first stirring reaction to obtain a second filtrate and a second residue; and calcining the second residue to obtain iron phosphate.

The present disclosure relates to methods for recovering metals from used lithium-ion batteries and related electronic wastes. The methods provide modular, inexpensive, and energy efficient means for recovering up to 99.9% pure lithium, nickel, cobalt, and manganese in the form of various oxides or salts, e.g., phosphates, sulfates, or hydroxides. The methods produce nearly zero waste, as many of the recovered waste products can be purified and / or recycled.

The invention relates to a method for recovering nickel and cobalt from a mixture of compounds of these metals from the recycling of spent lithium-ion batteries, comprising the following steps: a) digestion of a mixture of nickel and cobalt compounds in a solution containing hydrochloric acid having a concentration of more than 25 mass %, in case the mixture of nickel and cobalt compounds is solid; or bringing the mixture of nickel and cobalt compounds to a hydrochloric acid concentration of more than 25 mass %, in case the mixture of nickel and cobalt compounds is a solution; b) activation of ion-exchange resin in a column using hydrochloric acid; c) passing the solution from step a) through the column filled with the ion-exchange resin activated in step b); d) washing the column with hydrochloric acid having a concentration of more than 25 mass % in order to wash out the remaining solution containing nickel ions; e) washing the column with hydrochloric acid having a concentration of less than 10 mass % in order to wash out cobalt ions; f) extraction distillation of the nickel ion solution obtained in step d) in hydrochloric acid using sulfuric(VI) acid; phase separation in a spent liquid; recycling of a filtrate to distillation; dissolution of nickel sulfate(VI) and electrolysis in order to recover metallic nickel; g) extraction distillation of the cobalt ion solution obtained in step e) in hydrochloric acid using sulfuric(VI) acid; phase separation in a spent liquid; recycling of a filtrate to distillation; dissolution of cobalt sulfate(VI) and electrolysis in order to recover metallic cobalt; h) extraction distillation of the solution of diluted hydrochloric acid with nickel and cobalt ions obtained after the activation of the ion-exchange resin in step b), using sulfuric(VI) acid; phase separation in a spent liquid; recycling of a filtrate to distillation; recycling of a mixture of the formed cobalt sulfate(VI) and nickel sulfate(VI) to digestion in step a); i) rectification of diluted hydrochloric acid having a concentration below the azeotropic concentration (approx. 20.2 mass % at atmospheric pressure) formed in extraction distillation processes in steps f)-h) in order to concentrate hydrochloric acid and recover and recycle of water; recycling of concentrated hydrochloric acid to extraction distillation in steps f)-h).

The method for preparing nickel sulfate according to an exemplary embodiment may prepare a nickel-containing raw material. Nickel may be selectively leached from a nickel-containing feedstock using an oxidant to produce a first leachate. Residual metals may be separated from the first leachate to produce a second leachate. Nickel sulfate may then be obtained from the second leachate. Therefore, a separate nickel extraction step can be omitted, thereby reducing unnecessary by-products.

The invention provides a method for comprehensively recovering lithium and cobalt from a waste lithium cobalt oxide battery positive electrode material, which comprises the following steps: (1) pretreating the waste lithium cobalt oxide battery positive electrode material to obtain a lithium cobalt oxide positive electrode active material; uniformly mixing the lithium cobalt oxide positive active material with a sulfenyl compound and a carbon source to obtain a mixture; the mixture is subjected to inert atmosphere roasting, grinding, leaching and filtering in sequence, and a lithium-containing solution and sulfur-containing filter residues are obtained; (2) carrying out acid leaching impurity removal on the sulfur-containing filter residues, and filtering to obtain cobalt sulfide residues; (3) roasting the cobalt sulfide slag in an oxygen atmosphere to obtain a roasted product; and (4) the roasted product is leached and filtered, and a cobalt sulfate solution and cobaltosic oxide are obtained. According to the method, soluble sulfate and high-purity cobalt oxide can be obtained, and the method is short in process, low in cost and high in lithium selectivity.

The invention provides a new process for comprehensively recovering valuable metals in ternary positive electrode material powder, which comprises the steps of positive electrode material powder dissolution, metal salt separation, extraction and reverse extraction, lithium salt treatment and the like, acid obtained by electrolysis can be recycled, and a lithium salt solution can be further used for preparing a lithium carbonate product. The process has the remarkable advantages that resource recovery is comprehensive and efficient, the valuable metal recovery rate is high, and the metal separation precision is high; the process is environment-friendly and low in cost, auxiliary materials are recycled, the cost is reduced, and environmental pollution is reduced; the product is excellent in quality, low in impurity content and stable in performance, can meet high-end market requirements, and improves the market competitiveness and the added value. The process has outstanding advantages in the aspects of resource recovery, environmental protection cost, product quality and the like, and has wide application prospects and market values.

A method of preparing a cathode active material composition involves combining a first cathode active material including recycled lithium 40 with a second cathode active material 41; wherein the ratio

The invention relates to the technical field of positive electrode precursors, in particular to a method for preparing a sulfate solution for a precursor by using a cobalt nickel hydroxide intermediate product and application of the sulfate solution. Performing acid leaching on the intermediate product, and then adding a flocculating agent to obtain a cobalt-nickel-manganese mixed solution and manganese slag; extracting the cobalt-nickel-manganese mixed solution and P507-C272, and reversely extracting a loaded organic phase to obtain a crude manganese sulfate solution; performing P204 impurity removal on the raffinate, recovering cobalt by using P507 to obtain a cobalt sulfate solution, and performing C272 nickel-magnesium separation to obtain a nickel sulfate solution; manganese slag is subjected to reduction leaching to obtain reduction leaching liquid, and then the reduction leaching liquid is mixed with a sodium carbonate solution to remove iron to obtain iron-removed liquid; mixing the iron-removed solution with the crude manganese sulfate solution, and removing calcium and magnesium to obtain a calcium-magnesium-removed solution; mixing the calcium and magnesium removed solution with an aluminum source to remove fluorine to obtain a fluorine removed solution; and mixing the fluorine-removed solution with sulfide to remove copper and zinc, adding alkali liquor to obtain a heavy-removed solution, and treating the heavy-removed solution with modified resin to obtain a refined manganese sulfate solution. The method is high in manganese recovery rate and low in treatment cost.

The present invention discloses a method for preparing a sodium-ion battery cathode material from lithium-ion battery recycling materials, belonging to the field of battery technology. The method comprises the following steps: separating nickel and / or manganese contained in the lithium-ion battery recycling materials, and then preparing a precursor of the sodium-ion battery cathode material together with raw materials providing the remaining elements according to the elemental composition in the molecular formula of the preset sodium-ion battery cathode material. Further, the precursor of the sodium-ion battery cathode material is sintered and modified with a sodium source to obtain the sodium-ion battery cathode material. This method can greatly reduce the preparation cost of the sodium-ion battery cathode material and can form good resource recycling and green production.

The utility model relates to the technical field of cobalt-nickel salt extraction and separation, and discloses an efficient cobalt-nickel salt extraction and separation device which comprises a support, an extraction tank is fixedly connected to the middle of the support, a transverse plate is fixedly connected to the upper portion of the extraction tank, a motor is arranged on the rear side of the outer portion of the transverse plate, and the output end of the motor is fixedly connected with a rotating disc. And a fixed rod is fixedly connected to the outer portion of the rotary disc, the fixed rod is sleeved with a reciprocating rod, guide rings are fixedly connected to the two sides of the outer portion of the transverse plate, the reciprocating rod is slidably connected to the interiors of the two guide rings, and a connecting rod is fixedly connected to the lower portion of the reciprocating rod. According to the extraction tank disclosed by the utility model, in the extraction process, the upper and lower different areas in the extraction tank can be conveniently stirred, uniform distribution of materials in the extraction tank is ensured, contact between cobalt and nickel and a leaching agent can be accelerated, and the extraction efficiency is improved while the reaction rate is improved.

The present invention provides a method for comprehensively recovering lithium and cobalt from the cathode material of waste lithium cobalt oxide batteries, comprising the following steps: (1) Pretreating the cathode material of waste lithium cobalt oxide batteries to obtain lithium cobalt oxide cathode active material; mixing the lithium cobalt oxide cathode active material evenly with a sulfur-based compound and a carbon source to obtain a mixed material; subjecting the mixed material to roasting in an inert atmosphere, grinding, leaching, and filtering in sequence to obtain a lithium-containing solution and a sulfur-containing filter residue; (2) Subjecting the sulfur-containing filter residue to acid leaching for impurity removal and filtering to obtain cobalt sulfide slag; (3) Roasting the cobalt sulfide slag in an oxygen atmosphere to obtain a roasted product; (4) Subjecting the roasted product to leaching and filtering to obtain a cobalt sulfate solution and cobalt tetroxide. The method of the present invention can obtain soluble sulfates and high-purity cobalt oxides, and has a short process flow, low cost, and high lithium selectivity.

The invention belongs to the technical field of hydrometallurgy, and discloses a method for preparing nickel sulfate and cobalt sulfate from nickel feed liquid. The method comprises the following steps: 1) carrying out first extraction on the nickel feed liquid by using a nickel-cobalt extraction agent to obtain a first organic phase and first raffinate; 2) washing the first organic phase with a first washing solution, wherein the first washing solution comprises sulfuric acid and nickel sulfate; (3) the washed first organic phase is subjected to reverse extraction, and a first regenerated organic extraction agent and nickel-cobalt enrichment liquid are obtained; 4) performing second extraction on the nickel-cobalt enriched liquid by using an impurity extracting agent to obtain a second organic phase and a mixed solution of nickel sulfate and cobalt sulfate; 5) washing the second organic phase by using a sulfuric acid solution, and 6) carrying out reverse extraction on the washed second organic phase to obtain a reverse extraction solution and a second regenerated organic extracting.By adopting the method provided by the invention, nickel and cobalt enrichment can be realized from the high-calcium-magnesium solution, impurity ions can be effectively removed, the process is simple, and the cost is low.

The invention provides a hexammine cobalt salt and a preparation method thereof. The chemical formula of the hexammine cobalt salt is [Co (NH3) 6] [HSO4] [SO4]. The invention also provides an application of the carbon dioxide absorption liquid in carbon dioxide gas absorption, a carbon dioxide gas absorption liquid and a method for absorbing carbon dioxide gas. The invention also provides a crystalline clathrate compound of carbon dioxide and hexammine cobalt salt and a method for releasing carbon dioxide molecules from the clathrate compound.

The present invention discloses an electronic-grade cobalt sulfate and its purification method and application, belonging to the field of chemical process technology. The electronic-grade cobalt sulfate purification method of the present invention comprises the following steps: S1, deoiling: deoiling a crude cobalt sulfate solution through an adsorbent to obtain a deoiled cobalt sulfate solution; S2, ion exchange: purifying the deoiled cobalt sulfate solution through an ion exchanger to obtain a purified cobalt sulfate solution; S3, recrystallization: evaporating and concentrating the purified cobalt sulfate solution, cooling and crystallizing it, and controlling the crystal yield to be greater than 0 and less than or equal to 60%, to obtain electronic-grade cobalt sulfate crystals. The purification method of the present invention can effectively remove impurities in the crude cobalt sulfate solution through the steps of deoiling, ion exchange and recrystallization, combined with the control of the crystal yield, to obtain electronic-grade cobalt sulfate crystals and an electronic-grade cobalt sulfate solution with low total metal impurity content and low total organic carbon content. The electronic-grade cobalt sulfate crystals and the electronic-grade cobalt sulfate solution have stable and good performance, and are particularly widely used in the field of nano-chip integrated circuits.

Provided is a method for separating impurities and cobalt without using an electrolysis process from a cobalt chloride solution containing impurities and producing a high purity cobalt sulfate. The production method for cobalt sulfate includes: a copper removal step (S1) of adding a sulfurizing agent to a cobalt chloride solution containing one or more impurities of copper, zinc, manganese, calcium, and magnesium and generating a precipitate of sulfide of copper to separate to remove copper; a neutralization step (S2) of adding a neutralizer or a carbonation agent to a cobalt chloride solution having undergone through the copper removal step (S1) and generating cobalt hydroxide or basic cobalt carbonate to separate magnesium; a leaching step (S3) of adding sulfuric acid to the cobalt hydroxide or the basic cobalt carbonate to obtain cobalt sulfate solution; and a solvent extraction step (S4) of bringing an organic solvent containing an alkyl phosphoric acid-based extractant to the cobalt sulfate solution and extracting zinc, manganese, and calcium into the organic solvent to separate to remove zinc, manganese, and calcium. These steps are sequentially executed.

A treatment process for crystallizing a metal sulfate involving pre-treating a feedstock comprising calcium, magnesium, and / or lithium impurities, the pre-treating involving pre-leaching the feedstock in the presence of a lixiviant, selectively extracting a first portion of any of the impurities from the feedstock, and forming a leached solution comprising an uncrystallized metal sulfate and any remaining impurities; and / or refining the leached solution and removing a second portion of any of the remaining impurities; and crystallizing the uncrystallized metal sulfate from the leached solution to form a crystallized metal sulfate. So processed, the crystallized metal sulfate may be battery-grade or electroplating-grade.

To provide a method for producing cobalt chloride having high purity, by separating impurities and cobalt from a cobalt chloride solution including impurities without using an electrolysis process.SOLUTION: A method for producing cobalt sulfate sequentially executes: a copper removal step S1 of adding a sulfating agent to a cobalt chloride solution including impurities, and separating and removing copper; a first solvent extraction step S2 of bringing an organic solvent including an alkyl phosphate-based extraction agent into contact with the cobalt chloride solution, and extracting zinc, manganese and calcium into the organic solvent, and separating and removing the zinc, manganese and calcium; a second solvent extraction step S3 of adding a sodium carbonate solution or sodium hydrogencarbonate solution to the cobalt chloride solution, thereby adjusting pH to 5.0-7.0, bringing an organic solvent including a carboxylic acid-extraction agent into contact with the cobalt chloride solution, extracting cobalt, then performing back extraction on the cobalt with a sulfuric acid, thereby obtaining a cobalt chloride solution; and a crystallization step S4 of crystallizing the cobalt chloride solution obtained through the second solvent extraction step S3. The method enables direct production of cobalt sulfate having high purity without using an electrolysis process.SELECTED DRAWING: Figure 1

The invention discloses a method for purifying metal impurities in cobaltous sulfate, a pure cobaltous sulfate product and application of the pure cobaltous sulfate product, and the purification method comprises the following steps: 1) evaporating a cobaltous sulfate aqueous solution to a supersaturated state, cooling and crystallizing, and heating; and 2) carrying out solid-liquid separation to obtain crystals and mother liquor. By adopting the purification method disclosed by the invention, the content of each metal impurity in the cobaltous sulfate is reduced to be below 100ppb, and the use requirements of the electroplating liquid for cobalt interconnection of the integrated circuit are met.

The present disclosure relates to systems and methods for electrically conductive membrane separation from a mixture solution via membrane nanofiltration, electro-filtration, or electro-extraction by: generating an electric field at the membrane filter, holding the membrane filter at a constant electric potential, or driving a constant current through the membrane filter; feeding a mixture solution through the membrane nanofiltration system; and separating a component from the mixture solution into a permeate solution.

Provided is a method for separating impurities and cobalt without using an electrolysis process from a cobalt chloride solution containing impurities and producing a high purity cobalt sulfate. The production method includes: a first solvent extraction step (S1) of bringing an organic solvent containing an alkyl phosphoric acid-based extractant into contact with a cobalt chloride solution containing impurities, and extracting zinc, manganese, and calcium into the organic solvent to separate to remove zinc, manganese, and calcium; a copper removal step (S2) of adding a sulfurizing agent to a cobalt chloride solution and generating a precipitate of sulfide of copper to separate to remove copper; a second solvent extraction step (S3) of bringing an organic solvent containing a carboxylic acid-based extractant into contact with a cobalt chloride solution and back extracting cobalt with sulfuric acid after extracting cobalt into the organic solvent to obtain cobalt sulfate solution; and a crystallization step (S4) of the cobalt sulfate solution obtained after having undergone through the second solvent extraction step (S3). These steps are sequentially executed. Without using an electrolysis process, a high purity cobalt sulfate is directly produced by separating cobalt and impurities containing manganese.

To provide a method for recovering lithium from a waste lithium ion battery that enables lithium to be recovered with a high recovery rate and also enables salts generated during the recovery process to be reused in the process as mineral acid and alkali.SOLUTION: A method for recovering lithium from a waste lithium ion battery includes: a dissolution step for dissolving active material powder, obtained by pretreating a waste lithium ion battery, with mineral acid; an alkali hydroxide addition step for adding alkali to a solution obtained in the dissolution step; a solid-liquid separation step for performing solid-liquid separation into insoluble matter and a solution A, following the alkali hydroxide addition step; an extraction step for sequentially extracting manganese, nickel and cobalt in the solution A; a separation step for separating a lithium salt or the like from an alkali mixed salt aqueous solution obtained in the extraction step; and a lithium recovery step for recovering lithium from a lithium salt aqueous solution obtained in the separation step.SELECTED DRAWING: None