CN110938743B

CN110938743B - Method for extracting lithium and nickel and cobalt from waste lithium ion battery step by step

Info

Publication number: CN110938743B
Application number: CN201911036367.8A
Authority: CN
Inventors: 蒋训雄; 张贤; 赵峰; 李达
Original assignee: BGRIMM Technology Group Co Ltd
Current assignee: BGRIMM Technology Group Co Ltd
Priority date: 2019-10-29
Filing date: 2019-10-29
Publication date: 2022-01-28
Anticipated expiration: 2039-10-29
Also published as: CN110938743A

Abstract

The invention discloses a method for extracting lithium and nickel and cobalt from waste lithium ion batteries step by step, and belongs to the technical field of comprehensive recovery of lithium ion battery materials. The invention carries out reduction roasting on anode material powder obtained by splitting, crushing and screening waste lithium ion batteries by using a carbonaceous reducing agent, the obtained roasted product is mixed with water to be slurry, a proper amount of calcium chloride or lime milk solution is added for reaction and transformation, and lithium carbonate in the roasted product is selectively extracted into the solution, thereby realizing the separation from nickel, cobalt, manganese, iron, aluminum, phosphorus and the like. The method can realize preferential selective extraction of lithium, the obtained lithium solution has high purity and lithium concentration, extraction, impurity removal and evaporation concentration processes are not needed, the lithium recovery and product preparation processes are simple, the recovery rate is high, the energy consumption is low, and the environmental problem of high-concentration sodium salt wastewater does not exist.

Description

Method for extracting lithium and nickel and cobalt from waste lithium ion battery step by step

Technical Field

The invention belongs to the technical field of lithium ion battery material recovery, relates to a method for recovering lithium and nickel and cobalt from waste lithium ion battery materials step by step, and particularly relates to a method for transforming and preferentially extracting lithium by using salt substances after reducing and roasting a positive electrode material of a waste lithium ion battery.

Background

Lithium is a core raw material of lithium ion batteries, and with the rapid increase of the yield of new energy materials represented by the lithium ion batteries, the global demand for lithium is also rapidly increased. Lithium ore resources can be divided into two types, lithium ore and lithium brine. The lithium ion battery is mainly added into salt lake brine and granite pegmatite deposits, wherein the salt lake brine lithium accounts for 66% of the world lithium reserves and more than 80% of the reserve basis, and is the main source of the world lithium at present. Because the lithium extracted from the salt lake is a byproduct in the production of the potash fertilizer, the expansion of the yield of the lithium salt is limited, and the price of the lithium salt is further increased. Therefore, it is very important to recover lithium from the waste lithium ion battery.

In the lithium ion battery, lithium is a main component of a positive active material, and the positive active material is divided into a metal oxide positive material and a phosphate positive material, wherein the metal oxide positive material comprises lithium cobalt oxide, lithium nickel oxide, lithium manganese oxide, lithium iron oxide, lithium vanadium oxide, lithium cobalt nickel manganese oxide, lithium cobalt nickel aluminum oxide and the like; the phosphate anode material comprises lithium iron phosphate, lithium vanadium phosphate, lithium manganese phosphate, lithium cobalt phosphate, lithium vanadium phosphate and the like. In addition, lithium is also an important component of the electrolyte and the negative electrode active material, such as lithium hexafluorophosphate, lithium titanate and the like.

In the method for treating the anode material of the waste lithium ion battery, the recovery process based on the hydrometallurgy is relatively mature, and the application in the industry is relatively wide. In the existing hydrometallurgy, the anode material is almost leached by directly using acid and a reducing agent, or the anode active material is leached by using acid after being pretreated.

CN107196004A discloses a method for recovering valuable metals from waste power lithium ion power batteries, which is to calcine and crush positive plates of waste power lithium ion batteries in nitrogen atmosphere to obtain mixed powder, then add sulfuric acid and hydrogen peroxide to leach, neutralize and extract leachate to remove iron, aluminum, nickel, cobalt, manganese, etc., and add solid sodium carbonate to precipitate and recover lithium carbonate.

CN101519726A discloses a method for recovering valuable metals by roasting waste lithium ion batteries, which is mainly characterized in that lithium cobaltate anode materials are roasted and degummed at 500-850 ℃, then mixed with concentrated sulfuric acid and sulfate for size mixing, and subjected to secondary roasting at 350-600 ℃ in an electric furnace to convert metals such as copper, cobalt and the like into water-soluble sulfate, copper and cobalt are extracted and recovered, and then sodium carbonate is used for precipitating lithium.

CN108123185A discloses a method for recovering valuable metals in waste lithium manganate batteries, which comprises the steps of mixing a lithium manganate battery anode material subjected to disassembly and grinding with a proper amount of carbon powder, then carrying out reduction roasting, adding water into the roasted material for slurrying, dropwise adding hydrochloric acid, sulfuric acid or nitric acid and the like for leaching, filtering to obtain a filtrate, adjusting the pH value to 7.0-10.0 by using sodium hydroxide, filtering to remove impurities, then adding soluble carbonate, and precipitating lithium carbonate.

CN107017443A discloses a method for comprehensively recovering valuable metals from waste lithium ion batteries, which comprises the steps of carrying out discharge treatment on waste batteries, then crushing the waste batteries, carrying out pre-roasting at 300-400 ℃, and then adding a carbonaceous reducing agent or CO to carry out reduction roasting at 450-700 ℃. And (3) leaching the roasted fine material by using water, introducing carbon dioxide for carbonation leaching, and evaporating and crystallizing the leaching solution to produce a lithium carbonate product.

CN106129511A discloses a method for recovering valuable metals from waste lithium ion battery materials, which comprises the steps of mixing a waste lithium ion battery anode material with a reducing agent, carrying out reduction roasting treatment at the temperature of 500-750 ℃, and soaking roasted products in CO2 carbonated water to obtain a lithium bicarbonate aqueous solution which can be used for preparing Li₂CO₃Producing a product; the leaching residue is leached by oxidation acid or oxidation ammonia to leach valuable elements such as cobalt, nickel, manganese and the like, and corresponding compound products are prepared after extraction and purification.

CN110029225A discloses a method for recovering valuable metals from waste ternary lithium ion battery anode materials, which comprises the step of carrying out medium-temperature oxidizing roasting on the anode materials, wherein the roasting temperature is 700 ℃, and the roasting time is 60min, so as to obtain roasted products. And dissolving the roasted product in an ammonia-ammonium salt system with the ammonia concentration of 5mol/L, putting the ammonia-ammonium salt system into an autoclave, adding hydrazine hydrate serving as a reducing agent, and reacting in the autoclave for 120 min. Filtering and washing to obtain leaching slag and leaching liquid containing lithium, nickel, cobalt, manganese, iron, aluminum and copper.

CN107267759A discloses a comprehensive recovery method of a lithium ion battery anode material, which comprises the steps of carrying out high-temperature pretreatment on lithium iron phosphate and the anode material of a ternary battery; adding water for pulping; adding concentrated sulfuric acid and hydrogen peroxide, and filtering to remove insoluble substances; adding iron powder, filtering to remove copper element, and heating to generate iron-alumen-based slag; adding a calcium chloride solution, and filtering to remove phosphate radicals; extracting with extractant P204 in series and countercurrent to remove Fe and Ca impurities, extracting with extractant P507 in series and countercurrent to separate Ni, Co and Mn elements from Li element; carrying out back extraction on the organic phase by adopting sulfuric acid to obtain Ni, Co and Mn solutions, and realizing the recovery of nickel, cobalt and manganese; and concentrating the water phase, and adding a saturated sodium carbonate solution to generate lithium carbonate precipitate.

No matter direct reduction acid leaching or acid leaching after pretreatment, lithium in the positive electrode material and metals such as iron, cobalt, manganese, nickel, aluminum and the like in the positive electrode material are leached simultaneously, and then purification processes such as removing iron and aluminum by neutralization precipitation, removing nickel, cobalt, copper and manganese by extraction and the like are required to be carried out, and then lithium is recovered by carbonate precipitation, so that the lithium recovery process is long and the recovery rate is low; because almost all metals in the anode material are dissolved out, the concentration of lithium ions in the leaching solution is low, and the requirement of carbonate for precipitating lithium can be met only by a large amount of evaporation and thickening; because the nickel, cobalt, copper and the like are removed by extraction, the concentration of sodium ions in the purified lithium solution is high, the purity of lithium salt products is influenced, and the environmental problem of high-salinity wastewater exists. In addition, the anode powder after reduction roasting is subjected to water leaching and carbonation leaching by introducing carbon dioxide, which still belongs to weak acid leaching, so that impurities such as nickel, cobalt, iron, manganese, aluminum and the like are difficult to completely remove, and the problems of low leaching speed and low leaching rate of lithium exist due to the influence of the dissolution speed of carbon dioxide in water.

Disclosure of Invention

Aiming at the defects in the prior art, the invention aims to provide a method for extracting lithium and nickel and cobalt from waste lithium ion batteries step by step, the method comprises the steps of carrying out reduction roasting on a lithium-containing anode material stripped from the waste lithium ion batteries to obtain roasted sand, then using water for size mixing under the condition of not adding acid, adding a transformation agent for transformation, carrying out transformation extraction on lithium into a solution, and leaving impurities such as iron, cobalt, nickel, manganese, phosphorus and the like in transformation slag, thereby realizing preferential extraction of the lithium. And removing a small amount of excessive metal ions such as calcium, magnesium and the like in the solution obtained after transformation by adding a proper amount of lithium phosphate, lithium carbonate or calcine for replacement, and further obtaining a pure lithium solution for producing a lithium product. The transfer agent used in the transfer lithium extraction is one or more of calcium chloride, lime milk, magnesium chloride, magnesium sulfate, manganese chloride, manganese sulfate, ferrous chloride, ferrous sulfate, ferric chloride and ferric sulfate, preferably calcium chloride or lime milk or the mixture of the calcium chloride and the lime milk.

The purpose of the invention is realized by the following technical scheme.

The method for extracting lithium and nickel and cobalt from the waste lithium ion battery step by step is characterized by comprising the following steps of:

(1) reduction roasting: carrying out reduction roasting on a lithium-containing material obtained by disassembling, crushing and screening from a waste lithium ion battery to obtain roasted sand;

(2) transformation and lithium extraction: and (2) mixing the calcine obtained in the step (1) with water to obtain slurry, adding a proper amount of transformation agent to perform transformation and lithium extraction, and performing solid-liquid separation to obtain a lithium-containing solution and transformation slag. The transformation agent is one or more of calcium chloride, lime milk, magnesium chloride, magnesium sulfate, manganese chloride, manganese sulfate, ferrous chloride, ferrous sulfate, ferric chloride and ferric sulfate.

Further, the lithium-containing material is a lithium ion battery positive electrode active material.

Furthermore, the lithium-containing material is a positive electrode active material of the lithium ion battery and at least contains one or more of lithium cobaltate, lithium nickelate, lithium manganate, lithium nickel cobalt manganese, lithium nickel cobalt aluminate and lithium vanadate.

Further, the reducing roasting in the step (1) is roasting by adopting a reducing agent containing carbon, wherein the reducing agent containing carbon is one or more of coal powder, natural gas, carbon monoxide, coke powder, carbon powder, graphite and biomass.

Furthermore, the carbonaceous reducing agent used in the reduction roasting in the step (1) is one or more of natural gas, carbon monoxide, coke powder and carbon powder.

The roasting temperature of the reduction roasting is 500-1100 ℃, and preferably 550-850 ℃.

Preferably, the transformation agent in the step (2) is one or two of calcium chloride and lime milk.

Particularly, the method does not need to add acid when transforming and extracting the lithium, and controls the pH value of the solution to be more than or equal to 5; even if a small amount of acid is added, the pH value of the solution should be controlled to be more than or equal to 5.

Preferably, the transformation and lithium extraction in the step (2) is carried out in a stirring mill or a dissolution mill.

Further, in some embodiments, steps (3), (4), (5) are also included:

(3) removing impurities: adding a proper amount of lithium salt into the lithium-containing solution obtained in the step (2), stirring for a period of time, wherein the lithium salt is one or a mixture of more of the calcine, lithium phosphate and lithium carbonate obtained in the step (1), and then filtering to obtain a pure lithium solution;

(4) and (3) precipitating lithium: adding a proper amount of carbonate solution or phosphate solution into the pure lithium solution obtained in the step (3), stirring, and filtering to obtain lithium carbonate or lithium phosphate products;

(5) recovering nickel and cobalt: leaching the transformation slag obtained in the step (2) by using an ammonia solution or an acid solution, and recovering nickel and cobalt.

The invention discloses a method for extracting lithium and nickel and cobalt from waste lithium ion batteries in a distributed manner, which has the following basic principle:

reduction roasting: the method is characterized in that the difference of reduction difficulty degrees of metal oxides such as nickel, cobalt, manganese, iron, lithium, aluminum and the like in the anode material under the condition of carbon-containing reduction roasting is utilized to reduce the nickel, the cobalt and the iron into simple substance metal, one part of the manganese is reduced into metal, the other part of the manganese is reduced into MnO, the aluminum and the lithium are not reduced, wherein the aluminum still exists in the form of oxide, the lithium is converted into Li₂CO₃. For example, the lithium cobaltate positive electrode material is prepared by the following main reactions:

4LiCoO₂+3C＝2Li₂CO₃+4Co+CO₂

transformation and lithium extraction: the invention takes the water solution of metal salts such as calcium chloride, lime milk, magnesium chloride, magnesium sulfate, manganese chloride, manganese sulfate, ferrous chloride, ferrous sulfate, ferric chloride, ferric sulfate and the like as a transformation agent, acid substances are not added during transformation, metals such as nickel, cobalt, iron, manganese and the like, manganese oxide and aluminum oxide in calcine are not dissolved under the condition of transformation medium, and are remained in slag. The lithium carbonate in the calcine is converted into calcium, magnesium, manganese or iron carbonate with smaller solubility product, thereby realizing the selective dissolution of lithium. The carbonate solubility products of lithium, calcium, magnesium, manganese, iron are given in the following table:

compound (I)	Li₂CO₃	CaCO₃	MgCO₃	MnCO₃	FeCO₃
						Solubility product, K_sp	1.7×10^-3	8.7×10^-9	2.6×10^-5	9×10^-11	2×10^-11

Taking a calcium chloride transformation agent as an example, the reaction for transforming and extracting lithium is as follows:

Li₂CO₃+CaCl₂＝CaCO₃↓+2LiCl

the invention has the following effects: the invention discloses a method for distributing and extracting lithium and nickel and cobalt from waste lithium ion batteries, which comprises the steps of carrying out reduction roasting on a lithium-containing anode material, wherein nickel, cobalt, manganese, iron and the like are reduced into metal or divalent oxides, lithium is converted into lithium carbonate, then adding a calcium-containing transformation agent under the condition of water slurry mixing, converting the lithium carbonate into insoluble calcium carbonate and the like, lithium is replaced to obtain lithium-containing transformation liquid, impurities such as iron, cobalt, nickel, manganese, phosphorus, aluminum and the like are remained in transformation slag, realizing the selective preferential extraction of lithium, further realizing the separation of lithium from various impurities such as iron, cobalt, nickel, manganese, phosphorus and the like, and simplifying the recovery process of lithium. Because the transformation lithium extraction selectivity is high, the transformation lithium extraction can be carried out by adopting a smaller liquid-solid ratio, so that the lithium concentration in the solution is improved, the carbonate can be directly used for precipitating lithium without evaporation concentration, and the lithium recovery energy consumption can be greatly reduced. And because the transformed lithium-containing solution does not need extraction and impurity removal operation, the problems of treatment and environment of high-concentration sodium salt wastewater in comprehensive recovery of waste lithium ion batteries are avoided. The method has the advantages of short lithium recovery process, low energy consumption, high recovery rate and the like, and avoids the environmental problem of high-salinity wastewater.

Drawings

FIG. 1 is a schematic diagram of the principle process of the method of the present invention.

FIG. 2 is an XRD spectrum diagram of lithium nickel cobalt manganese oxide positive electrode material powder

FIG. 3 is an XRD spectrogram of calcine obtained by reduction roasting of nickel cobalt lithium manganate cathode material

FIG. 4 is an XRD spectrogram of transformation slag obtained after lithium is extracted from a nickel cobalt lithium manganate positive electrode material through reduction roasting and calcium chloride transformation

Detailed Description

The invention is further described below with reference to the accompanying drawings.

The method for selectively and preferentially extracting lithium from waste lithium ion batteries comprises the steps of carrying out reduction roasting on a lithium-containing positive electrode active material obtained by disassembling, crushing and screening the waste lithium ion batteries by using a carbon-containing reducing agent at 500-1100 ℃ to obtain roasted sand; and (3) mixing the calcine with water, adding a proper amount of a transformation agent for transformation, replacing and extracting lithium into a solution, and performing solid-liquid separation to obtain a lithium-containing solution and transformation slag. The transformed slag can be used for further recovery of nickel, cobalt and the like. The transformation agent is one or more of calcium chloride, lime milk, magnesium chloride, magnesium sulfate, manganese chloride, manganese sulfate, ferrous chloride, ferrous sulfate, ferric chloride and ferric sulfate. The carbonaceous reducing agent is one or more of coal powder, natural gas, carbon monoxide, coke powder, carbon powder, graphite and biomass.

In particular, the method of the present invention does not require the addition of acid for the transformation extraction of lithium, and the pH of the solution should be controlled to 5 or more even if the acid is added in some embodiments.

In some embodiments, the transformation extracting lithium is performed in a stirred mill or a dissolution mill.

In some embodiments, further comprising the steps of removing impurities and precipitating lithium, namely: adding a proper amount of lithium salt into the lithium-containing solution obtained by transformation and lithium extraction, stirring and reacting for a period of time, and then filtering to obtain a pure lithium solution; and adding a proper amount of carbonate solution or phosphate solution into the obtained pure lithium solution, stirring, and filtering to obtain a lithium carbonate or lithium phosphate product.

The process of the present invention is further illustrated by the following non-limiting examples to facilitate the understanding of the contents of the invention and its advantages, but not to limit the scope of the invention, which is defined by the claims.

Example 1

Performing reduction roasting on a nickel-cobalt manganese lithium anode material obtained by disassembling, crushing and screening a waste lithium ion battery at 500-1000 ℃ by using carbon monoxide to obtain roasted product; adding the calcine into a dissolving mill, mixing the calcine with water to obtain slurry, adding a proper amount of calcium chloride as a transformation agent, and transforming lithium carbonate in the calcine into calcium carbonate, wherein lithium is extracted into a solution. Adding calcium chloride according to the mole number of lithium in the calcine being 0.8 time, adding water according to the mass of the calcine being 1-4 times, carrying out solid-liquid separation on the slurry at the temperature of 20-100 ℃ to obtain a lithium-containing solution and transformation slag. Fig. 2, fig. 3 and fig. 4 are XRD spectrograms of the positive electrode material, the calcine and the transformation slag, respectively, and comparing the XRD spectrograms, it can be seen that nickel and cobalt are reduced into metallic nickel and metallic cobalt, manganese is reduced into MnO, and lithium is converted into lithium carbonate during reduction roasting. After the lithium is extracted by calcium chloride transformation, nickel, cobalt and manganese still remain in the transformation slag in the forms of metallic nickel, metallic cobalt and MnO respectively, and the lithium carbonate phase disappears and the calcium carbonate phase is newly added.

Example 2

Carrying out reduction roasting on a lithium cobaltate positive electrode material obtained by disassembling, crushing and screening a waste lithium ion battery at 850 ℃ by using coke powder to obtain roasted sand; adding the calcine into a stirring mill, adding water and a proper amount of lime milk, carrying out transformation and extraction on lithium, adding the calcium chloride according to the molar number of the lithium in the calcine being 0.6 time, adding the water according to the mass being 2 times of the calcine, carrying out solid-liquid separation on slurry at the temperature of 25 ℃, and obtaining a lithium-containing solution and transformation slag.

Example 3

Reducing and roasting a nickel cobalt lithium manganate positive material obtained by disassembling, crushing and screening a waste lithium ion battery at 800 ℃ by using pulverized coal to obtain roasted sand; adding the calcine into a dissolution mill, adding a proper amount of water and lime for milling and transformation, wherein the addition of the lime is 0.6 time of the molar number of lithium in the calcine, the addition of the water is 2 times of the mass of the calcine, the temperature for extracting lithium by transformation is 25 ℃, and performing solid-liquid separation on the transformed slurry to obtain a lithium-containing solution and transformation slag. Adding a proper amount of lithium phosphate into the obtained lithium-containing solution, stirring and reacting for a period of time, and filtering to obtain a pure lithium solution. And then adding a proper amount of sodium carbonate solution into the pure lithium solution, stirring and filtering to obtain a lithium carbonate product.

Example 4

The transformation slag obtained in the example 3 is slurried by an ammonia solution, air is introduced for oxidation leaching, and leaching solution containing nickel and cobalt is obtained by filtering.

Claims

1. The method for extracting lithium and nickel and cobalt from the waste lithium ion battery step by step is characterized by comprising the following steps of:

(1) reduction roasting: reducing and roasting lithium-containing materials of waste lithium ion batteries to obtain roasted sand;

(2) transformation and lithium extraction: mixing the calcine obtained in the step (1) with water to obtain slurry, adding a proper amount of a transformation agent to perform transformation extraction of lithium, and performing solid-liquid separation to obtain a lithium-containing solution and transformation slag; the transformation agent is one or more of calcium chloride, lime milk, magnesium chloride, magnesium sulfate, manganese chloride, manganese sulfate, ferrous chloride, ferrous sulfate, ferric chloride and ferric sulfate; the lithium-containing solution is used for recovering lithium, and the transformation slag is used for recovering other metal elements.

2. The method according to claim 1, wherein the lithium-containing material in the step (1) is obtained by disassembling, crushing and screening waste lithium ion batteries.

3. The method according to claim 1 or 2, wherein the lithium-containing material of step (1) is a lithium ion battery positive active material.

4. The method of claim 3, wherein the lithium ion battery positive active material is one or more of lithium cobaltate, lithium nickelate, lithium manganate, lithium nickel cobalt aluminate, and lithium vanadate.

5. The method according to claim 1, wherein the reductive roasting in the step (1) is carried out by adopting a carbon-containing reducing agent, and the carbon-containing reducing agent is one or more of coal powder, natural gas, carbon monoxide, coke powder, carbon powder, graphite and biomass.

6. The method of claim 5, wherein the carbonaceous reductant is one or more of natural gas, carbon monoxide, coke powder, carbon powder.

7. The method according to claim 1, wherein the roasting temperature of the reduction roasting in the step (1) is 500 to 1100 ℃.

8. The method as claimed in claim 7, wherein the roasting temperature of the reduction roasting in the step (1) is 550 to 850 ℃.

9. The method according to claim 1, wherein the transformation agent in the step (2) is one or two of calcium chloride and lime milk.

10. The method according to claim 1, wherein no acid is added during the transformation and lithium extraction in the step (2), and the pH value of the solution is controlled to be more than or equal to 5.

11. The method as claimed in claim 1, wherein a small amount of acid is added during the transformation and lithium extraction in step (2), and the pH value of the solution is controlled to be more than or equal to 5.

12. The method of claim 1, wherein the transformation and lithium extraction in step (2) are performed in a stirring mill or a dissolution mill.

13. The method of claim 1, further comprising steps (3), (4), (5):

(3) removing impurities: adding a proper amount of lithium salt into the lithium-containing solution obtained in the step (2), stirring and reacting for a period of time, and then filtering to obtain a pure lithium solution; the lithium salt is one or a mixture of more of the calcine, lithium phosphate and lithium carbonate in the step (1);