Separation and recovery method and application of waste high-nickel ternary battery

Abstract

The invention provides a separation and recovery method and application of a waste high-nickel ternary battery, and relates to the technical field of lithium ion batteries. Specifically, waste high-nickel ternary battery powder is subjected to a reduction acid leaching reaction in sequence, and a carbonaceous solid phase and a first liquid phase are obtained; the first liquid phase is extracted through a copper extraction agent, and a copper-rich organic phase and a raffinate water phase are obtained; sequentially carrying out alkali precipitation reaction on the raffinate water phase to obtain a hydroxide solid phase and a second liquid phase; wherein the second liquid phase is subjected to an aluminum removal reaction, then carbonate is added, solid-liquid separation is performed to obtain lithium carbonate, the hydroxide solid phase is sequentially subjected to reduction ammonia leaching to obtain a third liquid phase, and extraction separation and reverse extraction are further performed to obtain a nickel sulfate solution. According to the method, lithium carbonate is prepared by adopting front-end lithium extraction, nickel sulfate is prepared by carrying out ammonia leaching extraction on the nickel-cobalt-manganese hydroxide after lithium extraction, the lithium-nickel product with high recovery rate and high purity can be obtained while the method with high efficiency and short process is obtained, and the method has a good application prospect.

Description

Technical Field

[0001] The present invention relates to the technical field of lithium-ion batteries, and in particular to a separation and recovery method for waste high-nickel ternary batteries and applications thereof. Background Art

[0002] Against the backdrop of growing energy demand and increasingly stringent environmental protection requirements, high-nickel lithium batteries are increasingly used and in demand due to their high energy density, high power performance, and long cycle life. According to data from the Gaogong Industry Research Institute, high-nickel ternary cathodes accounted for more than 50% of my country's ternary cathode material market in the first half of 2023. However, the supply of key materials such as nickel is tight and prices fluctuate greatly, while the disposal or landfill of used batteries poses serious environmental problems. Traditional battery recycling methods are inefficient and costly when processing high-nickel batteries, and it is difficult to achieve efficient separation and recovery of valuable metals. Therefore, advanced, efficient, and environmentally friendly high-nickel battery recycling technology has become a top priority to improve resource utilization, reduce costs, and promote the sustainable development of the battery industry.

[0003] There are a lot of studies on the recovery of valuable metals in waste ternary lithium batteries in the current technology. For example, in the patent with publication number CN116121544A, multiple extractants are used for multi-stage graded extraction to recover metals. First, an extractant is used to separate the organic phase containing cobalt and manganese metal elements and the aqueous phase containing nickel and lithium metal elements; then the organic phase containing cobalt and manganese metal elements is stripped by sulfuric acid solution, so that the cobalt and manganese metal elements are transferred to the aqueous phase again, and potassium permanganate is added to the aqueous phase containing cobalt and manganese metal elements for precipitation, and the precipitation material and cobalt sulfate solution are obtained and separated; another extractant is added to the aqueous phase containing nickel and lithium metal elements to separate nickel and lithium, so that the nickel metal element is in the organic phase and the lithium metal element is in the aqueous phase, and separated, and finally sodium carbonate is added to the aqueous phase containing lithium metal elements to precipitate lithium, and lithium carbonate is obtained by drying and separation. This method solves the problems of low recovery efficiency, high cost and low purity of recovered metals of traditional metallurgical processes for cobalt, nickel, manganese and lithium, but the overall process has a large amount of wastewater and is difficult to put into production application.

[0004] Another example is the patent with publication number CN118136999A, which mixes waste high-nickel ternary polycrystalline positive electrode materials with lithium-containing molten salts, fluxes and transition metals, and after mixing evenly, performs two-stage heat treatment at low temperature and high temperature, and then cools with the furnace to obtain an intermediate product; the intermediate product is washed and filtered, and then dried and annealed to obtain a regenerated high-nickel ternary single crystal positive electrode material. This method replenishes the lost metal elements, repairs the highly degraded crystal structure, and recovers the high-nickel ternary polycrystalline positive electrode material into a high-nickel ternary single crystal positive electrode material without introducing special-shaped crystal seeds. However, although the repair of the degraded crystal structure has been achieved, its electrochemical performance is difficult to restore to the level of a new ternary positive electrode material.

[0005] In view of this, the present invention is proposed. Summary of the invention

[0006] The first purpose of the present invention is to provide a method for separating and recovering discarded high-nickel ternary batteries, which is used to solve the defects of the existing wet process for recovering waste lithium batteries, such as long and complicated process, and the defect of insufficient purity of the recovered lithium and nickel products.

[0007] A second object of the present invention is to provide a method for treating discarded lithium-ion batteries.

[0008] In order to achieve the above-mentioned purpose of the present invention, the following technical solutions are particularly adopted:

[0009] A method for separating and recycling discarded high-nickel ternary batteries comprises the following steps:

[0010] (1) subjecting the waste high-nickel ternary battery powder to reduction acid leaching reaction and solid-liquid separation in sequence to obtain a carbonaceous solid phase and a first liquid phase;

[0011] (2) extracting the first liquid phase with a copper extractant to obtain a copper-rich organic phase and a raffinate aqueous phase; stripping the copper-rich organic phase to obtain copper;

[0012] (3) subjecting the raffinate water phase to an alkali precipitation reaction and solid-liquid separation in sequence to obtain a hydroxide solid phase and a second liquid phase;

[0013] (4) subjecting the second liquid phase to an aluminum removal reaction, and then adding carbonate and performing solid-liquid separation to obtain lithium carbonate;

[0014] (5) subjecting the hydroxide solid phase to reduction ammonia leaching and solid-liquid separation in sequence to obtain manganese slag and a third liquid phase;

[0015] (6) extracting and separating the third liquid phase to obtain a nickel organic phase and a cobalt solution; and stripping the nickel organic phase to obtain a nickel sulfate solution.

[0016] A method for treating waste lithium-ion batteries, including the separation and recovery method of waste high-nickel ternary batteries.

[0017] Compared with the prior art, the present invention has the following beneficial effects:

[0018] The method of recovering nickel and lithium from waste high-nickel ternary lithium batteries of the present invention prepares battery-grade lithium carbonate and nickel sulfate solution, and the preparation process is efficient and scalable. In the present invention, lithium carbonate is prepared by front-end lithium extraction, and nickel-cobalt-manganese hydroxide after lithium extraction is subjected to ammonia leaching extraction to prepare nickel sulfate; on the one hand, front-end lithium extraction effectively eliminates the complex process of recovering lithium metal after MVR concentration in the traditional process, while avoiding the negative impact of the recovery process reagents on lithium extraction; on the other hand, a short process at room temperature is adopted in the subsequent nickel sulfate recovery process, avoiding the complex and lengthy process of multiple extractants in series, greatly reducing the demand for energy consumption and environmental pollution in the waste high-nickel ternary lithium battery recovery process. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In order to more clearly illustrate the specific implementation methods of the present invention or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0020] Figure 1 A flow chart of the method of embodiment 1 of the present invention is provided. DETAILED DESCRIPTION

[0021] The technical scheme of the present invention will be clearly and completely described below in conjunction with the accompanying drawings and specific embodiments, but those skilled in the art will appreciate that the following described embodiments are part of embodiments of the present invention, rather than all embodiments, and are only used to illustrate the present invention, and should not be considered as limiting the scope of the present invention. Based on the embodiments in the present invention, all other embodiments obtained by those of ordinary skill in the art without making creative work are within the scope of protection of the present invention. Those who do not specify specific conditions in the embodiments are carried out according to conventional conditions or conditions recommended by the manufacturer. Those who do not specify the manufacturer of the reagents or instruments used are all conventional products that can be purchased commercially. In addition, the terms "one", "two", "1", "2" are only used for descriptive purposes and cannot be interpreted as indicating or implying relative importance.

[0022] The first object of the present invention is to provide a method for separating and recycling discarded high-nickel ternary batteries.

[0023] The existing wet process for recycling waste lithium batteries usually includes the following processes: reduction leaching, copper extraction to remove copper, neutralization to remove iron and aluminum, manganese extraction to remove impurities, cobalt extraction, nickel extraction, and nickel-magnesium separation, thereby realizing the recovery of nickel, cobalt, and manganese metals. However, this type of process is complex and lengthy, requiring multiple extraction and back-extraction operations to separate and purify different metal elements, and the yield of lithium ions is low. Based on the existing selection of extractants, a small amount of lithium ions will be extracted or entrained in each extraction stage, resulting in the lithium content in the final wastewater that needs to be recovered. In summary, with regard to the recovery of nickel, cobalt, and lithium metals in waste high-nickel ternary lithium batteries, the existing wet process for recycling waste lithium batteries cannot simply and effectively separate the nickel, cobalt, manganese, and lithium in a short process to obtain pure nickel sulfate and battery-grade lithium carbonate products.

[0024] The present invention avoids the loss of nickel, cobalt and lithium metals in the traditional neutralization and iron and aluminum removal process by front-end lithium extraction and ammonia leaching, and uses an extractant in an ammonia system to extract nickel alone. Specifically, it includes the following steps (1) to (6), and the functional effects and extended implementation methods of each step will be specifically explained below.

[0025] (1) Waste high-nickel ternary battery powder is subjected to reduction acid leaching reaction and solid-liquid separation in sequence to obtain a carbonaceous solid phase and a first liquid phase.

[0026] In step (1) of the present invention, the recovered high-nickel ternary battery powder is reductively dissolved by an acid leaching method, the insoluble carbonaceous solid phase is separated, and a liquid phase enriched with various metal ions is obtained for subsequent metal separation.

[0027] As a preferred embodiment, the waste high-nickel ternary battery powder is obtained by disassembling, separating and crushing the waste high-nickel ternary batteries.

[0028] Specifically, the high-nickel ternary battery refers to a lithium-ion battery with a nickel content of more than 60wt.% in the positive electrode material. The powder refers to a powder obtained by disassembling the positive and negative electrodes of the high-nickel ternary battery, crushing them to a particle size of less than 125mm (screened with 120 mesh), and then carbonizing and pyrolyzing them at 400℃ to 600℃ for 1h; the above treatment can crack organic matter such as electrolyte, diaphragm, adhesive into short-chain alkane-type small molecule organic matter.

[0029] As an optional implementation, the discarded high-nickel ternary batteries are crushed, and the crushing treatment includes one of mechanical crushing, low-temperature crushing or ultrasonic crushing. Those skilled in the art can make any selection or combination according to the scale of waste battery processing and the degree of crushing.

[0030] As a preferred embodiment, the acid reagent of the reduction acid leaching reaction includes concentrated sulfuric acid, and the reducing reagent includes one or more of hydrogen peroxide, sodium pyrosulfite or sulfur dioxide; it can be understood that sulfuric acid-based reagents are used in the acid reagents involved in the present invention. Although from a functional point of view, hydrochloric acid, nitric acid, etc. can also achieve corresponding functions, from the perspective of avoiding the introduction of redundant anion groups and the purity of the separated product, the present invention still prefers sulfuric acid.

[0031] As a more preferred embodiment, in the reaction liquid system of the reduction acid leaching reaction, the battery powder of the processing raw material and the reagents used should have one or more of the following dosage relationships:

[0032] (a) the nickel content of the waste high-nickel ternary battery powder is greater than 30wt.%;

[0033] (b) the solid-liquid ratio of the reaction liquid system is 1:(4-6.5) (g / mL);

[0034] (c) adding the acid reagent until the pH of the reaction solution is 0.5 to 2.0;

[0035] (d) Calculated by the amount of substance, the amount of the reducing agent used is the sum of 0.5 to 1 times the molar amount of trivalent cobalt in the waste high-nickel ternary battery powder and 1 times the molar amount of trivalent manganese.

[0036] As a preferred embodiment, the temperature of the reduction acid leaching reaction is 50°C to 80°C, and the duration is 2h to 8h; in some optional embodiments, the temperature of the reduction acid leaching reaction includes but is not limited to any one of 50, 55, 60, 65, 70, 75, 80 (°C) or a numerical range composed of any two of them, and the duration includes but is not limited to any one of 2, 3, 4, 5, 6, 7, 8 (h) or a numerical range composed of any two of them.

[0037] As a preferred embodiment, any one of the solid-liquid separations involved in the present invention includes but is not limited to decantation, filtration, centrifugation, filter or membrane separation, etc.; in a more preferred embodiment, the solid-liquid separation in this step is carried out by suction filtration in a low-yield production mode or a laboratory scenario, and in a large-scale batch production mode, the solid-liquid separation can be carried out by a filter.

[0038] (2) extracting the first liquid phase with a copper extractant to obtain a copper-rich organic phase and a raffinate aqueous phase; and stripping the copper-rich organic phase to obtain copper.

[0039] In step (2) of the present invention, copper is extracted and stripped. On the one hand, copper is separated from a mixed solution of other metal ions by extraction, and on the other hand, a high-purity copper sulfate solution product is obtained with a high separation efficiency.

[0040] As a preferred embodiment, the copper extractant includes a solution of Mextral 984H; in some more preferred embodiments, the solvent includes sulfonated kerosene with a volume concentration of 8% to 15%, more preferably 10%.

[0041] As a preferred embodiment, the pH of the first liquid phase is 1.0-2.0; in some optional embodiments, when the pH of the first liquid phase is not in the above range, the pH is adjusted before the extraction of the copper extractant is carried out.

[0042] As a preferred embodiment, the volume ratio of the first liquid phase to the copper extractant is (15-25):1, more preferably 20:1; that is, for the extractant Mextral984H, the maximum copper loading capacity of the extractant at a volume concentration of 10% is 5.0-5.4 g / L.

[0043] As a preferred embodiment, the volume ratio of the copper-rich organic phase to the raffinate aqueous phase is (0.5-2):1, more preferably 1:2; that is, in the organic phase (O) and the aqueous phase (A) after extraction with the copper extractant, O / A is the above-mentioned limited value.

[0044] As a preferred embodiment, the reagent used in the stripping includes a sulfuric acid solution with a concentration of 2 mol / L to 6 mol / L.

[0045] As a more preferred embodiment, the volume ratio of the copper-rich organic phase to the stripping agent is (8-15):1, more preferably 10:1.

[0046] (3) subjecting the raffinate water phase to alkaline precipitation reaction and solid-liquid separation in sequence to obtain a hydroxide solid phase and a second liquid phase.

[0047] In step (3) of the present invention, the solution containing nickel, cobalt, manganese, lithium and other metals after copper removal (i.e., the raffinate aqueous phase) is subjected to alkaline precipitation to remove metals such as nickel, cobalt, manganese and other metals other than lithium and aluminum and form corresponding hydroxide precipitates, thereby achieving preliminary separation of lithium.

[0048] As a preferred embodiment, the alkaline reagent for the alkaline precipitation reaction includes one or more of lithium hydroxide, potassium hydroxide or sodium hydroxide; in some more preferred embodiments, the alkaline reagent is introduced in the form of an aqueous solution to achieve pH adjustment more quickly and accurately, and the concentration of the alkaline reagent is 3 mol / L to 10 mol / L, and more preferably 3 mol / L.

[0049] As a preferred embodiment, a reaction solution with a pH of 10 to 11 is obtained through the alkaline precipitation reaction; or it can be understood that the pH of the raffinate water phase after the alkaline precipitation reaction is 10 to 11.

[0050] As a preferred embodiment, the temperature of the alkali precipitation reaction is not limited and can usually be carried out at room temperature; the duration of the alkali precipitation reaction is 40 minutes to 80 minutes; in some optional embodiments, the alkali precipitation reaction can be assisted by stirring, shaking, etc.

[0051] As a preferred embodiment, step (3) further includes: washing the hydroxide solid phase with water, including but not limited to rinsing, stirring, soaking, etc., to avoid lithium being entrained into the nickel-cobalt-manganese hydroxide.

[0052] (4) subjecting the second liquid phase to aluminum removal reaction, and then adding carbonate and performing solid-liquid separation to obtain lithium carbonate.

[0053] In step (4) of the present invention, the pH is adjusted to carry out neutralization treatment to control the precipitation of aluminum into aluminum hydroxide, thereby separating it from the lithium-containing solution, and further precipitating to obtain a high-purity lithium carbonate product.

[0054] It is worth noting that the addition method of the carbonate in this step can be either positive addition or negative addition; the positive addition method is to use the solution of the second liquid phase after the aluminum removal reaction as the base, and add the carbonate (or the solution of the carbonate); the negative addition method is to use the solution of the carbonate as the base, and add the solution of the second liquid phase after the aluminum removal reaction.

[0055] As a preferred embodiment, the aluminum removal reaction includes: adjusting the pH of the second liquid phase to 6.0-7.0, continuing the reaction and then separating the solid and liquid; in some more preferred embodiments, the temperature of the aluminum removal reaction is 80°C-95°C, and the duration of the aluminum removal reaction is >2h.

[0056] As a more preferred embodiment, the reagents for the aluminum removal reaction include sulfuric acid, sodium hydroxide or potassium hydroxide; those skilled in the art can adaptively adjust the selection of acid-base reagents according to the acid-base condition of the second liquid phase; but it can be understood that the present invention can also select reagents such as potassium hydroxide to increase the lithium ion concentration, which can be comprehensively considered through the cost of waste resource utilization.

[0057] As a preferred embodiment, step (4) further comprises: after the aluminum removal reaction, evaporating and concentrating the lithium-containing liquid phase, adjusting the pH of the lithium-containing liquid phase to 10.5-11.5, and then adding the carbonate, thereby achieving lithium enrichment and accelerating the lithium precipitation collection efficiency.

[0058] As a more preferred embodiment, the evaporation concentration is carried out in an environment higher than 100° C., and the duration of the evaporation concentration is based on the lithium ion concentration in the lithium-containing liquid phase being greater than 15 g / L.

[0059] As a preferred embodiment, after adding the carbonate, the reaction is continued at 80° C. to 85° C. for 1.5 h to 3 h, and then solid-liquid separation is performed.

[0060] As a preferred embodiment, the carbonate includes any soluble carbonate, such as one or more of sodium carbonate, potassium carbonate or ammonium carbonate.

[0061] As a preferred embodiment, the amount of carbonate added is 1.1 to 1.3 times the molar amount of lithium ions in the second liquid phase, that is, the amount of carbonate is controlled to be slightly higher than the amount of lithium ions to ensure complete precipitation of lithium ions.

[0062] (5) The hydroxide solid phase is sequentially subjected to reduction ammonia leaching and solid-liquid separation to obtain manganese slag and a third liquid phase.

[0063] In step (5) of the present invention, a nickel-cobalt complex is obtained by treating a hydroxide solid phase containing nickel, cobalt and manganese with ammonia complex. At the same time, the introduced reducing agent reduces the high-valent metal ions to +2 valence, thereby forming an alkaline precipitate of manganese ions in the reaction system, and nickel and cobalt exist in the third liquid phase in the form of an ammonia complex.

[0064] As a preferred embodiment, the reductive ammonia leaching comprises the following steps: adding the hydroxide solid phase into an ammonia solution, and then adding a second reducing agent to react.

[0065] As a more preferred embodiment, the ammonia solution includes ammonia monohydrate and ammonium bicarbonate, and the molar ratio of the two is (2-4):1, and 3:1 is further preferred; in terms of ammonium ion concentration, the concentration of the ammonia solution is 4 mol / L-10 mol / L, and 8 mol / L is further preferred.

[0066] As a more preferred embodiment, the second reducing agent includes at least one of hydrazine hydrate or sodium pyrosulfite; hydrazine hydrate is further preferably used.

[0067] As a more preferred embodiment, the liquid-to-solid ratio of the ammonia solution to the hydroxide solid phase is (10-15):1, and the dimension is: mL / g.

[0068] As a more preferred embodiment, the amount of the second reducing agent added is 0.5 times the molar amount of cobalt in the hydroxide solid phase, calculated on the amount of substance.

[0069] As a preferred embodiment, the reaction temperature of the reduction ammonia leaching is not limited and can usually be carried out at room temperature; the reaction time of the reduction ammonia leaching is 4h to 12h.

[0070] (6) extracting and separating the third liquid phase to obtain a nickel organic phase and a cobalt solution; and stripping the nickel organic phase to obtain a nickel sulfate solution.

[0071] In step (6) of the present invention, nickel and cobalt are extracted and separated, and a nickel salt product is further obtained by back extraction.

[0072] As a preferred embodiment, the extractant for the extraction comprises a solution of the extractant LIX84; the solvent comprises sulfonated kerosene with a volume concentration of 10% to 20%.

[0073] As a preferred embodiment, the volume ratio of the nickel organic phase to the cobalt solution is (4.5-8.5):1; that is, in the organic phase (O) and the aqueous phase (A) after extraction by the extractant, O / A is (4.5-8.5):1.

[0074] As a preferred embodiment, the extraction separation time of this step is 4 minutes to 8 minutes; in some more preferred embodiments, the extraction adopts three-stage countercurrent extraction, and the extraction temperature is room temperature.

[0075] As a preferred embodiment, the stripping in this step comprises: firstly countercurrent washing with pure water, standing for stratification, and then stripping the organic phase with stripping acid; in some more preferred embodiments, the stripping acid comprises 1.0 mol / L to 3.0 mol / L sulfuric acid.

[0076] As a preferred embodiment, the countercurrent washing adopts 2 to 5 stages of countercurrent washing, and the stripping adopts 3 to 6 stages of countercurrent stripping; in some more preferred embodiments, the stripping time is 10 min to 20 min, and the stripping temperature is room temperature.

[0077] As a more preferred embodiment, the volume ratio of the pure water to the nickel organic phase is 1:(1.5-2.5), and more preferably 1:2.

[0078] As a more preferred embodiment, the amount of the stripping acid is calculated based on the pH of the stripping solution, and the pH of the stripping solution is 1.5 to 2.5.

[0079] As a preferred embodiment, step (6) further comprises: evaporating the cobalt solution to obtain ammonia-containing vapor and cobalt slag; the ammonia-containing vapor is condensed to obtain ammonia water, which can be used for the pre-step or enrichment recovery.

[0080] A second aspect of the present invention is to provide a method for treating waste lithium-ion batteries.

[0081] The treatment method includes the separation and recovery method of waste high-nickel ternary batteries as described in the first aspect. It can be understood that in the treatment method described in this aspect, the waste batteries targeted are not limited to high-nickel ternary batteries, but can be any lithium battery containing one or more of carbon, manganese, nickel, aluminum, and cobalt; the treatment method can be based on the separation and recovery method, and any other conventional or unconventional operation steps can be pre-placed, superimposed, interspersed, or post-placed. When the treatment method includes the separation and recovery method, it can be regarded as an embodiment of the present invention.

[0082] Example 1

[0083] like Figure 1 The method flow chart of this embodiment is shown in FIG.

[0084] (1) Disassemble the waste high-nickel ternary lithium battery and obtain its electrode powder. After testing, the mass fraction of each element component is: 30.15% Ni, 3.58% Co, 3.70% Mn, 5.75% Li, 0.94% Cu, 0.62% Fe, 1.30% Al, 0.22% Ca, and 0.04% Mg.

[0085] The high-nickel waste high-nickel ternary lithium battery powder and water were mixed and slurried at a solid-liquid ratio of 1:4 (g / mL), sulfuric acid was added to control the pH value of the reaction end point to 1.25 (the amount of sulfuric acid used was 1.05 times the sum of the molar amounts of each component of the waste high-nickel ternary lithium battery powder), the reaction temperature was controlled to 50°C, and hydrogen peroxide was added during the reaction for reduction leaching (the amount of hydrogen peroxide used was 1 times the sum of the molar amount of trivalent cobalt and 1 times the molar amount of trivalent manganese in the battery black powder), and the reaction time was 4h. After the reaction was completed, solid-liquid separation was performed to obtain reduction leaching solution and carbon slag.

[0086] After testing, the contents of the main elements in the reduction leaching solution are: Ni: 69.31 g / L, Co: 8.22 g / L, Mn: 8.51 g / L, Li: 13.12 g / L. The carbon slag is mixed with water to form a slurry for washing, and then packaged to obtain a by-product whose main component is carbon powder.

[0087] (2) extracting the reduction leaching solution from step (1) with a copper extractant (Mextral 984H, with a volume concentration of 10%, and a solvent of sulfonated kerosene) at a ratio of O / A=1:2. After the extraction is completed, the phases are allowed to stand for separation, and the organic phase is a copper-rich organic phase and an aqueous phase is a copper raffinate. Slowly add a 3 mol / L sodium hydroxide solution to the copper raffinate, adjust the pH to 11, react for 1 hour, and then perform solid-liquid separation to obtain a lithium-containing solution and nickel-cobalt-manganese hydroxide, and wash the nickel-cobalt-manganese hydroxide with pure water.

[0088] After the lithium-containing liquid is heated to 90° C., the pH is adjusted to 7.0 and reacted for 2 hours, and the lithium hydroxide liquid after aluminum removal is obtained by filtration; after the lithium hydroxide liquid is evaporated and concentrated until the lithium content reaches more than 15 g / L, the pH value of the solution is first adjusted to 11, and then a saturated sodium carbonate solution with a theoretical amount of 1.3 times is added, and the reaction is carried out at 85° C. for 4 hours. After the reaction is completed, solid-liquid separation is performed to obtain the lithium carbonate product of this embodiment.

[0089] (3) The nickel-cobalt-manganese hydroxide obtained in step (2) is added to an ammonia water mixed solution (1L 25% ammonia water, 100g ammonium bicarbonate) at a liquid-solid ratio of 15:1, and the reducing agent hydrazine hydrate is slowly added dropwise, wherein the amount of hydrazine hydrate used is 0.5 times the molar amount of cobalt; after reacting at room temperature for 6 hours, the solid and liquid are separated to obtain a nickel-cobalt complex ammonia solution, wherein Ni: 39.72g / L, Co: 5.18g / L.

[0090] (4) Add LIX84 extractant (volume concentration of 10%, solvent is sulfonated kerosene) to the nickel-cobalt complex ammonia solution obtained in step (3) at a phase ratio of O / A=8.5:1, perform 3-stage countercurrent extraction at room temperature for 5 minutes, and then separate the phases to obtain an organic phase and a raffinate (aqueous phase). Boil and evaporate the raffinate, collect the steam and condense it to obtain ammonia water, and the powder remaining after evaporation is cobalt slag.

[0091] The organic phase was washed with pure water at a ratio of O / A=2:1 for two-stage countercurrent washing. After washing, 1.5 mol / L sulfuric acid was further added to the organic phase for three-stage countercurrent stripping for 15 minutes. The equilibrium pH of the stripping solution was 1.65. The obtained stripping solution was a nickel sulfate solution.

[0092] Example 2

[0093] (1) Disassemble the waste high-nickel ternary lithium battery and obtain its electrode powder. After testing, the mass fraction of each element component is: 40.47% Ni, 5.10% Co, 5.34% Mn, 6.17% Li, 0.95% Cu, 0.52% Fe, 1.13% Al, 0.32% Ca, and 0.04% Mg.

[0094] The high-nickel waste high-nickel ternary lithium battery powder and water were mixed and slurried at a solid-liquid ratio of 1:5.3 (g / mL), sulfuric acid was added to control the pH value of the reaction end point to 1.5 (the amount of sulfuric acid used was 1.05 times the sum of the molar amounts of each component of the waste high-nickel ternary lithium battery powder), the reaction temperature was controlled to 80°C, and hydrogen peroxide was added during the reaction for reduction leaching (the amount of hydrogen peroxide used was 1 times the sum of the molar amount of trivalent cobalt and 1 times the molar amount of trivalent manganese in the battery black powder), and the reaction time was 4h. After the reaction was completed, solid-liquid separation was performed to obtain reduction leaching solution and carbon slag.

[0095] After testing, the contents of the main elements in the reduction leaching solution are: Ni: 70.15 g / L, Co: 8.84 g / L, Mn: 9.26 g / L, Li: 10.70 g / L. The carbon slag is mixed with water to form a slurry for washing, and then packaged to obtain a by-product whose main component is carbon powder.

[0096] (2) extracting the reduction leaching solution from step (1) with a copper extractant (Mextral 984H, with a volume concentration of 10%, and a solvent of sulfonated kerosene) at a ratio of O / A=1:2. After the extraction is completed, the phases are allowed to stand for separation, and the organic phase is a copper-rich organic phase and an aqueous phase is a copper raffinate. Slowly add a 3 mol / L sodium hydroxide solution to the copper raffinate, adjust the pH to 11, react for 1 hour, and then perform solid-liquid separation to obtain a lithium-containing solution and nickel-cobalt-manganese hydroxide, and wash the nickel-cobalt-manganese hydroxide with pure water.

[0097] After the lithium-containing liquid is heated to 90° C., the pH is adjusted to 7.0 and reacted for 2 hours, and the lithium hydroxide liquid after aluminum removal is obtained by filtration; after the lithium hydroxide liquid is evaporated and concentrated until the lithium content reaches more than 15 g / L, the pH value of the solution is first adjusted to 11, and then a saturated sodium carbonate solution with a theoretical amount of 1.3 times is added, and the reaction is carried out at 85° C. for 4 hours. After the reaction is completed, solid-liquid separation is performed to obtain the lithium carbonate product of this embodiment.

[0098] (3) The nickel-cobalt-manganese hydroxide obtained in step (2) is added to an ammonia water mixed solution (1L 25% ammonia water, 100g ammonium bicarbonate) at a liquid-solid ratio of 15:1, and the reducing agent hydrazine hydrate is slowly added dropwise, wherein the amount of hydrazine hydrate used is 0.2 times the molar amount of cobalt; after reacting at room temperature for 8 hours, the solid and liquid are separated to obtain a nickel-cobalt complex ammonia solution, wherein Ni: 39.29g / L, Co: 5.23g / L.

[0099] (4) Add LIX84 extractant (volume concentration of 10%, solvent is sulfonated kerosene) to the nickel-cobalt complex ammonia solution obtained in step (3) at a phase ratio of O / A=8.5:1, perform 3-stage countercurrent extraction at room temperature for 5 minutes, and then separate the phases to obtain an organic phase and a raffinate (aqueous phase). Boil and evaporate the raffinate, collect the steam and condense it to obtain ammonia water, and the powder remaining after evaporation is cobalt slag.

[0100] The organic phase was washed with pure water at a ratio of O / A=2:1 for two-stage countercurrent washing. After washing, 1.5 mol / L sulfuric acid was further added to the organic phase for three-stage countercurrent stripping for 15 minutes. The equilibrium pH of the stripping solution was 1.66. The obtained stripping solution was a nickel sulfate solution.

[0101] Example 3

[0102] (1) Disassemble the waste high-nickel ternary lithium battery and obtain its electrode powder. After testing, the mass fraction of each element component is: 48.27% Ni, 6.06% Co, 5.65% Mn, 7.15% Li, 0.74% Cu, 0.50% Fe, 1.33% Al, 0.32% Ca, and 0.04% Mg.

[0103] The high-nickel waste high-nickel ternary lithium battery powder and water were mixed and slurried at a solid-liquid ratio of 1:6.5 (g / mL), sulfuric acid was added to control the pH value of the reaction end point to 1.0 (the amount of sulfuric acid used was 1.05 times the sum of the molar amounts of each component of the waste high-nickel ternary lithium battery powder), the reaction temperature was controlled to 65°C, and hydrogen peroxide was added during the reaction for reduction leaching (the amount of hydrogen peroxide used was 0.5 times the molar amount of trivalent cobalt in the battery black powder and 1 times the molar amount of trivalent manganese), and the reaction time was 2h. After the reaction was completed, solid-liquid separation was performed to obtain reduction leaching solution and carbon slag.

[0104] After testing, the contents of the main elements in the reduction leaching solution are: Ni: 70.34 g / L, Co: 8.89 g / L, Mn: 8.35 g / L, Li: 10.51 g / L. The carbon slag is mixed with water to form a slurry for washing, and then packaged to obtain a by-product whose main component is carbon powder.

[0105] (2) extracting the reduction leaching solution from step (1) with a copper extractant (Mextral 984H, with a volume concentration of 10%, and a solvent of sulfonated kerosene) at a ratio of O / A=1:2. After the extraction is completed, the phases are allowed to stand for separation, and the organic phase is a copper-rich organic phase and an aqueous phase is a copper raffinate. Slowly add a 3 mol / L sodium hydroxide solution to the copper raffinate, adjust the pH to 11, react for 1 hour, and then perform solid-liquid separation to obtain a lithium-containing solution and nickel-cobalt-manganese hydroxide, and wash the nickel-cobalt-manganese hydroxide with pure water.

[0106] The lithium-containing liquid was heated to 90°C, adjusted to pH = 7.0 and reacted for 2 hours, and then filtered to obtain the lithium hydroxide liquid after aluminum removal; the lithium hydroxide liquid was evaporated and concentrated until the lithium content reached more than 15 g / L, and the composition of the concentrated lithium hydroxide liquid at this time was detected and recorded (in g / L), as shown in Table 1.

[0107] Table 1

[0108] Li On I will Fe Ca Mg Mn Zn Al Nor Yes F 15.66 96.51 0.0001 0.0002 0.0005 0.0002 0.0001 0.0001 0.0002 0.0001 0.0020 0.10

[0109] First, the pH value of the concentrated lithium hydroxide solution was adjusted to 10.5, and then a saturated sodium carbonate solution of 1.3 times the theoretical amount was added, and the mixture was reacted at 85° C. for 4 h. After the reaction was completed, solid-liquid separation was performed to obtain the lithium carbonate product of this embodiment.

[0110] (3) The nickel-cobalt-manganese hydroxide obtained in step (2) is added to an ammonia water mixed solution (1L 25% ammonia water, 100g ammonium bicarbonate) at a liquid-solid ratio of 15:1, and the reducing agent hydrazine hydrate is slowly added dropwise, wherein the amount of hydrazine hydrate used is 0.1 times the molar amount of cobalt; after reacting at room temperature for 8 hours, the solid and liquid are separated to obtain a nickel-cobalt complex ammonia solution, wherein Ni: 39.20g / L, Co: 5.10g / L.

[0111] (4) Add LIX84 extractant (volume concentration 10%, solvent is sulfonated kerosene) to the nickel-cobalt complex ammonia solution obtained in step (3) at a phase ratio of O / A=8.5:1, perform 3-stage countercurrent extraction at room temperature for 5 minutes, and then separate the phases to obtain an organic phase and a raffinate (aqueous phase). Boil the raffinate and evaporate it, collect the steam and condense it to obtain ammonia water, and the powder left after evaporation is cobalt slag.

[0112] The organic phase was washed with pure water at a ratio of O / A=2:1 for two-stage countercurrent washing. After washing, 1.5 mol / L sulfuric acid was further added to the organic phase for three-stage countercurrent stripping for 15 minutes. The equilibrium pH of the stripping solution was 1.65. The obtained stripping solution was a nickel sulfate solution.

[0113] Example 4

[0114] It is basically the same as Example 3, except that:

[0115] Step (4): Add LIX84 extractant (volume concentration 15%, solvent is sulfonated kerosene) to the nickel-cobalt complex ammonia solution at a ratio of O / A = 6.4:1, and finally obtain a stripping solution (nickel sulfate solution) with a pH of 1.64.

[0116] Example 5

[0117] It is basically the same as Example 3, except that:

[0118] Step (4): Add LIX84 extractant (volume concentration 20%, solvent is sulfonated kerosene) to the nickel-cobalt complex ammonia solution at a phase ratio of O / A = 4.5:1, and finally obtain a stripping solution (nickel sulfate solution) with a pH of 1.65.

[0119] Example 6

[0120] It is basically the same as Example 3, except that:

[0121] Step (4): pure water was added to the organic phase at a ratio of O / A = 2:1 for 5-stage countercurrent washing. After washing, 1.5 mol / L sulfuric acid was further added to the organic phase for 3-stage countercurrent stripping for 15 min. The equilibrium pH of the stripping solution was 1.68.

[0122] Example 7

[0123] It is basically the same as Example 3, except that:

[0124] Step (4): 1.5 mol / L sulfuric acid was further added to the organic phase for 3-stage countercurrent stripping for 15 min, and the equilibrium pH of the stripping solution was controlled to be 2.01.

[0125] Example 8

[0126] It is basically the same as Example 3, except that:

[0127] Step (4): 1.5 mol / L sulfuric acid was further added to the organic phase for 6-stage countercurrent stripping for 15 min, and the equilibrium pH of the stripping solution was 1.68.

[0128] Example 9

[0129] It is basically the same as Example 3, except that:

[0130] Step (4): pure water was added to the organic phase at a ratio of O / A = 2:1 for 5-stage countercurrent washing. After washing, 1.5 mol / L sulfuric acid was further added to the organic phase for 6-stage countercurrent stripping for 15 min. The equilibrium pH of the stripping solution was 1.66.

[0131] The lithium carbonate prepared in step (2) and the nickel sulfate solution prepared in step (4) of each embodiment were tested and their components were recorded in Table 2 and Table 3, respectively, wherein Table 2 is expressed in terms of the mass percentage of each element and Table 3 is expressed in terms of g / L.

[0132] Table 2

[0133]

[0134]

[0135] Table 3

[0136]

[0137] Based on Table 2 and Table 3 and the element contents contained in the initial electrode powder, the recovery of nickel and lithium elements in each embodiment can be obtained, and the calculated results are recorded in Table 4.

[0138] Table 4

[0139]

[0140] As can be seen from Tables 1 and 2, the lithium carbonate recovered by the method of the present invention has reached the battery-grade lithium carbonate standard. As can be seen from Table 3, in Examples 3 to 5, as the concentration of the extractant LIX84 increases, the cobalt content in the nickel sulfate solution will also increase slightly, which shows that the extractant LIX84 will extract trace cobalt ammonia complexes; in Examples 6 and 9, the increase in the number of organic washing stages can greatly reduce the content of ammonium and silicon in the nickel sulfate solution; in Example 7, the equilibrium pH of the stripping is increased, and the silicon content in the nickel sulfate solution will increase, but the content of other impurities remains basically the same; through Examples 8 and 9, simply increasing the stripping stage has no obvious effect on the nickel sulfate solution, but increasing the washing and stripping stages at the same time can not only increase the nickel stripping rate, but also reduce the content of impurities such as ammonium and silicon, thereby obtaining a purer nickel sulfate solution. Further, it can be seen from Table 4 that the nickel lithium yield has reached 95%.

[0141] In summary, the method of the present invention for recovering nickel and lithium from waste high-nickel ternary lithium batteries prepares battery-grade lithium carbonate and nickel sulfate solutions, and has good application prospects.

[0142] Although the present invention has been illustrated and described with specific embodiments, it should be appreciated that the above embodiments are only used to illustrate the technical solutions of the present invention rather than to limit it. Those skilled in the art should understand that the technical solutions described in the above embodiments may be modified, or some or all of the technical features thereof may be replaced by equivalents without departing from the spirit and scope of the present invention. However, these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present invention. Therefore, this means that all such replacements and modifications within the scope of the present invention are included in the appended claims.

Claims

1. A method for separating and recovering waste high-nickel ternary batteries, characterized in that: The steps include: (1) subjecting the waste high-nickel ternary battery powder to reduction acid leaching reaction and solid-liquid separation in sequence to obtain a carbonaceous solid phase and a first liquid phase; (2) extracting the first liquid phase with a copper extractant to obtain a copper-rich organic phase and a raffinate aqueous phase; The copper-rich organic phase is stripped to obtain copper; (3) subjecting the raffinate water phase to an alkali precipitation reaction and solid-liquid separation in sequence to obtain a hydroxide solid phase and a second liquid phase; (4) subjecting the second liquid phase to an aluminum removal reaction, and then adding carbonate and performing solid-liquid separation to obtain lithium carbonate; (5) subjecting the hydroxide solid phase to reduction ammonia leaching and solid-liquid separation in sequence to obtain manganese slag and a third liquid phase; (6) extracting and separating the third liquid phase to obtain a nickel organic phase and a cobalt solution; and stripping the nickel organic phase to obtain a nickel sulfate solution.

2. The method for separating and recovering waste high-nickel ternary batteries according to claim 1, characterized in that: In step (1), the reduction acid leaching reaction comprises: adding an acid reagent to the solution of the waste high-nickel ternary battery powder until the pH is 0.5 to 2.0, and then adding a reducing reagent and reacting.

3. The method for separating and recovering waste high-nickel ternary batteries according to claim 2, characterized in that: The acid reagent includes concentrated sulfuric acid; and / or, the reducing agent comprises one or more of hydrogen peroxide, sodium pyrosulfite or sulfur dioxide; Preferably, the reduction acid leaching reaction is carried out at a temperature of 50°C to 80°C and for a duration of 2h to 8h.

4. The method for separating and recovering waste high-nickel ternary batteries according to claim 1, characterized in that: In step (2), the copper extractant includes Mextral 984H; the stripping reagent includes a sulfuric acid solution with a concentration of 2 mol / L to 6 mol / L.

5. The method for separating and recycling waste high-nickel ternary batteries according to claim 1, characterized in that: In step (3), the alkaline reagent for the alkaline precipitation reaction includes one or more of lithium hydroxide, potassium hydroxide or sodium hydroxide; preferably, the concentration of the alkaline reagent is 3 mol / L to 10 mol / L; Preferably, the duration of the alkali precipitation reaction is 40 min to 80 min.

6. The method for separating and recycling waste high-nickel ternary batteries according to claim 1, characterized in that: In step (4), the aluminum removal reaction includes: adjusting the pH of the second liquid phase to 6.0-7.0, continuing the reaction and then performing solid-liquid separation; Preferably, the temperature of the aluminum removal reaction is 80° C. to 95° C., and the duration of the aluminum removal reaction is >2 h.

7. The method for separating and recycling waste high-nickel ternary batteries according to claim 1, characterized in that: Step (4) also includes: after the aluminum removal reaction, evaporating and concentrating the lithium-containing liquid phase, adjusting the pH to 10.5-11.5, and then adding the carbonate; And / or, after adding the carbonate, the reaction is continued at 80° C. to 85° C. for 1.5 h to 3 h, and then solid-liquid separation is performed.

8. The method for separating and recycling waste high-nickel ternary batteries according to claim 1, characterized in that: In step (5), the reduction ammonia leaching comprises the following steps: adding the hydroxide solid phase into an ammonia solution, and then adding a second reducing agent to react; Preferably, the ammonia solution comprises ammonia monohydrate and ammonium bicarbonate, and the molar ratio of the two is (2-4):1; the concentration of the ammonia solution is 4 mol / L-10 mol / L in terms of ammonium ion concentration; Preferably, the second reducing agent comprises at least one of hydrazine hydrate or sodium metabisulfite.

9. The method for separating and recycling waste high-nickel ternary batteries according to claim 1, characterized in that: In step (6), the extractant for the extraction includes extractant LIX84; And / or, in step (6), the stripping comprises: countercurrent washing with pure water, standing for stratification, and then stripping the organic phase with a stripping acid, wherein the stripping acid comprises 1.0 mol / L to 3.0 mol / L sulfuric acid.

10. A method for treating waste lithium-ion batteries, characterized in that: The treatment method includes the separation and recovery method of waste high-nickel ternary batteries as described in any one of claims 1 to 9.

Images