阅读说明：本技术 一种废旧动力锂电池中有价金属选择性提取及三元正极材料再制备的工艺 (Process for selectively extracting valuable metals from waste power lithium batteries and preparing ternary cathode material ) 是由 陈湘萍 康铎之 于 2019-09-18 设计创作，主要内容包括：一种废旧动力锂电池中有价金属选择性提取及三元正极材料再制备的工艺,包括以下步骤；(1)对回收的废旧锂电池进行完全放电,拆解,超声剥离,煅烧和研磨得到所需的LiNi<Sub>1/</Sub><Sub>3</Sub>Mn<Sub>1/3</Sub>CoO<Sub>2</Sub>正极材料；(2)将LiNi<Sub>1/3</Sub>Mn<Sub>1/3</Sub>CoO<Sub>2</Sub>正极材料采用湿法冶金的方法,使用温和的酸和还原剂浸出,控制正极材料和加入酸的比例为20-60mL/g,进一步得到富含锂的浸出液和含有镍钴锰的沉淀；(3)将沉淀用微量的酸和还原剂再次浸出,控制沉淀和加入酸的比例为20-60mL/g,得到富含金属的盐溶液；(4)将金属盐溶液采用共沉淀得到三元前驱体,按前驱体物质的量计添加过量3％-10％锂源,选择温度煅烧,得到电化学性能良好的三元正极材料。本发明可实现金属资源化利用和解决有害垃圾污染问题,成本较低。(A process for selectively extracting valuable metals from waste power lithium batteries and preparing a ternary cathode material comprises the following steps; (1) completely discharging, disassembling, ultrasonically stripping, calcining and grinding the recovered waste lithium battery to obtain the required LiNi 1/ 3 Mn 1/3 CoO 2 A positive electrode material; (2) reacting LiNi 1/3 Mn 1/3 CoO 2 The anode material adopts a hydrometallurgy method, so thatLeaching with mild acid and reducing agent, and controlling the ratio of the anode material to the added acid to be 20-60mL/g, so as to further obtain leachate rich in lithium and precipitate containing nickel, cobalt and manganese; (3) leaching the precipitate with trace amount of acid and reducing agent, and controlling the ratio of precipitate to acid to be 20-60mL/g to obtain metal-rich salt solution; (4) and (2) coprecipitating the metal salt solution to obtain a ternary precursor, adding 3-10% of lithium source in excess according to the mass of the precursor, and calcining at a selected temperature to obtain the ternary cathode material with good electrochemical performance. The invention can realize the resource utilization of metal and solve the problem of harmful garbage pollution, and has lower cost.)

1. A process for selectively extracting valuable metals from waste power lithium batteries and preparing a ternary cathode material is characterized by comprising the following steps;

(1) completely discharging, disassembling, ultrasonically stripping, calcining and grinding the recovered waste lithium battery to obtain the required LiNi_1/3Mn_1/3CoO₂A positive electrode material;

(2) reacting LiNi_1/3Mn_1/3CoO₂The anode material is leached by a hydrometallurgy method by using mild acid and a reducing agent, the ratio of the anode material to the added acid is controlled to be 20-60mL/g, and further leaching solution rich in lithium and precipitate containing nickel, cobalt and manganese are obtained; drying the obtained precipitate in an oven at 80 deg.C for 10 hr, grinding in agate mortar for preservation, and recording the supernatantThe product is large in volume and stored, so that the subsequent ICP test is facilitated;

(3) leaching the precipitate with trace amount of acid and reducing agent, and controlling the ratio of precipitate to acid to be 20-60mL/g to obtain metal-rich salt solution;

(4) and (2) coprecipitating the metal salt solution to obtain a ternary precursor, adding 3-10% of lithium source in excess according to the mass of the precursor, and calcining at a selected temperature to obtain the ternary cathode material with good electrochemical performance.

2. The process for selectively extracting valuable metals from waste power lithium batteries and preparing the ternary positive electrode material according to claim 1, wherein the leaching temperature in the step (2) is as follows: leaching time is as follows at 40-90 deg.C: 2-60min, liquid-solid ratio: 20-60mL/g, stirring speed: 200 and 600 rpm.

3. The process for selectively extracting valuable metals and preparing the ternary positive electrode material from the waste power lithium batteries according to claim 1, wherein the concentration of the acid in the leaching agent in the step (2) is 0.2-3mol/L, the concentration of the reducing agent is 1-5 vol.%, the selected acid is one of inorganic acid or organic acid, hydrochloric acid, phosphoric acid, oxalic acid, citric acid, ascorbic acid and tartaric acid, and the reducing agent is one of hydrogen peroxide, sodium thiosulfate and ascorbic acid.

4. The process for selectively extracting valuable metals from waste power lithium batteries and preparing the ternary positive electrode material according to claim 1, wherein the leaching conditions in the step (3) are as follows: leaching temperature: leaching time is as follows at 50-90 deg.C: 10-50min, liquid-solid ratio: 20-60mL/g, 0.05-0.3mol/L of acid concentration, 0-2 vol.% of reducing agent concentration, one of hydrochloric acid, phosphoric acid, sulfuric acid and nitric acid as leaching acid, and one of hydrogen peroxide, sodium persulfate and ascorbic acid as reducing agent.

5. The process for selectively extracting valuable metals from waste power lithium batteries and preparing the ternary cathode material according to claim 1, wherein in the coprecipitation in the step (4), the pH is 7-12, the concentration of a precipitator is 0.5-2mol/L, the temperature is 20-60 ℃, the reaction and aging time is 6-48 h, the precipitator is one of sodium hydroxide, sodium carbonate and oxalic acid, and the concentration ratio of a metal salt solution to the precipitator is 1: 1.

6. The process for selectively extracting valuable metals from waste power lithium batteries and preparing the ternary cathode material as claimed in claim 1, wherein the calcination temperature in the muffle furnace in the step (4) is 700 ℃ and 1000 ℃ for 10-12 h.

Technical Field

The invention relates to the technical field of effective recovery of valuable metals of waste batteries, in particular to a process for selectively extracting valuable metals and preparing a ternary positive electrode material from waste power lithium batteries.

Background

With the rapid development of science and technology, lithium ion batteries have the advantages of high energy, relatively long service life and the like, and are widely used in life of people, but the service life is only 2-3 years due to excessive charging and discharging times, so that the waste output is also excessive. The metals contained in the lithium ion battery are all harmful metals, so that the environment ecology is polluted non-negligibly, the manganese, nickel, cobalt and lithium and other metals are effectively recycled at present, the environment pollution can be effectively relieved, the recycling can be realized, the problem of resource shortage is solved, and the waste classification developed in China at present can more effectively promote the recycling of waste batteries.

At present, the treatment technology of waste lithium batteries is a hydrometallurgy technology, metals in a positive electrode material are completely leached out by using high-concentration inorganic acid or organic acid such as hydrochloric acid and sulfuric acid, but the problem of separation of subsequent metals is still complex, the metals cannot be effectively recycled, the cost of the high-concentration acid is high, the economic benefit is poor, and how to treat the high-efficiency recycled metal resources becomes an urgent problem at present.

Disclosure of Invention

In order to solve the technical problems, the invention aims to provide a process for selectively extracting valuable metals from waste power lithium batteries and preparing a ternary cathode material again, a novel method for effectively realizing short-range coupling selective extraction of Li and repair and regeneration of the cathode material by adopting a method combining leaching and material repair is adopted, the method can realize metal resource utilization and solve the problem of harmful garbage pollution, and the cost is low.

In order to achieve the purpose, the invention adopts the technical scheme that:

a process for selectively extracting valuable metals from waste power lithium batteries and preparing a ternary cathode material comprises the following steps;

(1) completely discharging, disassembling, ultrasonically stripping, calcining and grinding the recovered waste lithium battery to obtain the required LiNi_1/3Mn_1/3CoO₂A positive electrode material;

(2) reacting LiNi_1/3Mn_1/3CoO₂The anode material is leached by a hydrometallurgy method by using mild acid and a reducing agent, the ratio of the anode material to the added acid is controlled to be 20-60mL/g, and further leaching solution rich in lithium and precipitate containing nickel, cobalt and manganese are obtained; drying the obtained precipitate in an oven at 80 ℃ for 10 hours, grinding and storing the precipitate in an agate mortar, recording the volume and storing the supernatant, and facilitating the subsequent ICP test;

(3) leaching the precipitate with trace amount of acid and reducing agent, and controlling the ratio of precipitate to acid to be 20-60mL/g to obtain metal-rich salt solution;

(4) and (2) coprecipitating the metal salt solution to obtain a ternary precursor, adding 3-10% of lithium source in excess according to the mass of the precursor, and calcining at a selected temperature to obtain the ternary cathode material with good electrochemical performance.

The leaching temperature in the step (2) is as follows: leaching time is as follows at 40-90 deg.C: 2-60min, liquid-solid ratio: 20-60mL/g, stirring speed: 200 and 600 rpm.

In the step (2), the concentration of acid in the leaching agent is 0.2-3mol/L, the concentration of the reducing agent is 1-5 vol.%, the selected acid is one of inorganic acid or organic acid, hydrochloric acid, phosphoric acid, oxalic acid, citric acid, ascorbic acid and tartaric acid, and the reducing agent is one of hydrogen peroxide, sodium thiosulfate and ascorbic acid.

The leaching conditions in the step (3) are as follows: leaching temperature: leaching time is as follows at 50-90 deg.C: 10-50min, liquid-solid ratio: 20-60mL/g, 0.05-0.3mol/L of acid concentration, 0-2 vol.% of reducing agent concentration, one of hydrochloric acid, phosphoric acid, sulfuric acid and nitric acid as leaching acid, and one of hydrogen peroxide, sodium persulfate and ascorbic acid as reducing agent.

In the coprecipitation in the step (4), the pH is 7-12, the concentration of a precipitator is 0.5-2mol/L, the temperature is 20-60 ℃, the reaction and aging time is 6-48 h, the precipitator is one of sodium hydroxide, sodium carbonate and oxalic acid, and the ratio of the concentration of a metal salt solution to the concentration of the precipitator is 1: 1.

In the step (4), the calcination temperature in a muffle furnace is 700-1000 ℃, and the time is 10-12 h. .

The invention has the beneficial effects that:

(1) the method has the advantages of simple and feasible operation flow, low temperature, low power, low energy consumption, no generation of other harmful gases, economy and environmental protection;

(2) the step leaching can effectively recover metals, solve the problem that the metals are difficult to separate, save the recovery cost and avoid secondary pollution due to the low-concentration acid.

(3) For transition valuable metals, because of similar chemical properties, it is currently difficult and complicated to separate each metal individually, so that these metals can be sufficiently reused while solving the problem of resource shortage by performing the repair by a simple method.

Drawings

FIG. 1 is a flow chart of selective extraction of Li from waste lithium batteries and regeneration of materials.

Figure 2 is an XRD pattern of a precipitated product and a ternary material obtained by leaching under different conditions with certain acid.

FIG. 3 is an SEM image of a precursor and a ternary material obtained by acid leaching to obtain a precipitated product and regeneration preparation.

FIG. 4 is a graph of LiNi synthesized at different temperatures_1/3Mn_1/3Co_1/3O₂The first charge-discharge curve diagram of the anode material.

FIG. 5 is a graph of LiNi synthesized at different temperatures_1/3Mn_1/3Co_1/3O₂Positive electrode material multiplying power test chart.

Detailed Description

The present invention will be described in further detail with reference to the accompanying drawings.

In the invention, the core steps of separation-re-leaching-regeneration are mainly adopted, firstly, a certain acid with mild low concentration is used for carrying out a single-factor experiment, and the optimal metal separation condition is gradually determined by analyzing the acid concentration, the reaction temperature, the liquid-solid ratio, the reducing agent amount and the leaching time; secondly, a trace amount of certain acid is adopted, factor conditions and kinetic experiments are further optimized, and the fact that metal ions of nickel, cobalt and manganese are reduced to 2-valent metal ions is determined, so that abundant raw materials can be provided for preparing a precursor in the next step; finally, by using a traditional simple coprecipitation method, the proportion of each metal in the metal salt solution is properly adjusted to obtain a precursor with a more excellent structure, and the ternary material with good electrochemical performance is prepared. Compared with other separation and recovery processes, the process has the advantages of mild reaction conditions, low temperature, short time, less acid consumption, high efficiency and high separation efficiency, can recycle valuable metals, and meets the aims of economy, high efficiency and environmental protection of recovery.

In the preferable embodiment of (2) in the present invention, the leaching conditions are: leaching temperature: leaching time is as follows at 40-90 deg.C: 2-60min, liquid-solid ratio: 20-60mL/g, stirring speed: 200 and 600 rpm. The concentration of certain acid in the leaching agent is 0.2-3mol/L, and the concentration of the reducing agent is 1-5 vol.%. In a preferred embodiment, the conditions are: the time is 30-60min, the temperature is 60-90 ℃, the stirring speed is 400rpm, and the acid concentration is 0.4-1.0 mol/L.

In the (3) preferred embodiment of the present invention, the leaching conditions are: leaching temperature: leaching time is as follows at 50-90 deg.C: 10-50min, liquid-solid ratio: 20-60mL/g, acid concentration 0.05-0.25mol/L, reducing agent concentration 0-2 vol.%, preferable scheme, the conditions are: the time is 30-60min, the temperature is 50-80 ℃, and the acid concentration is 0.05-0.2 mol/L.

In a preferred embodiment of (4) of the present invention, the precursor preparation conditions are: the pH is 7-12, the concentration of the precipitator is 0.5-2mol/L, the temperature is 20-60 ℃, the reaction and aging time is 6-48 h, the calcination temperature of the synthetic ternary material is 700-1000 ℃, and the preferable scheme is as follows: the preparation conditions of the precursor are as follows: the pH value is 10-12, the concentration of the precipitator is 1-2mol/L, the temperature is 30-60 ℃, the reaction and aging time is 8-24h, and the muffle furnace calcination temperature is 800-1000 ℃.

All experimental conditions of the single-factor experiment are subjected to 3 parallel experiments, and the average value of the 3 experiments is taken as the final experimental result.

As shown in fig. 2: different leaching conditions result in the XRD pattern of the precipitation and commercial ternary material (leaching conditions: 0.6mol/L acid, 80 ℃, 4 vol.% reducing agent, 20mL/g, 30 min; (2):0.6mol/L acid, 80 ℃, 4 vol.% reducing agent, 40mL/g, 20 min; (3):0.6mol/L acid, 80 ℃, 1 vol.% reducing agent, 40mL/g, 30 min; (4):0.6mol/L acid, 80 ℃, 4 vol.% reducing agent, 40mL/g, 30 min.)

As shown in fig. 3: a, B and C are respectively precipitates obtained by leaching certain acid under the optimal condition, coprecipitating to prepare a precursor, and synthesizing LiNi at the optimal calcination temperature_1/3Mn_1/3Co_1/3O₂SEM image of the cathode material.

As shown in fig. 4: synthesis of LiNi at different temperatures_1/3Mn_1/3Co_1/3O₂The first charge-discharge curve diagram of the anode material.

As shown in fig. 5: synthesis of LiNi at different temperatures_1/3Mn_1/3Co_1/3O₂Positive electrode material multiplying power test chart.