A rapid and selective method for extracting lithium from waste power battery black powder

Abstract

The present invention discloses a method for rapid selective extraction of lithium from waste power battery black powder, and belongs to the technical field of lithium battery material recovery. The preparation method comprises the following steps: ball-milling the waste battery black powder to a certain particle size, adding a corresponding solvent and a lithium extractant, stabilizing the reaction system at a certain temperature, adjusting the pH of the reaction system, stirring and turning on ultrasound, so as to selectively leach the lithium element in a relatively short time. After the extraction reaction is completed, filtering with a filtering device to obtain a lithium selective extraction solution and a filter residue, respectively. The method for rapid selective extraction of lithium from waste power battery black powder provided by the present invention can rapidly and selectively extract the lithium from waste power battery black powder in a relatively short time, thereby improving the production capacity of the reaction production line; reducing the impurity content in the lithium extraction solution, shortening the process of impurity removal in the latter stage, and being conducive to reducing process costs and improving the competitiveness of the production line.

Description

Technical Field

[0001] The invention belongs to the technical field of lithium battery material recovery, and in particular relates to a method for rapidly and selectively extracting lithium from black powder of waste power batteries. Background Art

[0002] A large amount of retired positive electrode materials are produced during the entire life cycle of lithium-ion batteries, which are in urgent need of recycling. After disassembly, crushing, high-temperature calcination and screening, waste lithium-ion batteries become corresponding battery black powder, which contains positive and negative electrode materials and impurities such as copper and aluminum, and is in urgent need of recycling. The key technology in the wet recycling and recycling of waste power battery black powder has become an inevitable choice for promoting the green and sustainable development of new energy technologies. The leaching process is mainly aimed at the recovery of valuable metal elements in battery materials. It mainly uses acid and metal elements in battery materials to react to generate soluble salts, and further separates and recovers different metal elements by separation. However, due to the long acid leaching time and the inability to achieve selective leaching of metals, a large amount of water will be consumed in the later separation and impurity removal process of different metal elements, which will bring great pressure to environmental protection.

[0003] Chinese invention CN114583316A discloses a method and application for recycling lithium ion batteries, which includes the following steps: mixing waste lithium ion batteries with waste NMP, ultrasonic stirring, solid-liquid separation, obtaining filter residue and first filtrate; removing the filter residue from organic, salt washing, sorting, obtaining battery powder; acid leaching the battery powder to obtain leachate and graphite slag, taking the leachate, adding an oxidant to react, then adding a phosphate-containing iron removal agent to mix and react, adjusting pH, solid-liquid separation, obtaining iron phosphate and a second filtrate; adding a dephosphorizing agent to the second filtrate to react, extracting and removing impurities, and precipitating to obtain a precursor. The method of the present invention does not generate hydrogen during the recovery process, can also realize the separation of positive electrode material / negative electrode material from black powder, and uses phosphate to remove iron, prevents iron colloid from carrying valuable metals, and improves the metal recovery rate.

[0004] The present invention provides a method for rapid and selective extraction of lithium from waste power battery black powder. The main technical problem solved is to overcome the shortcomings of the above background technology, that is, the long acid leaching time and the inability to selectively leach lithium metal, and provide a method for rapid and selective extraction of lithium from waste power battery black powder. The method for rapid and selective extraction of lithium from waste power battery black powder provided by the present invention can rapidly and selectively extract lithium from waste power battery black powder in a relatively short time, thereby improving the production capacity of the reaction production line; reducing the impurity content in the lithium extraction solution, shortening the process of impurity removal in the latter stage, and being conducive to reducing process costs and improving the competitiveness of the production line. Summary of the invention

[0005] In order to solve the above technical problems, the present invention provides a method for rapid and selective extraction of lithium from waste power battery black powder, so that the lithium from waste power battery black powder can be rapidly and selectively extracted in a relatively short time, thereby improving the production capacity of the reaction production line; reducing the impurity content in the lithium extraction solution, shortening the subsequent impurity removal process, and being conducive to reducing process costs and improving the competitiveness of the production line.

[0006] To achieve the above object, the technical solution adopted by the present invention is as follows:

[0007] A method for rapid and selective extraction of lithium from waste power battery black powder comprises the following steps:

[0008] The black powder is ball-milled using a ball mill;

[0009] The ball-milled black powder is transferred to the reaction kettle by using a material transfer device;

[0010] Add solvent to the reactor at a certain liquid-to-solid ratio and start stirring;

[0011] The temperature in the reactor is kept constant by using a thermostat;

[0012] Adding a certain mass fraction of extractant into the reactor;

[0013] The pH of the reaction system is adjusted by acid to maintain a stable pH throughout the extraction process. The reaction system is a suspension of black powder, solvent, extractant and acid.

[0014] Turn on ultrasound and the extraction process begins;

[0015] After the extraction process is completed, the suspension is filtered using a filtering device to obtain a lithium selective extraction solution and a filter residue, respectively.

[0016] Preferably, the type of the waste battery black powder is one or more of NCM ternary, transition metal multi-element, lithium cobalt oxide, lithium manganese oxide, lithium-rich manganese-based and lithium iron phosphate.

[0017] Preferably, the ball milling device is one or more of a ball mill, a sand mill, a grinder or a crusher, and a pneumatic crusher.

[0018] Preferably, the particle size of the black powder is in the range of 0.01-500 μm.

[0019] Preferably, the material transfer device includes one or more of a conveyor belt, negative pressure vacuum conveying, and a height difference slope.

[0020] Preferably, the liquid-to-solid ratio ranges from 1:1 to 6:1.

[0021] Preferably, the lithium extractant is one or more of an organic acid, an inorganic acid, a polymer compound, and an alkaline compound.

[0022] Preferably, the pH range of the reaction system is 0.5-3.0.

[0023] Preferably, the extraction process takes 0.2-4 hours.

[0024] Compared with the prior art, the beneficial effect of the present invention is that it can quickly and selectively extract lithium elements from waste power battery black powder in a relatively short time, thereby improving the production capacity of the reaction production line; reducing the impurity content in the lithium extraction solution, shortening the subsequent impurity removal process, and helping to reduce process costs and improve the competitiveness of the production line. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 The present invention is a process flow chart of a method for rapid and selective extraction of lithium from waste power battery black powder according to an embodiment of the present invention. DETAILED DESCRIPTION

[0026] The following is a detailed description of an embodiment of the present invention. This embodiment is implemented on the premise of the technical solution of the present invention, and a detailed implementation method and a specific operation process are given, but the protection scope of the present invention is not limited to the following embodiment.

[0027] Example 1

[0028] The present invention provides a method for rapid selective extraction of lithium from waste power battery black powder, taking the rapid extraction of lithium from waste ternary battery black powder as an example. Figure 1 As shown, the specific steps include:

[0029] Step 1, weigh 100kg of ternary black powder of waste ternary power batteries (containing 60wt% of ternary positive electrode material, 37wt% of negative electrode graphite, and 3wt% of copper and aluminum), add it into a ball mill, put in 50kg of zirconium balls, ball mill at 200rpm for 30min, take it out and sieve out the zirconium balls; collect the black powder under the sieve, and test the particle size D50 to be 10μm;

[0030] Step 2: Use a negative pressure vacuum device to pump the black powder from step 1 to a 1m 3 In the reactor, a circulating water heating device was used to maintain the reaction system at 65°C, 400L of deionized water was added, atmospheric pressure was maintained, and the stirring speed was turned on at 400rpm;

[0031] Step 3, add 1.2L sulfuric acid (concentration 30wt%) to adjust the pH of the reaction system to 2.5, add 20L of lithium metal extractant Li-985 (90wt% tributyl phosphate; 10wt% ion additive (styrene maleic anhydride resin)); turn on the ultrasonic generator, power 1400W, and extract for 20min.

[0032] Step 4: After the selective extraction is completed, the suspension is separated by a centrifuge to obtain a lithium solution and a filter residue. The concentration of the lithium solution is Li + 2g / L. The composition of the filter residue is: 40wt% nickel-cobalt-manganese oxide, 27wt% graphite residue, 3wt% copper-aluminum residue, and 30wt% water.

[0033] Example 2

[0034] Step 1, weighing 100kg of ternary black powder of waste ternary power batteries (containing 60wt% of ternary positive electrode material, 37wt% of negative electrode graphite, and 3wt% of copper and aluminum);

[0035] Step 2: Use a negative pressure vacuum device to pump the black powder from step 1 to a 1m 3 In the reactor, a circulating water heating device was used to maintain the reaction system at 65°C, 400L of deionized water was added, atmospheric pressure was maintained, and the stirring speed was turned on at 400rpm;

[0036] Step 3, adding 1.2L sulfuric acid (concentration 30wt%) to adjust the pH of the reaction system to 2.5, and extracting for 120min;

[0037] Step 4: After the selective extraction is completed, the suspension is separated by a centrifuge to obtain a lithium solution (Li + 1.8g / L,Al 3+ 0.081g / L,Cu 2+ 0.032g / L) and filter residue (nickel cobalt manganese oxide 40wt%, graphite slag 27wt%, copper aluminum slag 3wt%, water 30wt%).

[0038] Compared with Example 1, Example 2 reduces the ball milling step, does not add lithium metal extractant, and does not turn on ultrasound during the extraction process, resulting in a longer extraction time and the extract containing impurities.

[0039] It will be easily understood by those skilled in the art that the above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A method for rapid and selective extraction of lithium from waste power battery black powder. It is characterized in that The following steps are involved: The black powder is ball-milled using a ball mill; The ball-milled black powder is transferred to the reaction kettle by using a material transfer device; Add solvent to the reactor and start stirring; The temperature in the reactor is kept constant by using a thermostat; adding an extractant to the reaction kettle; Using acid to adjust the pH of the reaction system, the reaction system is a suspension of black powder, solvent, extractant and acid; Turn on ultrasound and the extraction process begins; After the extraction process is completed, the suspension is filtered using a filtering device to obtain a lithium selective extraction solution and a filter residue respectively; the extracting agent is tributyl phosphate and styrene maleic anhydride resin; The type of the waste power battery black powder is one or more of NCM ternary, lithium cobalt oxide, lithium manganese oxide and lithium iron phosphate; the particle size range of the black powder is 0.01-500 μm, and the pH range of the reaction system is 0.5-3.

0.

2. A method for rapid and selective extraction of lithium from waste power battery black powder according to claim 1, It is characterized in that The ball milling device is a ball mill.

3. According to claim 1, a method for rapid and selective extraction of lithium from waste power battery black powder, It is characterized in that The material transfer device includes one or more of a conveyor belt, a negative pressure vacuum device, and a height difference slope.

4. According to claim 1, a method for rapid and selective extraction of lithium from waste power battery black powder, It is characterized in that The liquid-to-solid ratio of the solvent to the black powder ranges from 1L:1kg to 6L:1kg.

5. A method for rapid and selective extraction of lithium from waste power battery black powder according to claim 1, It is characterized in that The extraction time is 0.2-4h.

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