Alkaline leaching recovery method of waste oxide battery cathode material

Abstract

The application provides a kind of alkali leaching recovery method of waste oxide battery positive material, comprising: with the mixed aqueous solution of glycine, alkali and oxalate as the alkali leaching bottom solution, adding waste oxide battery positive material, soluble ferrous salt into the alkali leaching bottom solution, and carrying out leaching reaction. The method can realize the reduction of high-valence metal in oxide waste lithium ion battery positive material by using the reducing property of ferrous ion, can effectively improve the leaching efficiency of valuable metal, shorten the time of alkali leaching, and obtain higher metal leaching rate. And the leaching method can effectively avoid the entry of iron ion into liquid phase in the leaching process, causing a series of problems such as difficult separation of valuable metal in subsequent process, the reagent used is simple, the method condition is simple and easy to control, the energy consumption is low, the efficiency is high, and it has considerable industrial application prospect.

Description

Technical Field

[0001] This invention belongs to the field of lithium-ion battery recycling technology, specifically relating to an alkaline leaching recycling method for waste oxide battery cathode materials. Background Technology

[0002] In recent years, my country's new energy vehicle industry has experienced explosive growth. Consequently, a large number of power batteries are facing retirement, making the recycling and reuse of these batteries of significant practical importance. Currently, the main methods for recycling valuable metals from lithium-ion batteries are pyrometallurgical and hydrometallurgical processes. Pyrometallurgical methods are relatively simple, but suffer from high energy consumption and large emissions. Hydrometallurgical methods mainly include acid leaching and alkaline leaching. Acid leaching typically uses hydrochloric acid, sulfuric acid, nitric acid, etc., as leaching solvents, which may produce toxic and harmful gases (sulfur dioxide, nitrogen dioxide, etc.), and acidic waste is difficult to treat, making it environmentally unfriendly. Furthermore, acid leaching easily introduces various impurities, making subsequent valuable metal reuse processes more complex. Alkaline leaching typically uses ammonia as a leaching solvent, possessing the advantage of selective metal leaching, but suffers from a slow leaching rate. Additionally, ammonia consumption is large, and under heating conditions, ammonia is highly volatile, placing higher demands on the sealing of equipment and devices.

[0003] Chinese patent CN107017443A achieves the recovery of valuable metals from waste lithium-ion batteries through multiple processes, including battery crushing, pre-roasting, reduction roasting, water leaching, ammonia oxidation leaching, extraction, back-extraction, acid oxidation leaching, and extraction purification. The extraction system of this method is extremely complex, and the process is very lengthy.

[0004] Chinese patent CN109193057A describes a method for recovering valuable metals from spent ternary lithium batteries by pressurized ammonia leaching, specifically lithium, nickel, and cobalt. This method requires leaching in a high-pressure reactor at a predetermined pressure (0.6-1.5 MPa), and necessitates the use of a relatively large amount of ammonia (5-12 mol / L). Summary of the Invention

[0005] To address the aforementioned technical problems, the present invention aims to provide an alkaline leaching method for recycling waste oxide battery cathode materials.

[0006] In response to the technical problems existing in the prior art, the applicant has discovered through extensive research that using a mixed solution of glycine-alkali-oxalate as the leaching base and ferrous salt as the reducing agent can achieve a high leaching rate under mild reaction conditions and with a short process.

[0007] To achieve the above objectives, the present invention proposes the following solution:

[0008] A method for alkaline leaching and recycling of waste oxide battery cathode materials includes: using a mixed aqueous solution of glycine, alkali and oxalate as an alkaline leaching base solution, adding waste oxide battery cathode materials and soluble ferrous salt to the alkaline leaching base solution, and carrying out a leaching reaction; wherein the alkali is sodium hydroxide and / or potassium hydroxide.

[0009] Preferably, the process also includes solid-liquid separation of the material obtained from the leaching reaction to obtain leachate and leaching residue.

[0010] Preferably, the alkaline leaching solution contains 0.01-0.3 mol / L of alkali and 0.05-1 mol / L of glycine.

[0011] Preferably, the pH of the alkaline leaching solution is controlled between 8 and 12.

[0012] Preferably, the oxalate is one or more of potassium oxalate, sodium oxalate, and ammonium oxalate; the concentration of oxalate in the alkaline leachate is 0.01~0.5 mol / L.

[0013] Preferably, the leaching reaction temperature is 30~90℃; the leaching reaction time is 1~10 h; the leaching reaction is carried out under stirring; and the stirring speed is 100~500 r / min.

[0014] Preferably, the soluble ferrous salt is selected from one or two of ferrous chloride and ferrous nitrate; the molar ratio of iron to waste oxide cathode powder in the soluble ferrous salt is 1:1 to 4:1.

[0015] Preferably, the cathode material of the waste oxide battery is selected from Li. 1+a (Ni x Co y M 1-x-y O2, Na 1+a (Ni x Co y M 1-x-y O2, Li(Ni) p Mn q Co 2-p-q-r M r O4, Na(Ni) p Mn q Co 2-p-q-r M r O4 and one or more of them; wherein 0≤a≤0.3, 0≤x≤1, 0≤y≤1, 0<x+y≤1; 0≤p≤2, 0≤q≤2, 0<p+q≤2, 0≤r<2; M is selected from one or more of Fe, Ni, Co, Mn, Al, and V.

[0016] As a preferred option, waste oxide battery cathode material is added to an alkaline leaching solution with a solid-liquid ratio controlled between 1 and 50 g / L.

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

[0018] In the leaching method of this invention, a special alkaline system is used as the leaching base solution. The reducing property of ferrous ions is utilized to reduce high-valence metals in oxide-based waste lithium-ion battery cathode materials, effectively improving the leaching efficiency of valuable metals, shortening the alkaline leaching time, and achieving a high metal leaching rate. Furthermore, this leaching method effectively avoids the entry of iron ions into the liquid phase during the leaching process, preventing subsequent difficulties in separating valuable metals. The reagents used are simple, the method conditions are easy to control, energy consumption is low, efficiency is high, and it has considerable industrial application prospects. Attached Figure Description

[0019] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0020] Figure 1 The waste ternary cathode material Li(Ni) processed in Example 2 of this invention 1 / 3 Co 1 / 3 Mn 1 / 3 Scanning electron microscope image of O2;

[0021] Figure 2 This is a scanning electron microscope image of the leaching residue obtained in Example 2 of the present invention. Detailed Implementation

[0022] This invention provides an alkaline leaching recycling method for waste oxide battery cathode materials, comprising: using a mixed aqueous solution of glycine, alkali and oxalate as an alkaline leaching base solution, adding waste oxide battery cathode materials and soluble ferrous salt to the alkaline leaching base solution, and carrying out a leaching reaction; wherein the alkali is sodium hydroxide and / or potassium hydroxide.

[0023] In some embodiments, the leaching material is further subjected to solid-liquid separation to obtain leachate and leaching residue.

[0024] In some preferred embodiments, the concentration of alkali in the alkaline leaching solution is 0.01~0.3 mol / L, for example, 0.05 mol / L, 0.1 mol / L, 0.15 mol / L, 0.2 mol / L, 0.25 mol / L, etc.

[0025] In some preferred embodiments, the concentration of glycine is 0.05~1 mol / L, for example 0.1 mol / L, 0.2 mol / L, 0.3 mol / L, 0.4 mol / L, 0.5 mol / L, 0.6 mol / L, 0.7 mol / L, 0.8 mol / L, 0.9 mol / L, etc.

[0026] In some preferred embodiments, the pH of the alkaline leaching solution is controlled between 8 and 12, such as 8.5, 9, 9.5, 10, 10.5, 11, 11.5, etc.

[0027] In some embodiments, the oxalate is one or more of potassium oxalate, sodium oxalate, and ammonium oxalate.

[0028] In some preferred embodiments, the concentration of oxalate in the alkaline leachate is 0.01~0.5 mol / L, for example, 0.05 mol / L, 0.1 mol / L, 0.15 mol / L, 0.2 mol / L, 0.25 mol / L, 0.3 mol / L, 0.35 mol / L, 0.4 mol / L, 0.45 mol / L, etc.

[0029] In some preferred embodiments, the leaching reaction temperature is 30~90℃, for example 40℃, 50℃, 60℃, 70℃, 80℃, etc.; the leaching reaction time is 1~10 h, for example 2h, 3h, 4h, 5h, 6h, 7h, 8h, 9h, etc.; the leaching reaction is carried out under stirring; the stirring speed is 100~500 r / min, for example 200 r / min, 300 r / min, 400 r / min, 450 r / min, etc.

[0030] In some preferred embodiments, the soluble ferrous salt is selected from one or more of ferrous chloride and ferrous nitrate; the molar ratio of iron to waste oxide cathode powder in the soluble ferrous salt is 1:1 to 4:1, for example, 1.5:1, 2:1, 2.5:1, 3:1, 3.5:1, 4:1, etc.

[0031] Various oxide cathode materials, including lithium-ion battery oxide cathode materials and sodium-ion battery oxide cathode materials, can be used as treatment targets. In some preferred embodiments, the waste oxide battery cathode material is selected from Li... 1+a (Ni x Co y M 1-x-y O2, Na 1+a (Ni x Co y M 1-x-yO2, Li(Ni) p Mn q Co 2-p-q-r M r O4, Na(Ni) p Mn q Co 2-p-q-r M r O4 and one or more of them; wherein 0≤a≤0.3, 0≤x≤1, 0≤y≤1, 0<x+y≤1; 0≤p≤2, 0≤q≤2, 0<p+q≤2, 0≤r<2; M is selected from one or more of Fe, Ni, Co, Mn, Al, and V.

[0032] In some preferred embodiments, the waste oxide battery cathode material is added to the alkaline leaching solution with a solid-liquid ratio controlled between 1 and 50 g / L, for example, 5 g / L, 10 g / L, 15 g / L, 20 g / L, 25 g / L, 30 g / L, 35 g / L, 40 g / L, 45 g / L, etc.

[0033] To facilitate understanding of the present invention, the invention will be described more fully and in detail below with reference to the accompanying drawings and preferred embodiments, but the scope of protection of the present invention is not limited to the following specific embodiments.

[0034] Unless otherwise defined, all technical terms used herein have the same meaning as commonly understood by those skilled in the art. The technical terms used herein are for the purpose of describing particular embodiments only and are not intended to limit the scope of the invention.

[0035] Unless otherwise specified, all raw materials, reagents, instruments and equipment used in this invention can be purchased from the market or prepared by existing methods.

[0036] Example 1

[0037] (1) Dispose of waste NCM523 (Li(Ni 0.5 Co 0.2 Mn 0.3 The ternary lithium battery was discharged, then manually disassembled to separate the positive electrode aluminum foil, and then peeled off to obtain the positive electrode material (waste ternary positive electrode material).

[0038] (2) Add 1.1260 g glycine, 0.1200 g sodium hydroxide and 3.8136 g potassium oxalate to 300 ml distilled water to prepare a 300 mL mixed solution;

[0039] (3) Heat the above mixed solution to 80°C, stirring throughout the process at a speed of 300 r / min;

[0040] (4) Add 2 g of waste ternary cathode material Li(Ni) 0.5 Co 0.2 Mn 0.3 Add 2.6237 g of ferrous chloride to O2, and stop stirring and heating after reacting for 3 hours;

[0041] (5) A vacuum filtration device is used to separate the leachate and the leach residue. The leachate is diluted 100 times and used for ICP detection, while the morphology of the leach residue is observed by scanning electron microscopy.

[0042] ICP results showed that the leaching rates of each metal reached: Li 99.5%, Ni 99.6%, Co 89.1%, and Mn 52.3%, while Fe, Al, and Cu did not enter the filtrate.

[0043] Example 2

[0044] (1) Dispose of waste NCM111 (Li(Ni 1 / 3 Co 1 / 3 Mn 1 / 3 The ternary lithium battery was discharged, then manually disassembled to separate the positive electrode aluminum foil, and then peeled off to obtain the positive electrode material (waste ternary positive electrode material).

[0045] (2) Add 0.7507 g glycine, 0.1600 g sodium hydroxide and 1.3936 g sodium oxalate to 200 ml distilled water to prepare a 200 mL mixed solution;

[0046] (3) Heat the above mixed solution to 80°C and keep it at that temperature, stirring throughout the process and controlling the speed at 250 r / min;

[0047] (4) Add 1 g of waste ternary cathode material Li(Ni) 1 / 3 Co 1 / 3 Mn 1 / 3 Add 1.3148 g of ferrous chloride to O2, and react at 80°C. Stop stirring and heating after 2 hours of reaction.

[0048] (5) A vacuum filtration device is used to separate the leachate and the leach residue. The leachate is diluted 100 times and used for ICP detection, while the morphology of the leach residue is observed by scanning electron microscopy.

[0049] ICP results showed that the leaching rates of each metal reached: Li 99.9%, Ni 99.9%, Co 92.4%, and Mn 55.6%, while Fe, Al, and Cu did not enter the filtrate.

[0050] Images were taken using a scanning electron microscope. Figure 1 as well as Figure 2They represent waste ternary cathode materials Li(Ni) 1 / 3Co 1 / 3 Mn 1 / 3 The morphology of O2 and the leaching residue after the reaction shows that the secondary spherical particle structure of the material has completely disappeared. Figure 1 The waste ternary cathode material Li(Ni) before the reaction 1 / 3 Co 1 / 3 Mn 1 / 3 The SEM image of O2 shows a secondary spherical particle structure, which is an irregular spherical structure with varying particle sizes, ranging from 2 to 20 micrometers. Figure 2 The image shows an SEM image of the leaching residue after the reaction. It can be seen that the secondary spherical particle structure has completely disappeared, indicating that the leaching was relatively thorough.

[0051] Example 3

[0052] (1) Dispose of waste NCM811 (Li(Ni 0.8 Co 0.1 Mn 0.1 The ternary lithium battery was discharged, then manually disassembled to separate the positive electrode aluminum foil, and then peeled off to obtain the positive electrode material (waste ternary positive electrode material).

[0053] (2) Add 3.0026 g glycine, 0.4800 g sodium hydroxide and 3.8222 g ammonium oxalate to 400 ml distilled water to prepare a 400 mL mixed solution;

[0054] (3) Heat the above mixed solution to 60°C, stirring throughout the process and controlling the speed at 350 r / min;

[0055] (4) Add 3 g of waste ternary cathode material Li(Ni) 0.8 Co 0.1 Mn 0.1 Add 5.8559 g of ferrous chloride to O2, and react at 60°C. Stop stirring and heating after 4 hours of reaction.

[0056] (5) A vacuum filtration device is used to separate the leachate and the leach residue. The leachate is diluted 100 times and used for ICP detection, while the morphology of the leach residue is observed by scanning electron microscopy.

[0057] ICP results showed that the leaching rates of each metal reached: Li 98.2%, Ni 99.8%, Co 85.9%, and Mn 51.5%, while Fe, Al, and Cu did not enter the filtrate.

[0058] Example 4

[0059] (1) Dispose of waste NCM111 (Li(Ni1 / 3 Co 1 / 3 Mn 1 / 3 The ternary lithium battery was discharged, then manually disassembled to separate the positive electrode aluminum foil, and then peeled off to obtain the positive electrode material (waste ternary positive electrode material).

[0060] (2) Add 15.014 g glycine, 1.6000 g sodium hydroxide and 5.360 g sodium oxalate to 200 ml distilled water to prepare a 200 mL mixed solution;

[0061] (3) Heat the above mixed solution to 50°C and keep it at that temperature, while mechanically stirring throughout the process and controlling the speed at 500 r / min;

[0062] (4) Add 10 g of waste ternary cathode material Li(Ni) 1 / 3 Co 1 / 3 Mn 1 / 3 Add 19.013 g of ferrous chloride to O2, and react at 50°C. Stop stirring and heating after 9 hours of reaction.

[0063] (5) A vacuum filtration device is used to separate the leachate and the leach residue. The leachate is diluted 100 times and used for ICP detection, while the morphology of the leach residue is observed by scanning electron microscopy.

[0064] ICP results showed that the leaching rates of each metal reached: Li 97.7%, Ni 96.9%, Co 83.1%, and Mn 49.3%, while Fe, Al, and Cu did not enter the filtrate.

[0065] Example 5

[0066] (1) Add 13.5128 g glycine, 3.1680 g sodium hydroxide and 19.8972 g potassium oxalate to 300 ml distilled water to prepare a 300 mL mixed solution;

[0067] (2) Heat the above mixed solution to 50°C, and mechanically stir throughout the process at a speed of 300 r / min;

[0068] (3) Add 8g of waste ternary cathode material Li(Ni) 1 / 3 Co 1 / 3 Mn 1 / 3 Add 10.14 g of ferrous chloride to O2, and react at 50°C. Stop stirring and heating after 8 hours of reaction.

[0069] (4) A vacuum filtration device is used to separate the leachate and the leach residue. The leachate is diluted 100 times and used for ICP detection, while the morphology of the leach residue is observed by scanning electron microscopy.

[0070] ICP results showed that the leaching rates of each metal reached: Li 98.3%, Ni 97.5%, Co 85.1%, and Mn 49.6%, while Fe, Al, and Cu did not enter the filtrate.

[0071] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the principle of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A method for recovering a positive electrode material of a waste oxide battery by alkaline leaching, characterized by, The application relates to a method for recycling waste oxide positive electrode materials. The application discloses a method for recycling waste oxide battery cathode material, which comprises the following steps: taking a mixed aqueous solution of glycine, alkali and oxalate as an alkaline leaching bottom liquid, adding waste oxide battery cathode material and soluble ferrous salt into the alkaline leaching bottom liquid to perform a leaching reaction; the alkali is sodium hydroxide and / or potassium hydroxide; the concentration of glycine in the alkaline leaching bottom liquid is 0.05-1 mol / L; the oxalate is one or more of potassium oxalate and sodium oxalate, and the concentration of the oxalate in the alkaline leaching bottom liquid is 0.01-0.5 mol / L; the pH of the alkaline leaching bottom liquid is controlled to be 8-12; the waste oxide battery cathode material is selected from one or more of Li(Ni 1+a (Ni x Co y M 1-x-y )O2, Na(Ni 1+a (Ni x Co y M 1-x-y )O2, Li(Ni p Mn q Co 2-p-q-r M r )O4 and Na(Ni p Mn q Co 2-p-q-r M r )O4; wherein 0≤a≤0.3, 0≤x≤1, 0≤y≤1, 0<x+y≤1; 0≤p≤2, 0≤q≤2, 0<p+q≤2, 0≤r<2; M is selected from one or more of Fe, Ni, Co, Mn, Al and V. p 2. The method of claim 1, wherein the spent oxide battery cathode material is recovered by the alkaline leaching process, characterized by, The method further comprises solid-liquid separation of the material obtained through the leaching reaction to obtain leaching liquid and leaching residue.

3. The method for recovering a positive electrode material of a waste old oxide battery by alkali leaching according to claim 1 or 2, characterized by, The concentration of the alkali in the basic leaching solution is 0.01-0.3 mol / L.

4. The method of claim 1 or 2, wherein the alkaline leaching recovery method of the spent oxide battery cathode material is characterized by, The temperature of the leaching reaction is 30-90 DEG C; the time of the leaching reaction is 1-10 h; the leaching reaction is carried out under stirring; the stirring speed is 100-500 r / min.

5. The method of claim 1 or 2, wherein the alkaline leaching recovery method of the spent oxide battery cathode material is characterized by, The soluble ferrous salt is selected from one or both of ferrous chloride and ferrous nitrate; the molar ratio of iron in the soluble ferrous salt to the waste oxide positive electrode material is 1:1-4:

1.

6. The method of claim 1 or 2, wherein the alkaline leaching recovery method of the spent oxide battery cathode material is characterized by, The waste oxide battery positive electrode material is added into the basic leaching solution according to the solid-liquid ratio control of 1-50 g / L.

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