METHOD FOR SEPARATING AND RECOVERING VALUABLE METALS FROM WASTE TERNARY LITHIUM BATTERIES

Abstract

The present disclosure belongs to the technical field of lithium battery recycling, and discloses a method for separating and recovering valuable metals from waste ternary lithium batteries. The method includes the following steps: adding a persulfate to a waste ternary lithium battery powder, and conducting oxidative acid leaching to obtain a leaching liquor and a leaching residue; adding an alkali to the leaching liquor to allow a precipitation reaction; adding a sulfide salt to allow a reaction; adjusting a pH to allow a precipitation reaction to obtain a nickel hydroxide precipitate and a liquid phase A; adding a carbonate to the liquid phase A to allow a reaction, and conducting solid-liquid separation (SLS) to obtain lithium carbonate; and subjecting the leaching residue to calcination, adding a chlorate, heating a resulting mixture, and conducting SLS to obtain manganese dioxide.

Claims

1. A method for separating and recovering valuable metals from waste ternary lithium batteries, comprising the following steps: (1) adding a persulfate and a first acid to a waste ternary lithium battery powder for oxidative acid leaching, and conducting solid-liquid separation to obtain a leaching liquor and a leaching residue; (2) adding an alkali to the leaching liquor to allow a first precipitation reaction, and conducting solid-liquid separation to obtain a first liquid phase; adding a sulfide salt to allow a second precipitation reaction, and conducting solid-liquid separation to obtain a second liquid phase; and adjusting a pH of the second liquid phase to allow a third precipitation reaction, and conducting solid-liquid separation to obtain a nickel hydroxide precipitate and a liquid phase A; (3) adding a carbonate to the liquid phase A to allow a precipitation reaction, and conducting solid-liquid separation and collecting a solid phase to obtain lithium carbonate; and (4) subjecting the leaching residue obtained in step (1) to calcination, then adding a second acid and a chlorate, heating a resulting mixture, and conducting solid-liquid separation to obtain a solid phase and a liquid phase, wherein the solid phase is manganese dioxide and the liquid phase is a cobalt solution.

2. The method for separating and recovering valuable metals from waste ternary lithium batteries according to claim 1, wherein in step (1), the oxidative acid leaching is conducted at a temperature of 80° C. to 120° C. and a pH of 0.5 to 1.0.

3. The method for separating and recovering valuable metals from waste ternary lithium batteries according to claim 1, wherein in step (1), the persulfate is at least one selected from the group consisting of sodium persulfate, potassium persulfate, and ammonium persulfate.

4. The method for separating and recovering valuable metals from waste ternary lithium batteries according to claim 1, wherein in step (2), the alkali is one or two selected from the group consisting of sodium hydroxide and potassium hydroxide.

5. The method for separating and recovering valuable metals from waste ternary lithium batteries according to claim 1, wherein in step (2), the sulfide salt is one or two selected from the group consisting of sodium sulfide and potassium sulfide.

6. The method for separating and recovering valuable metals from waste ternary lithium batteries according to claim 1, wherein in step (2), the pH is adjusted to 9.5 to 10.0.

7. The method for separating and recovering valuable metals from waste ternary lithium batteries according to claim 1, wherein in step (3), the carbonate is one or two selected from the group consisting of sodium carbonate and potassium carbonate.

8. The method for separating and recovering valuable metals from waste ternary lithium batteries according to claim 1, wherein in step (1), the first acid is one selected from the group consisting of sulfuric acid and hydrochloric acid; and in step (4), the second acid is one selected from the group consisting of sulfuric acid and hydrochloric acid.

9. The method for separating and recovering valuable metals from waste ternary lithium batteries according to claim 1, wherein in step (4), the chlorate is one or two selected from the group consisting of sodium chlorate and potassium chlorate.

10. The method for separating and recovering valuable metals from waste ternary lithium batteries according to claim 1, wherein in step (4), the liquid phase is used to prepare cobalt hydroxide.

Description

BRIEF DESCRIPTION OF DRAWINGS

[0052] The sole FIGURE is a schematic diagram of the process flow of the present disclosure.

DETAILED DESCRIPTION

[0053] The concepts and technical effects of the present disclosure are clearly and completely described below in conjunction with examples, so as to allow the objectives, features and effects of the present disclosure to be fully understood. Apparently, the described examples are merely some rather than all of the examples of the present disclosure. All other examples obtained by those skilled in the art based on the examples of the present disclosure without creative efforts should fall within the protection scope of the present disclosure.

Example 1

[0054] A method for separating and recovering valuable metals from waste ternary lithium batteries was provided in this example, including the following steps:

[0055] 100 g of a waste ternary lithium battery powder was collected, which had the following metal contents: nickel: 15.37%, cobalt: 11.26%, manganese: 9.42%, lithium: 4.23%, iron: 0.96%, aluminum: 1.56%, and copper: 1.51%. Valuable metals were separated and recovered through the following steps:

[0056] (1) The 100 g of waste ternary lithium battery powder was subjected to oxidative acid leaching in a mixed system of 0.5 L of sulfuric acid and 145 g of SPS, and then SLS was conducted to obtain a leaching liquor and a leaching residue, where the oxidative acid leaching was conducted for 6 h at a pH of 0.5 to 1.0 and a temperature of 90° C.

[0057] (2) A pH of the leaching liquor was adjusted to 5.0 to 5.5 with sodium hydroxide for hydrolytic precipitation (to remove iron and aluminum ions); after the hydrolytic precipitation was completed, 2.0 g of sodium sulfide was added for deep removal of copper; and a pH of a liquid obtained after the deep removal of copper was adjusted to 9.5 to 10.0 for complete precipitation of nickel ions to obtain 24.13 g of nickel hydroxide and a liquid phase A.

[0058] (3) 35 g of sodium carbonate was added to the liquid phase A for precipitation, and then SLS was conducted to obtain 21.76 g of lithium carbonate.

[0059] (4) The leaching residue obtained in step (1) was dried and weighed 67.43 g; then the leaching residue was subjected to calcination at 800° C. in an air atmosphere to obtain 27.93 g of a calcination residue; 1.2 L of 0.2 mol/L sulfuric acid was added to the calcination residue for dissolution, then 4 g of sodium chlorate was added, and a resulting mixture was subjected to a reaction at 100° C. for 4 h; SLS was conducted to obtain 14.9 g of active manganese dioxide and a liquid; and a pH of the liquid was adjusted to 9.0 to 9.5 for complete precipitation of cobalt ions to obtain 17.83 g of cobalt hydroxide.

[0060] Without considering the impurities in each product, a yield was calculated, and calculation results were as follows: nickel: 99.41%, cobalt: 100.41% (which may be partially oxidized), manganese: 99.99% (which may include a small amount of impurities), and lithium: 96.65%.

Example 2

[0061] A method for separating and recovering valuable metals from waste ternary lithium batteries was provided in this example, including the following steps:

[0062] 100 g of a waste ternary lithium battery powder was collected, which had the following metal contents: nickel: 19.73%, cobalt: 12.38%, manganese: 13.66%, lithium: 4.34%, iron: 0.98%, aluminum: 1.72%, and copper: 1.49%. Valuable metals were separated and recovered through the following steps:

[0063] (1) The 100 g waste ternary lithium battery powder was subjected to oxidative acid leaching in a mixed system of 0.4 L of sulfuric acid and 280 g of SPS, and then SLS was conducted to obtain a leaching liquor and a leaching residue, where the oxidative acid leaching was conducted for 4 h at a pH of 0.5 to 1.0 and a temperature of 100° C.

[0064] (2) A pH of the leaching liquor was adjusted to 5.0 to 5.5 with sodium hydroxide for hydrolytic precipitation (to remove iron and aluminum ions); after the hydrolytic precipitation was completed, 2.0 g of sodium sulfide was added for deep removal of copper; and a pH of a liquid obtained after the deep removal of copper was adjusted to 9.5 to 10.0 for complete precipitation of nickel ions to obtain 30.97 g of nickel hydroxide and a liquid phase A.

[0065] (3) 35 g of sodium carbonate was added to the liquid phase A for precipitation, and then SLS was conducted to obtain 22.06 g of lithium carbonate.

[0066] (4) The leaching residue obtained in step (1) was dried and weighed 61.02 g; then the leaching residue was subjected to calcination at 900° C. in an air atmosphere to obtain 35.40 g of a calcination residue; 0.25 L of 1 mol/L sulfuric acid was added to the calcination residue for dissolution, then 5.5 g of sodium chlorate was added, and a resulting mixture was subjected to a reaction at 90° C. for 2 h; SLS was conducted to obtain 21.45 g of active manganese dioxide and a liquid; and a pH of the liquid was adjusted to 9.0 to 9.5 for complete precipitation of cobalt ions to obtain 19.47 g of cobalt hydroxide.

[0067] Without considering the impurities in each product, a yield was calculated, and calculation results were as follows: nickel: 99.39%, cobalt: 99.73%, manganese: 99.27%, and lithium: 95.49%.

Example 3

[0068] A method for separating and recovering valuable metals from waste ternary lithium batteries was provided in this example, including the following steps:

[0069] 100 g of a waste ternary lithium battery powder was collected, which had the following metal contents: nickel: 18.24%, cobalt: 13.22%, manganese: 12.33%, lithium: 4.55%, iron: 0.83%, aluminum: 1.32%, and copper: 1.21%. Valuable metals were separated and recovered through the following steps:

[0070] (1) The 100 g waste ternary lithium battery powder was subjected to oxidative acid leaching in a mixed system of 0.3 L of sulfuric acid and 350 g of SPS, and then SLS was conducted to obtain a leaching liquor and a leaching residue, where the oxidative acid leaching was conducted for 3 h at a pH of 0.5 to 1.0 and a temperature of 80° C.

[0071] (2) A pH of the leaching liquor was adjusted to 5.0 to 5.5 with sodium hydroxide for hydrolytic precipitation (to remove iron and aluminum ions); after the hydrolytic precipitation was completed, 1.5 g of sodium sulfide was added for deep removal of copper; and a pH of a liquid obtained after the deep removal of copper was adjusted to 9.5 to 10.0 for complete precipitation of nickel ions to obtain 28.61 g of nickel hydroxide and a liquid phase A.

[0072] (3) 38 g of sodium carbonate was added to the liquid phase A for precipitation, and then SLS was conducted to obtain 22.33 g of lithium carbonate.

[0073] (4) The leaching residue obtained in step (1) was dried and weighed 64.01 g; then the leaching residue was subjected to calcination at 600° C. in an air atmosphere to obtain 34.53 g of a calcination residue; 0.8 L of 0.5 mol/L sulfuric acid was added to the calcination residue for dissolution, then 5 g of sodium chlorate was added, and a resulting mixture was subjected to a reaction at 80° C. for 1 h; SLS was conducted to obtain 19.39 g of active manganese dioxide and a liquid; and a pH of the liquid was adjusted to 9.0 to 9.5 for complete precipitation of cobalt ions to obtain 20.71 g of cobalt hydroxide.

[0074] Without considering the impurities in each product, a yield was calculated, and calculation results were as follows: nickel: 99.32%, cobalt: 99.42% (which may be partially oxidized), manganese: 99.42%, and lithium: 92.20%.

[0075] The sole FIGURE is a schematic diagram of the process flow of the present disclosure. It can be seen from the sole FIGURE that, in the present disclosure, the waste battery powder is first subjected to oxidative acid leaching to obtain a leaching liquor and a leaching residue; and then the leaching liquor and the leaching residue are treated separately to finally obtain nickel hydroxide, lithium carbonate, manganese dioxide, and cobalt hydroxide.

[0076] The above examples are preferred implementations of the present disclosure, and the implementations of the present disclosure are not limited by the above examples. Any change, modification, and simplification made without departing from the spiritual essence and principle of the present disclosure should be equivalent replacements, and all are included in the protection scope of the present disclosure.