| CPC H01M 10/54 (2013.01) [C22B 3/08 (2013.01); C22B 3/22 (2013.01); C22B 7/007 (2013.01); C22B 23/0461 (2013.01); C22B 26/12 (2013.01); C22B 47/00 (2013.01)] | 7 Claims |

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1. A method for comprehensive recovery of cobalt, nickel, manganese and lithium elements from ternary battery wastes, comprising the following steps:
a, disassembling waste ternary batteries to obtain waste ternary battery powder, and leaching the waste ternary battery powder with an acid for removing copper, iron and aluminum to obtain an impurity-removed solution;
b, adjusting a pH of the impurity-removed solution to 5.5-6.5 with sodium hydroxide, precipitating a mixture of cobalt hydroxide and nickel hydroxide, filtering and washing to obtain a filter cake and a filtrate, and treating the filter cake and the filtrate respectively;
c, dissolving the filter cake, which is a mixture of cobalt hydroxide and nickel hydroxide, with sulfuric acid, then, adjusting the pH to 5.0-6.0, adding fluoride into the dissolving solution to remove calcium and magnesium ions, filtering and washing to obtain a filtrate, allowing the filtrate to enter into a first impurity extraction procedure, removing impurities deeply, allowing raffinate to enter into a second extraction procedure, performing the second extraction procedure cobalt ion full extraction and full back-extraction to obtain a high-concentration pure solution of cobalt sulfate, evaporating and crystallizing the solution to obtain a battery-grade cobalt sulfate product, and allowing a nickel sulfate solution as the raffinate to enter into a third impurity extraction procedure;
d, obtaining pure nickel sulfate liquid as the raffinate after the third impurity extraction procedure, adjusting the pH to 6-10 with sodium hydroxide, precipitating nickel hydroxide, reversely washing the precipitates with pure water for 2-4 times to obtain a filter cake which is battery-grade nickel hydroxide, and treating the filtrate and the washing solution by a wastewater station for recycling;
e, adding sodium sulfide into the filtrate and the washing solution obtained in step b to remove the residual cobalt and nickel ions, filtering and washing to obtain a filter cake which is a mixture of cobalt sulfide and nickel sulfide, returning to the acid dissolution procedure, and allowing the filtrate and the washing solution to enter into the manganese precipitation procedure; and
in step e of adding sodium sulfide, solid sodium sulfide is added by 2.0-5.0 times of the total amount of cobalt and nickel in the filtrate and the washing solution obtained in step b; and the reaction lasts for 30-60 minutes to recover the residual cobalt and nickel ions;
f, adjusting the pH of the filtrate and the washing solution obtained in step e to 8-11 with sodium hydroxide, to precipitate manganese ions, filtering and washing to obtain a manganese hydroxide filter cake and a lithium-containing filtrate and washing solution;
g, evaporating and crystallizing sodium sulfate from the lithium-containing filtrate and washing solution to obtain a concentrated lithium solution, precipitating lithium carbonate with sodium carbonate, filtering and washing to obtain a lithium carbonate filter cake and a lithium precipitation mother liquor.
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