Method for extracting lithium from slag produced by fire recovery lithium battery

Abstract

The invention relates to a method for extracting lithium in slag produced through recycling of a lithium battery by a pyrogenic process, and belongs to the technical field of an energy material. The invention provides the method for extracting the lithium in the slag produced through recycling of the lithium battery by the pyrogenic process. According to the method, leaching by hydrochloric acid is performed, vacuum drying is performed under an appropriate temperature condition to remove aluminum, the aluminum-removal slag is leached, a large amount of calcium chloride is precipitated by adding lithium sulfate into the leaching liquid, univalent lithium and divalent ions in the solution are separated by a nano-filtration membrane, the univalent lithium solution is concentrated and can be processed to form a lithium salt product, the divalent-ion solution is alkalized to remove impurity and then is returned to a front segment for leaching, and the alkalization slag can be used for extracting valuable metal elements of nickel, cobalt and manganese. By the method, the lithium element can be extracted from the slag with relatively high content of aluminum and calcium, meanwhile, the valuable metal elements such as nickel, cobalt and manganese in the slag also can be extracted, maximum economic value of the slag is achieved, moreover, the process is simple in condition and high in operability, furnace burden can be greatly processed, and the process is easy to achieve in industry.

Description

technical field [0001] The invention relates to a method for extracting lithium from slag produced by recovering lithium batteries by fire method, and belongs to the technical field of energy materials. Background technique [0002] In recent years, the three major fields of consumer electronics, electric vehicles and grid energy storage have developed rapidly, which has greatly promoted the development of lithium-ion batteries. With the increasing number of lithium-ion batteries on the market and the gradual completion of the life cycle of lithium-ion batteries on the market, the number of waste lithium-ion batteries will increase, and the recycling of waste lithium-ion batteries is imperative. The recycling of used lithium-ion batteries can not only avoid environmental pollution, but also alleviate the contradiction between resource demand and supply, and alleviate concerns about lithium resources. [0003] Lithium-ion battery recycling technology can be divided into wet ...

AI Technical Summary

Problems solved by technology

The disadvantage of this process is that aluminum ions are precipitated by adjusting the pH value. Since the generated aluminum hydroxide is amorphous, it is difficult to filter, and a large amount of water needs to be added, resulting in a very low lithium concentration in the resulting solution, which requires a higher cost. Concentration cost of

[0008] To sum up, the slag produced by the fire recycling process of waste lithium-ion batteries has complex components, but contains high-grade lithium resources and a certain amount of nickel-cobalt-manganese, and has high economic added value.

However, the existing slag treatment technologies either do not recover the lithium resources in them, or the process is complicated, and the removal cost of aluminum ions is high, and they cannot maximize the benefits of slag at low cost.

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