Method for lithium recovery by extraction-stripping separation and purification
AssigneesInstitute of Process Engineering, Chinese Academy of Sciences, Shanghai Yiding New Material Technology Co., Ltd
InventorsTao Qi, Zhaowu Zhu, Jian Zhang, Daoyong Lin
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Abstract
The present disclosure relates to a method for lithium recovery by extraction-stripping separation and purification, including: (1) performing an extraction on a lithium-containing solution using an extraction system including a composite extractant at a pH in a range of 10-13 and separating to obtain a lithium-loaded organic phase; (2) subjecting the lithium-loaded organic phase obtained in step (1) to a gas-liquid-liquid three-phase stripping to obtain a lithium-loaded stripping solution; and (3) subjecting the stripping solution obtained in step (2) to a thermal treatment and separating to obtain a lithium product and a separated mother liquor.
Claims16
A method for lithium recovery by extraction-stripping separation and purification, comprising:
- (1) performing an extraction on a lithium-containing solution using an extraction system comprising a composite extractant at a pH in a range of 10-13 and separating to obtain a lithium-loaded organic phase;
- (2) subjecting the lithium-loaded organic phase obtained in step (1) to a gas-liquid-liquid three-phase stripping to obtain a lithium-loaded stripping solution;
- and
- (3) subjecting the stripping solution obtained in step (2) to a thermal treatment and separating to obtain a lithium product and a separated mother liquor;
- wherein the gas-liquid-liquid three-phase comprises a gas phase, a first liquid phase, and a second liquid phrase;
- in step (2), the gas-liquid-liquid three-phase stripping is controlled at a pH in a range of 6-9;
- and
- in step (2), the gas phase comprises an acid gas, and the acid gas is introduced continuously;
- wherein in step (2), the gas-liquid-liquid three-phase stripping is operated in a multi-stage continuous countercurrent mode;
- an equipment for the gas-liquid-liquid three-phase stripping comprises any one of a continuous mixing clarification tank, an extraction tower or a centrifugal extractor;
- a stage number of the gas-liquid-liquid three-phase stripping is adjustable between 1 and 10;
- and
- in step (2), a concentration of lithium in the stripping solution is more than 5 g/L.
Dependencies are inferred from the claim text.