Separation of Lithium from Aluminum-Containing Clay Mineral Leachate Solution Using Energy-Efficient Membrane Solvent...

Area of Science:

• Materials Science
• Chemical Engineering
• Hydrometallurgy

Background:

• Lithium (Li) recovery from clay minerals is essential for clean energy technologies.
• Existing methods for Li separation from aluminum (Al) can be inefficient.
• Development of advanced extraction techniques is needed for high-purity Li.

Purpose of the Study:

• To investigate a novel membrane solvent extraction (MSX) process for Li recovery.
• To selectively separate Li from Al using di-(2-ethylhexyl)phosphoric acid (DEHPA).
• To evaluate the efficiency and purity of Li obtained via the MSX process.

Main Methods:

• Selective extraction of Li from clay mineral leachate using aluminum hydroxide sorbents.
• Dissolution of lithium aluminum double hydroxide sulfate (LDH sulfate) in dilute H2SO4.
• Membrane solvent extraction (MSX) immobilizing DEHPA in microporous membranes for continuous Al removal.

Main Results:

• Optimized MSX process conditions: pH 3, 2 mol/L H2SO4 strip solution, 30% v/v DEHPA in Isopar-L.
• Achieved a Li yield of approximately 92%.
• Obtained Li purity of ⩾ 94%.

Conclusions:

• The MSX process is a highly efficient and selective method for Li recovery and separation from clay minerals.
• This innovative technology offers a time- and energy-efficient approach for producing high-purity Li.
• The developed MSX process holds significant potential for applications in Li-ion batteries and other clean energy technologies.