A Cage Structural Hollow-Mesoporous Microreactor Confining Extractant for Lithium Recovery from Salt-Lake Brine

Area of Science:

• Materials Science
• Chemical Engineering
• Sustainable Energy

Background:

• Efficient lithium extraction is crucial for global decarbonization and electrified industries.
• Current solvent extraction methods face challenges with extractant dissolution and low efficiency.

Purpose of the Study:

• To develop a stable hollow-mesoporous microreactor for enhanced lithium separation from salt-lake brine.
• To overcome limitations of conventional lithium extraction technologies.

Main Methods:

• Fabrication of a cage-structured hollow-mesoporous microreactor.
• Confinement of the lithium extractant, Na[FeCl4·2TBP], within the microreactor's hollow cavity.
• Testing separation performance in simulated salt-lake brine, including high Mg/Li ratios.

Main Results:

• The microreactor prevented extractant dissolution and compartmentalized it into stable droplets.
• Achieved high Li+ separation performance with a Mg/Li mass ratio up to 100:1.
• Demonstrated high cyclic stability, adsorption capacity (34.6 mg/g), and Li+/Mg2+ selectivity (nearly 1000, ~6x higher than conventional methods).

Conclusions:

• The microreactor design significantly enhances lithium separation efficiency and selectivity.
• The confinement effect and mesopore-facilitated ion transport contribute to improved performance.
• This approach offers a novel strategy for efficient lithium recovery from aqueous solutions.