Selective and Efficient Biomacromolecular Extraction of Rare-Earth Elements using Lanmodulin.

Area of Science:

• Biochemistry
• Metalloprotein Chemistry
• Extractive Metallurgy

Background:

• Lanmodulin (LanM) is a novel protein exhibiting significant conformational changes upon binding rare-earth elements (REEs).
• Existing methods for REE extraction often lack selectivity and stability under harsh industrial conditions.

Purpose of the Study:

• To characterize the metal-binding properties and structural stability of Lanmodulin (LanM).
• To evaluate LanM's efficacy in selectively recovering REEs from complex industrial feedstocks.

Main Methods:

• Multiple physicochemical methods were employed to assess LanM's selectivity and stability.
• LanM's performance was tested using precombustion coal and electronic waste leachates.

Main Results:

• LanM demonstrated unparalleled selectivity for REEs over other metal ions, even under acidic conditions (pH ≈ 2.5) and high temperatures (up to 95 °C).
• Quantitative and selective REE recovery was achieved in a single aqueous step from diverse industrial sources, removing interfering ions like Mg, Ca, Zn, and Cu.
• LanM successfully extracted REEs from low-grade industrial feedstocks, including coal and electronic waste.

Conclusions:

• Lanmodulin (LanM) is the most selective macromolecule for REEs identified to date, surpassing synthetic chelators.
• LanM's robust stability and universal selectivity offer a promising bio-based solution for REE extraction in extractive metallurgy.
• This discovery paves the way for utilizing underutilized low-grade sources and developing sustainable f-element separation technologies.