Work

Recovery of rare earth elements from low-grade coal fly ash using a recyclable protein biosorbent

Year: 2024

Type: article

Abstract: Rare earth elements (REEs), including those in the lanthanide series, are crucial components essential for clean energy transitions, but they originate from geographically limited regions. Exploiting new and diverse supply sources is vital to facilitating a clean energy future. Hence, we explored the recovery of REEs from coal fly ash (FA), a complex, low-grade industrial feedstock that is currently underutilized (leachate concentrations of REEs in FA are < 0.003 mol%). Herein, we demonstrated the thermo-responsive genetically encoded REE-selective elastin-like polypeptides (RELPs) as a recyclable bioengineered protein adsorbent for the selective retrieval of REEs from coal fly ash over multiple cycles. The results showed that RELPs could be efficiently separated using temperature cycling and reused with high stability, as they retained ∼95% of their initial REE binding capacity even after four cycles. Moreover, RELPs selectively recovered high-purity REEs from the simulated solution containing one representative REE in the range of 0.0001-0.005 mol%, resulting in up to a 100,000-fold increase in REE purity. This study offers a sustainable approach to diversifying REE supplies by recovering REEs from low-grade coal fly ash in industrial wastes and provides a scientific basis for the extraction of high-purity REEs for industrial purposes.

Source: Frontiers in Bioengineering and Biotechnology

DOI: 10.3389/fbioe.2024.1385845

Authors: Zohaib Hussain, Divya Dwivedi, Inchan Kwon

Institution: Gwangju Institute of Science and Technology

Language: English

Topic: Coal and Its By-products

Subfield: Geochemistry and Petrology

Field: Earth and Planetary Sciences

Domain: Physical Sciences

SDGs: Responsible consumption and production, Affordable and clean energy

Open Access status: gold

Estimated APC paid: $3,295