Mechanistic Understanding of Rare-earth Element (REE) Capture

REE capture graphic
REE capture by synthetic aluminosilicate MCM-22 from aqueous solution under ambient conditions.
Scientific Achievement

MCM-22 synthesis with varying Si:Al ratios is a model aluminosilicate for ytterbium (Yb) capture and serves as a synthetic clay mimic to obtain in-depth mechanistic understanding of the capture.

Significance and Impact

A correlation of rare-earth element (REE) capture and aluminum (Al) content in the material was observed. From experimental and computational investigations, it is postulated that the Al-bridged sites (Brønsted acid sites and siloxanes) play a key role in the REE capture by ionic interactions in aluminosilicate frameworks.

Research Details
  • Pure MCM-22 phase materials synthesized with varying Al content and their effect on the structure observed.
  • Kinetics, isotherm, pH-dependent studies, solid-state NMR experiments, and computational studies conducted to obtain molecular level picture of the REE capture.

Article Link: https://doi.org/10.1021/acsami.3c14560