RT Journal Article
T1 Desorption of rare earth elements (REEs) from schwertmannite under acid mine drainage (AMD) and AMD-seawater conditions
A1 Gutiérrez León, Joan
A1 Carrero Romero, Sergio
A1 Di Tommaso, Devis
A1 Toroz, Dimitrios
A1 Fernández Martínez, Alejandro
A1 Aguilar Tapia, Antonio
A1 Lozano, Alba
A1 Pérez López, Rafael
A1 Soler Matamala, Josep Maria
A1 Cama, J.
AB Schwertmannite as a sink for rare earth elements (REEs) in environments affected by acid mine drainage (AMD) plays a significant role in the fate of these elements. The conditions to precipitate schwertmannite (i.e., sulfate-rich water and pH between 2.5 and 3.5) are not suitable for this Fe-oxyhydroxysulfate (Fe8O8(OH)6SO4) to adsorb REEs. In estuaries where AMD-impacted rivers meet (e.g. the Odiel and the Tinto rivers in the Ría de Huelva estuary in SW Spain), AMD mixes with seawater raising the pH between 4.5 and 8, thereby enabling REE adsorption on schwertmannite at circumneutral pH. However, the estuarine tidal dynamics exposes REE-enriched schwertmannite to more acidic water, inducing REE desorption, which has yet to be studied. In the present work, batch experiments were performed to study the REE desorption from a REE-enriched schwertmannite within the pH range 4.5–7 in the presence of sulfate at room temperature. Solution-chemistry data were used to obtain the REE desorption surface constants from different surface complexation. Desorption of a Lu-enriched schwertmannite at different pH was investigated with High Energy X-Ray Diffraction (HEXD) and Extended X-ray Adsorption Fine Structure (EXAFS) to characterize the changes in the surface complexes during desorption. The results indicate that (1) REEs desorb from schwertmannite at pH < 6 and desorption is pH dependent, (2) desorption of light REEs is higher than that of heavy REEs, (3) REE sorption onto schwertmannite surface is not a totally reversible reaction, and that (4) both monodentate and bidentate surface complexes are involved in the Lu-desorption reaction. These observations indicate that (1) REE-enriched schwertmannite remains stable in the areas of the estuary nearer the sea and that (2) tidal fluctuations displace schwertmannite colloids towards areas that are more affected by AMD, inducing REE desorption from schwertmannite.
PB Elsevier
SN 0009-2541
SN 1872-6836 (electrónico)
YR 2024
FD 2024-12
LK https://hdl.handle.net/10272/24939
UL https://hdl.handle.net/10272/24939
LA eng
NO Gutiérrez-León, J., Carrero, S., Di Tommaso, D., Toroz, D., Fernandez-Martinez, A., Aguilar, A., Lozano, A., Pérez-López, R., Soler, J. M., & Cama, J. (2025). Desorption of rare earth elements (REEs) from schwertmannite under acid mine drainage (AMD) and AMD-seawater conditions. In Chemical Geology (Vol. 674, p. 122588). Elsevier BV. https://doi.org/10.1016/j.chemgeo.2024.122588
NO This work has been funded by the CGL2017–82331-R, PID2020- 119196RB-C21, PID2020-119196RB-C22 and PID2023-153280OA-I00 projects (Spanish Ministry of Economy and Competitiveness), with contribution of FEDER funds, and by the 2021SGR00308 project funded by the Catalan Government. IDAEA-CSIC is a Severo Ochoa Center of Research Excellence (Spanish Ministry of Science and Innovation, Project CEX2018–000794-S). S. Carrero also thanks to Ramon y Cajal Program (RYC2023–04529-I). We would like to acknowledge the technical assistance of N. Moreno, J. Belles, R. Batrolí and M. Cabañas (IDAEA-CSIC). We also would like to thank the ESRF for beamtime allocation at BM30 and ID22, and their respective reviewing teams (proposals EV-438 and EV-488). We also thank the editor (Dr. Karen H. Johannesson) and three anonymous reviewers for their constructive comments that helped us to improve the quality of the manuscript.
DS Repositorio Institucional de la Universidad de Huelva
RD 13 jul 2026