RT Journal Article
T1 Sequential extraction and DXRD applicability to poorly crystalline Fe- and Al-phase characterization from an acid mine water passive remediation system
A1 Caraballo Monge, Manuel Antonio
A1 Rötting, Tobías S.
A1 Nieto Liñán, José Miguel
A1 Ayora, Carlos
AB Iron and Al precipitates play very important hydrochemical and environmental roles in aquatic environments affected by acid mine drainage. Despite their great importance, reliable characterization of these precipitates is problematic due to the high proportion of amorphous or poorly ordered mineral phases comprising these precipitates and because of their coexistence with intermediate to highly crystalline phases. To facilitate and improve the characterization of poorly ordered Fe and Al phases, a coupled differential X-ray diffraction (DXRD) and sequential extraction (SE) study was performed on a set of samples from an acid mine water passive treatment system. The results of these techniques indicate the presence of schwertmannite and goethite in the upper 5 cm of the passive treatment reactive material. Furthermore, a progressive decrease of the SO42- adsorbed to the schwertmannite surface is suggested by one of the SE steps. The presence of hydrobasaluminite and amorphous Al(OH)3 is suggested on the basis of SE and thermodynamic modeling analysis. These techniques also allow a quantitative estimation of the proportion of each mineral present. As a result, a complete study of the distribution of each mineral throughout the reactive material profile and the role of each phase in removing metals from the mine water can be obtained. This information is useful, not only to improve the reactive material design, but also to understand the natural processes taking place in aquatic systems affected by mining.
PB Mineralogical Society of America
SN 0003-004X
SN 1945-3027 (electrónico)
YR 2009
FD 2009
LK https://hdl.handle.net/10272/23188
UL https://hdl.handle.net/10272/23188
LA eng
NO Caraballo, M. A., Rotting, T. S., Nieto, J. M., & Ayora, C. (2009). Sequential extraction and DXRD applicability to poorly crystalline Fe- and Al-phase characterization from an acid mine water passive remediation system. In American Mineralogist (Vol. 94, Issue 7, pp. 1029–1038). Mineralogical Society of America. https://doi.org/10.2138/am.2009.3137
NO This study was funded by the Spanish Government projects REN-2003-09590-C04, CTM2006-28151-E/TECNO and CTM2007-66724-C02.  M.A.C. was financially supported by the Spanish Government with PhD fellowship. We are grateful to Patricia Acero from University of Zaragoza for the fruitful discussions and help. We would also like to thank the analytical assistance of Rafael Carrasco and Mari Paz Martín from the Central Research Services of the University of Huelva.
DS Repositorio Institucional de la Universidad de Huelva
RD 31 may 2026