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Transformation of ferrihydrite to hematite: an in situ investigation on the kinetics and mechanisms

Published online by Cambridge University Press:  05 July 2018

H. P. Vu ,
S. Shaw  and
L. G. Benning
H. P. Vu*
Affiliation:
School of Earth and Environment, University of Leeds, LS2 9JT, UK
S. Shaw
Affiliation:
School of Earth and Environment, University of Leeds, LS2 9JT, UK
L. G. Benning
Affiliation:
School of Earth and Environment, University of Leeds, LS2 9JT, UK
*
*E-mail: h.vu@see.leeds.ac.uk
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Abstract

The kinetics and mechanisms of the transformation of 2-line ferrihydrite (FH) to hematite (HM), in the presence of Pb at elevated temperatures and high pH condition, were elucidated using synchrotron-based, in situ energy dispersive X-ray diffraction (EDXRD). The time-resolved diffraction data indicated that HM crystallization occurred via a two-stage process. Based on the EDXRD data, combined with high-resolution electron microscopic images, an aqueous-aided 2D growth mechanism is proposed for both HM crystallization stages.

Type
Research Article
Information
Mineralogical Magazine , Volume 72 , Issue 1 , February 2008 , pp. 217 - 220
Copyright
Copyright © The Mineralogical Society of Great Britain and Ireland 2008

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