Hostname: page-component-78c5997874-j824f Total loading time: 0 Render date: 2024-11-19T06:24:30.552Z Has data issue: false hasContentIssue false
  • English
  • Français

Green rust as a precursor for magnetite: an in situ synchrotron based study

Published online by Cambridge University Press:  05 July 2018

A. Sumoondur ,
S. Shaw ,
I. Ahmed  and
L. G. Benning
A. Sumoondur*
Affiliation:
Earth and Biosphere Institute, School of Earth and Environment, University of Leeds, Leeds, LS2 9JT, UK
S. Shaw
Affiliation:
Earth and Biosphere Institute, School of Earth and Environment, University of Leeds, Leeds, LS2 9JT, UK
I. Ahmed
Affiliation:
Earth and Biosphere Institute, School of Earth and Environment, University of Leeds, Leeds, LS2 9JT, UK
L. G. Benning
Affiliation:
Earth and Biosphere Institute, School of Earth and Environment, University of Leeds, Leeds, LS2 9JT, UK
*
*E-mail: [email protected]
Get access Rights & Permissions [Opens in a new window]

Abstract

In this study, direct evidence for the formation of magnetite via a green rust intermediate is reported. The Fe(II) induced transformation of ferrihydrite, was quantified in situ and under O2-free conditions using synchrotron-based time-resolved energy dispersive X-ray diffraction. At pH 9 and Fe(II)/Fe(III) ratios of 0.5 and 1, rapid growth (6 min) of sulphate green rust and its subsequent transformation to magnetite was observed. Electron microscopy confirmed these results, showing the initial rapid formation of hexagonal sulphate green rust particles, followed by the corrosion of the green rust as magnetite growth occurred, indicating that the reaction proceeds via a dissolution-reprecipitation mechanism. At pH 7 and Fe(II)/Fe(III) ratio of 0.5, sulphate green rust was the stable phase, with no transformation to magnetite.

Keywords

magnetitegreen rustnanoparticulatesynchrotrondiffraction
Type
Research Article
Information
Mineralogical Magazine , Volume 72 , Issue 1 , February 2008 , pp. 201 - 204
Copyright
Copyright © The Mineralogical Society of Great Britain and Ireland 2008

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

Bernal, J.D., Dasgupta, D.R. and Mackay, A.L. (1959) The oxides and hydroxides of iron and their structural inter-relationships. Clay Minerals Bulletin, 4, 15–30.Google Scholar
Clark, S.M. (1996) A new energy-dispersive powder diffraction facility at the SRS. Nuclear Instruments and Methods in Physics Research, A381, 161–168.Google Scholar
Cornell, R.M. and Schwertmann, U. (2003) The Iron Oxides: Structure, Properties, Reactions, Occurrences and Uses. Weinhem, Wiley-VCH. 664 pp.CrossRefGoogle Scholar
Hansel, CM., Benner, S.G., Neiss, J., Dohnalkova, A., Kukkadapu, R.K. and Fendorf, S. (2003) Secondary mineralization pathways induced by dissimilatory iron reduction of ferrihydrite under advective flow. Geochimica et Cosmochimica Ada, 67, 2977–2992.CrossRefGoogle Scholar
Kukkadapu, R.K., Zachara, J.M., Fredrickson, J.K, Kennedy, D.W., Dohnalkova, A.C. and McCready, D.E. (2005) Ferrous hydroxy carbonate is a stable transformation product of biogenic magnetite. American Mineralogist, 90, 510–515.CrossRefGoogle Scholar
Lovley, D.R. (1991) Dissimilatory Fe(III) and Mn(IV) reduction. Microbiology and Molecular Biology Reviews, 55, 259–287.Google ScholarPubMed
Mazeina, L., Navrotsky, A. and Dyar, D. (2008) Enthalpy of formation of sulfate green rusts. Geochimica et Cosmochimica Ada, 72, 1143–1153.CrossRefGoogle Scholar
Satapanajaru, T., Shea, P.J., Comfort, S.D. and Roh, Y. (2003) Green rust and iron oxide formation influences metolachlor dechlorination during zer-ovalent iron treatment. Environmental Science and Technology, 37, 5219–5227.CrossRefGoogle ScholarPubMed
Simon, L., Francois, M., Refait, P., Renaudin, G., Lelaurain, M. and Genin, J.-M.R. (2003) Structure of the Fe(II-III) layered double hydroxysulphate green rust two from rietveld analysis. Solid State Sciences, 5, 327–334.CrossRefGoogle Scholar
Weber, K.A., Achenbach, L.A. and Coates, J.D. (2006) Microorganisms pumping iron: Anaerobic microbial iron oxidation and reduction. Nature Reviews: Microbiology, 4, 752–764.Google ScholarPubMed
Zegeye, A., Ruby, C. and Jorand, F. (2007) Kinetic and thermodynamic analysis during dissimilatory a-FeOOH reduction: Formation of green rust 1 and magnetite. Geomicrobiology Journal, 24, 51–64.CrossRefGoogle Scholar