Hostname: page-component-cd9895bd7-lnqnp Total loading time: 0 Render date: 2024-12-26T15:10:21.788Z Has data issue: false hasContentIssue false
  • English
  • Français

Effect of Solution Conditions on the Proportion and Morphology of Goethite Formed from Ferrihydrite

Published online by Cambridge University Press:  02 April 2024

R. M. Cornell  and
R. Giovanoli
R. M. Cornell
Affiliation:
Institute of Inorganic Chemistry, University of Berne, Freiestrasse 3, CH-3000 Berne 9, Switzerland
R. Giovanoli
Affiliation:
Laboratory of Electron Microscopy, University of Berne, Freiestrasse 3, CH-3000 Berne 9, Switzerland
Rights & Permissions [Opens in a new window]

Abstract

Core share and HTML view are not available for this content. However, as you have access to this content, a full PDF is available via the ‘Save PDF’ action button.

In alkaline media and at 70°C dilute suspensions of ferrihydrite transformed to goethite between pH 11.2 and 14 and to a mixture of goethite and hematite above and below this pH range. Increasing the temperature of the transformation or the concentration of the suspension reduced the pH range in which goethite alone formed. The morphology of goethite was chiefly a function of the pH of the system. Acicular crystals formed at all pHs and exclusively above pH 12.2. Epitaxial twinned crystals predominated at pHs below 11, and twins free from hematite formed at higher pHs. Increasing the suspension concentration, ionic strength, or temperature extended the pH range over which twinned crystals formed. Electron micrographs showed that twins formed mainly during the initial stage of the transformation, whereas acicular crystals formed over a longer period. Thus, the twins appeared to nucleate in the ferrihydrite; nucleation of acicular particles took place in solution.

Keywords

FerrihydriteGoethiteHydroxylIronMorphologyTransmission electron microscopy
Type
Research Article
Information
Clays and Clay Minerals , Volume 33 , Issue 5 , October 1985 , pp. 424 - 432
Copyright
Copyright © 1985, The Clay Minerals Society

References

Atkinson, R. J., Posner, A. M. and Quirk, J. P., 1968 Crystal nucleation in Fe(III) solutions and hydroxide gels J. Inorg. Nucl. Chem. 30 2371–2381.CrossRefGoogle Scholar
Cornell, R. M., Mann, S. and Skamulis, A. J., 1983 A high-resolution electron microscopy examination of domain boundaries in crystals of synthetic goethite J. Chem. Soc. Faraday Trans. I 79 2679–2684.CrossRefGoogle Scholar
Cornell, R. M. and Schwertmann, U., 1979 Influence of organic anions on the crystallization of ferrihydrite Clays & Clay Minerals 27 402–410.CrossRefGoogle Scholar
Cotton, F. A. and Wilkinson, G., 1980 Advanced Inorganic Chemistry 4th ed. New York Wiley.Google Scholar
Feitknecht, W. and Michaelis, W., 1962 Über die Hydrolyse von Eisen(III)-perchlorat-Lösungen Helv. Chim. Acta 26 212–224.CrossRefGoogle Scholar
Fischer, W. R. and Schwertmann, U., 1975 The formation of hematite from amorphous iron(III) hydroxide Clays & Clay Minerals 23 33–37.CrossRefGoogle Scholar
Fordham, A. W., Merry, R. H. and Norrish, K., 1984 Occurrence of microcrystalline goethite in an unusual fibrous form Geoderma 34 135–148.CrossRefGoogle Scholar
Johnson, J. H. and Lewis, D. G., 1983 A detailed study of the transformation of ferrihydrite to hematite in an aqueous medium at 92°C Geochim. Cosmochim. Acta 47 1823–1831.CrossRefGoogle Scholar
Lewis, D. D. and Schwertmann, U., 1980 The effect of [OH−] on the goethite produced from ferrihydrite under alkaline conditions J. Colloid Interface Sei. 78 543–553.CrossRefGoogle Scholar
Murad, E., 1979 Mössbauer and X-ray data on β-FeOOH (akaganeite) Clay Miner. 14 273–283.CrossRefGoogle Scholar
Nakai, M. and Yoshinaga, N., 1980 Fibrous goethite in some soils from Japan and Scotland Geoderma 24 143–158.CrossRefGoogle Scholar
Schwertmann, U., 1964 Differenzierung der Eisenoxide des Bodens durch Extraction mit einer Ammonium Oxalat-Lösung Z. Pflanzenernähr. Düng. Bodenkd. 105 194–202.CrossRefGoogle Scholar
Schwertmann, U., 1984 The effect of pedogenic environments on iron oxide minerals Advances in Soil Sei. 1 172–200.Google Scholar
Schwertmann, U. and Fischer, W. R., 1966 Zur Bildung von α-FeOOH und α-Fe2O3 aus amorphem Eisen(III) hydroxide Z. Anorg. Allg. Chem. 346 137–142.CrossRefGoogle Scholar
Schwertmann, U. and Murad, E., 1983 The effect of pH on the formation of goethite and hematite from ferrihydrite Clays & Clay Minerals 31 277–284.CrossRefGoogle Scholar
Torrent, J. and Guzman, R., 1982 Crystallization of Fe(III)-oxides from ferrihydrite in salt solutions: osmotic and specific ion effects Clay Miner. 17 463–469.CrossRefGoogle Scholar