THE INFLUENCE OF GOLD ON THE CRYSTALLIZAT ION OF IRON OXI-HYDROXIDES

Authors
GREFFIE C BENEDETTI M PARRON C HIEMSTRA T
Citation
C. Greffie et al., THE INFLUENCE OF GOLD ON THE CRYSTALLIZAT ION OF IRON OXI-HYDROXIDES, Comptes rendus de l'Academie des sciences. Serie II. Sciences de la terre et des planetes, 322(3), 1996, pp. 197-204
Citations number
19
Categorie Soggetti
Geosciences, Interdisciplinary
Journal title
Comptes rendus de l'Academie des sciences. Serie II. Sciences de la terre et des planetes → ACNP
ISSN journal
12518050
Volume
322
Issue
3
Year of publication
1996
Pages
197 - 204
Database
ISI
SICI code
1251-8050(1996)322:3<197:TIOGOT>2.0.ZU;2-6
Abstract
An experimental approach is used to characterize the role of gold duri ng the formation of goethite and hematite from ferrihydrite. The resul ts show that metallic gold colloids play a role during the maturation of the gel at pH 7. In such conditions, the formation of goethite is r etarded in presence of colloidal gold. Cold does not affect the format ion of hematite. Dissolution/reprecipitation processes responsible for the formation of goethite are slowed down by electrostatic effects of the negative gold colloids on the concentration of Fe(OH); which coul d be a rate limiting factor for goethite precipitation. Also Au-O-Fe s urface complexes could slow down the formation of goethite.