Details zur Publikation

Kategorie Textpublikation
Referenztyp Zeitschriften
DOI 10.1071/EN10125
Titel (primär) FeII oxidation by molecular O2 during HCl extraction
Autor Porsch, K.; Kappler, A.
Quelle Environmental Chemistry
Erscheinungsjahr 2011
Band/Volume 8
Heft 2
Seite von 190
Seite bis 197
Sprache englisch
Keywords abiotic oxidation; biogeochemistry; geomicrobiology; iron minerals; soil extraction
Abstract HCl is commonly used to stabilise FeII under oxic conditions and is often included in Fe extractions. Although FeII oxidation by molecular O2 in HCl is described in the field of hydrometallurgy, this phenomenon has not been systematically studied in environmentally relevant systems. The extent of FeII oxidation by O2 during extraction of soils and magnetite by HCl and in HCl/FeCl2 solutions was therefore quantified. FeII was stable in 1 M HCl at room temperature for several days, whereas in 6 M HCl at 70°C, 90% of the FeII was oxidised within 24 h. In the absence of O2, no FeII oxidation occurred. Experiments at low pH with increasing H+ or Cl concentration alone and geochemical modelling suggested that the formation of complexes of FeII and HCl may be responsible for the observed FeII oxidation. The use of strictly anoxic conditions for Fe extraction by HCl to obtain reliable Fe redox speciation data is therefore recommended.
dauerhafte UFZ-Verlinkung
Porsch, K., Kappler, A. (2011):
FeII oxidation by molecular O2 during HCl extraction
Environ. Chem. 8 (2), 190 - 197 10.1071/EN10125