Per Persson
Dekan
Potentiometric and spectroscopic studies of sulfate complexation at the goethite-water interface
Författare
Summary, in English
The complexation of sulfate ions at the goethite-water interface has been studied by equilibrium measurements at 298.2 +/- 0.5 K and by infrared spectroscopy. A unified set of data from potentiometric titrations and batch adsorption experiments were evaluated according to an extended Constant Capacitance Model. The obtained equilibrium model consists of two outer-sphere complexes: = FeOH2+, SO42- (log beta(1,1,1(intr)(out)) = 8.3 +/- 0.03) and drop FeOH2+, HSO4- (log beta(2,1,1(intr)(out)) = 13.5 +/- 0.07) and an inner capacitance, C-1, of 4.5 and an outer capacitance, C-2, of 1.8. The outer-sphere model was confirmed by the infrared data and adsorption experiments at different ionic strengths. Furthermore, the infrared measurements provided direct evidence for protonation of the sulfate ions at the interface.
Publiceringsår
1996
Språk
Engelska
Sidor
2789-2799
Publikation/Tidskrift/Serie
Geochimica et Cosmochimica Acta
Volym
60
Dokumenttyp
Artikel i tidskrift
Förlag
Elsevier
Ämne
- Earth and Related Environmental Sciences
Status
Published
ISBN/ISSN/Övrigt
- ISSN: 0016-7037