Adsorption of carbon dioxide on goethite (α-FeOOH) surfaces, and its implications for anion adsorption

Botryoidal Goethite: a Transmission Electron Microscope Study

“…Previous studies (Norrish and Taylor, 1961;Thiel, 1963) have shown that AI can replace Fe, and the existence of the isostructural groutite (a-MnOOH) suggests that Mn 3+ also replaces Fe in goethite. It is also well known that goethite can adsorb cations (e.g., Balistrieri and Murray, 1982) and anions (e.g., Parfitt et al, 1975), and Russell et al (1975) showed that COz is strongly sorbed by goethite as CO3 z-(and HCO3 ) ions. When Schwertmann and Taylor (1972) carried out experiments to determine the influence of silica on the transformation of lepidocrocite to goethite they found that the Si taken up during goethite formation is not in reversible adsorption equilibrium with the Si in solution.…”

Effect of monosilicate, phosphate, and carbonate on iron dissolution by mugineic acid

“…They suggested that silicate exerts a beneficial effect on the maintenance of iron availability. The adsorption of carbon dioxide on an iron mineral was observed by Russell et al (1975). Matocha and Mostaghimi (1988), however, reported that high concentrations of carbon dioxide in soil hardly affected the occurrence of iron deficiency in sorghum.…”

Calculation of site-specific carbon-isotope fractionation in pedogenic oxide minerals

“…The occupation of the pseudochannels in goethite by carbonate ions was postulated Ͼ30 years ago (12) and has been understood to be the main mechanism by which carbonate ions are incorporated into goethite. If this is the case, and the carbon-isotope composition represents an equilibrium fractionation, our calculations indicate a highly 13 C-depleted isotopic signature for CO 2 (m).…”

“…In contrast, occlusion of CO 2 in oxide soil minerals at trace concentrations could involve multiple sites with varying populations, possibly depending on the kinetics and conditions of soil formation. For goethite, it has commonly been assumed that the open pseudochannels parallel to the c crystallographic axis are the major host for CO 2 (m) (12), but this has not been definitively demonstrated, and it is possible that other types of sites could be involved in the uptake of CO 2 (m). An important question is then whether the various kinds of CO 2 (m) sites would have large differences in their equilibrium 12/13 C isotope fractionation factors.…”