Abstract
A unified model for Fe(II) speciation and oxidation by molecular oxygen is described. This model combines Pitzer's concept of specific interaction with classic ion pair formation theory to describe ferrous iron speciation under conditions typical of natural waters. Using this model, it was determined that ferrous carbonate complexes [Fe(CO3), Fe(CO3)22-, and Fe(CO3)(OH)-] dominate the speciation of Fe(II) in natural waters containing greater than 1 mM carbonate alkalinity. The speciation data were then utilized to evaluate the species-specific rates of Fe(II) oxidation by molecular oxygen for a range of media compositions and ionic strength. At pH values below 6.0, the oxidation rate of Fe(II) is well described in terms of the Fe2+ and FeOH+ species. However, for pH values above 6, the Fe(CO3)22- complex is the most kinetically active species. The combined speciation/oxidation model for Fe(II) was successful at predicting observed oxidation rates in lake water, well-defined salt solutions, and seawater.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
