Kinetics and product of ferrous iron oxygenation in aqueous systems

Iron is the fourth most abundant element by weight in the earth’s crust. The chemistry of aqueous iron primarily involves the ferrous (II) and ferric (III) oxidation states and is of interest in water supplies, wastewaters, limnology, and oceanography. Recent quantitative studies have included: iron removal mechanisms in estuarine and oceanic waters (1-3); adsorption of trace metals by hydrous ferric oxides or ferric oxyhydroxides (4-6); iron speciation and redox reactions in synthetic and real seawater (7-10). Although the oxygenation kinetics of ferrous iron have been studied extensively there is a rather wide spread in the reported rate constant. The present work was undertaken to study the effect of ionic media, alkalinity, and temperature on the kinetics of ferrous iron oxygenation and to identify the product(s) of oxygenation