Modeling the aqueous reaction kinetics of estriol with ferrate

Abstract

In this study the aqueous oxidation kinetics of estriol (E3) by potassium ferrate (K₂FeO₄), a chemical for its strong oxidizing power and for producing a coagulant from its reduced state (i.e. Fe(III)), was evaluated in the range of pH 8-12 with different molar ratios of the reactants. As the degree of Fe(VI) protonation varies with the solution pH, it was found that a first order model was not suitable to describe the oxidation reaction. This paper describes a theoretical representation that closely models the reaction kinetics of E3 and ferrate. From this modeling, the reaction rates of HFeO_4^{-}and FeO_4^{2-}with E3 have been determined. The results show that the reactivity of HFeO_4^{-} with dissociated and undissociated E3 is greater than that of FeO_4^{2-}, and that E3 is more reactive in its dissociated state.

Keywords

ferrate / estriol / endocrine disruptor / kinetics / oxidation

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