High-Temperature Reaction Kinetics of the eaq- and HO2• Radicals with Iron(II) Ions in Aqueous Solutions

Abstract

Pulsed electron radiolysis was used to determine the chemical reaction kinetics and Arrhenius parameters for iron(II) reactions in aqueous solutions under irradiation. The second-order Fe2+ reactions with the hydrated electron (eaq-) and the perhydroxyl radical (HO2•), arising from water radiolysis, were measured to high temperatures using custom-built flow-through cells with a multichannel optical detection system. The reaction with the HO2• radical was found to proceed via the formation of a metal-ion adduct species, Fe2+-HO2•. The adduct’s molar extinction coefficient and its first-order decay rate coefficients are also reported.