Author’s reply to “Comment on ‘Plutonium chemistry: a synthesis of experimental data and a quantitative model for plutonium oxide solubility’ by J.M. Haschke and V.M. Oversby”

In the accompanying letter, Newton and Hobart comment on a recent paper [J. Nucl. Mater. 305 (2002) 187] and conclude that a proposed alternative explanation for self-reduction of Pu(VI) is based on misinterpretation of data. Result of quantitative kinetic modeling contradicts this conclusion and the accepted explanation by showing that self-induced α-particle reduction of 239Pu(VI) at pH 1.5 does not account for the observed reduction rate of Pu(VI) or for dependence of the rate on [Pu(VI)]. Similar modeling shows that kinetic behavior is consistent with a self-reduction process based on disproportionation of Pu(VI). Validity of the alternative concept is supported by close similarities in the kinetic behavior of Pu(V) and Pu(VI).