Standard Gibbs free energies for transfer of actinyl ions at the aqueous/organic solution interface
Kitatsuji, Yoshihiro
; Okugaki, Tomohiko*; Kasuno, Megumi*; Kubota, Hiroki*; Maeda, Koji*; Kimura, Takaumi
; Yoshida, Zenko; Kihara, Sorin*
Standard Gibbs energies for transfer (
G
) of actinyl ions (AnO
; z = 2 or 1; An: U, Np or Pu) between an aqueous solution and an organic solution were determined based on distribution method combined with voltammetry for ion transfer at the interface of two immiscible electrolyte solutions. The organic solutions examined were nitrobenzene, 1,2-dichloroethane, benzonitrile, acetophenone and 2-nitrophenyl octyl ether. Irrespective of the type of organic solutions,
G
of UO
, NpO
and PuO
were nearly equal to each other and slightly larger than that of Mg
. The
G
of NpO
was extraordinary large compared with those of ordinary monovalent cations. The dependence of
G
of AnO
on the type of organic solutions was similar to that of H
or Mg
. The
G
of An
and An
were also discussed briefly.