caa a22 4500 37892737X CHVBK 20180305123621.0 cr unu---uuuuu 161128e20041101xx s 000 0 eng 10.1524/ract.92.9.583.55002 doi (NATIONALLICENCE)gruyter-10.1524/ract.92.9.583.55002 Carbonate complexation of neptunium(IV) in highly basic solutions [Elektronische Daten] [Akira Kitamura, Yukitoshi Kohara] The solubility of Np(IV) in carbonate media was studied for determination of thermodynamic data. The concentration of dissolved Np(IV) was measured with ionic strengths of 2.0 and 2.9M (M≡mol dm-3), hydrogen-ion concentration exponent (pHc=-log[H+]) of 12.0, 12.9 and 13.0, and with the total carbonate concentration (CT) from 5×10-2M to 7×10-1M by both oversaturation and undersaturation methods. It was found that the solubility of Np(IV) increased with increasing CT. Due to the dependencies of the solubility on CT and pHc, the dominant aqueous species of Np(IV) in highly basic solutions was expected to be NpCO3(OH)44-. Together with a carbonatohydroxo complex of Np(CO3)2(OH)22- estimated in our previous study, the apparent equilibrium constants of the carbonatohydroxo complexes were obtained at the respective ionic strength while the equilibrium constants at the zero ionic strength were extrapolated. The obtained equilibrium constants supported the literature values strongly, and contributed to improve the reliability of the thermodynamic data. © 2004 Oldenbourg Wissenschaftsverlag GmbH Laboratory techniques, experiments nationallicence Analytical chemistry nationallicence Inorganic chemistry nationallicence Kitamura Akira aut Kohara Yukitoshi aut Radiochimica Acta/International journal for chemical aspects of nuclear science and technology Oldenbourg Wissenschaftsverlag GmbH 92/9-11/2004(2004-11-01), 583-588 0033-8230 92:9-11/2004<583 2004 92 ract https://doi.org/10.1524/ract.92.9.583.55002 text/html Onlinezugriff via DOI 1 research article jats NATIONALLICENCE 856 40 https://doi.org/10.1524/ract.92.9.583.55002 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Kitamura Akira aut NATIONALLICENCE 700 1- Kohara Yukitoshi aut NATIONALLICENCE 773 0- Radiochimica Acta/International journal for chemical aspects of nuclear science and technology Oldenbourg Wissenschaftsverlag GmbH 92/9-11/2004(2004-11-01), 583-588 0033-8230 92:9-11/2004<583 2004 92 ract CC0 http://creativecommons.org/publicdomain/zero/1.0 nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-gruyter