Uranyl mixed-ligand complex formation in artificial seawater

Abstract

The stability constants of the mixed uranyl-hydroxo-peroxo-carbonato species have been calculated. By incorporating those and including stability constants and corresponding equilibria into the developed model of seawater species distribution enables the dependence of uranyl species on pH to be evaluated. The calculations show that at seawater conditions (pH = 8), 88.3% of total uranyl-ion is in the form UO2(CO3)4, 11% is in the form UO2(CO3)2(OH)3, and 0.5% in the UO2(CO3)(OH)22 mixed-ligand complex form, while in the photic layer, 81.2% of uranyl-ion is in the tricarbonate complex, 10.1% in the form UO2(CO3)2(OH2)3, 7% as UO2(CO3)2(OH)3, 0.5% as UO2(CO3)(OH)24 and 0.5% as UO2(O2)2. 2 species. © 1993 Taylor and Francis Group, LLC.