Uranium (VI) in natural waters: Study of occurrence forms

A comparative study of U(VI) occurrence forms in natural waters has been conducted on the basis of experimental determination of the faction of U(VI) soluble and colloidal forms and the calculation of the specified forms by using the known stability constants. It was shown that the forms of U(VI) radionuclide in aqueous media could considerably change depending on the concentration of U(VI), carbonate ions, and suspended particles of different nature. It has been found out that uranium U(VI) at the level of its typical concentrations (several micrograms and less) occurs in natural waters in soluble different-metal and carbonate forms.