Studies on the physico-chemical behavior of 60Co, 106Ru and 144Ce in sea water

The physico-chemical behavior of radionuclides such as radiocobalt, radioruthenium and radiocerium in sea water was investigated by electrodialysis, high-voltage paper electrophoresis, and also by paper chromatography for nitrosylruthenium complexes. Most of the radiocobalt behaved as dialytic cations. However, these cationic species were not necessarily simple divalent, because their electrophoretic bands were rather diffuse and showed two peaks temporarily during ageing. The electroneutral form also increased with ageing. The radioruthenium in sea water showed relatively a number of well-defined species which could be readily classified into anionic, cationic, electroneutral, colloidal or particulate, non-dialytic and more or less adsorptive on vessel wall. The distribution of these species was dependent on their original chemical forms. The hydrolysis of higher nitro and nitratonitrosylruthenium complexes to lower ones was demonstrated with ageing by paper chromatography. The radiocerium showed initially cationic species. However, the electroneutral and anionic species were revealed with ageing by electrodialysis, and also they were strongly adsorptive on vessel wall, presumably because of the formation of colloidal hydrolytic species or particulates. (author)