An examination of the sorption characteristics of Am-241(III) and Eu(III) bound by humic substances chemically immobilized on silica gel

To facilitate investigations of the influence of humic substances on the mi gration of Am-241(III) in and around nuclear waste repositories we have che mically immobilized humic and fulvic acids on silica gels. It is anticipate d that these materials might serve as geochemical models of the humate-coat ed minerals that are likely to be present in the vicinity of the repositori es. The interaction of trivalent elements with humic substances have been i nvestigated by a batch method use of the derivatized silica gels from perch lorate solutions at different pHs. By using these novel solid phases, compl exing capacities and interaction constants are obtained at a constant ionic strength (0.1 M). The complexation of Am(III) is analyzed and compared wit h data in the literature.