Effects of pH, ionic strength and fulvic acid on sorption of radiocobalt on montmorillonite and its Al-pillared and cross-linked
samples were studied using batch technique. The results indicate that the sorption of cobalt is strongly dependent on pH values
and independent of ionic strength. Fulvic acid enhances the sorption of cobalt slightly at low pH, but has no influence at
high pH values. Surface complexation is considered the main mechanism of cobalt sorption to montmorillonite. The sequences
of FA/Co2+ additions to the system did not affect cobalt sorption.