Sorption and desorption of Co(II) on montmorillonite under ambient conditions as a function of pH, ionic strength and fulvic
acid are studied by batch technique. The results indicate that the sorption of Co(II) is dependent on pH, and ionic strength.
The sorption-desorption hysteresis is found in the desorption tests. Surface complexation is considered as the main sorption
mechanism of Co(II) on montmorillonite. The presence of fulvic acid (FA) enhances the sorption of Co(II) on montmorillonite.
Montmorillonite is considered as a promising candidate for the solidification and pre-concentration of Co(II) from large volume