This study concerned with the possibility of adsorption of some metal cations such as Cu2+ and Zn2+ on bentonite ore which were used as an inorganic fertilizer. Maximum adsorption was obtained at pH 5-5.5. The relationship between the amounts of metal cations adsorbed was found to follow the Freundlich adsorption isotherm. Preferential adsorption of both ions on adsorption sites was found to take place; Cu2+ is being adsorbed at greater extent than Zn2+. Bentonite samples which allowed adsorbing Cu2+ and Zn2+ were then subjected to desorption experiments using EDTA/OAc. Sequential leaching of the adsorbed ions revealed that the amounts of desorbed ion are linearly proportional to the amount previously adsorbed.
Adsorption, Cations, pH, Bentonite