A STUDY OF THE ADSORPTION KINETICS OF CHROMIUM PILLARED BENTONITE CLAY MINERAL

Chromium pillared bentonite clay was prepared by cation exchange reaction of the clay with a solution of chromium nitrate. Its capacity to adsorb heavy metal ions (nickel and lead) from solutions were studied in a batch adsorption system. The result showed that the amount of metal ions adsorbed was totally dependent on metal ion concentration, contact time and pH of the solution. This investigation also showed that the maximum sorption of the heavy metals occurred within 40 minutes at pH of 4-6. The uptake of the metal ions followed second order kinetics. The interactions of the heavy metal ions with the solid adsorbent showed a decrease in entropy and appreciable decrease in Gibbs free energy indicating a spontaneous sorption process. The results have demonstrated good potentiality for chromium pillared bentonite to remove heavy metal ions from aqueous solutions and polluted waters.