Cadmium Removal from Aqueous Solutions Using Pillared Clay with Modified Red Mud and Na-Bearing Bentonite

Document Type : Research Paper



A series of clay pillaring agents with Ti, Cu, Al and Fe elements were synthesized. These pillaring agents were used to modify montmorillonite clay by ion-exchange reactions. Clay d-spacings increased modestly when Na+-MMT clay was intercalated with these pillaring agents. The modified red mud (MRM) and pillared clay (PILC) complex can be used as a strong absorbent pollutant. In this study, MRM and PILC complex was used for the removal of cadmium from water. The complex was characterized using XRD, SEM and XRF microanalysis and adsorption of cadmium was studied as a function of pH, time, and temperature by AAS method. The maximum adsorption efficiency reached 96.69% when the pH was 6 at 40 ºC. Langmuir and Freundlich isotherms equation were used to fit the adsorption isotherms. It is evident from this study that MRM and PILC complex is a suitable material for the uptake of Cd (II) from aqueous solutions.


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