REMOVAL OF FLUORIDE FROM WASTE WATER OF ALUMINIUM SMELTER BY ALUMINIUM ION LOADED ION EXCHANGE RESIN

Strong Acid Cation resin has sulphonic acid functional group (H+ form) possessing appreciable defluoridation capacity, which has been enhanced by chemical modification into Al3+ form by loading of Aluminium ions in H+ form of resin. The defluoridation process in case of Al3+ ion loaded resin was found to be 480 mg F-/kg, at 15 mg/L initial fluoride concentration. The nature and morphology of sorbents are characterized using XRD, FTIR and SEM analysis. The fluoride sorption has been explained using the Freundlich, Langmuir and Redlich-Peterson isotherms models. The calculated thermodynamic parameters such as Delta G degrees, Delta H degrees, Delta S degrees and sticking probability (S*) explains the nature of sorption. A Defluoridation Plant is in service at Aluminium Smelter of National Aluminium Company for treatment of the waste water for removing Fluoride and reutilise the water to minimise the water loss.