Comparative studies of fluoride removal from groundwater by calcium carbonate, activated alumina and activated punica granatum Ash

This study investigates the comparative feasibility of three low-cost adsorbents namely calcium carbonate, activated alumina and activated Punica granatum ash (APGA) for the removal of fluoride ions by adsorption from groundwater of Raebareli district of India. The effect of various process parameters like pH, contact time, adsorbent dose, etc. have been investigated by batch adsorption technique. Experimental results revealed that fluoride adsorption increases with increasing adsorbent dose. Fluoride adsorption increased with increasing contact time and reached equilibrium at 100 min for all the three adsorbents. The maximum fluoride adsorptions occurred at 4.7, 1.03 and 3.34 mg/g of calcium carbonate, activated alumina and activated Punica granatum ash, respectively. All the adsorption experimental data of calcium carbonate, activated alumina and activated Punica granatum ash were fitted well with the Langmuir isotherm and followed pseudo-second-order kinetics.