Reuse of Alum impregnated Bio-Sludge as defluoridating adsorbents

摘要

Several methods have been suggested for removing excess fluoride in water. The process of removal of excess fluoride from water is described as defluoridation. One of such methods is adsorption. Present study has been conducted to investigate the efficacy of alum impregnated sludge of sewage treatment plant as defluoridating adsorbent material. The experiment has followed batch process. The effect of pH, contact time, adsorbent dose and fluoride concentration on removal efficiency of fluoride has been studied in detail. 78% removal has been achieved after giving a 270 minutes contact time. The adsorption kinetics has been found to follow first order rate mechanism as well as Freundlich and Langmuir isotherm model. The optimum pH range was found to be 6.50-7.5 and adsorption equilibrium was found to be 270 minutes after conducting the experiment with different initial concentrations.