A batch adsorption process was chosen on charcoal made from locally available trees viz- Prosopis Spicigera, Azadirachta Indica and Acacia Nilotica to assess their suitability for removal of fluoride from fluoride contaminated water. The efficiency of adsorption of fluoride was found to depend on physical parameters like dose of the adsorbent, pH, contact time, stirring rate, particle size of the adsorbent and initial adsorbate concentration in water. These parameters were studied to find out their optimum values for the uptake of fluoride. The fluoride removal efficiency in all the three adsorbents studied was found to be 96% (Prosopis Spicigera), 93.3% (Azadirachta Indica) and 72% (Acacia Nilotica). The optimum adsorbent doses were found to be 12 g/L for Prosopis Soicigera, 16 g/L for Azadirachta Indica and 18 g/L for Acacia Nilotica. Equilibrium was achieved in 2 hr for Prosopis Spicigera as well as for Azadirachta Indica and 90 min for Acacia Nilotica, an enhanced adsorption was obtained at pH 2. It was found that the adsorption of fluoride on these charcoals follows the Langmuir isotherm.
