Defluoridation of Groundwater using Low Cost Adsorbent like Bagasse Dust, Aluminium Treated Bagasse Flyash, Bone Powder and Shell Powder

Excessive fluoride concentrations have been reported in groundwaters of more than 20 developed and developing countries including India where 19 states are facing acute fluorosis problems. Various technologies are being used to remove fluoride from water but still the problem has not been rooted out. The present study was undertaken for the determination of fluoride ions in drinking water in the Agra?s urban as well as rural region. Batch tests on groundwater samples from the different sites as St. John?s College Chemistry Department, Trans Yamuna, Gokulpura and Dareshi that contained 2.0, 2.5, 3.5 and 4.2 mg/l of fluoride respectively were conducted using bagasse dust (BD), bagasse flyash (BF), aluminium treated bagasse flyash (ABF), buffalo bone powder (BP) and clam shell powder (SP). The tests were also carried out with 1.9, 3.8, 4.75 and 9.50 mg/l NaF solutions. The work aimed to evaluate the feasibility of using these biomaterials for the removal of fluoride ions from groundwater to make it fit for drinking or industrial use. Defluoridation was in the order of SP > BP > ABF > BF > BD over a wide range of initial concentration 1-10 mg/l at sorbent dose range 1-20 g/l, pH 6.0, temperature 25?C, rpm 150 for 5 h. The sorption increased with increasing contact time and sorbent dose but the equilibrium was attained after 4 h for most of the sorbents. Groundwater samples showed 2 to 10% lower removal as compared to standard NaF solutions under similar conditions. The clam shell was found to be the best of all the fluoride removing agents studied here