Abstract: Natural water contains fluoride in varying amounts. Fluorine is the 13th most abundant element of earth’s crust, represents about 0.3 g/ kg of earth’s crust. It occurs mainly in forms of chemical compound such as Sodium Fluoride (NaF) or Hydrogen Fluoride (HF) which is present in minerals fluorspar, topaz & cryolite. According to the World Health Organization suggested the optimum level of Fluoride is 0.3 to 0.7 mg/ L & the maximum level is 1.5 mg/ L. There are many methods have been developed for removal of fluoride from drinking water. These methods can be broadly classified into four basic groups; (1) Ion-Exchange or Adsorption methods, (2) Coagulation & Precipitation methods, (3) Electro-chemical defluoridation or Electro-Dialysis, (4) Reverse Osmosis. It has been reviewed the batch study process has been adopted to study the defluoridation of water using alum impregnated on brick powder. Alum and brick, when used individually are effective materials to cause defluoridation of water. But both the materials have certain limitations. Comparison of adsorption by Alum impregnated brick powder was made with adsorption by brick powder. Different parameters for instance, effect of pH, effect of dose and contact time of adsorbed fluoride is being studied and optimized. Fluoride removal was found to be 48.73 and 56.4 % from groundwater samples having 2.16 and 1.21 mg/L fluoride to 0.6 to 0.21mg/L respectively under the optimized conditions. Alum impregnated on brick powder has higher efficiency than the defluoridation by brick powder.
Keywords: Defluoridation, Adsorption, Brick powder (BP), Alum impregnated on brick powder (AIBP), Groundwater.