MECHANISTIC VIEW IN DEFLUORIDATION OF WATER BY VARIOUS BIOSORBENTS OVER A DECADE - A REVIEW

摘要

Fluoride is one of the contaminants which is found in excess in surface or groundwater because of geochemical reactions or anthropogenic activities. The problem of high fluoride concentration in groundwater resources has become an important health-related geo-environmental issue in some areas. Fluoride concentrations in the range of 1.5-4 mg/L result in dental fluorosis whereas with prolonged exposure at still higher fluoride concentrations (4-10 mg/L) dental fluorosis progresses to skeletal fluorosis. Among various methods used for defluoridation of water such as coagulation, precipitation, membrane processes, electrolytic treatment, ion-exchange, the adsorption process is widely used. It offers satisfactory results and seems to be a more attractive method for the removal of fluoride in terms of cost, simplicity of design and operation. This review is listed on efficiency of different biomass for the sequestration of fluoride from water by using adsorption technique. The efficiency of biomass in eliminating fluoride is studied with different parameters such as pH, equilibrium time, adsorbent dose, temperature, initial fluoride concentration and maximum sorption capacity.