ABSTRACT
A low concentration of fluoride in drinking water is beneficial for the development of teeth, while at higher concentrations beyond the permissible limit it causes fluorosis disease. The groundwater of several countries of the world is contaminated with fluoride. Africa, China, Pakistan, and South Asian regions including India are suffering from fluoride in water. The groundwater of the African and Indian regions is badly affected by fluoride. Therefore, there is an urgent need to assess clean and fluoride-free drinking water. Developing effective and potent technologies for the elimination of excess fluoride from contaminated water has become a prime need. The adsorption process is a well-considered method for pollutant removal from water. Adsorbents derived from biomass materials such as activated carbon, alumina, and clay have unique features such as selectivity, effectiveness, reusability, and cost-efficiency. This chapter focuses on the removal of fluoride mainly by an adsorption process using different adsorbents. Alumina, zeolite, chitosan, and activated carbon from various sources have been applied successfully for defluoridation of water. Carbon nanotubes and carbon–metal composites have been found to be good adsorbents, but their synthesis is very expensive. Some adsorbents from chemical synthesis have also been applied for defluoridation of water. Metal-modified carbon, clay, and alumina are found to be effective adsorbents for fluoride removal from the aqueous environment, and they should be applied for drinking water treatment.
