Removal of fluoride from water by natural biosorbents and evaluation of microstructure and functional groups in removal process

The study was aimed to remove the fluoride from aqueous solution by plant materials through batch experiment. The bio-adsorbents ( Manilkara zapota and peels of Solanum tuberosum ) were thermally activated and converted into ash. The batch study was performed in a laboratory and optimized by dose and time. The maximum removal of fluoride was observed in 0.8 g/100 ml for 77.6% and in 150 and 180 min for 77.6% in M. zapota and S. tuberosum . In the dosage optimization, the higher fluoride was removed in 77.6% in 0.8 g/100 ml in M. zapota and in 73% removal noticed for 0.8 g/100 ml in S. tuberosum . In IR spectra, M. zapota has showed several active functional groups such as Alkyl Halide, Alkyl, Alkene, Alcohol, Alkane and Amides that were recorded between 549.71 and 3192.19 cm −1 . The surface structure of micropores, rough surface, and crystalline clusters was observed in SEM analysis. The water quality parameters of the drinking water after biosorbtion of the biomaterials, maximum purity and good condition of water quality were observed in both, but M. zapota is a better sorbent. The plant materials are to be a suitable low-cost technique for the mass scale removal of fluoride from industrial effluents.