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Access to safe drinking w ater has declined over the last decades in almost every
part o f the world. A m ong m any different water pollutants, fluorides play a major
role. Accumulation o f fluoride ions into natural w ater bodies largely happens
through waste w ater discharge from industrial practices and weathering
mineralization. Consumption o f excess amounts o f fluoride ions can cause both
dental and skeletal fluorosis. Even though, the acceptable values for fluoride ions in
drinking water recom m ended by W HO is 1.5 mg/L, recom m ended value o f fluoride
for topical countries such as Sri Lanka is 1.0 mg/L. This research highlights the
implementation o f m etal incorporated/coated bio-polymer system for the removal o f
fluorides ions from aqueous media. Naturally existing, low cost and highly
abundant polym er materials such as Alginate, Carboxy M ethyl Cellulose (CMC)
and Chitosan have been used as the m atrix material o f fluoride removal system.
Since rare earth metals such as La, Ce and Zr show strong affinity towards fluoride,
a tri-metal composite o f those m etals were synthesized using one step coprecipitation method. Characterized tri m etallic composite was incorporated into a
natural polym er to enhance fluoride removal efficiency. 1:1 ratio o f tri metal
composite incorporated alginate, CM C and chitosan beads and tri-m etal coated
alginate and CM C beads were synthesized separately. Freshly prepared 10 mg/L o f
fluoride solution w as used to determine percent removal o f fluorides and the
am ount o f fluoride adsorbed per unit. All adsorption experiments were carried out
in 250 mL plastic beakers w ith 100.00 ±0.01 m L test solution at pH 7.00±0.1 and
room tem perature (28 ± 1°C). Rapid adsorption o f Fluoride was observed within the
first sixty minutes and equilibrium was established within 2 hours. The amount o f
fluoride adsorbed per unit for CM C, Alginate, Chitosan and tri-m etal incorporated
alginate, CM C and chitosan w ere 2.47±0.09, 2.95±0.11, 1.01±0.80 mg/g and
4.703±0.09,4.67±0.08 and 1.07±0.03mg/g while tri-metal coated'alginate and CMC
were 3.77±0.004 and 2.98±0.06 mg/g. These composites were further studied using
FT-IR techniques. Carboxy M ethyl Cellulose-CM C, W orld H ealth OrganizationW HO, Fourier transform infrared spectroscopy- FTIR
