A Critical Study on Remediation of Fluoride Contaminated Water Using Encapsulated Active Growing Blue-Green Algae (Phormidium Sp.)

Fluoride concentrations in potable water that exceed the prescribed limit are always problematic. Encapsulating blue-green algae, Phormidium sp. in live, active form permits the formation of a novel type of bio-sorbent that perpetually generates new active biosorption sites due to the blue-green algae’s growth within the calcium alginate beads. In addition, encapsulation facilitates the removal of biosorbent from treated water. The experiment was carried out with modulation of parameters such as biosorbent dose (3-6 gm), initial fluoride concentration [F-] (2-5 mg/L), and pH (3.5-4.5) and then further optimized employing response surface methodology (RSM). In addition, a biosorption study reveals that an initial [F-] of 3mg/L removes 60% of fluoride. In addition, the Freundlich model was the best-fitting isotherm model for the biosorption study. In addition, first-order kinetics was observed throughout the entire investigation, and it was determined that both intra-particle diffusion and surface biosorption contributed to the rate-determining step. In addition, characterization techniques such as scanning electron microscopy (SEM)-Energy dispersive X-ray (EDX) and Fourier transform infrared spectroscopy (FTIR) confirmed the role of algal biomass in fluoride removal.