Biogenic nanozirconium in hydrogel beads for fluoride removal: equilibrium, thermodynamic and kinetic studies

Abstract

In the present research work, removal of fluoride from aqueous solution using fenugreek leaf mediated Zr nanoparticle entrapped in calcium alginate beads has been attempted. The adsorption study for removal of fluoride from aqueous solution of defined concentrations has been carried out in batch mode followed by its estimation using ion-chromatography. Synthesized Zr nanoparticles are subjected to various analyses e.g. SEM, TEM, SAED EDAX and FTIR, revealing zirconium an integral component. The adsorption capacity of Zr entrapped calcium alginate beads for fluoride is found to be 90.90 mg/g. The Langmuir isotherm model best fits on equilibrium data since it provides higher R² value than Freundlich model similarly, pseudo-second order kinetic model could better explain adsorption kinetic in comparison to pseudo first order model by presenting better correlation coefficient. The overall study suggests that Zr nanoparticles entrapped in alginate beads could be a better candidate for removal of fluoride from aqueous solution.