M Kosari - Department of Energy Engineering, Sharif University of Technology, Azadi Avenue, Tehran, Iran
H Sepehrian - Nuclear Science and Technology Research Institute, End of North Karegar Avenue, Tehran, Iran

Removal of fluoride ions was investigated using a new adsorbent of yttrium alginate biocomposite (YALG). Effect of various parameters such as pH, contact time, initial concentration of fluoride ions and temperature on the sorption capacity of adsorbent was studied. Performing a mathematical assessment of fluoride sorption, isotherm and kinetics models including Freundlich & Langmuir isotherms and pseudo first & second order kinetics were applied on experimental equilibrium results through this work. Isotherm analysis revealed that Langmuir model showed a better evaluation from sorption equilibrium data than the Freundlich one. Based on kinetics evaluation, the pseudo secondorder equation was capable of fitting the sorption data satisfactorily than the pseudo first-order one. The maximum sorption capacity of fluoride ions (q, mg.g-1) using the YALG was found to be 147.05 mg.g-1. Regarding with thermodynamic studies and its parameters (i.e. ΔH°, ΔS° and ΔG°) it is revealed that the fluoride ions adsorption using nanoporous YALG was feasible, spontaneous and endothermic in nature.

Alginate Biopolymer,Yttrium,Fluoride,Adsorption,Nanoporous Yttrium Alginate Biocomposite,