Adsorption of Vanadium Using Amberlite IRA-68 Resin from Aqueous Solution: Kinetics and Thermodynamics Studies

The current study was aimed at elucidation of the adsorption properties of Amberlite IRA-68 resin for vanadium ions in aqueous media. We investigated the effect of different parameters such as contact time, pH, initial concentration, temperature and adsorbent dosage on the uptake rate of vanadium. The findings showed that equilibrium data were best fitted by the Freundlich isotherm, and maximum adsorption capacity of the resin was 211.5 mg g-1 at 50 ◦C. The best possible pH for adsorption was 4.5. The first, and second-order reaction models and the Weber–Morris model were applied on the kinetics data. Among them, the best fitting was obtained by the second-order model. The rate controlling step at onset of the uptake was liquid film resistance, which gradually changed to intraparticle diffusion. Thermodynamic study revealed that adsorption was endothermic and spontaneous. The Amberlite IRA-68 resin could preserve more than 95% of its capacity after 8 cycles of adsorption/desorption.