Abstract
A novel nanoadsorbent is synthesized through functionalization of hydroxyapatite with iron oxide (Fe3O4/HAP). It is applied as an efficient and economical adsorbent for green removal of toxic mercury (II) ions from water. Crystal structure and morphology of Fe3O4/HAP are characterized by XRD and SEM analyses. To its adsorption capabilities, the effect of dosage of adsorbent, contact time, initial pH and initial concentration of mercury ion are scrutinized. To evaluate adsorption behavior, isotherm models and kinetic equation are attended. The experimental data are fitted better to Langmuir isotherm model. The adsorption of mercury on Fe3O4/HAP follows pseud-second-order kinetics. Owing to high adsorption capacity of Fe3O4/HAP, 492.2 mg/g, Hg2+ can be removed considerably, up to 98 %, and the adsorption reaches equilibrium at approximately 10 minutes under optimized conditions. Probing thermodynamic parameters, the adsorption process appears endothermic in nature. Hg (II) adsorption capacity onto Fe3O4/HAP increases with enhancing in temperature.