The synthetic nano iron oxide (SNIO) was synthesized by co-precipitation method and characterized by XRD, SEM, FT-IR and EDAX. Commercial activated carbon (CAC) was further activated by acid treatment in order to enhance the adsorption capacity. Batch adsorption experiments were carried out to compare the adsorption efficiency of SNIO and CAC towards the removal of Co(II) ions as a function of initial concentration, dose rate, contact time, pH and stirring speed. The results show that SNIO have higher adsorption capacity of 99.2% towards Co(II) ion whereas CAC shows only 87.8%. The amount of Co(II) ion adsorbed per unit mass (qe) of SNIO was 19.31 mg g-1. For CAC the amount of Co(II) ion adsorbed per unit mass (qe) is only 3.38 mg g-1. The equilibrium adsorption isotherm data have been tested by applying both Freundlich and Langmuir adsorption isotherm. The separation factor R was found to be 0 to 1 for both the adsorbent; it clearly indicates feasibility of adsorption.
Adsorption, Nano iron oxide, Equilibrium