Adsorption studies for removal of trace copper metal ions from aqueous samples using magnetic nanoparticles

Abstract

Fe3O4 magnetic nanoparticles (MNPs) synthesized in-housed using co-precipitation method was assessed for the treatment of synthetic aqueous solutions contaminated by Cu(II) ions. Experimental results showed that at 25ºC, the optimum value for Cu(II) removal was pH 6.0 and an adsorbent dose of 60.0 mg. The adsorption capacity of Fe3O4 nanoparticles for Cu(II) is 16.28 mg g-1. Adsorption kinetic rates were found to be fast; total equilibrium was achieved after 180 min. Kinetic experimental data fitted very well the pseudo-second order equation and the value of adsorption rate constants was calculated to be 0.0006 and 0.0013 g mg-1 min at 5 and 40 mg L-1 initial Cu(II) concentrations, respectively. The equilibrium isotherms were evaluated in terms of maximum adsorption capacity and adsorption affinity by the application of Langmuir and Freundlich equations. Results indicate that the Langmuir model fits adsorption isotherm data better than the Freundlich model.