Removal of Cu (II) and Pb (II) from Aqueous Solution using engineered Iron Oxide Nanoparticles

Nano-sized Fe₃O₄ and Fe₂O₃ were synthesized using a precipitation method. The nanomaterials were tested as adsorbents for the removal of both Cu²⁺ and Pb²⁺ ions. The nanomaterials were characterized using X-ray powder diffraction to determine both the phase and the average grain size of the synthesized nanomaterials. Batch pH studies were performed to determine the optimum binding pH for both the Cu²⁺ and Pb²⁺ to the synthesized nanomaterials. The optimum binding was observed to occur at pH 4 and above. Time dependency studies for Cu²⁺ and Pb²⁺ showed the binding occurred within the first five minutes of contact and remained constant up to 2 hours of contact. Isotherm studies were utilized to determine the binding capacity of each of the nanomaterials for Cu²⁺ and Pb²⁺. The binding capacity of Fe₃O₄ with Cu²⁺ and Pb²⁺ were 37.04 mg/g and 166.67 mg/g, respectively. The binding capacities of the Fe₂O₃ nanomaterials with Cu²⁺ and Pb²⁺ were determined to be 19.61 mg/g and 47.62 mg/g, respectively. In addition, interference studies showed no significant reduction in the binding of either Cu²⁺ or Pb²⁺ to the Fe₃O₄ or Fe₂O₃ nanomaterials in the presence of solutions containing the individual ions Na⁺, K⁺, Mg²⁺ and Ca²⁺ or a solution consisting of a combination of all the aforementioned cations in one solution.