Water, Vol. 10, Pages 36: Uptake of Zn2+ and As3+ from Wastewater by Adsorption onto Imine Functionalized Magnetic Nanoparticles Water doi: 10.3390/w10010036 Authors: Mike Ojemaye Omobola Okoh Anthony Okoh In this paper, imine functionalized magnetic nanoparticles (MNP-Maph) were employed to aqueous solutions for the uptake of Zn(II) and As(III). Characterization of the material showed the successful synthesis of this material. Factors affecting the uptake of metal ions in aqueous solution such as change in pH, time, adsorbent dose, adsorbate concentration, and temperature were investigated and optimized to determine the best experimental conditions for the effective adsorption of Zn(II) and As(III) from wastewater samples. The adsorption capacity of MNP-Maph followed similar patterns as that of amine functionalized magnetic nanoparticles (MNP-NH2) for the uptake of both metal ions from aqueous solution when solution pH was varied. Higher pH values favored the uptake of Zn(II) and As(III) by using both adsorbents. Also, increasing the contact time and temperature yielded a higher uptake of Zn(II) and As(III). Both processes can best be described with a pseudo-second order kinetic model, while the Langmuir maximum adsorption capacity (qm) for Zn(II) increased from 35.83 to 54.53 mg g−1, and for As(III) from 50.08 to 57.60 mg g−1. Of note is that the qm of As(III) was higher than that of Zn(II) because of the lower concentration of As(III) in solution compared to that of Zn(II), and thermodynamic parameters indicated that the adsorption processes were heat absorbing and rapid in nature. Experiments to evaluate if the adsorbent could be recycled showed excellent recyclability capacity of MNP-Maph after seven runs. Lastly, application of MNP-Maph for the uptake of Zn(II) and As(III) from municipal wastewater samples showed remarkable sorption performance confirming the potential of imine functionalized magnetic nanoparticles as an excellent adsorbent for the uptake of metal ions from aqueous solutions.
Energy, Environment Protection, Nuclear Power Engineering