Magnetic nanocomposite of zinc-manganese ferrite/polyurethane foam for adsorption of copper and cadmium from water

The magnetic nanoparticles, zinc-manganese ferrite (Zn0.6Mn0.4Fe2O4), were chemically added to polyurethane foam (PUF) to obtain the polymeric nanocomposite Zn0.6Mn0.4Fe2O4/PUF. Characterization of the nanoparticles and the nanocomposite was made by X-ray diffraction, scanning electron microscopy, high-resolution transmission electron microscopy, and vibrating sample magnetometer. The prepared nanocomposite showed adsorption efficiency of 95% and 94% for Cu and Cd, respectively at a pH of 6.5, a shaking time of 60 min, and a composite dosage of 0.2 g. Adsorption kinetics followed a second-order model, with k(2) = 3.02 and 4.05 mg g(-1) min(-1) and adsorption capacity was 20.4 and 11.1 mg g(-1), respectively. The Freundlich model best described the adsorption isotherm, n = 0.93 and 0.88 and K-F = 0.64 and 0.31 L g(-1), and R-2 = 0.988 and 0.980, respectively. The quantification limits are 0.9 and 1.4 mu g L-1, respectively, with a pre-concentration factor of 125. The removal of Cd and Cu from tap, lake and river waters, yielding a recovery from 89%-116% relative standard deviation (RSD = 0.8%-8.6%).