Synthesis and characterization of magnetite nanoparticles from polyol medium for sorption and selective separation of Pd(II) from aqueous solution

• Published in: Journal of alloys and compounds 2020-01, Vol.812, p.152041, Article 152041
• Main Authors: Rizk, H.E., El-Hefny, N.E.
• Format: Article
• Language: English
• Subjects: Aqueous solutions; Chemical precipitation; Coated particles; Coating; Ethylene glycol; Fission product; Fission products; Image transmission; Iron oxides; Magnetic properties; Magnetite; Mathematical models; Morphology; Nano-particles; Nanoparticles; Palladium; Parameters; Polyol medium; Separation; Sorption
• ISSN: 0925-8388; 1873-4669
• DOI: 10.1016/j.jallcom.2019.152041

Magnetite nanoparticles were synthesized by reverse co-precipitation method using iron salts in alkaline medium, in presence of ethylene glycol (EG) or diethylene glycol (DEG) as polyol solvents. The morphology and magnetic properties of pure magnetite and modified magnetite were characterized by different techniques. X-ray diffraction (XRD) studies support the presence of a highly crystalline Fe3O4 phase and the coating of DEG or EG did not affect the composition of magnetite. Transmission electron microscopy (TEM) image showed that the shape of Fe3O4, DEG coated particles and EG coated particles were spherical with a nano size of mean diameter 18.8, 14.45 and 10.49 nm, respectively. The usability of EG-coated magnetite for the sorption of Pd(II) from aqueous chloride solution was investigated by batch experiments. Parameters affecting the uptake of palladium metal ion were studied. The kinetic studies and the isotherm data were described using different models. Experimental data showed that the sorption process could be quite fitted with pseudo-second order kinetic and Langmuir models. In addition, thermodynamic parameters were evaluated to expect the nature of sorption. Further, the desorption of Pd(II) from EG/MNPs was achieved using 5.0 mol/L HNO3 solution, and the nano-magnetite was reused effectively. Finally, the separation possibility of palladium from some fission products was achieved successfully. Effect of initial pH on the removal percentage of 100 mg/L of Pd(II), Co(II), Cd(II), Cu(II), Zn(II), Ni(II) and Sr(II) onto 0.05 g modified magnetite. [Display omitted] •Nanoparticles were synthesized by reverse co-precipitation method in presence of ethylene glycol or diethylene glycol.•The magnetic properties and the particle size of the original Fe3O4 MNPs and DEG coated MNPs or EG coated MNPs were approved by VSM and TEM.•EG/MNPs exhibited excellent efficiency for Pd(II) uptake in comparison with DEG-MNPs, from aqueous medium according to higher–OH group on EG than on DEG.•EG coated MNPs displayed good efficiency and selectivity of the separation of Pd(II) from some metal ions as fission products.