SYNTHESS MAGNETTENANOPARTICLES VIA SOLVOTHERMAL ROUTE : THEIR SURFACE CHARACTERIZATION AND APPLCATIONS FOR LANTHANDE ONS ADSOPTION

In this study, two crystal structure forms of magnetite (Fe3O4) nanoparticles were synthesized under two different solvothermal conditions. In one of which (EG-NaAc), ethylene glycol and NaAc were used as solvent and electrostatic stabilization respectively. In the another method (EG-NaOH), magnetite nanoparticles was prepared by the decomposition of chelate iron alkoxide complexes with diethylene glycol. Their surface characterization were made by scanning electron Microscope (SEM) and Fourier transform infrared (FT-IR) techniques. The result of SEM image showed that the average size distribution of both magnetites was less than 150 nm. Adsorption behavior of some lanthanide ions; La(III), Eu(III), Lu(III), Sm(III), Y(III) on these adsorbents were studied by batch method in aqueous solutions. The results of adsorption experiments showed that there was a large discrepancy between distribution coefficient (Ka) values of EG-NaAc and EG-NaOH compounds due to the low uptake of lanthanides by EG-NaAc compound. This phenomenon can be related to the difference in the hydroxyl groups concentration of two compounds. Because, the result of infrared spectra confirmed that the hydroxyl groups in EG-NaAc were much less than that of EG-NaOH. It should be noted that hydroxyl groups in magnetite surface are, indeed, the reactive parts which can react with acid or base. However, it can be replaced by other organic or inorganic anions to adsorb protons or metal cations, release water by heating etc.

کلیدواژه ها:

Magnetite nanoparticle ، Adsorption behavior