Magnesium silicate doped with environmentally friendly extractants used for rare earth elements adsorption

New adsorbent materials using different doping methods were obtained. Magnesium silicate was doped with environmentally friendly extractants like sodium beta-glycerophosphate, tetraethylammonium bromide, and thiourea. The methods used were the dry method, the ultrasound unconventional method, and a new method, the pellicular vacuum solvent vaporization. The doped materials were characterized by Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), energy dispersive X-ray analysis (EDX), and determination of the specific surface area (BET). The usefulness of these materials and their performances were studied on the adsorption of rare earth elements Eu(III), Nd(III), and La(III). The best adsorption capacity of 16 mg/g was obtained for Eu(III) on magnesium silicate doped with thiourea. Nonlinear regression analysis of adsorption data was made employing Langmuir, Freundlich and Sips models.