Ricerc@Sapienza

Yerba mate (Ilex paraguarensis, YM) was used as biomaterial for the removal of anionic and cationic compounds from wastewater. Chromium hexavalent Cr(VI), Remazol brilliant blue (RBB) and methylene blue (MB) were selected as pollutants. A calcination step was performed after the washing and drying steps to evaluate its effectiveness at increasing the adsorption capacity of the solid. Both YM and calcinated YM (CYM) were characterized by means of scanning electron microscopy (FE-SEM), Fourier transform infrared spectroscopy (FT-IR) and Brunauer-Emmett-Teller (BET) analysis.

TiO2-SiO2 mixed oxides have been prepared by the sol–gel technique from tetrabutyl orthotitanate and tetraethyl orthosilicate. The prepared materials were characterized by x-ray diffraction, scanning electron microscopy, energy dispersive x-ray spectroscopy, nitrogen physisorption, Fourier-transform infrared spectroscopy (FT-IR) and x-ray photoelectron spectroscopy (XPS). The results indicate that the TiO2-SiO2 mixed oxides have a large surface area and a nanoscale size. FT-IR spectra show that Ti atoms are bonded to silica by oxygen bridging atoms in Ti-O-Si bonds.