Dye-containing wastewater treatment by photo-assisted wet peroxidation using Au nanosized catalysts

摘要

BackgroundThe aim of this study is to test different supports on which to deposit Au nanoparticles and to determine the most suitable for Orange II (OII) dye degradation by a photo-assisted wet peroxidation (PWPO) process. The catalysts used (Au-Fe2O3, Au-TiO2, Au-ZnO and Au-Al2O3) were prepared by the deposition-precipitation method; a reference catalyst from the World Gold Council, hereafter denoted as Au-Fe2O3*, was also used for comparison. The catalysts were characterized in terms of surface area (S-BET), gold nanoparticles size, Au loading and Au oxidation state using several techniques (namely, nitrogen adsorption at -196 degrees C, X-ray photoelectron spectroscopy-XPS, and high resolution transmission electron microscopy-HR-TEM). Several runs were carried out for each material, to evaluate its efficiency in OII dye degradation by the PWPO process.