Sol-gel synthesis of Mn2O3/Al2O3/SiO2 hybrid nanocomposite and application for removal of organic dye

Nanocomposite of Mn2O3/Al2O3/SiO2 was prepared through an in situ sol-gel process, in which Mn2O3 nanocrystals were dispersed in the silica-alumina amorphous matrix. The synthesized products were studied by X-ray diffraction, thermogravimetric and differential thermal analysis, Brunauer-Emmett-Teller surface area analysis, UV-Vis spectroscopy and transmission electron microscopy. The nanocomposite was applied as a novel adsorbent for removal of methylene blue dye and the effect of heat treatment and contact time were studied. The results showed that nano-Mn2O3 particles were distributed on the surface of Al2O3/SiO2 and formed an activated surface charge. In addition, it was found that the nanocomposites removal rate strongly depended on the heat-treatment of absorbent.