Photocatalytic degradation of paracetamol under UV irradiation using TiO2-graphite composites

摘要

TiO2-graphite composites (TiO2-G) were prepared using different contents of powder graphite (G) and the obtained samples were characterized by different chemical-physical techniques. XRD and Raman results confirmed the presence of titania in anatase phase and, moreover, Raman spectra evidenced the presence of a band due to the graphite nanoparticles in the composite with an intensity that increased with the increasing of G content. From the UV-vis diffuse reflectance spectra it was evident a background absorption in the visible light region for TiO2-G composites whereas the band-gap energy value was similar to pure TiO2 and did not change with the increase of G content. Pure TiO2 and TiO2-G photocatalysts were used in the photocatalytic treatment of a solution containing paracetamol under UV light irradiation and the results are shown in terms of paracetamol degradation and total organic carbon (TOC) removal, evidencing an enhancement of photocatalytic performances due to the presence of G in the composites if compared with pure TiO2. The optimal G loading in TiO2-G composites was equal to 0.026 wt%, allowing to obtain the almost complete paracetamol degradation after 120 min of UV irradiation and a TOC removal of about 88% after 180 min of irradiation time.