SOL-GEL-MICROEMULSION TITANIA NANOPARTICLES AND ITS PERFORMANCE IN PHOTOCATALYTIC OXIDATION OF ACETIC ACID

摘要

Titania is one of the catalysts more employed in the last decades in the study of photocatalytic degradation of organic pollutants, in low concentration at room temperature. This technique is considered one of the new "advanced technologies of oxidation" for the air and water purification processes. When the pollutants are adsorbed on the titania photocatalyst employing UV o near UV irradiation they oxidize to environmentally benign compounds like CO_2 and H_2O. The size, shape, crystal structure and finally the surface structure determine the photoactivity of the catalyst. In this work we compare the ability for the photocatalytic degradation of nanoparticles obtained by sol-gel route in reverse micelles with different compositions of rutile/anatase phase. X-ray diffraction (XRD) patterns were used to determine the identity and size of each crystalline phase present. Finally, we chose acetic acid as a model of pollutant because many organic compounds that consist of two or more carbons react through an acetic acid intermediate.