Aplicação fotocatalítica de TiO2 meso/macroporoso preparado através do método sol-emulsão-gel.

Abstract

The development of new alternatives seeking treatment of wastewater and industrial waste has been seen of great importance for the different sectors of society. The heterogeneous photocatalysis is one because it involves redox reactions caused by incidence of ultraviolet radiation (UV) on the surface of the semiconductor. In this process can be used titanium dioxide (TiO2) as the semiconductor heterogeneous photocatalysis. Thus, the study sought to test the efficiency of TiO2 meso / macroporous photocatalytic activity in the degradation of methyl orange dye. Such oxides were prepared by the sol-gel emulsion method. This process is advantageous, particularly for pore size control possibility (through the variation of the surfactant phase / oil) from the concentration and type of surfactant employed in the process. The obtained TiO2 pore size in the meso and macro scale is justified because the photocatalytic activity may be enhanced through a high surface area and porosity in this semiconductor. These foams were prepared using the no ionic surfactant Pluronic F-127 and anionic Sodium dodecyl sulfate, using as apolar phase Isopropyl myristate oil. The results obtained by means of photocatalysis showed increased photocatalytic activity influenced by the porous structure of these oxides obtained from the variation of the surfactant and the effect of nonpolar phase. While the emulsification changed properties, such as porosity, bulk density, number of macro / mesopores, among others, oxides. Thus, it was possible to obtain, through the photocatalytic tests, a higher photocatalytic activity for the sample prepared with the nonionic surfactant Pluronic F-127.