Optimization of Photocatalytic Degradation of Methyl Orange Using TiO2

Abstract

The environmental contamination is one of the most significant problems today, especially when it comes to natural waters. In Brazil, the textile industry consumes approximately 20 tons/year of dyes and about 20% are disposed as effluents. For the degradation of these organic and inorganic contaminants, one can use a process called photocatalytic oxidation, which uses semiconductors such as TiO2. Many factors interfere with the photocatalytic activity. This study focuses on finding the best conditions for degradation of methyl orange, working on a variation of the TiO2 quantity and the temperature of the solution. Following the experimental plan, was standardized constant at 2.0 the pH of the solution containing the dye with a buffer mixture of HCl/NaCl. This degradation was accompanied by the decrease of the peak absorption of the dye spectrum. The process was optimized, and in 60 min it was possible to achieve the degradation of up to 95% of the dye.