Degradation of Azo Dyes in Aqueous TiO2 Suspensions employing UV and Visible Radiation

SATUF, M.L.; PIERRESTEGUI, M.J.; BRANDI, R.J.; ALFANO, O.M.

São Paulo/SP y Cubatão/SP, Brasil

Workshop; V Encontro sobre Aplicações Ambientais de Processos Oxidativos Avançados-V EPOA; 2009

Azo dyes present in wastewaters from the textile industry constitute a major threat to the environment due to their toxicity, non-biodegradability and potentially carcinogenic nature. Heterogeneous photocatalysis with titanium dioxide (TiO2) has been proposed as an effective method to degrade this kind of pollutants. The degradation mechanism of the dye depends on the wavelength of irradiation. Radiation in the UV range can induce charge separation in the TiO2 particle. On the other hand, under visible light, initial excitation of dye molecules occurs.