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In this work, aluminum net crafted (recycled) were used as TiO2 support for the treatment of textile dye Remazol golden yellow (RGY 150). The immobilization of 200mg of TiO2 was accomplished after aluminum net calcination. The following experiments were carried out in a photocatalytic bench reactor: preliminary tests, a 23 factorial experimental design with best system and the degradation kinetic in systems with TiO2 supported on aluminum net.It was observed characteristic peaks of aluminum and TiO2 (anatase and rutile) by XRD and the catalyst film formation was verified by SEM. The system UV/H2O2/TiO2 performed higher efficiency, with 99% of dye degradation in 50 minutes, followed by the system UV/H2O2/TiO2sp with 93% of dye degradation. Whereas the supported catalyst presents execution advantages and high degradation rates, the factorial design was realized for this system, displaying best degradation (100% degradation in 35 minutes). It was obtained k = 0.114 min-1 and R² = 0.994 in a pseudo-first-order model adjustment system. The use of artificial neural network was proven to be efficient to predict the degradation of a textile dye, with an absolute error of 0.0181. After treatment, there was a decrease of dye toxicity.

This work investigated the efficiency of polyethylene terephthalate (PET) as support material for TiO2 films in the photocatalytic degradation of red Bordeaux and yellow tartrazine dyes. The optimum operating conditions were determined by a factorial design, which resulted after 180 min of treatment in degradations of 99.5% and 99.1% for the UVC/H2O2/TiO2Sup and solar/H2O2/TiO2Sup systems, respectively. For the kinetic study, the experimental data fitted to the pseudo-first-order model and the calculated kinetic constants (k) values were 0.03 min−1 for the UVC/H2O2/TiO2Sup system and 0.0213 min−1 for the system solar/H2O2/TiO2Sup. It was verified that TiO2 supported in the PET remained with high degradation efficiency even after five cycles of reuse, indicating a good stability of the photocatalyst in the support. A significant reduction of TOC content was also observed along the reaction time. The phytotoxicity bioassay with Lactuca sativa demonstrated that after treatment with UVC/H2O2/TiO2Sup and solar/H2O2/TiO2SUP, an increase in IC50 and consequently lower toxicity was observed.