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/TiO_2Sup and Solar/H₂O₂/TiO_2Sup 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/TiO_2Sup system and 0.0213 min⁻¹ for the system Solar/H₂O₂/TiO_2Sup. It was verified that TiO₂ supported in the PET remained with high degradation efficiency even after 5 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/TiO_2Sup and Solar/H₂O₂/TiO_2SUP an increase in IC50 and consequently lower toxicity was observed.

This work presents the study of tris(2-butoxyethyl) phosphate advanced oxidation in TiO₂-containing systems. Titania was immobilized on aluminum surfaces from recyclable materials and the results were compared with the suspension system. The initial concentration of photocatalyst and the oxidizing agent was optimized in a 2³ experimental planning and a kinetic study of the reactions was performed at the selected conditions. The experimental data were fitted to the pseudo-first-order model (rate constants estimated at 0.0129 ± 0.0009 and 0.0079 ± 0.0006 min⁻¹ for the systems with TiO₂ in suspension and immobilized, respectively). Artificial neural networks were also employed to model the experimental data and they presented correlation coefficients superior to 0.98 in all the training operations. After 5 cycles of degradation, the TiO₂-aluminum meshes exhibited a considerably low decrease in photocatalytic activity (inferior to 2%). Acute phytotoxicity assays demonstrated that the byproducts of the oxidation of TBEP molecules are less toxic than the raw samples regarding lettuce seeds. For both TiO₂ systems, COD decreased considerably as a consequence of the degradation. Immobilized TiO₂ system achieved similar degradation rates when compared to the suspension system.