New aluminum mesh from recyclable material for immobilization of TiO2 in heterogeneous photocatalysis

Abstract

AbstractThis study presents a new aluminium mesh made out of soda can rings as a support for titanium dioxide (TiO2) in the degradation of the synthetic dyes Bordeaux Red (BR) and Tartrazine (TT). Three pre‐treatments including calcination and acidification steps were investigated in order to select the most efficient immobilization procedure for photocatalysis application. Raw and titania‐aluminum meshes were characterized by scanning electron microscopy, x‐ray diffraction, diffuse reflectance, and Fourier transform infrared spectroscopy. The material presented itself as a suitable alternative in the immobilization of titania for wastewater treatment. Preliminary tests selected H2O2/TiO2(suspension) oxidation systems under natural sunlight and germicidal lamps (UVC) exhibiting 97.2% and 99.5% of degradation in 180 minutes, respectively. Immobilized TiO2 systems reached high degradation rates (>99%) after 180 minutes in both UVC and solar light‐based processes. An experimental planning study was carried out for the processes in order to find the best operational conditions and pseudo‐first‐order model fit well the removal data (discolouration rates of in the order of 0.0274 and 0.0145 min−1 for UVC and solar light systems, respectively). Parameters such as TOC, COD, and turbidity, revealed a great improvement in the environmental quality of the water after the treatment and acute toxicity bioassays demonstrated a significant decrease in toxicity for both systems after the treatments. The TiO2‐meshes demonstrated high performance in the removal after five cycles of operation. Therefore, the new immobilization procedure demonstrated that the TiO2‐aluminum mesh is a feasible option for wastewater treatment and photocatalysis.