Fotocatálise e adsorção com tio2 suportado em esferas poraver: análise da metodologia de impregnação e aplicação do modelo fast em simulações de reator de leito fixo para remoção de azul de metileno

Abstract

The growing demand for sustainable and efficient technologies for wastewater treatment has highlighted heterogeneous photocatalysis as a promising solution, with titanium dioxide (TiO2) playing a key role as a photocatalyst. Heterogeneous photocatalysis based on TiO2 has emerged as a promising approach for the removal of organic pollutants in wastewater, with methylene blue (MB) often used as a model contaminant. Structural modifications in TiO2, including doping and combinations with advanced oxides, have shown significant improvements in photocatalytic efficiency, achieving degradation rates above 99%. The incorporation of TiO2 into supports such as clays, zeolites, natural residues, and expanded glass spheres (EGS) has demonstrated potential in enhancing its structural stability, dispersion, and reusability. Systematic reviews indicate that the integration of TiO2 with different supports improves the structural stability of the photocatalyst and its reusability in photocatalytic systems, while also highlighting the influence of experimental factors such as the initial dye concentration and catalyst dosage. The use of sustainable light sources, such as sunlight, has also been identified as a promising alternative for process efficiency. Experimental studies evaluated the impregnation of TiO2-P25 onto expanded glass spheres, investigating the impact of increasing the impregnation cycles. It was observed that the removal of methylene blue (20 ppm) under LED-UV illumination (365 nm) improved by 5% per cycle, reaching a 50% higher efficiency in the 10th cycle compared to the first. However, excessive TiO2 deposition led to the formation of agglomerates and increased photocatalyst detachment, resulting in a 31% efficiency drop in the 10th cycle after material saturation. Furthermore, tests with the EGS@8xTiO2 material demonstrated great efficiency, achieving a performance 60% higher than the clean sphere and reaching 70% total methylene blue removal in 90 minutes. Simulations using the FAST tool were validated, showing excellent agreement with laboratory data. The optimization of operational parameters, such as flow rate, adsorbent mass, and initial dye concentration, proved to be crucial for maximizing system performance, highlighting its potential for industrial applications.