Enhancing antibiotic degradation via photocatalysis and hydrodynamic cavitation using TiO2 catalyst supported on aluminum sludge

Revilla C.; Challco A.; Tejada K.; Terán R.; Garcia K.; Colina G. · Environmental Technology and Innovation (2025) · DOI: 10.1016/j.eti.2025.104030

Resumen

The antibiotic ciprofloxacin was used in photocatalysis and hydrodynamic cavitation tests with the TiO2 catalyst supported on sludge from a drinking water treatment plant (DWTS) chemically activated at 0.25 M (Q0.25). The catalyst precursor titanium (IV) isopropoxide was synthesized using a sol-gel method. Both the crude sludge (CS), Q0.25 and C1 (support material, 1:1, activated sludge (AS):TiO2) were characterized with SBET, XRD, SEM and FT-IR assays. The first tests were performed on a small scale (100 mL) and under constant magnetic stirring with light coming from a Class AAA solar simulator, in these tests the catalysts supported on Q0.25 at different ratios were tested (C1, C1.25 and C1.5). Then, the treatment was scaled up to a 4 L continuous flow system. Only C1 was used, keeping the same ratios in all experiments. The hydrodynamic cavitation and photocatalysis processes were combined for a better degradation of the antibiotic and in a shorter reaction time (60 min as opposed to 150 min in the first one). The proportion removed with the combined processes was the most successful one with a value of 0.741 and a k = 0.0123 min−1, improving its efficiency by almost 50 % compared to the photocatalysis process alone (0.488 and k = 0.006 min−1).

Instituciones: Universidad Católica de Santa María