DOI: https://doi.org/10.55373/mjchem.v28i4.14

Keywords: Advanced oxidation processes, degradation, ozonation, recirculating aquaculture systems, tetracycline

Abstract

This study examined tetracycline (TC) contamination in aquaculture and evaluated the efficiency of ozonation in removing TC from a recirculating aquaculture system (RAS). Ozonation parameters such as pH, contact time, and ozone dose were investigated in a laboratory-scale setup of a commercial RAS system. The study employed an ozone generator and ultraviolet-visible (UV-Vis) spectroscopy for analysis. The results show that the highest efficiency (84 %) was at an alkaline pH (pH 10), while a lower pH (pH 4) showed a decrease in efficiency (69 %). Concentration-dependent trends revealed reduced efficiency at higher initial TC concentrations, yet consistent degradation of at least 69 % for all concentrations after 30 min. Post-ozonation processes such as chemical oxygen demand (COD), biological oxygen demand (BOD₅) and total organic carbon (TOC) were measured at 27.2 mg/L, 3.9 mg/L and 3.9 mg/L, respectively. These findings suggest that future studies should focus on the application of catalytic ozonation or a combination of ozonation with other conventional treatments such as biodegradation or filtration, in order to achieve complete degradation of this toxic organic contaminant.