Marbofloxacin mitigation by simultaneous process of adsorption and advanced oxidative process: An approach to the degradation mechanism and evaluation of the eco-toxicological impact using the QSAR tool.

The present study investigated the adsorption and oxidation of the antibiotic Marbofloxacin (MBX) individually and simultaneously. The concentrations of MBX were monitored over time to assess the efficiency of the simultaneous process besides High-Performance Liquid Chromatography (HPLC) was employed to quantify the MBX degradation. An experimental design of three Box-Behnken Factors was performed to study the influence between the variables. To adsorption as an individual method, the best conditions were achieved at a pH of 7.8, 0.85 g of activated carbon, and a contact time of 42 min. To Fenton, the best conditions were achieved at a ratio of 6.25 (r = [H 2 O 2 ]/[Fe²⁺]) and a time of 30 min. The final concentration reached by adsorption and Fenton as individual processes were 0.49 and 0.12 mg L⁻¹, respectively, while the concentration of MBX in the simultaneous process reached a final concentration of 0.078 mg L⁻¹. The results indicated that the simultaneous process exhibited greater efficiency in decreasing MBX concentration when compared to individual processes. The formation of degradation products also decreased after treatment, suggesting the potential environmental safety of the combined treatment. Finally, to further comprehend the environmental impact of MBX in water, a toxicity Quantitative Structure-Activity Relationship (QSAR) analysis was conducted to predict its potential toxicity, enabling a more thorough assessment of its ecological risks. It was concluded, that the method offers promising implications for environmental safety. • It was achieved a final concentration after adsorption and Fenton of 0.49 and 0.12 mg L⁻¹, respectively. • The final concentration of MBX in the combined process was 0.078 mg L⁻¹. • The simultaneous implementation reduced the generation of degradation byproducts that may be toxic. • QSAR tool showed the results of the toxicity comparing with MBX concentration was below the values considered toxic in aquatic environments in tests. [ABSTRACT FROM AUTHOR]