Pharmaceutical degradation by a plug-flow ozone nanobubble reactor: Reaction time and matrix effects
Year: 2026
Type: article
Abstract: This study investigated the performance of ozone nanobubbles for the degradation of six representative pharmaceuticals, including ibuprofen (IBU), acetaminophen (APAP), metronidazole (MTZ), carbamazepine (CBZ), sulfamethoxazole (SMX), and naproxen (NPX), in a plug-flow reactor under different operating and water-matrix conditions. At an inlet ozone concentration of 1.5 mg/L, shortening the reaction time from 60 to 5 min increased IBU degradation by 20% and improved ozone utilisation efficiency. At 5 min, APAP, CBZ, SMX, and NPX were almost completely degraded during simultaneous treatment in deionised water, whereas MTZ degradation decreased from 88% under individual degradation to 62% in the pharmaceutical mixture, indicating greater sensitivity to coexisting contaminants. The degradation of all six pharmaceuticals in the secondary-treated effluent matrix was lower than in deionised water, possibly due to background organics and other matrix effects. Pharmaceutical degradation was pH-dependent and among the pH conditions investigated, pH 9 resulted in the highest simultaneous pharmaceutical degradation efficiency. Increasing the solution pH to 11 or 12 resulted in complete ozone consumption but lower pharmaceutical degradation and ozone utilisation efficiency. These findings demonstrate that effective ozone utilisation, rather than prolonged reaction time or complete ozone consumption, is critical for continuous-flow ozone nanobubble treatment.
Language: English
Subfield: Water Science and Technology
Field: Environmental Science
Domain: Physical Sciences
Open Access status: hybrid
Estimated APC paid: $3,350
Funder: Australian Research Council
OpenAlex ID: W7223680229