The efficacy of the VUV/O3 process run in a continuous-flow fluidized bed reactor for simultaneous elimination of favipiravir and bacteria in aqueous matrices.

The efficacy of the Vacuum UV/Ozonation (VUV/O3) process was evaluated for the degradation of favipiravir (FAV). It was found that coupling O3 and VUV resulted in a considerable synergistic catalytic effect on FAV removal. The VUV/O3 process performed better in moderately alkaline conditions than in acidic ones; complete FAV degradation and 99.4% TOC removal were achieved within 10 and 60 min, respectively. HO• played the dominant role in FAV degradation, with a second-order reaction rate constant with HO• at 1.05 × 1010 M-1 s-1. The VUV/O3 process could effectively treat tap water spiked with FAV. Efficient FAV and TOC removal, as well as total bacterial inactivation, was attained when treating municipal secondary effluent by the VUV/O3 process. Finally, the VUV/O3 process was operated in a continuous-flow mode in a fluidized-bed (FBR) reactor for treating FAV-spiked tap water. Complete degradation and 75.1% mineralization of 10 mg/L FAV were obtained at a hydraulic retention time of 1 and 8 min, respectively. The findings clearly suggest that the VUV/O3 process operated in a continuous-flow FBR is a promising, efficient technology for the removal of novel and emerging contaminants, such as the antiviral FAV.