Efficient degradation of Amoxicillin in contaminated water using a dielectric barrier discharge throughput reactor

Abstract

Amoxicillin (Amx) is an emerging pollutant that is inadequately degraded by conventional wastewater treatment systems, posing significant risks to microbial populations and the environment. This study employed a dielectric barrier discharge throughput reactor to enhance Amx degradation. Optimal degradation occurred at an airflow rate of 1 lpm and a solution flow rate of 0.2 lpm, achieving a degradation rate of 0.07302 min^-1, as determined by ultraviolet-visible spectroscopy. Raman and Fourier transform infrared spectroscopy confirmed the breakdown of the β-lactam ring and the C-N bond in Amx. The treatment process operated at a power of 5.54 W, demonstrating an energy yield of 28.51 g kW^-1 h^-1 at 50% degradation and an electrical energy per order of 2.91 2.91 kWh m^-3 for Amx removal. The generation of reactive oxygen species was substantial, with hydroxyl radical concentrations reaching 24 mg L^-1 in the liquid phase despite the relatively low electron temperature and density, measured at 0.52 eV and 4.82 ⋅10¹² cm^-3 This suggests efficient diffusion of gaseous reactive oxygen species into the liquid phase, facilitated by bubble formation. Furthermore, toxicity assessments indicate that the degradation products exhibit significantly reduced toxicity to bacteria and cells, suggesting their safe environmental release.

Keywords: Amoxicillin; Dielectric barrier discharge; Reactive oxygen species; Throughput reactor; Toxicity assessments.