Degradation of ciprofloxacin hydrochloride in a multiphase mixed system by subaquatic gas-liquid discharge plasma

Abstract

In recent years, antibiotic pollution has become a serious threat to human health. In this paper, a gas-liquid discharge plasma is developed to degrade ciprofloxacin hydrochloride in a multiphase mixed system containing inorganic and organic impurities. The discharge characteristics are analyzed by diagnosing the applied voltage and discharge current waveforms, as well as the optical emission spectra. The work investigates how degradation efficiency is affected by applied voltage, gas flow rate, treatment time, initial concentration as well as the addition of γ-Al2O3 pellets and peanut straw. After 70 min, the degradation efficiency of ciprofloxacin hydrochloride in the multiphase mixed system reached 99.6%. Its removal efficiency increases as the initial concentration decreases and the applied voltage increases. Besides, there is still a good degradation efficiency of ciprofloxacin hydrochloride with the addition of peanut straw. The degradation mechanism of ciprofloxacin hydrochloride is investigated through the analysis of degraded intermediates and reactive species.