Degradation kinetics and mechanism of emerging contaminants in water by dielectric barrier discharge non-thermal plasma: The case of 17β-Estradiol

A typical endocrine disrupting chemical 17β-Estradiol (E2) in aqueous solution was decomposed by using dielectric barrier discharge non-thermal plasma (DBD) created at the gas-liquid interface in pulsed mode. The results showed the peak voltage, E2 initial concentration, initial pH value and aqueous solvent of different characteristics have significant effect on the removal efficiency and the degradation rates of E2. After 30 min plasma treatment, 100% removal efficiency was achieved at E2 concentration of 100 μg/L with a peak voltage 12 kV and pH 5.6. Radical scavenger and complex environmental matrix could also be responsible for performance reduction in the degradation of E2 by DBD. The intermediate products were determined by liquid chromatography-mass spectrometry technique (LC-MS). Based on the intermediate products identified in the study, the possible mechanisms for the plasma treatment of E2 in ultrapure water by DBD were also proposed.