Quantification of reactive species generated in pulsed electrical discharge plasma reactor and its application for 17α-ethinylestradiol degradation in different water matrices

The degradation of a synthetic female hormone, a typical endocrine disruptor i.e., 17 alpha-ethinylestradiol (EE2), in water was studied using pulsed electrical discharge plasma reactor with multiple pin-plate electrode configuration at atmospheric pressure and room temperature. Various liquid phase reactive oxygen species generated in the system were also quantified to understand the scenario in depth. The effect of different operating parameters such as initial concentration of EE2, solution pH, presence of scavenger, purging of air and reactor overhead gases, different water matrices, humic acid (HA) and different ions on the removal kinetics of the reactor was probed in detail. The complete removal of EE2 was achieved in 15 sec of treatment time at concentration of 100 mu g L--(1) and the corresponding electrical energy per order and direct electricity cost were 2.43 kWh m(-3) and similar to 0.16 US$ m(-3), respectively. The plausible degradation pathways of EE2 in the reactor have also been proposed through the identification of intermediates. Further, algal acute toxicity test of all the treated samples revealed complete removal of toxicity. Thus, these findings demonstrated the promise of non-thermal pulsed plasma technology for degradation of EE2 at environmentally relevant concentrations.