Formation of Active Species by Bipolar Pulsed Discharge in Water

Water treatment by the direct electrical discharge in aqueous solution is an innovative advanced oxidation technology of water treatment. During the discharge processes, a large amount of high-energy electrons and active species, such as H
₂
O
₂
and O
₃
, are produced. Those active species directly react with organic molecules dissolved in water and oxidize them or even get them completely mineralized. In this paper, the concentrations of H
₂
O
₂
and O
₃
in a gas-liquid-solid mixture treated by bipolar pulsed discharges were measured. The effect of different experiment conditions on the H
₂
O
₂
and O
₃
concentration was investigated. Experimental results prove that bipolar pulsed discharges in a packed bed reactor have a better performance on H
₂
O
₂
and O
₃
generation than unipolar pulsed discharges. Besides, parameters, such as the discharge time, the applied voltage, the characteristics of the solid packing, and the gas flow rate, were positively correlated with the generation of H
₂
O
₂
and O
₃
. Essentially, the H
₂
O
₂
and O
₃
concentrations were mainly influenced by the single pulse energy that was also verified by experiments.