Degradation of pentachlorophenol by ozone generated by a pulsed power corona discharge

Ozone, generated by a pulsed power corona discharge, was used to degrade pentachlorophenol (PCP). The degradation of PCP was driven by ozone and superoxide radical (SOR). The corona discharge reactor was made without glass dielectric material, not only to reduce the power consumption but also to enhance the formation of the SOR. In addition, the corona discharge device was operated with pin-plate or pin-ring type electrodes, which had a normal and parallel oxygen flow, respectively. The ozone generated in the corona discharge reactor was in the range of 0-0.39 mg min(-1). To confirm the generation of SOR, the hydrogen peroxide was measured under acidic conditions without ozone effects. PCP at 10 ppm was completely degraded in 10 min in both electrode types with negative high DC voltage. The degradation rate of PCP was much greater at a high frequency (1 kHz). Oxalic, malonic and glyoxylic acids were generated as final products of the reaction.