A PRELIMINARY-STUDY OF PULSED STREAMER CORONA DISCHARGE FOR THE DEGRADATION OF PHENOL IN AQUEOUS-SOLUTIONS

Pulsed corona discharges are shown in this investigation to be effecti ve at breaking down phenol in aqueous solutions in an isothermal batch reactor and in a semi-batch reactor with the continuous addition of o xygen. In the experiments where no oxygen was bubbled through the reac tor the phenol breakdown was independent of pH, thus indicating signif icant hydroxyl radical formation directly from the corona discharge. T he addition of iron was found to significantly enhance phenol degradat ion; this may be due to Fenton's reaction arising from hydrogen peroxi de formed directly by the corona discharge. In experiments where oxyge n was fed to the reactor, it appeared that two simultaneous reaction p athways contributed to phenol degradation. The first pathway consisted of corona-induced aqueous phase reactions. The second pathway arose f rom ozone production in the gas phase with subsequent mass transfer in to the liquid phase followed by liquid phase ozone reactions. The pres ence of phosphate and borate buffers decreased the rate and magnitude of phenol breakdown at low and high pH, respectively, due to radical q uenching.