FORMATION OF HYDROXYL RADICALS, HYDROGEN-PEROXIDE AND AQUEOUS ELECTRONS BY PULSED STREAMER CORONA DISCHARGE IN AQUEOUS-SOLUTION

The initiation reaction rate constants for the formation of hydroxyl r adicals, hydrogen peroxide, and aqueous electrons using a pulsed strea mer corona discharge in aqueous solutions are determined in the presen t study. The free radical scavenging property of carbonate ions was us ed to determine the initiation rate constants for the formation of hyd roxyl radicals and hydrogen peroxide from the pulsed streamer corona d ischarge. The effects of average current, voltage, and power input on the initiation rate constants were also studied. A reactor model inclu ding known chemical reaction kinetics was developed for the degradatio n of phenol, and the initiation rate constant for aqueous electrons wa s determined by fitting the experimental data of phenol degradation to the model. Transient concentration profiles predicted by the model we re compared to those of experiments for the formation of hydrogen pero xide in deionized water and for the degradation of hydroquinone. It wa s observed that the model results match experimental results satisfact orily for the formation of hydrogen peroxide and qualitatively follow the experimental results for the degradation of hydroquinone. The mode l was improved by considering that the reaction rate constants vary wi th the current in the reactor. The current was observed to vary with t ime for the cases where no salts were added to the reactor. It was obs erved that the improved model follows the experimental results satisfa ctorily for high initial concentrations (> 5.4 x 10(-5) M) of hydroqui none.