Catalyst Effect on Degradation of Organism by Nanoseconds Pulsed Discharge in Gas-Liquid Mixture*)

The gas-liquid mixed phase plasma generated by a streamer discharge in bubbles was used for degradation of acetic acid as treatment of organism pollution in water. The synergistic effect of plasma and catalyst, TiO₂ or Fe ions via electro-Fenton process, was utilized to enhance the production and utilization of hydroxyl radicals. When TiO₂ powder was added to acetic acid solution, the hydrogen peroxide (H₂O₂) concentration formed by the combination of OH radicals significantly increased more than 25%. Whereas, when a grounded electrode\ was replaced to Fe, iron ions appears in the solution and H₂O₂ was fully resolved into OH radicals in the electro-Fenton process, resulting in the degradation of acetic acid. The energy efficiency of degradation of acetic acid increased from 0.78 g/kWh to 1.18 g/kWh and 1.31 g/kWh with the addition of TiO₂ and replacement of iron electrode, respectively.