Degradation of Nitrobenzene by Pulsed High Voltage Discharge in Water

Abstract

Degradation of nitrobenzene by pulsed high voltage discharge in water, including the effects of discharge conditions and energy efficiency, has been primarily investigated using a needle-plate electrode pair. With the increase of applied voltage, decrease of discharge gap and conductivity of solution, nitrobenzene degradation rate increases. The 12 mg·L -1 nitrobenzene solution removal rate can reach 23.1% after discharged 60 minutes using needle-plate electrodes with a gap of 2.0 cm, an applied voltage of 45 kV and solution conductivity of 5.0 µs·cm -1 . The nitrobenzene degradation is considered to be related to the hydroxyl production in the discharge process. Part of the electric energy became heat of the solution for the solution temperature increase could be detected in the experiment. Energy efficiency analysis showed that low voltage, low discharge gap and low conductivity were favorable in the degradation. An optimum G value can reach 0.175 mmol·kWh -1 with the discharge voltage of 25 kV, discharge gap of 2.0 cm and the solution conductivity of 5.0 µs·cm -1 .

Treatment of olive oil mill wastewater by a pulsed high‐voltage discharge process; process optimization and combination with Fe+2 and H2O2

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Effect of Pulsed High-Voltage Discharge Process Combined with H2O2 and Fe2+ on Degradation of Phenol

“…If the gap between electrodes is small, a spark discharge can occur on several needle points, and the corona discharge intensity of other points will descend rapidly on the same time; if the gap is big, the intensity will also be reduced because of the weakened electrical field34 . Shidong et al35 reported that when the discharge gap was 4 cm, only weak corona could be seen near the needle electrode. When the discharge gap was shortened, the discharge became intense and the discharge streamers immerged and stretched to the plate electrode.…”