Degradation of Nitrobenzene by Pulsed High Voltage Discharge in Water

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 mus-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.k Wh^-1 with the discharge voltage of 25 kV, discharge gap of 2.0 cm and the solution conductivity of 5.0 mus-cm^-1.