Treatment of Nitrobenzene by Combination Electrolysis and Biodegradation

The wastewater in the presence of nitrobenzene was treated by simultaneous combination of electrolytic reduction and bio-reduction in an electrolytic bio-reactor, and the effects of current density and pH value on the removal of nitrobenzene were experimentally investigated. The result showed that with the increase in the applied current density (in the range of 0～20mA), the biomass densities at the electrodes decreased, while the removal rate of nitrobenzene and aniline yield increased. The optimal pH value for biodegradation was ca. 6.7 without current application, while 5.4～5.9 at a current density of 20mA. In the bio-reactor, the aniline concentration in the bulk liquid is lower than that near the cathode, but higher than that near the anode.