An experimental study on biodegradation of nitrobenzene in groundwater and soil by indigenous microbes

Biodegradation is an important mechanism controlling the migration and fate of nitrobenzene in subsurface environments. To investigate the kinetics and it's affecting factors of the biodegradation process of NB under low concentrations and low temperatures, a series of batch experiments were carried out using uncontaminated groundwater, aquifer materials and the indigenous microbes contained. Results show that NB can be degraded effectively under concentrations of 0.112 mg/L-2.191 mg/L at 9 degrees C; increase in NB concentrations accelerates the biodegradation but results in a higher residual concentration; aquifer materials have a significant impact on biodegradation process. Biodegradation of NB is accelerated as the grain size of the aquifer material grows finer, which is probably due to increase in organic matter content of the aquifer materials and the "particle stimulation effect".