OBJECTIVEIn this study, we examined the biodegradation of Dichloroethylene (DCE) by two strains of aerobic bacteria.

METHODSUsing batch experiments, we measured the biodegradation rates of DCE and the residual concentrations of DCE for each bacterial strain. The varying trends in biodegradation rates with different initial concentrations of DCE were fitted to kinetic models.

RESULTSThe biodegradation kinetics of DCE by the strain DT-X, which uses toluene as co-metabolic substrate, fitted the Monod model (corresponding parameters: v(max)=0.0075 h(-1), K(s)=2.12 mg/L). The biodegradation kinetics of DCE by the strain DT-M, which uses 1,1-Dichloroethylene as single substrate, fitted the Haldane model (parameters: v(max) =0.0046 h(-1), K(s)=4.25 mg/L, K(i)=8.47 mg/L).

CONCLUSIONThe substrate removal rate constant of 1,1-Dichloroethylene of the co-metabolic strain DT-X was much higher than that of strain DT-M. The substrate removal rates obtained from both bacterial strains in this study were higher than those reported in similar studies.