Optimization of a bioelectrochemical system for 2,4-dichloronitrobenzene transformation using response surface methodology.

In the present study, a bioelectrochemical system (BES) was developed for 2,4-dichloronitrobenzene (DClNB) transformation. Response surface methodology (RSM) was applied to optimize the operational conditions, including the V / S ratio (volume of the BES/size of the electrode ratio), interval ( D ) (distance between the anode and cathode) and position ( P ) (proportion of the electrodes immerged in the sludge). The optimum conditions for the V / S ratio, interval and position were 40, 2.31 cm and 0.42. The pollutant removal rate and increase in Cl - were 1.819 ± 0.037 mg L -1 h -1 and 11.894 ± 0.180 mg L -1 , which were close to the predicted values (1.908 mg L -1 h -1 and 12.485 mg L -1 ). A continuous experiment indicated that the pollutant removal efficiency in the BES with 50% of the electrodes immerged in the sludge was 34.6% and 22.6% higher than that in the ones with 0 and 100% of the electrodes immerged in the sludge.