Coupled photo-Fenton–biological system: effect of the Fenton parameters such as residual H₂O₂, Fe^2 + and pH on the efficiency of biological process

Abstract

The aim of this research work is to evaluate the performance of packed-bed bioreactors under typical conditions of photo-Fenton treatment (residual iron, residual hydrogen peroxide, acidic pH). The target pollutant selected was 4-Chlorophenol which is included in the list of Priority Substances (Decision No 2455/2001/EC) in the field of water policy and amending Directive 2000/60/EC. It was found that the biological process operated correctly during eight days when the pH was in the range of 3.5–7. In the same way, the presence of hydrogen peroxide in similar concentrations to that used in the photo-Fenton process was not negative on the biological activity. On the other hand, the presence of residual iron in the biological treatment could not be observed as a consequence of the optimal dosage used for the photo-Fenton treatment. The iron dosage is still low enough to ensure non-inhibitory effects. The results obtained in this study can provide a practical knowledge for a real application.