UV-Fenton Preoxidation for Phenolic Wastewater Biodegradability Enhancement

The effects of UV-Fenton preoxidation on the biodegradability of several phenolic wastewaters were investigated based on the ratio of BOD₅/COD. The results showed that the BOD₅/COD ratios of phenol, hydroquinone, 2-chlorophenol and coal-gas phenolic wastewater were less than 0.30, except for phenol in moderate concentration of 300mg/L, which mean that the phenolic wastewaters were difficultly biodegradable or non-biodegradable. The biodegradability of phenolic wastewater can be effectively enhanced by the UV-Fenton preoxidation. The BOD₅/COD ratios increase with the increase in the dosage of H₂O₂ during the UV-Fenton preoxidation. Therefore, it is feasible to improve the biodegradability of phenolic wastewater by controlling the degree of photo-Fenton reaction.