Effects of DOM Characteristics from Real Wastewater on the Degradation of Pharmaceutically Active Compounds by the UV/H2O2 Process

The characteristics of dissolved organic matter (DOM) can significantly affect the degradation of target compounds by the advanced oxidation processes. In this study, the effects of the different hydrophobicity/hydrophilicity fractions, molecular weight (MW) fractions, fluorescence components and molecular components of DOM extracted from municipal wastewater on the degradation of 4 pharmaceutically active compounds (PhACs), including carbamazepine, clofibric acid, atenolol and erythromycin by the UV/H2O2 process were investigated. The results showed that the degradation rate constants of 4 PhACs decreased dramatically in the presence of DOM. The linear regressions of 4 PhACs degradation as a function of specific fluorescence intensity (SFI) are exhibited during the degradation of 4 PhACs and the SFI may be used to evaluate effect of DOM on target compounds in wastewater. The hydrophobic acid (HPO-A) exhibited the strongest inhibitory effect on degradation of 4 PhACs during oxidation process. The small MW fractions of DOM significantly inhibited the degradation of 4 PhACs during oxidation process. Among three fluorescence components, hydrophobic humic-like substances may significantly inhibit the degradation of 4 PhACs during oxidation process. At the molecular level, the formulas may be derived from terrestrial sources. CHO compound may significantly inhibit the degradation of 4 PhACs during oxidation process on formula classes. The unsaturated hydrocarbons, carbohydrates and tannins compounds may significantly inhibit the effectiveness of the UV/H2O2 process on compound classes.