In this study, the COD and TOC in H2O2-HCO3– oxidation system containing potassium hydrogen phthalate were determined by UV spectrophotometry (260-310 nm). The pH and H2O2 concentrations were investigated as factors influencing the absorbance measurements. The obtained standard curves were Abs = (3.10±0.04)x103xCOD - (0.015±0.003) (R2=0.9996) with LOD of 5.1 mg O2/l and LOQ of 13.6 mg O2/l, and Abs = (0.008±0.0001)xTOC - (0.015±0.003) (R2=0.9996) with LOD of 1.6 mg/l and LOQ of 5.4 mg/l. The method was applied to monitor the degradation of potassium hydrogen phthalate by the H2O2-HCO3– oxidation system. The results revealed that the COD and TOC removal efficiencies reached ~85% after 90 minutes of UVC irradiation. The UV spectra and HPLC chromatographs showed that no aromatic compounds were obtained in the degradation products.
COD, TOC determination using UV spectrophotometry and its application to monitor the potassium hydrogen phthalate degradation by H2O2-HCO3– oxidation system
