Determination of optimum operational conditions for the removal of 2-MIB from drinking water by peroxone process: A pilot-scale study

Taste and odor in drinking water are one of the main problems of the water supply and treatment sector. Peroxone is an effective advanced oxidation process, which combines ozone with hydrogen peroxide to create hydroxyl radicals that decompose organic compounds. 2-Methylisoborneol (2-MIB) is one of the significant taste and odor causing compounds, which can be removed with the peroxone process. In this study, removal of a 2-MIB compound by peroxone process was investigated in a pilot-scale treatment plant and optimum operational conditions were determined. For safety reasons, it is important that residual O₃ and H₂O₂ concentrations in the water leaving the reactor should not exceed 0.1 and 0.5 mg/L, respectively. Results indicate that while dissolved ozone concentration was below the indicated limit for all experiments, concentrations over 0.5 mg/L residual H₂O₂ were observed during the experiments with an H₂O₂:O₃ ratio of 0.5. This limit exceedance affected the decision on the ideal peroxone ratio along with the 2-MIB removal results. Therefore; optimum H₂O₂:O₃ ratio was determined as 0.3. 2-MIB removal efficiency of 81% was achieved at the optimum H₂O₂:O₃ ratio with a contact time of 15 min. According to the results, 2-MIB removal rate had a linear correlation with the contact time.