UV‐Activated Advanced Oxidation of MTBE and TBA: A Comparison of Sulfate and Hydroxyl‐Radical Treatment Processes

Contaminated groundwater must be treated to protect drinking water supplies. This study investigated the degradation of MTBE and TBA with UV/persulfate (PS) and UV/hydrogen peroxide (H₂O₂) advanced oxidation processes. Experiments were conducted at initial concentrations of MTBE and TBA of 7.4 and 6.2 mg/L respectively over a range of conditions and computational analysis was carried out to elucidate reaction mechanisms and pathways. Pseudo first-order rate constants were retrieved from temporal degradation profiles. MTBE degradation was faster than that of TBA, and UV/PS-driven oxidation of both chemicals was faster than that of UV/H₂O₂. Relative absorptivity measurements showed that PS absorbed a higher proportion of light than H₂O₂ did, which in turn created greater potential to generate radicals. Density Functional Theory (DFT) results provided additional new insights. UV/PS is a promising groundwater remediation technology for the removal of MTBE and TBA.