1,4-dioxane, commonly used as a solvent stabilizer and industrial solvent, is an environmental contaminant and probable carcinogen. In this study, we explored the concept of using metal oxides to activate H _(2) O _(2) catalytically at neutral pH in the dark for 1,4-dioxane degradation. Based on batch kinetics measurements, materials that displayed the most suitable characteristics (high 1,4-dioxane degradation activity and high H _(2) O _(2) consumption efficiency) were ZrO _(2) , WO _( x ) /ZrO _(2) , and CuO. In contrast, materials like TiO _(2) , WO _(3) , and aluminosilicate zeolite Y exhibited both low 1,4-dioxane degradation and H _(2) O _(2) consumption activities. Other materials ( e.g. , Fe _(2) O _(3) and CeO _(2) ) consumed H _(2) O _(2) rapidly, however 1,4-dioxane degradation was negligible. The supported metal oxide WO _( x ) /ZrO _(2) was the most active for 1,4-dioxane degradation and had higher H _(2) O _(2) consumption efficiency compared to ZrO _(2) . In situ acetonitrile poisoning and FTIR spectroscopy results indicate different surface acid sites for 1,4-dioxane and H _(2) O _(2) adsorption and reaction. Electron paramagnetic resonance measurements indicate that H _(2) O _(2) forms hydroxyl radicals (˙OH) in the presence of CuO, and unusually, forms superoxide/peroxyl radicals (˙O _(2) ~(?) ) in the presence of WO _( x ) /ZrO _(2) . The identified material properties suggest metal oxides/H _(2) O _(2) as a potential advanced oxidation process in the treatment of 1,4-dioxane and other recalcitrant organic compounds.
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