Abstract: A method of degrading 1,4-dioxane in the wastewater produced during the manufacture of alkyl ether sulfates is disclosed. The method includes the steps of (a) mixing from 100 to 10,000 ppm, preferably 1,000 to 4,000 ppm of ozone with the wastewater; (b) introducing H2O2 into the wastewater in an amount of 0.01 to 10, preferably 0.1 to 0.5 molar equivalents of H2O2 to ozone, and (c) mixing the ozone, H2O2, and wastewater to generate hydroxyl radicals reactive with the 1,4-dioxane, without the addition of a metal catalyst. The hydroxyl radicals react with the 1,4-dioxane and degrade it into carbon dioxide, water and/or carbonate. The method is effective to reduce a concentration of 1,4-dioxane in the wastewater from a range of about 10 ppm to about 1000 ppm of dioxane down to less than 5 ppb of 1,4-dioxane after treatment. The method is also effective for removing hydrocarbon species that may be present in the wastewater.

Abstract: A method of degrading 1,4-dioxane in the wastewater produced during the manufacture of alkyl ether sulfates is disclosed. The method includes the steps of (a) mixing from 100 to 10,000 ppm, preferably 1,000 to 4,000 ppm of ozone with the wastewater; (b) introducing H2O2 into the wastewater in an amount of 0.01 to 10, preferably 0.1 to 0.5 molar equivalents of H2O2 to ozone, and (c) mixing the ozone, H2O2, and wastewater to generate hydroxyl radicals reactive with the 1,4-dioxane, without the addition of a metal catalyst. The hydroxyl radicals react with the 1,4-dioxane and degrade it into carbon dioxide, water and/or carbonate. The method is effective to reduce a concentration of 1,4-dioxane in the wastewater from a range of about 10 ppm to about 1000 ppm of dioxane down to less than 5 ppb of 1,4-dioxane after treatment. The method is also effective for removing hydrocarbon species that may be present in the wastewater.

Abstract: Oxidizable contaminants in water are destroyed rapidly and efficiently by exposing the water to oxidizing conditions under pressure. Specifically, a single dose of hydrogen peroxide may be injected into the water, followed by the repeated injection and mixing of low doses of ozone. In each such high intensity mixing/reaction stage, ozone is injected at a pressure, velocity, and direction approximately matching that of the contaminated water flow. High intensity mixing under pressure facilitates rapid and complete oxidation of the contaminants with minimal stripping of volatile contaminants and waste of undissolved ozone. Residual ozone levels after high intensity mixing may be carefully monitored and minimized by adjusting the injection of hydrogen peroxide and ozone in order to suppress the formation of bromate. Additional contaminants may be removed by passing the treated water through activated carbon beds.