Activation of ozone by peroxymonosulfate for selective degradation of 1,4-dioxane: Limited water matrices effects

The presence of 1,4-dioxane in various water streams poses a threat to the health of human beings. In this study, the oxidative combination of ozone with peroxymonosulfate (PMS) was for the first time used to remove 1,4dioxane from water. Near complete abatement of 1,4-dioxane was achieved by ozone-PMS after reaction of only 15 min and the degradation kinetics was found to be positively correlated with doses of PMS and ozone. Ozone-PMS oxidation had the optimum performance at slight base pH values. Both sulfate radicals and hydroxyl radicals were generated in ozone-PMS oxidation and these radicals resulted in the degradation of 1,4-dioxane. The effects of common water constituents and real water matrices were investigated. It was found that bicarbonate ions with a concentration up to 10 mM had a slight promoting effect, while either chloride ions or natural organic matter inhibited only slightly the degradation. Meanwhile, no obvious difference in the degradation of 1,4-dioxane was found among the real water matrices and deionized water, which demonstrates that ozone-PMS oxidation has high tolerance and stability. The results from this study demonstrate that ozone-PMS may be a promising technology for the removal of 1,4-dioxane from various water matrices.

Automated summary

In this study, the combination of ozone and peroxymonosulfate (PMS) was used for the first time to remove 1,4-dioxane from water, achieving near complete degradation within 15 minutes. The degradation process was found to be positively correlated with the doses of PMS and ozone, and showed optimum performance at slight base pH values. The oxidation generated sulfate and hydroxyl radicals that contributed to the degradation of 1,4-dioxane.