In this study, we develop a new strategy for dechlorination of atrazine using hydrogen peroxide (H2O2) at pH ≥ 11.0 without addition of any other reagents at room temperature. Scavenging experiments, isotope experiments, theoretical calculation, and high resolution mass spectra reveal that the hydroperoxide anion (HO2 –), the product of deprotonation of H2O2, can induce dechlorination of atrazine to form triazinyl hydroperoxide (C8H14N5OOH) via nucleophilic substitution. Subsequently, the as-obtained C8H14N5OOH reacts with reductive HO2 – to generate C8H14N5OOOH. Finally, hydroxyatrazine (C8H14N5OH) is generated through intramolecular redox decomposition of C8H14N5OOOH. Even though atrazine cannot be completely mineralized by this method, this H2O2-induced dechlorination of atrazine can greatly decrease their biological toxicity. In addition, the alkaline H2O2 system also achieves outstanding performance in dechlorination of other typical chlorotriazine herbicides such as simazine, propazine, and terbutylazine. The typical coexisted ions of Cl– and NH4 + show negligible effect on degradation of these chlorotriazine herbicides. This study will have an important implication on the potential application of alkali-H2O2 for treatment of chlorotriazines manufacturing wastewater.

No abstract

No abstract

No abstract