Activation of Peroxymonosulfate by Phosphate and Carbonate for the Abatement of Atrazine: Roles of Radical and Nonradical Species

• DOI: 10.1021/acsestwater.1c00482
• Publication Date: 2022-03-29T18:49:12Z
• Authors: Yinghao Wen; Virender K. Sharma; Xingmao Ma
• Keywords: Hydroxyl radical; Perchlorate

While the activation mechanisms of peroxymonosulfate (PMS) by various homogeneous and heterogeneous catalysts have been reported, chemistry PMS in a catalyst-free system its interactions with background oxyanions are still poorly understood. This paper demonstrated two prevalent (phosphate carbonate) revealed for enhanced atrazine (ATZ) degradation at neutral pH. Both activated to produce sulfate radical (SO4•–), which reacts ATZ rapidly, but phosphate exhibited stronger effect than carbonate. The reaction between SO4•– produced other possible radicals presence dissolved oxygen (e.g., ATZ–O–O•), subsequently generated singlet (1O2) superoxide (O2•–) as precursor. However, their contributions were minimal. formation species PMS–ATZ–phosphate was supported selective quenching electron paramagnetic resonance measurements under different conditions [oxic, anoxic, solvents (H2O D2O)]. Direct oxidation also observed. Overall, direct accounted 75–78% 22–25% degradation, respectively.