Abstract: In this paper, SO-4· was activated by peroxydisulfate(PDS) with zero-valent iron(Fe0) in aqueous, and its activity was tested by removing atrazine. Influencing factors including the initial pH, initial concentration of PDS and dosage of Fe0 were tested. The results indicated that removal efficiencies of atrazine(100 mL 0.10 mmol/L) by Fe0/PDS reached 99.0% within 60 min at pH=6.5, 1 mL PDS initial concertration 2.0 mmol/L, 28 mg Fe0, which was much higher than that when Fe0 or PDS was used alone, and superior to the Fe2+/PDS or Fe3+/PDS with the same amount of iron. Results also showed that the oxidation process of atrazine by SO-4· was facilitated by lowering pH, and the removal efficiency increased with raising the initial concentration of PDS or iron dosage. In addition, the reactive intermediates were identified as SO-4· and hydroxyl radicals(·OH) by employing methanol(MeOH) and tert-butyl alcohol(TBA) as the radical quenching agents.

Key words: zero-valent iron, peroxydisulfate, sulfate radicals, atrazine