Degradation of AO7 by PMS activated by FeOCl

FeOCl was prepared by the partial thermal decomposition method, and then used to activate PMS to degrade refractory azo dye AO7. The synthesized FeOCl was characterized by XPS, SEM and XRD. The degradation of AO7 was evaluated in the FeOCl/PMS system, and various factors affecting the removal rate of AO7 was investigated. The results showed that AO7 was rapidly degraded in the FeOCl/PMS system, and mineralization rate has reached to 44%. AO7 could be completely degraded in 30min at neutral condition with 50mg/L FeOCl, 1.0mmol/L PMS and 0.05mmol/L AO7. The decolorization of AO7 increased with the increase of PMS concentration, FeOCl dosage, Cl- concentration and the initial pH. FeOCl also exhibited a fine reusability. The main active species and reaction mechanism were verified by the radical quenching experiment, EPR test and XPS analysis. The SO4-•and •OH produced by the activation of PMS contributed to the degradation of pollutants, and SO4-•played the dominant role. © 2020, Editorial Board of China Environmental Science. All right reserved.