Various earth-rich transition metal elements such as iron and manganese have been applied to activate sulfite for the degradation of pollutants. However, the redox process of manganese and its role in pollutants removal in the Mn(II)/sulfite system remain unclear. Batch experiment was performed in this study to investigate the manganese oxidation mechanisms and triclosan (TCS) degradation in a mixture solution with Mn(II) and sulfite under aerobic conditions. About 75 % removal of TCS was achieved in the Mn(II)/sulfite (200 μM/200 μM) system at pH 6.0 within 24 h aerobic reaction, and the conversion efficiency was positively related to the concentrations of Mn(II). The addition of Mn(II) led to the rapid depletion of sulfite within the initial two minutes and the rod-shaped MnO₂ was obviously generated in the subsequent reaction accompanied by the degradation of TCS. Quenching experiments revealed that manganese oxide, rather than sulfur radicals, was the major reactive oxidant for TCS degradation, and SO₅^•- and SO₄^•- were responsible for the formation of manganese oxide, directly verified by ABTS method and X-ray photoelectron spectroscopy (XPS) analysis. In addition, TCS oligomers (dimers and trimers) were mainly produced through a single electron process between manganese oxide and TCS. The results of this study proved the in-situ formation of active manganese oxide in Mn(II)/sulfite system under aerobic condition, which could induce the transformation of organic contaminants.

各种富含地球的过渡金属元素如铁和锰已被用于活化亚硫酸盐以降解污染物。然而，锰的氧化还原过程及其在 Mn(II)/亚硫酸盐体系中去除污染物中的作用仍不清楚。本研究通过批量实验研究了Mn(II) 和亚硫酸盐混合溶液在好氧条件下的锰氧化机理和三氯生(TCS) 降解。在 Mn(II)/亚硫酸盐 (200 μM/200 μM) 体系中，在 pH 6.0 的 24 h 好氧反应中，TCS 的去除率约为 75%，且转化效率与 Mn(II) 浓度呈正相关。添加 Mn(II) 导致亚硫酸盐在最初两分钟内迅速耗尽，棒状 MnO ₂在随后的反应中明显产生伴随着 TCS 的降解。淬火实验表明，氧化锰，而不是硫自由基，是TCS降解的主要活性氧化剂，SO ₅ ^•-和SO ₄ ^•-是氧化锰形成的原因，通过ABTS法和X射线光电子直接验证光谱（XPS）分析。此外，TCS 低聚物（二聚体和三聚体）主要通过氧化锰和 TCS 之间的单电子过程产生。本研究结果证明，在好氧条件下，Mn(II)/亚硫酸盐体系中原位形成活性氧化锰，可诱导有机污染物的转化。