摘要：

2-Mercaptobenzothiazole (MBT) has been detected in wastewater and surface water in recent years, and its re-moval by minerals is an important issue. In this study, the degradation of MBT by different manganese dioxides was investigated with batch experiments. The physicochemical properties, including specific surface area (BET), average oxidation state (AOS), reduction potential (Eh), and point of zero charge (pH PZC) of the manganese dioxides, were also evaluated. The results showed that MBT can be effi-ciently degraded within four minutes. More importantly, the oxidative activities of different manganese dioxides were influenced by a combination of factors including BET, Eh, AOS, and pH pzc . Manganese dioxides synthesized by the comproportionation method (CM) or liquid-phase oxidation method (OM) exhibited oxidative activities for MBT degradation with the order of δ-MnO 2 (CM) > α-MnO 2 (CM) > α-MnO 2 (OM) > γ-MnO 2 (OM) > β-MnO 2 (OM). The degradation kinetics based on MBT initial con-centration, manganese dioxide dosages and pH values were also evaluated. Lower initial MBT concentration and pH, and higher manganese dioxide dosages can accelerate the degradation rate. The thermodynamical results showed that the apparent activation energy (E a) was negatively corre-lated with MBT degradation rates. The results in this study may provide penetrated insights for understanding the transformation and fate of organic pollutants with the presence of manganese dioxides in environment.

展开