锰基氧化物活化过硫酸盐降解水中有机污染物的研究进展

In recent years, development of novel sulfate radical-based advanced oxidation processes and their application in water pollution control and soil remediation have attracted much attention. Mn-based oxides are widely used as an effective catalyst for the degradation of organic contaminants by activation of peroxymonosulfate (PMS) and peroxydisulfate (PDS) due to their structural diversity, natural abundance, environmental friendliness and other advantages. This review comprehensively elucidates the types, structural characteristics, synthesis methods and factors affecting reactivity of various Mn-based materials which are used to activate PMS/PDS, with a special focus on the activation mechanisms of various Mn-based catalysts. The future research and development on this topic are prospected, aiming to provide an important reference for expanding the environmental application of manganese-based mineral materials and elucidating the activation mechanism of persulfate. It is found that the sulfate radicals and hydroxyl radicals produced by activation play a key role in the degradation of pollutants. In particular, sulfate radicals have high stability and oxidability, and play a leading role in the degradation process. The composite Mn-based oxide exhibits better catalytic reaction activity than a single Mn-based oxide. There are different reaction mechanisms for MnO₂ to activate PMS and PDS. The former generates SO₅•^- and SO₄•^- through redox reactions between Mn(Ⅳ) and Mn(Ⅲ), while the latter generates S₂O₈•^- and SO₄•^-. In addition, MnO₂ activated PDS also has a non-radical reaction mechanism that only generates singlet oxygen. At present, the related research on PDS activation by Mn-based oxides is still scarce, deserving further investigations in future. More direct experimental evidence is needed for the identification of the active intermediate Mn(Ⅲ) produced by Mn-based materials activated PDS/PMS and evaluation of its contribution to the degradation of pollutants.