School of Environment and Municipal Engineering, Lanzhou Jiaotong University, 88 Anningxi Road, Anning District, Lanzhou City, Gansu Province 730070, China; School of Civil Engineering, Lanzhou University of Technology, 287 Langongping Road, Qilihe District, Lanzhou City, Gansu Province 730050, China E-mail:
CSCEC AECOM CONSULTANTS CO., LTD, 459 Dingxi Road, Chengguan District, Lanzhou City, Gansu Province 730030, China.
Water Sci Technol. 2023 Oct;88(8):2174-2188. doi: 10.2166/wst.2023.326.
Four kinds of manganese oxides were successfully prepared by hydrothermal and redox precipitation methods, and the obtained oxides were used for CIP removal from water by activating PMS. The microstructure and surface properties of four oxides were systematically characterized. The results showed that ε-MnO prepared by the redox precipitation method had large surface area, low crystallinity, high surface Mn(III)/Mn(Ⅳ) ratio and the highest activation efficiency for PMS, that is, when the concentration of PMS was 0.6 g/L, 0.2 g/L ε-MnO could degrade 93% of CIP within 30 min. Multiple active oxygen species, such as sulfate radical, hydroxyl radical and singlet oxygen, were found in CIP degradation, among which sulfate radical was the most important one. The degradation reaction mainly occurred on the surface of the catalyst, and the surface hydroxyl group played an important role in the degradation. The catalyst could be regenerated in situ through the redox reaction between Mn and Mn. The ε-MnO had the advantages of simple preparation, good stability and excellent performance, which provided the potential for developing new green antibiotic removal technology.
四种锰氧化物通过水热和氧化还原沉淀法成功制备，并用所得氧化物通过活化过一硫酸盐（PMS）去除水中的 CIP。系统地表征了四种氧化物的微观结构和表面特性。结果表明，通过氧化还原沉淀法制备的 ε-MnO 具有较大的表面积、较低的结晶度、较高的表面 Mn(III)/Mn(Ⅳ)比和对 PMS 的最高活化效率，即当 PMS 浓度为 0.6 g/L 时，0.2 g/L 的 ε-MnO 可在 30 min 内降解 93%的 CIP。在 CIP 降解过程中发现了多种活性氧物质，如硫酸根自由基、羟基自由基和单线态氧，其中硫酸根自由基是最重要的一种。降解反应主要发生在催化剂表面，表面羟基在降解中起重要作用。催化剂可以通过 Mn 和 Mn 之间的氧化还原反应在原位再生。ε-MnO 具有制备简单、稳定性好、性能优异的优点，为开发新型绿色抗生素去除技术提供了潜力。
