Abstract Quinoline inevitably remains in the effluent of coking wastewater treatment plants due to its bio-refractory nature, which might cause unfavorable effects on human and ecological environments. In this study, MnCexOy was consciously synthesized by α-MnO2 doped with Ce3+ (Ce:Mn = 1:10) and employed as the ozonation catalyst for quinoline degradation. After that, the removal efficiency and mechanism of quinoline were systematically analyzed by characterizing the physicochemical properties of MnCexOy, investigating free radicals and monitoring the solution pH. Results indicated that the removal rate of quinoline was greatly improved by the prepared MnCexOy catalyst. Specifically, the removal efficiencies of quinoline could be 93.73, 62.57 and 43.76%, corresponding to MnCexOy, α-MnO2 and single ozonation systems, respectively. The radical scavenging tests demonstrated that •OH and •O2- were the dominant reactive oxygen species in the MnCexOy ozonation system. Meanwhile, the contribution levels of •OH and •O2- to quinoline degradation were about 42 and 35%, respectively. The abundant surface hydroxyl groups and oxygen vacancies of the MnCexOy catalyst were two important factors for decomposing molecular O3 into more •OH and •O2-. This study could provide scientific support for the application of the MnCexOy/O3 system in degrading quinoline in bio-treated coking wastewater.

中文翻译：

---

MnCexOy 催化剂催化臭氧化有效降解喹啉：性能和机理

摘要喹啉由于其生物难降解性，不可避免地残留在焦化废水处理厂的废水中，这可能对人类和生态环境造成不利影响。本研究通过掺杂Ce3+（Ce:Mn=1:10）的α-MnO2有意识地合成了MnCexOy，并将其用作喹啉降解的臭氧化催化剂。之后，通过表征MnCexOy的理化性质、研究自由基和监测溶液pH值，系统分析了喹啉的去除效率和机理。结果表明，所制备的MnCexOy催化剂大大提高了喹啉的去除率。具体而言，喹啉的去除效率分别为93.73%、62.57%和43.76%，分别对应于MnCexOy、α-MnO2和单一臭氧化系统。自由基清除测试表明·OH和·O2-是MnCexOy臭氧化系统中主要的活性氧物种。同时，·OH和·O2-对喹啉降解的贡献水平分别约为42%和35%。 MnCexOy催化剂丰富的表面羟基和氧空位是O3分子分解成更多·OH和·O2-的两个重要因素。该研究可为MnCexOy/O3体系降解生物处理焦化废水中喹啉的应用提供科学支持。