摘要
针对污水处理厂的出水中检测出了未代谢药物、内分泌干扰物等生物难降解有机物的问题,通过制备Mn/Fe双金属氧化物催化剂MnFeO,并耦合过一硫酸盐(PMS)构建了基于PMS活化的高级氧化体系,以降解废水中的BPA。结果表明,由于活化位点丰度的提升,所构建体系的氧化性能随着催化剂投加量的增加而增加;过高的PMS浓度会触发体系的自淬灭效应,从而导致污染物降解性能降低;该体系在不同pH条件下均表现出了良好的污染物降解性能,由于PMS稳定性的变化,弱碱性环境可显著提升体系的氧化性能。催化剂在循环使用过程中的催化性能有明显衰减,但可通过在空气气氛中的煅烧实现性能恢复。顺磁共振分析和自由基淬灭实验结果表明,体系中产生的自由基与单线态氧是PMS分解形成的主要活性物种;而电化学分析结果表明,污染物与MnFeO-PMS复合体之间存在直接电子传递过程,通过活性物种与直接电子传递过程实现了有机污染物的降解。以上研究结果可为锰铁双金属氧化物活化PMS提供参考。
In order to remove the metabolized drugs,endocrine disruptors and some other bio-refractory organic compounds in the effluent of the sewage treatment plant,a Mn/Fe bimetallic oxide(MnFeO)was synthesized to activate peroxymonosulfate(PMS)for the degradation of bisphenol A(BPA).The results showed that the increased catalysts dosage could effectively elevate the BPA degradation efficiency.Excessive addition of PMS would decrease the BPA degradation due to the radical quenching effect caused by PMS.MnFeO/PMS exhibited BPA degradation performance in a wide pH range,where slight basic condition would enhance the BPA degradation performance due to the instability of PMS at basic solution.The activation performance of MnFeO slightly decreased with the consecutively runs,which could be effectively recovered through the calcination of the used MnFeO in air at 450℃.EPR analysis and quench experiment proved the generation of radicals and singlet oxygen involved in the reaction.It was further revealed that direct electron-transfer from BPA to MnFeO/PMS also contributed to the degradation of BPA.The results of this study provided sufficient information for the Mn/Fe bimetallic oxide activated PMS system.
作者
李广英
杜敏洁
谈成英
关海刚
陈荣志
LI Guangying;DU Minjie;TAN Chengying;GUAN Haigang;CHEN Rongzhi(Qinghai ecological environment planning and environmental protection technology center,Xining 810007,China;College of Resources and Environment,University of Chinese Academy of Sciences,Beijing 100049,China)
出处
《环境工程学报》
CAS
CSCD
北大核心
2021年第9期2952-2962,共11页
Chinese Journal of Environmental Engineering
基金
青海省重大科技专项(2018-SF-A4)
