Caihong Liu,Xihui Jiang,Zhiqiang Sun,Rui Gao,Min Wang,Qiang He,Jun Ma
Catalytic membranes that enable simultaneous micropollutant degradation during oil/water separation have emerged as a promising candidate for treating complex emulsified oily wastewater. However, this hybrid system suffers from membrane fouling and subsequent radical quenching. Herein, we overcome these challenges by developing a novel hierarchical filtration-catalysis ceramic membrane to achieve efficient gradient decontamination. This membrane comprises a top hydrophilic MWCNT layer deposited on a CuFe2O4-immobilized ceramic membrane to construct CCuFeCM. A pristine ceramic membrane (CM) and a CuFe2O4-immobilized membrane (CuFeCM) served as controls. Our results demonstrated that CCuFeCM presents the most alleviated fouling potential (∼18% of flux decline) and TOC removal (91%) when treating synthetic textile wastewater containing a mineral oil-in-water emulsion with RhB. Besides that, CCuFeCM achieves the highest PMS-based RhB degradation capability (100%) and initial reaction rate (0.684 min–1). Quenching experiments and EPR analyses show that SO4–•, •OH, and 1O2 are responsible for the CCuFeCM/PMS oxidation system, and 1O2 is the dominant reactive species. The synergistic effect of oil separation and catalytic decomposition is mainly ascribed to the ordered arrangement of selective separation in advance to avoid interference with subsequent AOPs, which allows for micropollutants that are transmitted into internal membrane channels for confined catalytic oxidation. Furthermore, replication filtration tests indicate that CCuFeCM shows durable stable degradation and antifouling performance after simple cleaning. The specific functionality of oil isolation, catalyst anchor, and mass transfer effect reaction compartmentation provides a novel strategy for efficient gradient removal of multiple pollutants in water, which highlights promising application potential under realistic conditions.
The Advanced Oxidation Processes (AOPs) still require further research in response to ever-increasing standard of reclaimed water reuse and operating environment requirements. In this study, an efficient microwave-ultraviolet catalyzed oxidation system (MW-UV) was successfully developed, and its degradation effect was studied by using activated H 2 O 2 , sodium percarbonate (SPC), persulfate (PS), and peroxymonosulfate (PMS) to degrade toxic organic contaminants in wastewater and actual industrial wastewater. It was shown that MW-UV had an exceptionally high capability to react with these four common peroxides to produce reactive radicals ( OH and SO 4 − ). This can destroy multiple toxic organic contaminants through nonselective oxidation with a wide range of pH applications, has strong adaptability to anions in bodies of water, and can effectively treat wastewater. The sequence of predominant free radical generation rate by MW-UV was SPC > H 2 O 2 > PS > PMS, with higher generation rate constant than other Fenton processes. The free radical evolution mechanisms for H 2 O 2 , SPC, PS, and PMS activation were also investigated. The thermal and non-thermal effects of microwave irradiation have a significant enhancement for UV reactions, and thus the synergy between the MW and UV can effectively activate peroxide. This treatment method could provide scientific basis and reference for degrading toxic organic contaminants in small-scale and limited space wastewater treatment.
危险品化学品经营许可证（带存储）