Abstract

Versatile catalytic oxidation filtration system, especially under low operating pressure conditions, is a frontier technology for organic wastewater purification. Herein, CoTiO3/TiO2 heterostructure was anchored on fiber network (CTO/TOF) to actuate flow-through peroxymonosulfate (PMS) based oxidation toward organics removal. The well-developed built-in electric field in CoTiO3/TiO2 heterostructure induced local charge redistribution, and promoted the targeted adsorption and activation of PMS, thereby facilitating the activation process. Meanwhile, the 3D network of CTO/TOF fully exposes active sites, providing an ideal platform for mass transfer and surface reactions. Above 91% for nimesulide degradation was maintained after 24 h of catalytic permeation under high permeate flux (300.7 L/m2 & sdot;h), corresponding to ultrafast retention time (4.9 s). Practical application experiments demonstrated that CTO/TOF+PMS system had strong anti-interference capability under diverse conditions. Synergy of radical-nonradical mixed pathways for pollutant removal was verified by electron paramagnetic resonance spectra, quenching tests, and electrochemical measurements. The degradation intermediates and possible degradation pathways of nimesulide were also proposed. The toxicity assessments confirmed decreased toxicity of degradation products. This study is dedicated to designing high-performance filters and broadening Fenton-like oxidation in environmental remediation.

Details