TY - JOUR
T1 - Enhanced oxidative degradation of norfloxacin using peroxymonosulfate activated by oily sludge carbon-based nanoparticles CoFe2O4/OSC
AU - Liu, Biming
AU - Song, Wenbin
AU - Wu, Haixia
AU - Xu, Yanhua
AU - Sun, Yongjun
AU - Yu, Yang
AU - Zheng, Huaili
AU - Wan, Shipeng
N1 - Publisher Copyright:
© 2020 Elsevier B.V.
PY - 2020/11/15
Y1 - 2020/11/15
N2 - In this study, oily sludge (OS) was pyrolyzed into an environmentally friendly OS carbon (OSC) material, which was used as the carrier of CoFe2O4 nanoparticles to prepare a heterogeneous catalyst CoFe2O4/OSC, and it was used to catalyze the degradation of norfloxacin (NFC) by peroxymonosulfate (PMS). X-ray diffraction (XRD) and transmission electron microscope (TEM) characterization results show that CoFe2O4/OSC had a spinel structure under high temperature pyrolysis conditions. The effects of initial pH, PMS dosage, catalyst dosage, and temperature on NFC degradation efficiency were also studied. Under a temperature of 25 °C, an initial pH of 7, a catalyst amount of 0.5 g/L, and a PMS dosage of 0.8 mM, the reaction rate constant reached 0.051 min−1, and the degradation efficiency and total organic carbon of NFC reached 90.8% and 62%, respectively, within 60 min. Trace amounts of Co and Fe ions were leached from the system (both less than 30 μg/L). After ten cycles, the degradation efficiency of NFC decreased to 69.8%. Radical quenching experiments, electron paramagnetic resonance, and X-ray fluorescence spectroscopy characterization proved that free-radical ([rad]OH, SO4[rad]−, and O2[rad]−) and nonradical (1O2) active species were present in the system. Moreover, the CoFe2O4/OSC/PMS system involved the participation of two pairs of redox couples (Fe(II)/Fe(III) and Co(III)/Co(II)). Results from matrix-assisted laser desorption ionization time-of-flight mass spectrometry and ion chromatography proved that the main oxidation pathways of NFC were formed through the fragmentation of heterocycles, defluorination of benzene rings, decarboxylation reactions, and piperazine ring-opening process. At the same time, NFC was eventually oxidized to fluoride. This study provides potential for the resource utilization of OS and the application of sludge-type catalysts in PMS-activated oxidation systems.
AB - In this study, oily sludge (OS) was pyrolyzed into an environmentally friendly OS carbon (OSC) material, which was used as the carrier of CoFe2O4 nanoparticles to prepare a heterogeneous catalyst CoFe2O4/OSC, and it was used to catalyze the degradation of norfloxacin (NFC) by peroxymonosulfate (PMS). X-ray diffraction (XRD) and transmission electron microscope (TEM) characterization results show that CoFe2O4/OSC had a spinel structure under high temperature pyrolysis conditions. The effects of initial pH, PMS dosage, catalyst dosage, and temperature on NFC degradation efficiency were also studied. Under a temperature of 25 °C, an initial pH of 7, a catalyst amount of 0.5 g/L, and a PMS dosage of 0.8 mM, the reaction rate constant reached 0.051 min−1, and the degradation efficiency and total organic carbon of NFC reached 90.8% and 62%, respectively, within 60 min. Trace amounts of Co and Fe ions were leached from the system (both less than 30 μg/L). After ten cycles, the degradation efficiency of NFC decreased to 69.8%. Radical quenching experiments, electron paramagnetic resonance, and X-ray fluorescence spectroscopy characterization proved that free-radical ([rad]OH, SO4[rad]−, and O2[rad]−) and nonradical (1O2) active species were present in the system. Moreover, the CoFe2O4/OSC/PMS system involved the participation of two pairs of redox couples (Fe(II)/Fe(III) and Co(III)/Co(II)). Results from matrix-assisted laser desorption ionization time-of-flight mass spectrometry and ion chromatography proved that the main oxidation pathways of NFC were formed through the fragmentation of heterocycles, defluorination of benzene rings, decarboxylation reactions, and piperazine ring-opening process. At the same time, NFC was eventually oxidized to fluoride. This study provides potential for the resource utilization of OS and the application of sludge-type catalysts in PMS-activated oxidation systems.
KW - Norfloxacin degradation
KW - Oily sludge
KW - Peroxymonosulfate activation
KW - Resource utilization
UR - http://www.scopus.com/inward/record.url?scp=85086917540&partnerID=8YFLogxK
U2 - 10.1016/j.cej.2020.125947
DO - 10.1016/j.cej.2020.125947
M3 - 文章
AN - SCOPUS:85086917540
SN - 1385-8947
VL - 400
JO - Chemical Engineering Journal
JF - Chemical Engineering Journal
M1 - 125947
ER -