Open AccessFacile synthesis of magnetic ZnFe2O4/AC composite to activate peroxydisulfate for dye degradation under visible light irradiation
Author(s) -
Tingting Song,
Quanbao He,
Xiaoyan Meng,
Zhangxing He,
Ming Ge
Publication year - 2022
Publication title -
environmental science and pollution research international
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.845
H-Index - 113
eISSN - 1614-7499
pISSN - 0944-1344
DOI - 10.1007/s11356-022-21253-3
Subject(s) - peroxydisulfate , degradation (telecommunications) , composite number , irradiation , visible spectrum , chemistry , ecotoxicology , materials science , nuclear chemistry , photochemistry , environmental chemistry , optoelectronics , composite material , catalysis , physics , biochemistry , computer science , telecommunications , nuclear physics
Heterogeneous photocatalysis/persulfate oxidation process has been considered as a promising technology for dye contaminants removal. The magnetic ZnFe 2 O 4 /active carbon (AC) composites were hydrothermally synthesized and firstly used to activate peroxydisulfate (PDS) for rhodamine B (RhB) degradation under visible LED light irradiation. The optimized Vis-ZnFe 2 O 4 /AC(4/1)-PDS system can enhance the RhB degradation efficiency by 32.01% and 13.87% compared with Vis-ZnFe 2 O 4 -PDS and Vis-AC-PDS systems, respectively. The influence of operational parameters such as catalyst dosage (0.2 - 0.4 g L -1 ), PDS concentration (1.0 - 2.0 g L -1 ), temperature (25 - 45 °C), solution pH (2.7 - 10.9), and coexisting inorganic ions (Cl - , NO 3 - , HCO 3 - , PO 4 3- , Cu 2+ , Fe 3+ , and Ca 2+ ) on RhB degradation was studied, and 100% of RhB (20 mg L -1 ) was degraded after 80 min at operational condition: 0.30 g L -1 of ZnFe 2 O 4 /AC(4/1) and 1.5 g L -1 of PDS, solution pH of 2.74, reaction temperature of 25 °C. The quenching experiments, EPR test, and XPS analysis were employed to reveal the proposed mechanism, which demonstrated that 1 O 2 played a more important role than other reactive species (SO 4 •- , •OH, O 2 •- , and h + ) in RhB degradation. The generation of 1 O 2 via the two routes was as follows: (i) the in situ formed active oxygen (O * ) reacted with HSO 5 - to produce 1 O 2 ; (ii) O 2 •- was oxidized by h + to form 1 O 2 . After five consecutive cycles, the photodegradation efficiency of RhB by ZnFe 2 O 4 /AC(4/1) catalyst slightly decreased from 88.52 to 83.92%, indicating the excellent reusability of ZnFe 2 O 4 /AC(4/1) photocatalyst. As designed, Vis-ZnFe 2 O 4 /AC-PDS oxidation system can effectively remove RhB from the different real water matrices, and the degradation efficiency of RhB in tap water, river water, and secondary effluent was 78.24%, 79.55%, and 74.53% after 80 min of reaction, respectively.