The catalytic performances of catalysts were investigated by activating PMS for TCH degradation. Tetracycline hydrochloride (TCH) is a typical representative of tetracycline antibiotics. In this paper, Fe–Co bimetal-modified FeCo-ZSM-5 catalysts were efficiently prepared by the equal volume impregnation method (40) and characterized. Furthermore, the deeper synergetic mechanism is still unclear and needs to be revealed. (29) However, there are few reports on the application of Fe–Co bimetal-modified ZSM-5 zeolites for wastewater treatment. The synergistic effect of Fe and Co made the catalytic reaction more efficient. (20) For example, it has been reported that iron-cobalt layered double hydroxide can be synthesized to activate PMS to degrade tetracycline. Co is a good candidate, whose catalytic activity is higher than single-metal catalysts. (28) To further improve the activity of iron-based catalysts, it is feasible to add another metal. (26,27) Nonetheless, the poor stability and low transformation efficiency of Fe 3+/Fe 2+ inhibit the catalytic activity for PMS activation. (22−25) With the advantage of low cost and environment friendliness, iron species is an appealing candidate to be doped into the ZSM-5 zeolite. ![]() (21) In the past few years, ZSM-5 zeolite has been intensively employed as the support for constructing highly efficient catalysts because of its high activity, uniform pore structure, excellent hydrothermal stability, and efficient cation exchange ability. (19,20)Īluminosilicate zeolites are regarded as one of the best supports due to its high surface areas and excellent stability. (18) Therefore, functional transition metal atoms have been introduced into the zeolite framework to increase the dispersion of catalytically active sites. (16,17) Furthermore, studies have shown that the good dispersion of transition metals on supports can improve the efficiency of catalyst activation of PMS. There are many reports that activated PMS can effectively degrade tetracycline antibiotics. Transition metals (Fe, Co, Cu, and Mn) can activate PMS at room temperature and pressure without additional energy. (15) Besides, PMS can be activated by many methods, such as thermal activation and UV activation but they incur high cost and consume more energy. (10,11) Therefore, PMS has been extensively studied in real industrial wastewater, such as landfill leachate, (12) petrochemical wastewater, (13) pharmaceutical wastewater, (14) and pulp and paper wastewater. –), which have the advantages of a wide range of pH, a high oxidation potential, a long half-life time, and biodegradability.(9) AOPs based on peroxymonosulfate (PMS) can activate and generate sulfate radicals (SO 4 OH is always limited by strict pH requirements.(7,8) The practical application of Fenton system based on This work provides certain guiding significance in understanding the synergistic effect of heterogeneous catalysts for tetracycline wastewater treatment.Īdvanced oxidation processes (AOPs) are efficient ways for oxidizing and degrading PPCPs. Furthermore, liquid chromatography–mass spectrometry was conducted to propose possible degradation pathways. Electron paramagnetic resonance spectra and quenching experiments showed that sulfate radicals, singlet oxygen, and hydroxyl radicals were involved in the degradation of TCH. ![]() The Fe–Co bimetallic doping increased the area of positive potential mapped to the electron cloud and benefited the adsorption of PMS on the catalyst surface, which revealed the synergistic mechanism of bimetals. Density functional theory calculations indicated that Co was the main active site for PMS adsorption, and Fe increased the area of Co’s positive potential mapped to the electron cloud. In addition, the influences of catalyst dosage, PMS concentration, reaction temperature, initial pH, and coexisting ions on TCH removal were systematically investigated in this paper. The tetracycline hydrochloride (TCH) degradation experiments showed that the catalytic activity of FeCo-ZSM-5-2:3 was much higher than those of Fe-ZSM-5 and Co-ZSM-5. In this paper, the synergistic mechanism of enhanced PMS activation was revealed by constructing iron and cobalt bimetal modified ZSM-5 zeolite catalysts (FeCo-ZSM-5). However, few studies have unveiled the clear synergistic mechanism of iron and cobalt in ZSM-5. Iron- and cobalt-based heterogeneous catalysts are widely applied for activating peroxymonosulfate (PMS) to degrade organic pollutants.
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