The removal of tetracycline with biogenic CeO2 nanoparticles in combination with US/PMS process from aqueous solutions: kinetics and mechanism

Abstract

Antibiotics have received great attention because of their abuse and potential hazards to the human health and environment. In the current work, peroxymonosulfate (PMS) was added to a cerium oxide (CeO2)/ultrasonic (US) system for tetracycline (TC) degradation. CeO2 nanoparticles (NPs) were synthesized by a simple and cost-effective method using Stevia rebaudiana leaf extract and cerium nitrate as precursors. The as-synthesized CeO2 NPs were characterized by X-ray diffraction, field emission scanning electron microscopy, and Fourier-transform infrared spectroscopy analysis. The effects of catalyst dosage, PMS concentration, US power, initial antibiotic concentration, and pH on TC removal were investigated. The results confirmed the formation of CeO2 NPs with a fluorite structure, spherical shape, and average particle size of 29 nm. The removal efficiency of TC was 92.6% in the optimum oxidation conditions ([TC] = 15 mg/L, [PMS] = 50 mM, [CeO2] = 0.6 g/L, pH = 6, and US = 70 W) and followed the zero-order kinetics. Experiment scavenger demonstrated both sulfate and hydroxyl radicals (SO4•−, •OH) were responsible for degrading antibiotics. Biogenic CeO2 NPs and ultrasound waves-activated PMS is a promising technology for water pollution caused by contaminants such as pharmaceuticals.

Investigation of the boosted persulfate activation in the degradation of bisphenol A over MOF-derived cerium-doped Fe3O4 clusters with different shapes: the role of coordinatively unsaturated metal sites

“…In the past ten years, MOFs have exhibited potential advantages in diverse fields, such as gas adsorption and separation, biomedicine, and catalysis, and have received widespread attention. 7,8 Compared to traditional PMS-activating catalysts, MOFs exhibit fascinating structural characteristics, such as a very high specific surface area, abundant nanochannels, and high porosity, which accelerate the mass transfer of guest molecules such as PMS in the catalytic reaction. In addition, the well-dispersed metal sites in MOFs are the active sites for PMS activation in the oxidation reaction.…”