Microwave-assisted co-precipitation preparation of CuFe2O4 photo-Fenton degradation tetracycline: Characterization, efficacy, stability in complex water quality and mechanism

A magnetic copper ferrite (CuFe2O4) photocatalyst was successfully synthesized by the modified microwave-assisted co-precipitation method to improve the removal performance of tetracycline (TC) and the reusability of a photocatalyst. A series of tests indicate that microwaves could reach the inside of the material quickly and uniformly with its energy so that CuFe2O4 exhibited a more significant specific surface area, magnetic intensity, and separation efficiency of photogenerated electron-hole pairs. CuFe2O4 reached superior photo-Fenton performance of TC in the presence of Cl-, NO3-, HCO3-, HPO42-, SO42- and humic acid, as well as deionized water, river water, and secondary effluent. Ten recycling tests in these three different water quality backgrounds confirmed the stability and remarkable activity of CuFe2O4, with the removal rate only decreasing by 2.0 %, 1.5 %, and 2.1 %, respectively. Free radical capture experiments as well as electron spin resonance suggest that center dot OH and O2(center dot-) were mainly involved in the degradation of TC, and the photo-Fenton degradation mechanism and equations were proposed. Toxicity evaluation declared that CuFe2O4 photo-Fenton degradation of TC was a safe and promising technology. This study offered prospects of magnetic CuFe2O4 prepared by the modified microwave-assisted co-precipitation method in TC wastewater treatment.