Photocatalytic degradation of oxytetracycline in water by Pr6O11/ZrO2

In this study, ZrO2-based composite photocatalytic coatings modified with Pr6O11 up-conversion materials were proposed for the removal of oxytetracycline(OTC) from wastewater. The Pr6O11/ZrO2 composite photocatalyst powder was prepared by means of an ultrasound-assisted co-precipitation method, and the Pr6O11/ZrO2 photocatalytic coatings were prepared using polyurethane as the matrix resin with high-speed stirring and ultrasound-assisted by an electric mixer. The characterization of the Pr6O11/ZrO2 photocatalysts was conducted using a range of analytical methods,including X-ray diffraction, scanning electron microscopy,energy dispersive spectroscopy, and UV-visible diffuse reflectance spectroscopy. The study revealed that the incorporation of Pr6O11 the specific surface area of the Pr6O11/ZrO2 composite. The modified Pr6O11/ZrO2 composite photocatalysts exhibited bandgap energies as low as 2.19 eV, along with a broad spectral utilization range extending up to 625 nm. The impact of Pr6O11 doping ratio, dosing amount of Pr6O11/ZrO2, and initial concentration of OTC on the degradation of concrete-loaded photocatalytic coatings on OTC was investigated separately. Furthermore, the experimental conditions for the removal of OTC were optimized using response surface methodology, and it was concluded that the maximum removal of OTC could reach 85.97% when the doping ratio of Pr6O11 was 0.45, dosing amout of Pr6O11/ZrO2 was 1.4 g/L, and the concentration of OTC was 30.45 mg/L. The findings of this study suggest that Pr6O11/ZrO2 exhibits remarkable photocatalytic activity and holds considerable promise for the treatment of wastewater containing OTC.