Degradation of Antibiotic Chlortetracycline in Aqueous Solution by Ce/Bi2WO6 Photocatalysis under Solar Light

Pollution of surface and groundwater resources with antibiotics creates problems for human health, meanwhile, because of development of antibiotic resistance in bacteria. Chlortetracycline (CTC) is a tetracycline antibiotic, for which different removal methods were developed. Therefore, this study evaluated the removal efficiency of CTC from aqueous solutions using a photocatalytic process. In this study, Bi2WO6 was synthesized by microwave method and Ce loaded on Bi2WO6 by wet impregnation method. The prepared photocatalysts were characterized by XRD, FTIR, SEM, BET/BJH, DRS analysis. The degradation of CTC was investigated by the photocatalysis under solar light. Among the photocatalysts, Ce/Bi2WO6 (8%) had the highest CTC degradation efficiency. Response surface methodology (RSM) with central composite design (CCD) was used to investigate pH, time (min), mass of catalyst Ce/Bi2WO6 (8%) (g), and concentration of CTC (mg/L). In optimal conditions at pH 3.19, time 201.07 min, mass of Ce/Bi2WO6 (8%) of 0.05 g, and concentration of CTC 24.99 mg/L the photocatalytic degradation percentages of CTC were found to be 99.99%. Isothermic studies have shown that Fritz-Schlunder isotherms provide the best fit with the least error with experimental data.

Automated summary

This study evaluated the removal efficiency of chlortetracycline from aqueous solutions using a photocatalytic process, finding that Ce/Bi2WO6 (8%) exhibited the highest degradation efficiency. Response surface methodology was employed to investigate factors influencing the photocatalytic degradation of chlortetracycline, leading to the determination of optimal conditions.