Abstract
Advanced oxidation processes (AOPs) have gained traction as alternative solutions for eliminating pollutants from pharmaceutical wastewater for reuse. In this research, the performance of two photo-catalysts (Commercial TiO2 and synthesis N-doped TiO2) were compared in terms of the degradation of amoxicillin and ciprofloxacin from an aqueous solution using a photo-catalytic batch system under solar irradiation. The influence of five operating factors is: pH (5–11), H2O2 concentrations (200–600) mg/L, catalyst concentrations (25–100 mg/L), Antibiotic concentration (25–100) mg/L and reaction time (30–120 min), on the oxidation of the listed above pollutants were investigated using the central composite design (CCD) of response surface methodology (RSM). The catalyst of N-doping TiO2 was synthesized by sol-gel method, using the urea (CH4N2O) as a nitrogen source. The resulting material was analyzed using Scanning Electron Microscopy (SEM), X-Ray diffraction (XRD) and Fourier transform infrared spectroscopy (FTIR). Additionally, it can be observed from the analysis of the characteristics of N-doped TiO2 the homogenous dispersion of nitrogen molecules, small particle sizes, and energy-gap reduction, prompting a 6% increase in antibiotic degradation compared with Com. TiO2. In the RSM analysis, the ideal conditions were found to be a pH of 5, H2O2 conc. of 400 mg/L, catalyst conc. of 50 mg, and antibiotics conc. of 25 mg/L for an antibiotics reduction rate of 89.31% (AMOX/Com. TiO2/Solar), 90.2 (CFX/Com. TiO2/Solar), 95.8% (AMOX/N-TiO2/Solar) and 97.3% (CFX/N-TiO2/Solar). Experimental results were in good agreement with predictions because the predicted R2 matched well with the adjusted R2.
Acknowledgments
The authors are very grateful to the University of Mosul/Environmental Engineering laboratory for funding this work and providing the facilities which helped to improve the quality of this work.
Data availability
The data that support the findings of this study are openly available in [Zenodo] at http://https://doi.org/10.5281/zenodo.5755824, reference number [5755825].
Funding
The author(s) reported there is no funding associated with the work featured in this article.