Toward combined photo-electrochemical system for degradation of ceftriaxone contaminated water over Ti-based mixed metal oxide photoanodes performance evaluation and mechanism insights

• Published in: Journal of the Taiwan Institute of Chemical Engineers 2024-12, Vol.165, p.105787, Article 105787
• Main Authors: Zarei, Mahmoud, Ranjbar, Ali, Hazrati Dorigh, Behnaz, Babaei, Tala, Rostamzadeh, Paria, Gheshlaghi, Alireza, Hosseini, Mir Ghasem
• Format: Article
• Language: English
• Subjects: Ceftriaxone; Photo-electrochemical oxidation; Photoanode; Ti/IrO2-Ta2O5-TiO2; Wastewater treatment
• ISSN: 1876-1070
• DOI: 10.1016/j.jtice.2024.105787

•Combined photo-electrochemical system was applied to investigate ceftriaxone removal.•Effect of operational parameters on photo-electrochemical system was optimized.•Effect of scavengers of removal efficiency of ceftriaxone was determined.•Applied photoanodes in optimal condition demonstrate 98.6 % of ceftriaxone degradation efficiency.•The photoanodes showed great performance in mineralization of ceftriaxone. As a growing environmental concern over the accumulation of antibiotics in aquatic environmets, the development of an efficient degradation process has been addressed. In this study, the application of the photo-electrochemical oxidation (PEO) process for the degradation of ceftriaxone was evaluated. Experiments were performed in an undivided cell equipped with Ti/IrO2 (0.1)-Ta2O5 (0.1)-TiO2 (0.8) and Ti/IrO2 (0.2)-Ta2O5 (0.2)-TiO2 (0.6) as anodes and Platinum (Pt) sheet as the cathode of the degradation process. Anodes were characterized using scanning electron microscopy (SEM), mapping energy dispersive X-ray (EDS-mapping), ultraviolet–visible diffuse reflectance spectroscopy (DRS), and atomic force microscopy (AFM). Cyclic voltammetry (CV) and photocurrent analysis were performed to consider the photo-electrochemical behavior of anodes. The effect of operational parameters, including initial pH (3–9), ceftriaxone initial concentration (C = 10–50 mg L−1), current density (I = 100–500 mA cm−2), and Na2SO4 as electrolyte concentration (Celectrolyte = 0.05–0.25 mg L−1) on ceftriaxone removal efficiency were determined. Outcomes of experiments revealed that under optimum conditions (pH = 6, C = 30 mg L−1, Celectrolyte = 0.1 mg L−1, and I = 300 mA cm−2), 98.6 % of degradation efficiency was achieved. The combined process resulted in 77.6 and 69.3 % total organic carbon removal of ceftriaxone on Ti/IrO2 (0.1)-Ta2O5 (0.1)-TiO2 (0.8) and Ti/IrO2 (0.2)-Ta2O5 (0.2)-TiO2 (0.6) after five hours of PEO process, respectively. Additionally, the feasible intermediates of ceftriaxone degradation were identified using Gas chromatography-mass spectroscopy (GC-MS) analysis. [Display omitted]