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Electrochemical degradation of an emerging contaminant, triclosan (5‐chloro‐2‐(2,4‐dichlorophenoxy) phenol) by a Ti/SnO2‐Sb/Ce‐PbO2 anode was investigated. The degradation efficiency attained >99.9% during 5 min of electrolysis at all influential factors, i.e., applied current density (2–10 mA/cm2), pH 3–11, inter‐electrode distance (1–4 cm), initial concentration (0.5–5 mg/L triclosan) and supporting electrolyte (10 mmol/L NaCl). Total organic carbon removal ratio achieved 79.7% at the optimal conditions after 2 min of electrolysis. The electrochemical degradation of triclosan followed pseudo‐first‐order kinetics. The intermediate products namely 2,4‐dichlorophenol, 5‐chloro‐3‐(chlorohydroquinone) phenol and 2‐chloro‐5‐(2,4‐dichlorophenoxy) benzene‐1,4‐diol were prominently detected using liquid chromatography–tandem mass spectrometry. A degradation mechanism of triclosan at the Ti/SnO2‐Sb/Ce‐PbO2 anode was proposed based on the intermediates. The energy consumption of triclosan (4 mg/L) degradation at different electrode distances (1–4 cm) was 0.466–2.225 kWh m−3. The Ti/SnO2‐Sb/Ce‐PbO2 anodes can be employed preliminary for rapid degradation of triclosan in wastewater.

Electrochemical degradation of rhodamine B (C28H31ClN2O3) over Ti/SnO2-Sb anode was investigated in a rectangular cell. The degradation reaction follows pseudo-first-order kinetics. The degradation efficiency of rhodamine B attained >90.0% after 20 minutes of electrolysis at initial concentrations of 5 to 200 mg/L at a constant current density of 20 mA/cm2 with a 10 mmol/L Na2SO4 supporting electrolyte solution. Rhodamine B (50 mg/L) degradation and total organic carbon (TOC) removal ratio achieved 99.9 and 86.7%, respectively, at the optimal conditions after 30 minutes of electrolysis. The results showed that the energy efficiency of rhodamine B (50 mg/L) degradation at the optimal current densities from 2 to 30 mA/cm2 were 23.2 to 84.6 Wh/L, whereas the electrolysis time for 90% degradation of rhodamine B with Ti/SnO2-Sb anode was 36.6 and 7.3 minutes, respectively. The electrochemical method can be an advisable option for the treatment of dyes such as rhodamine B in wastewater.

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