Comparative electrochemical removal of Tamoxifen from aqueous solutions

Gebze Technical University, Department of Environmental Engineering, 41400 Gebze, Kocaeli, Turkiye

Abstract

The increasing presence of pharmaceutical micropollutants in aquatic environments demands the advancement of effective treatment technologies. In this study, electro-oxidation (EO), electrocoagulation (EC), and electro-Fenton (EF) processes were comparatively evaluated for the removal and mineralization of tamoxifen citrate (TAM) from aqueous solutions. The effects of key operational parameters, including pH (3–11), conductivity (1.5–10 mS/cm), current density (50–500 A/m²), and initial concentration (2.5–10 ppm), were systematically investigated. Under optimized conditions, EO achieved the highest total organic carbon (TOC) removal efficiency (84.4%) at 300 A/m², pH 4.5, and conductivity 3.5 mS/cm. The EF process demonstrated comparable performance, achieving an 83.7% TOC removal rate with 0.1 mM Fe²⁺ at pH 5, confirming the effectiveness of hydroxyl radical-based oxidation. In contrast, EC resulted in a lower removal efficiency (60.3%), primarily due to its coagulation-dominant removal mechanism. Spectrophotometric analyses revealed significant mineralization in both EO and EF systems, demonstrating the formation and subsequent degradation of intermediate compounds. Overall, EO and EF showed superior performance compared to EC in TAM treatment, highlighting their potential for removing persistent pharmaceutical contaminants. These findings provide practical insights for selecting appropriate electrochemical treatment strategies in wastewater applications.