Electro‐ F enton treatment of caffeine‐contaminated water using Ir – Ru electrodes: Process optimization, kinetic modeling, and comparative analysis

Electro‐Fenton (EF) processes are effective for the removal of emerging contaminants; however, their performance is governed by the electrochemical generation of hydroxyl radicals, which depends on the coupled interaction of operational parameters. In this study, caffeine degradation in aqueous solution was investigated using an EF system equipped with Ir–Ru oxide‐coated electrodes, with the aim of elucidating how current density, Fe 2+ concentration, and H 2 O 2 dosage interact to control process performance. Optimization of H 2 O 2 and Fe 2+ concentrations demonstrated that an equimolar 3 mM ratio enhanced the degradation pathway, achieving 99% removal within 180 min, compared to 79% removal obtained with electrooxidation alone. Process parameters were further optimized through response surface methodology (RSM), which identified the optimal conditions as a current intensity of 0.53 A, a reaction time of 50.19 min, and H 2 O 2 and Fe 2+ dosages of 2.98 and 2.93 mM, respectively. Under these settings, the model predicted a removal efficiency of 88.54%, which was closely validated by the experimental outcome of 88.23% with an estimated specific energy consumption of approximately 1.5 kWh/g. Pseudo‐first‐order kinetics were observed with a rate constant (k) of 0.019 min −1 , and the findings indicate that Ir–Ru‐based EF systems offer promising performance within the investigated experimental domain. This study provides a statistically supported framework for understanding parameter interactions in EF systems using alternative anode materials.