• • Optimal EDTMPS degradation of 99.48% was achieved at 50 °C, 300 mL·min−1, 7.0 V, pH 10, and 0.05 mol·L−1 Na2SO4, demonstrating near-complete removal under moderate conditions.
• • The presence of chloride ions enhanced degradation rates compared to chloride-free systems, though the improvement was marginal; EPR confirmed the generation of chlorine radicals in addition to hydroxyl and sulfate radicals.
• • In a coexisting system with benzotriazole (BTA), degradation efficiencies for EDTMPS and BTA were comparable under conditions of 0.05 mol·L−1 Na2SO4, 40 °C, 390 mL·min−1, 7.0 V, and pH 8, indicating non-selective oxidation.
• • The degradation mechanism involves both direct anodic oxidation and indirect oxidation via reactive radicals, with indirect oxidation playing a dominant role, leading to complete mineralization into CO2, PO4^3−, and N2.