This study investigated the mechanism and kinetic modeling of electrolytic degradation of ammonia with Pt/Ti anode. The results show that ammonia oxidation from direct oxidation or indirect oxidation with hydroxyl radicals was slow but can be observed under pH 9 and high initial ammonia concentration of 1,050 mg N L−1. Indirect oxidation with HOCl was the mechanism for the chloride-mediated electrolytic removal of ammonia. In this process, pH between 3 and 9 had little effect on the ammonia removal rate, but current density (j) and chloride concentration ([Cl]) showed a linear relationship with ammonia removal rate within the range of 3.8–15.4 mA cm−2 and 30–300 mg L−1, respectively. The ammonia removal could be described by a pseudo-zero order kinetics with a mathematic equation of k = 0.0003 × [Cl] × j − 0.076. Treatment of the actual wastewater effluent from a secondary clarifier in a local wastewater treatment plant showed an ammonia removal rate of 0.8 mg N L−1 h−1 and energy cost of 14 kJ per mg N ammonia.

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