Optimization and mechanistic insights into the electrochemically activated persulfate for highly efficient mineralization of nonylphenol

Nonylphenol (NP), a persistent endocrine-disrupting chemical, poses significant environmental and health risks due to its resistance to usual wastewater treatment methods. This study explores the electrochemical activation of persulfate (EPS) as an advanced process for the efficient mineralization of NP. Using a central composite design (CCD) and response surface methodology (RSM), the operating parameters—electrode potential, persulfate concentration, pH, NP concentration, and reaction time—were optimized to maximize NP removal efficiency. The results demonstrated that under optimal conditions (12 V electrode potential, 18.05 mM persulfate, pH 5.01, 10 mg/L NP, and 80 min reaction time), the EPS process achieved up to 87.95% NP removal. The synergistic effect of combining persulfate with electrochemical activation significantly enhanced the degradation efficiency compared to individual processes. The study also identified key intermediates and proposed a degradation pathway, confirming the breakdown of NP into less harmful compounds. The findings highlight the EPS process as a promising and efficient method for the treatment of NP-contaminated wastewater, offering a viable solution for mitigating the environmental impact of this hazardous pollutant. • Optimized EPS process achieved 87.95% NP removal under 12 V, 18.05 mM PS, pH 5.01, and 80 min. • Synergistic effect of EPS enhanced NP degradation compared to individual PS and electrochemical processes. • Key intermediates identified, proposing a degradation pathway for NP mineralization into less harmful compounds. • Toxicity unit reduced from 6.2 to <1, meeting US EPA discharge standards post-treatment. • EPS process offers a robust solution for efficient NP removal from contaminated wastewater systems.