Activated carbon-supported nano zero-valent iron (nZVI@AC) for enhanced peracetic acid activation in Fenton-like degradation of sulfamethoxazole

This study presented a novel nano zero-valent iron anchored on activated carbon (nZVI@AC) catalyst, designed to overcome the inherent aggregation and oxidation limitations of bare nZVI. The nZVI@AC composite exhibited high catalytic activity for peracetic acid (PAA) activation, achieving complete degradation of sulfamethoxazole (SMX) within 10 min ( k obs = 0.3171 min -1 ). Characterizations confirmed that the AC support significantly enhanced electron transfer and increased the electron-donating capacity. This maximized exposure of active Fe 2+ species, which was crucial for efficient PAA activation and reactive oxygen species (ROS) generation. Radical quenching, electron paramagnetic resonance, and probe experiments identified hydroxyl radicals, singlet oxygen ( 1 O 2 ), and acetylperoxyl radicals as the primary ROS, with 1 O 2 playing the dominant role. The nZVI@AC/PAA system demonstrated remarkable stability and practical viability. This work established nZVI@AC as an efficient, stable, and versatile catalyst for PAA-based advanced oxidation processes, offering promising potential for water remediation applications.