Self-destruction of a tire-derived quinone pollutant by peroxyacetic acid

N -(1,3-Dimethylbutyl)- N '-phenyl- p -phenylenediamine (6PPD) and its ozonation product, 6PPD-quinone (6PPD-Q), are contaminants of global concern due to their widespread occurrence and acute toxicity to aquatic organisms. Conventional treatment methods often fail to its complete removal in water. Peroxyacetic acid is extensively employed in advanced oxidation processes; however, it relies generally on ultraviolet light irradiation to generate reactive radical species. Here, we demonstrate for the first time that the target pollutant 6PPD-Q reacted with peroxyacetic acid to promote radical amplification and induced its own degradation without external energy input. Batch experiments were conducted under with and without ultraviolet irradiation at nearly neutral pH with varying peroxyacetic acid concentrations. The reaction of 6PPD-Q with peroxyacetic acid promoted radical amplification via electron transfer and semiquinone radicals formation, enabling 6PPD-Q degradation with more than 70% removal at 65 µM peroxyacetic acid, and complete degradation within 60 min at 263 µM peroxyacetic acid. Ultraviolet irradiation, while not required for semiquinone radical formation, enhanced overall degradation by promoting additional radical generation. Overbally, we provide the first evidence of pollutant-driven peroxyacetic acid activation and radical amplification, offering new insight into quinone-mediated oxidant activation and a catalyst-free remediation strategy for quinone-derived contaminants.