Fe-Cu co-doped carbon-based catalyst activating peroxydisulfate for the degradation of tetrabromobisphenol A: The dominant role of superoxide radicals

Abstract

Tetrabromobisphenol A (TBBPA) is highly biotoxic and difficult to remove, and there is an urgent need to provide an efficient method for addressing this environmental challenge. In this work, Fe3Cu2@NPC was prepared by calcination to activate peroxydisulfate (PDS) for the degradation of TBBPA. The results showed that TBBPA was completely removed within 20 min (kobs = 0.2476 min−1) and up to 90 % removal of total organic carbon (TOC) in the Fe3Cu2@NPC/PDS/TBBPA system. The cycling between Fe and Cu greatly promoted the degradation effect and had high degradation activity under neutral to alkaline conditions (pH = 7–11). Quenching experiments, EPR experiments, and steady-state concentration calculations show that TBBPA is degradated mainly by the free radical pathway, and the main active substance is O2−. The possible degradation paths of TBBPA mainly included debromination, dehydroxylation, and β-bond breakage. Fe3Cu2@NPC can be magnetically recycled and maintain high activity after reuse over four cycles.