Electrocatalytic Deep Dehalogenation of Florfenicol in Wastewater: Performance, Mechanism, and Toxicity Assessment

Abstract

The widespread discharge of halogenated antibiotics into aquatic environments poses serious threats to ecosystem safety and human health because of their high toxicity, persistent antibacterial activity, and resistance to biodegradation. Electrocatalytic hydrodehalogenation (EHDH) driven by adsorbed atomic hydrogen (H*ads) has been recognized as a highly effective strategy to cleave carbon–halogen bonds to reduce the toxicity. In this work, a Co–Ni dual-metal catalysis anchored on N-doped carbon (CoNi/N–C) achieved 100% degradation of florfenicol (FLO), which is a representative halogenated antibiotic. The degradation pathway was investigated by LC–MS identification of its intermediates and products and the detection of released ions. Moreover, it exhibited superior catalytic stability and remarkable robustness in complex water matrixes, highlighting its applicability for industrial wastewater treatment. Importantly, the EHDH process resulted in the nearly complete elimination of toxicity for halogenated antibiotics. This study provides a cost-effective and sustainable electrocatalytic strategy for the detoxification of halogenated antibiotics in wastewater.