关键词: 赤泥, 非均相电芬顿技术, 零价铁, 资源利用, 废水净化

Abstract: The extensive use of antibiotics has led to their persistent accumulation in aquatic environments, triggering ecological risks such as antibiotic resistance gene dissemination. Heterogeneous electro-Fenton (HEF) technology shows great potential for water pollution treatment as it circumvents iron sludge generation and features simple operation. However, its practical application remains limited by sluggish Fe2+/Fe3+ cycling kinetics and high costs. This study developed a zero-valent iron-based catalyst (RMM-1:1) through co-pyrolysis of red mud (RM, an industrial waste) with waste molasses (another industrial byproduct). Characterization revealed that reductive gases from molasses pyrolysis effectively converted iron oxides in RM to Fe0, endowing RMM-1:1 with high specific surface area and rapid electron transfer capability. The optimized system achieved 93.6% removal of 30 mg·L-1 ciprofloxacin within 60 min (apparent rate constant: 0.1081 min-1) through enhanced Fe2+ regeneration and multi-path reactive oxygen species (·OH, 1O2, ·O2-) synergy. Mechanistic studies demonstrated that Fe0-mediated electron transfer coupled with non-radical pathways (1O2-dominated) synergistically drove pollutant removal. The sustained electron supply from Fe0 was identified as the core mechanism overcoming Fe2+/Fe3+ cycling bottlenecks, while spatiotemporal ROS synergy ensured degradation efficiency. This work establishes a cost-effective HEF catalytic system that integrates pollutant degradation with solid waste valorization, providing an innovative solution for practical antibiotic pollution control.

Key words: Red mud, Heterogeneous electro-Fenton technology, Zero-valent iron, Resource utilization, Wastewater purification