Efficient degradation of tetracycline <i>via</i> iron(II,III) oxide nanoparticle-activated hydrogen peroxide: mechanisms and performance

Abstract Magnetite-enriched mining tailings are a cost-effective and abundant catalytic material with inherent magnetic recyclability. Yet their practical application in catalysis is often constrained by their limited surface area and sluggish reaction kinetics. To address these issues, we developed a facile one-step co-precipitation method to synthesize a magnetic nano-Fe 3 O 4 (MNP) catalyst that exhibits enhanced surface reactivity for efficient activation of H 2 O 2 towards tetracycline (TC) degradation. The system achieved complete (100%) removal of TC at an initial concentration of 20 mg L –1 within 90 min and demonstrated robust catalytic performance across weakly acidic to neutral pH conditions. Mechanistic investigations confirmed that ⋅OH is the primary reactive oxygen species involved, with ⋅O 2 ⁻ and 1 O 2 providing supplementary contributions to the degradation. Remarkably, the intrinsic magnetic properties ensured efficient MNP catalyst recovery. This work provides a sustainable and scalable wastewater treatment strategy, leveraging mining tailings as a cost-effective resource to treat wastewater while also providing economic and environmental benefits.