Unveiling the efficacy and mechanism of chlortetracycline degradation by MnFeCu-LDH/GO activating of peroxymonosulfate†

Abstract

Antibiotics are frequently detected in aquatic environments, posing potential risks to ecological systems and human health. Among the various treatment strategies, advanced oxidation processes (AOPs) utilizing peroxymonosulfate (PMS) activation stand out due to their ease of activation and potent oxidative capabilities. This study synthesized manganese–iron–copper layered double hydroxides coupled with graphene oxide (MnFeCu-LDH/GO) using eco-friendly transition metals. Optimal conditions of pH 7, 298 K, and 0.2 g L⁻¹ dosage of both catalyst and PMS achieved 98% CTC removal in 30 minutes. The composite was employed for the degradation of chlortetracycline (CTC) through PMS activation. Reactive oxygen species (ROS), including ¹O₂, ˙OH, and SO₄˙⁻, were identified and quantified through trapping and quenching experiments, and ¹O₂ was identified, to be the most significant contributor to degradation. The catalyst demonstrated excellent reusability, maintaining high degradation efficiency after five cycles. These findings suggest that MnFeCu-LDH/GO-activated PMS is a promising method for mitigating antibiotic contamination in water.