Enhanced Persulfate Activation and Micropollutants Decontamination by In Situ Generated MnO2 in Carbon Nanotubes/Permanganate System

A growing challenge worldwide is the mitigation and elimination of micropollutants in natural bodies of water. Standard approaches for micropollutants removal typically have been energy-intensive and have required extensive use of chemicals and process operations. Here, an effective system for treating water is proposed that utilizes the synergistic action of peroxydisulfate (PDS) and permanganate (PM) with carbon nanotubes (CNT). Together, the materials were effective in the degradation of micropollutants, such as phenol, tetracycline (TC), 4-chlorophenol (4-CP), and bisphenol A (BPA). The combined CNT/PM/PDS system achieved a 2.97 mmol/(h·m2) BPA oxidation flux and had a high kinetic constant of 1.456 min–1, which compared favorably with the fluxes of 0.89, 0.27, 0.82, 1.27, and 0.81 mmol/(h·m2) and kinetic constants of 0.115, 0.076, 0.220, 0.779, and 0.661 min–1 for PM, PDS, PM/PDS, CNT/PM, and CNT/PDS, respectively. Investigations of the reaction mechanism determined that CNT could appreciably enhance the activation of PDS with Mn(III) and MnO2 generated in situ, thereby significantly enhancing the efficient consumption of both PM and PDS. The outcomes of this study are dedicated to providing an efficient, economical approach for water decontamination.