Targeted degradation of Bisphenol A with peroxymonosulfate activated by nanoscale zero-valent iron supported on molecularly imprinted polymers

Abstract

In order to address the limitation of active species being influenced by the complex water environment during the degradation of target pollutants, a catalyst called MIP-nFe0 was prepared. This catalyst consists of nanoscale zero-valent iron (nFe0) supported on molecularly imprinted polymers (MIPs) with specific recognition. It was designed for the targeted degradation of Bisphenol A (BPA) by activating peroxymonosulfate (PMS). Material characterization confirmed that nFe0 was successfully loaded onto MIPs without agglomeration and did not cause significant damage to the MIPs structure. Under specific conditions (50 mg/L BPA and 100 mg/L catalyst), PMS activation with MIP-nFe0 rapidly degraded most BPA in just 0.5 min. Competitive adsorption and degradation experiments revealed that MIP-nFe0 displayed the best adsorption (21.02 mg/g) and degradation (28.89 mg/g) efficiency for BPA compared with the control materials nFe0 and nFe0 supported on non-imprinted polymer (NIP-nFe0). MIP-nFe0 was further applied in the actual water background for BPA removal, MIP-nFe0 maintained efficient BPA removal in both river water as well as sewage plant tail water, which was significantly higher than NIP-nFe0 and nFe0. Free radical capture and quenching experiments demonstrated that active species of SO4−·, ·OH, ·O2−, and 1O2 existed in the system, with SO4−· played a major role.