Insights into sulfamethazine degradation by peroxymonosulfate activation using H2 reduced hematite in high-salinity wastewater: Performances and mechanisms

Sulfamethazine (SMT) is recognized as a persistent, bioaccumulate, and toxic antibiotic pollutant that is difficult to be completely eliminated through traditional wastewater treatment methods. Although advanced oxidation processes (AOPs) utilizing peroxymonosulfate (PMS) have demonstrated potential in degrading SMT, the lack of inexpensive and efficient PMS activators remains a significant obstacle for its practical application. In this study, we present the synthesis of a highly effective PMS activator, the naturally-occurring minerals-based material − H₂– reduced hematite (HRH), on an industrial scale using a fluidized bed reactor. Impressively, within the PMS AOPs system, the synthesized HRH catalyst not only achieves 99.3 % degradation of SMT within 20 min, demonstrating a remarkable 10-fold increase in the degradation rate compared to pristine hematite, but also showcases excellent recyclability and durability. Additionally, this HRH/PMS system were proved to effectively remove SMT under high-salinity conditions. More importantly, through systematic characterization and theoretical calculations, an in-depth investigation into the primary activation mechanism and degradation pathway in this reaction process is provided. This work provided a highly feasible strategy for the application of natural mineral-based catalyst for the degradation of pollutants via PMS activation in high-salinity wastewater.