Sulfur-doped mesoporous ferric oxide used for effectively activating H2O2 to degrade moxifloxacin

High energy consumption is the bottleneck in advanced oxidation processes (AOPs) for applying in eliminating refractory organic contaminants. Fenton catalysis is deemed to be the promising technology of AOPs to produce super-active hydroxyl radical ( ·OH) for tackling serious water environment pollution issues. Here, magnetic mesoporous sulfur-doped ferric oxide (PS-Fe) composite, prepared through simple co-precipitation method, was creatively introduced to activate hydrogen peroxide (H2O2) to generate ·OH for degrading emerging antibiotic moxifloxacin (MOX). The catalytic activity of PS-Fe was significantly elevated by sulfurization to achieve a degradation efficiency of 97 % and total organic carbon removal exceeding 44 % (within 30 min). Besides, we investigated the effects of catalyst dosage and H2O2 concentration, initial pH value, temperature, and humic acid concentration on MOX degradation. Quenching experiments results indicate that ·OH, O2 ·–, and 1O2 participated in the degradation process of MOX, and ·OH plays the predominant role. Additionally, possible activation mechanism is proposed and possible reaction intermediates are speculated. This work can offer a novel and reasonable interpretation for designing heterogeneous iron-based materials in activating H2O2 to degrade pollutants.