Modifying organic carbon in Fe3O4-loaded schwertmannite to improve heterogeneous Fenton activity through accelerating Fe(II) generation

The conversion of-Fe(III) to-Fe(II) in the heterogeneous Fenton is low efficient to enhance catalytic activity. Biogenic schwertmannite (Sch), as an iron-based catalyst, is usually formed via Fe(II) oxidation mediated by Acidithiobacillus ferrooxidans (A. ferrooxidans), and contains low organic carbon mainly originated from exopolymeric substances. Owing to the magnetic inter-attraction between A. ferrooxidans and Fe3O4, the introduction of strong magnetic Fe3O4 during synthesis process of biogenic Sch can modify more organic carbon in Sch-based catalyst. Surprisingly, Fe3O4-loaded Sch with organic carbon (Fe3O4/Sch/C) exhibits much higher activity for fluoroquinolone antibiotics degradation than Sch, Fe3O4, and Fe3O4-loaded Sch without organic carbon, which is mainly ascribed to more electrons provided by organic carbons for promoting-Fe(II) generation in heterogeneous Fenton. This finding not only provides an ecofriendly, cost-effective, and efficient catalyst, but also gives a new sights into the potential application of iron oxyhydroxysulfate with green carbon-source for contaminants removal.

Automated summary

The conversion of Fe(III) to Fe(II) in heterogeneous Fenton is inefficient, but introducing magnetic Fe3O4 during the synthesis of biogenic schwertmannite (Sch) can enhance the catalytic activity. Fe3O4-loaded Sch with organic carbon (Fe3O4/Sch/C) shows much higher degradation activity for fluoroquinolone antibiotics compared to other catalysts, mainly due to the more electrons provided by organic carbons promoting Fe(II) generation in heterogeneous Fenton.