| Article ID | Journal | Published Year | Pages | File Type |
|---|---|---|---|---|
| 45539 | Applied Catalysis B: Environmental | 2015 | 8 Pages |
•In-situ fabricate heterogeneous electro-Fenton catalyst from acid mine drainage.•Nano-scaled iron oxide/GF composites are obtained using an air-cathode fuel cell.•Fe3O4/GF exhibits higher electro-Fenton activity than Fe2O3/GF and FeOOH/GF.•Decomposition of H2O2 on iron oxides is completely surface-catalysis controlled.•Iron oxides maintain structures and show stabilities in recycling utilization.
Acid mine drainage (AMD) contains a large amount of ferrous iron and the recovery of iron oxides from the AMD has been of extensive research interest. Here we report a novel air-cathode fuel cell strategy to in-situ utilize ferrous iron in the AMD for the fabrication of heterogeneous electro-Fenton catalysts. Three types of nano-structured iron oxide/graphite felt (GF) composites, including FeOOH/GF, Fe2O3/GF and Fe3O4/GF, were fabricated from a synthetic AMD and their catalytic activities towards the electro-Fenton reaction were evaluated at neutral pH with Rhodamine B (RhB) as a probe pollutant. The electro-Fenton system with GF cathode only removed 30 ± 1.4% of RhB after 120 min of reaction. In comparison, RhB removal efficiencies were significantly improved to 62.5 ± 2.0%, 95.4 ± 0.9% and 95.6 ± 0.7% when the FeOOH/GF, Fe2O3/GF and Fe3O4/GF composites were used as the cathodes, respectively. Among the three types of composites, the Fe3O4/GF exhibited the highest electro-Fenton catalytic activity whereas the lowest activity was observed for the FeOOH/GF. The decomposition of H2O2 on the iron oxides followed a completely surface-catalyzed mechanism in which the iron oxides maintained their structures without leaching of iron species. The air-cathode fuel cell technology has a potential for iron recovery from the AMD, and provides an effective way for fabricating heterogeneous electro-Fenton catalyst with high catalytic activity and good stability.
Graphical abstractFigure optionsDownload full-size imageDownload as PowerPoint slide
