Red mud supported on reduced graphene oxide as photo-Fenton catalysts for organic contaminant degradation

In this study, the reduced graphene oxide (rGO) modified red mud (RM) composite was successfully prepared and used as the highly effective heterogeneous photo-Fenton catalyst for Rhodamine B (RhB) contaminant degradation. The acid leaching and calcination treatment reduced the impurities in RM, making alpha-Fe2O3 active for H2O2 decomposing. The rGO modification can not only inhibit the recombination of charge carriers but also accelerate the Fe3+/Fe2+ cycle during heterogenous Fenton process. Attributed to such advantages, 99.8% degradation of RhB within 20 min was achieved by the optimal RM-H/rGO composite. More importantly, the prepared RM-H/rGO showed excellent performance and high stability for various organic contaminants degradation at a wide pH range. This study not only demonstrates that rGO-modified RM can be used as an efficient, low-cost photo-Fenton catalyst for organic pollutants treatment, but also provides an effective approach for RM disposal.