Sepiolite-metal organic framework-iron oxide catalyst for degradation of Rhodamine B using Fenton-like process

The catalytic degradation of harmful organic pollutants, i.e., Rhodamine B (RhB), is very valuable from the environmental viewpoint. In this way, the design and fabrication of an effective heterogeneous catalyst has a prospect in the treatment of dye containing effluents. The magnetic catalyst was prepared by first successfully deposition of the MOF(801) material on clay substrate using a solvothermal process to form Sep-MOF(801) and subsequent formation of ultrafine Fe3O4 nanoparticles via a simple chemical precipitation route on the surface of Sep-MOF(801) to prepare Sep-MOF(801)-Fe3O4. The morphological and structural characters of the Sep-MOF(801)-Fe3O4 nanocomposite were explored using FT-IR, BET, XRD, TEM, SEM, EDX, VSM and XPS methods. Experimentally, the RhB degradation efficiencies at various Fenton-like systems abided by the order of Sep-MOF(801)-Fe3O4/H2O2+NH2OH > Fe3O4/H2O2+NH2OH > Sep-MOF(801)/H2O2+NH2OH > Sep/H2O2+NH2OH > MOF(801)/H2O2+NH2OH > H2O2+NH2OH. The presence of NH2OH as reducing agent can further improve the RhB degradation performance and led to less consumption of H2O2. Under the optimum experimental conditions, 50 mg L−1 RhB was completely degraded in 12 min. In addition, the reusability of the Sep-MOF(801)-Fe3O4 catalyst was investigated after six repeated catalytic cycles.