摘要： Fe3O4 nanoparticles (NPs) have been widely used in photo-Fenton catalysis applications for water/waste water treatment. Their drawbacks, however, continue to limit their potential. In the present study, we synthesized magnesium aminoclay–iron oxide [MgAC–Fe3O4] nanocomposites in DI water solution by treated them under 4% H2/Ar for 3 hours in a 500 (cid:3)C furnace. Obtained X-ray diffraction (XRD) patterns con?rmed that the growth of the Fe3O4 NPs in the amorphous MgAC; also, scanning electron microscopy (SEM) images indicated that the MgAC–Fe3O4 nanocomposites were in an aggregated form of 170 ± 117 nm average-diameter. MgAC[0.7 g]–Fe3O4 nanocomposite exhibited the best photo-Fenton catalysis with methylene blue (MB) was completely removed from the treatment solution at a constant rate of 0.0083 (min?1(cid:2) on the batch scale. This performance was 13.83 times better than that of commercial Fe3O4. On the pilot scale (100 L), MgAC[0.7 g]–Fe3O4 nanocomposite took 12 hours to completely removed MB from tap water. The mechanism of the high photo-Fenton catalysis was attributed to the higher rate adsorption of MgAC as well as Brunauer-Emmett-Teller (BET) surface area.