Preparation of tea residue supported nanoscale zero-valent iron and its removal of methanil yellow G from aqueous solution

In this paper, nanoscale zero-valent iron (nZVI) and tea residue supported nanoscale zero valent iron (TS60-nZVI) was prepared using the sodium borohydride reduction method, and used it to remove the methanil yellow G (MYG) from aqueous solution. It was found that TS60-nZVI was more efficient in removal of MYG with 92.55%. Furthermore, SEM showed that the tea residue as a supporter led to a decrease in aggregation of iron nanoparticles, the surface of TS60-nZVI was changed before and after used it to remove MYG, and XRD showed that the precipitation of iron oxide was observed. These indicate that Fe0 was oxidized during removal of MYG. In addition, kinetic study based on the experimental data indicated that the reaction fitted to pseudo first-order -model well and described with Langmuir-Hinshelwood kinetics equation, the apparent rate constants (Kobs) was 6.0 × 10-3 min-1 and half life was 115.52 min.