Rapid Decolorization of Acid Orange II by Hydrogen Peroxide with Fe-Ni-Al-MMT

Montmorillonite pillared with Fe-Ni-Al was synthesized by ion exchange method and used as heterogeneous catalysts for catalytic wet peroxide oxidation (CWPO) degradation of azo dye Acid Orange II (OII). The catalyst was characterized by BET, XRD and FT-IR. The effects of the initial pH, the concentration of H₂O₂ and the reaction temperature on the rate of decolorization were investigated in detail. In addition, the reaction kinetics for the decolorization process was also investigated. The catalytic reaction results showed that at a reaction temperature of 333 K, pH=3.0 and 24 mM H₂O₂, 97.9% decolorization of OII was achieved after 60 min treatment. Furthermore, kinetic analyses based on the experimental data elucidated that the decolorization process followed a first order exponential decay kinetics model. The activation energy was determined to be 25.2 kJ/mol.