Efficient performance of porous Fe2O3 in heterogeneous activation of peroxymonosulfate for decolorization of Rhodamine B

Porous Fe2O3 particle was synthesized by the hydrothermal-calcination method and then used to activate peroxymonosulfate (PMS) for Rhodamine B (RhB) decolorization. Several analytical means such as X-ray powder diffraction (XRD), scanning electron microscopy (SEM), and N-2 physisorption were used to determine the characteristics of the catalyst particles. The results of experiments indicated that the catalyst showed a high activity in decolorization of RhB in the presence of PMS. Several key parameters including initial pH, amounts of catalyst, PMS concentration, and temperature were investigated in order to understand their effect on the decolorization efficiency. Furthermore, the catalyst showed good reusability and stability after three recycles. Finally, the free radicals participating in the process were classified by radical quenching studies, and a rational mechanism was proposed based on the results obtained to understand the catalytic process. (C) 2013 Elsevier B.V. All rights reserved.