Activation of peroxymonosulfate with magnetic and recyclable Fe3 O4 @C/MnCo2 O4 nanocomposites for the decolorization of Acid Orange II

Abstract

BACKGROUND Synthetic dyes present in wastewater from many industrial sections and they cause serious problems to human and aquatic life. The development of novel and effective peroxymonosulfate (PMS) activator is highly demanded in order to eliminate dyes pollution. In this regard, new magnetic nanocomposite Fe3O4@C/MnCo2O4 was prepared and characterized. The activity of Fe3O4@C/MnCo2O4 as heterogeneous catalyst for PMS activation was evaluated by the decolorization of Acid Orange II (AO II). RESULTS With “Fe3O4@C/MnCo2O4 + PMS” system, the dye solution could be nearly completely decolorized in about 25 min within a wide pH range (pH 4.1−8.1), and 98% removal could be achieved in 15 min without pH adjustment (pH = 6.38). The influences of solution pH, dosages of catalyst and PMS, reaction temperature, and PMS activation mechanism were studied. It was found that sulfate radicals were the primary species responsible for the oxidation of AO II. The catalyst was magnetically separable and displayed good stability and reusability for six cycles use without deterioration in its performance. CONCLUSION This study demonstrated the easy recycling and high activity of Fe3O4@C/MnCo2O4 composite in PMS activation for the decolorization of AO II solution. It supplies a promising way for the decontamination of organic pollutants.