MnFe2O4 nanoparticles as new catalyst for oxidative degradation of phenol by peroxydisulfate

Manganese ferrite nanopowder was prepared by thermal decomposition at 400 degrees C of the gel synthesized from manganese and iron nitrates and polyvinyl alcohol. X-ray diffractometry evidenced that manganese ferrite was formed as single crystalline phase at this temperature. Scanning electron microscope images evidenced the formation of very fine spherical particles (d < 11 nm) of manganese ferrite, with specific surface area of 147 m(2)/g. The powder obtained at 400 degrees C was used as a catalyst for the oxidative degradation of phenol in aqueous solutions, in the presence of potassium peroxydisulfate as oxidant. High phenol removal efficiencies above 90% were reached at: pH 3-3.5, phenol initial concentration around 50 mg/L, peroxydisulfate: phenol mass ratio 10: 1, and catalyst dose 3 g/L. Total organic carbon measurements showed that the degradation of phenol goes, under these conditions, to mineralization in an extent of 60%. (C) 2016 The Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences. Published by Elsevier B.V.