Highly efficient catalytic reduction of bromate in water over a quasi-monodisperse, superparamagnetic Pd/Fe3O4 catalyst

Abstract

A novel quasi-monodisperse, superparamagnetic Pd/Fe₃O₄ catalyst was synthesized for effective catalytic bromate reduction. The catalyst was prepared by dispersing nanoparticles of Pd (weight percent up to 1%) on the surface of superparamagnetic Fe₃O₄ microspheres with 300–500 nm in diameter and 10–20 nm in grain size. Complete reduction of bromate by this Pd/Fe₃O₄ catalyst was demonstrated within a short period (<2 h) over a range of pH values, in the presence of a variety of co-existing ions, and after multiple cycles. In addition, the superparamagnetic nature of the catalyst enhanced its good dispersion in water during water treatment when there was no external magnetic field, and its high saturation magnetization allowed an easy magnetic separation from water when an external magnetic field was applied after the water treatment. Thus, it could be easily recycled and reused, further enhancing its application potential.