The continuous synthesis of Pd supported on Fe3O4 nanoparticles: a highly effective and magnetic catalyst for CO oxidation

Abstract

We report a facile approach used for the simultaneous reduction and synthesis of a well dispersed magnetically separable palladium nanoparticle supported on magnetite (Pd/Fe3O4 nanoparticles) via continuous flow synthesis under microwave irradiation conditions, using a Wave Craft’s microwave flow reactor commercially known as ArrheniusOne, which can act as a unique process for the synthesis of highly active catalysts for carbon monoxide (CO) oxidation catalysis. The prepared catalysts are magnetic, which is an advantage in the separation process of the catalyst from the reaction medium. The separation process is achieved by applying a strong external magnetic field which makes the separation process easy, reliable, and environmentally friendly. Hydrazine hydrate was used as the reducing agent under continuous flow reaction conditions. The investigated catalysis data revealed that palladium supported on iron oxide catalyst synthesized by continuous flow microwave irradiation conditions showed remarkable high catalytic activity towards CO oxidation compared to the ones that were prepared by batch reaction conditions under the same experimental conditions. This could be attributed to the high degree of dispersion and concentration ratio of the Pd nanoparticles dispersed on the surface of magnetite (Fe3O4) with a small particle size of 5–8 nm due to the effective microwave-assisted reduction method under continuous flow conditions. These nanoparticles were further characterized by a variety of spectroscopic techniques including X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), and transmission electron microscopy (TEM).

Keywords

• co catalytic oxidation
• continuous flow chemistry
• hydrazine hydrate
• magnetite (fe3o4)
• microwave heating
• pd-nanoparticles
• solid supported catalysis