Photocatalytic activity of electric-arc furnace flue dusts

Abstract

Two electric-arc furnace flue dusts, a waste generated during the steel production process,were characterized and their photocatalytic activity was assessed. Chemical compositionby X-ray fluorescence (XRF) analysis identified that both dusts were principally formed byiron, zinc and chromium oxides. Structural characterization carried out by X-ray diffrac-tion patterns (XRD), and micro-Raman measurements demonstrated that ZnFe2O4(zincferrite), FeCr2O4(chromite) and ZnO (zincite) are present in both waste dusts as majorityphases. Scanning electron microscopy (SEM) images showed that both dusts are formedby nanoparticles with a globular and octahedral morphology characteristic of the type offlue dusts formation and the obtained phases. Cathodoluminescence (CL) spectra show thecharacteristics bands of spinel structure (ZnFe2O4) and Fe3+emission. X-ray photoelectronspectroscopy (XPS) measurements indicate that Fe ions could be present in 2+ and 3+ oxida-tion state in the spinel structure, while zinc and chromium ions are in 2+ and 3+, respectively.In addition, the photocatalytic experiments demonstrated that the analyzed samples couldbe useful as photocatalyzed showing a degradation percentage above 75 %.