Characterization of Iron–Polyphenol Nanoparticles Synthesized by Three Plant Extracts and Their Fenton Oxidation of Azo Dye

Abstract

In this paper, iron–polyphenol nanoparticles (Fe–P NPs) were synthesized using the extracts obtained from Australian native plant leaves, these being Eucalyptus tereticornis, Melaleuca nesophila, and Rosemarinus officinalis . The Fe–P NPs synthesized from the extracts were characterized using scanning electron microscopy (SEM), energy dispersive spectrometer (EDS), X-ray diffraction (XRD), and Fourier transform infrared spectroscopy (FTIR). The results show that the reaction between iron ions and polyphenols can form complex nanoparticles with sizes ranging from 50 to 80 nm, the surface of which presents organic characters. The synthesized nanoparticles were then utilized as a Fenton-like catalyst for decolorization of acid black 194 in solution. The batch experiments showed that 100% of acid black was decolorized, and over 87% total organic carbon (TOC) was removed. In addition, removal of acid black 194 fitted well to the pseudo-first-order model. Compared with the conventional Fenton reaction, the Fenton-like reaction with Fe–P NPs takes place more sustained and carefully within 200 min. Furthermore, it does not need to adjust pH for the reaction.