Synthesis and properties of pyrrhotite ash based cubical α-Fe2O3 nanoparticles

Abstract

Pyrrhotite ash is a solid waste widely generated from the phosphate industry and has been used in this present research as a source material for α-Fe2O3 nanoparticles synthesis. The iron extraction conditions from pyrrhotite ash using hydrochloric acid were carried out under the optimized conditions. The obtained FeCl3 was deployed in the elaboration of hematite (α-Fe2O3) nanoparticles using the co-precipitation method where green tea extract was deployed as a reducer and capping agent. The prepared α-Fe2O3 nanoparticles were characterized by XRD, SEM, FTIR and BET techniques. The prepared sample consists of cubical or spherical microporous nanoparticles with sizes ranging from 56 to 116 nm and average pore size of 0.78 nm. The elaborated nanoparticles are of high purity having a crystalline size ranged from 18.33 to 24.55 nm. The optical properties were investigated using UV–visible spectroscopy, the maximum visible light absorbance was observed at 350 nm while the corresponding gap band was determined as 2.11 eV. Furthermore, the Vibrating-sample magnetometer was used to examine the magnetic properties of the nanoparticles that appropriate a ferromagnetic behaviour with high Ms, Mr, and Hc values of 14.59 emu/g and 4.72 emu/g −769.35 Oe.