Synthesis of nano- hematite (Fe_2O_3) extracted from natural iron ore prepared by mechanical alloying method

摘要

In this paper, the mineral composition and magnetic behavior of nano iron oxide of iron ore from Lhoong mining area, Aceh province were studied. The iron ore was prepared by mechanical alloying method. Through Electron Microscope identification, it shown there are fine crystalline structure of Lhoong iron ore. The main mineral morphology is micro-crystalline or agglomerate forms. The mineral and chemical compositions of samples were investigated by XRD and XRF analysis tests. The XRF test showed that the Lhoong iron ore contain Fe_2O_3 (93.88%) in association with other isomorphous impurities, such as SiO_2, MnO, and Al_2O_3 in varying proportions. Compare to XRD results, it was consistent with XRF, the phase compositions of iron ore are mainly hematite (Fe_2O_3). The XRD revealed that hematite is the major mineral components in the Lhoong iron ores. The magnetic properties of the samples after milling showed there has been increased in the remanent (Br) and coercivity (Hc). This increasing can be explained that nano-Fe_2O_3 phase after the milling process plays an important role in the magnetic behavior of Lhoong iron ore.