Magnetic Properties of Natural Hematite (Fe2O3) Extracted from Iron Ore by Co-Precipitation Method
Zulkarnain Jalil, Adi Rahwanto, Mustanir, Akhyar Hasan, Erfan Handoko

Universitas Syiah Kuala

Abstract

Nowadays, iron oxide plays a crucial role in various applications and intensively investigated, especially its application in magnetic materials. Unfortunately, economically is very low income since the exported of iron ore in the form of lumps of pure rock. In this paper, the mineral composition and magnetic behavior of nano Fe2O3 of iron ore from Lhoong mining area, Aceh province were studied. The iron ore was firstly prepared by mechanical milling method and then followed by co-precipitation method to obtain the pure hematite. 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 Fe2O3 (93.88%) in association with other isomorphous impurities, such as SiO2, MnO, and Al2O3 in varying proportions. Compare to XRD results, it was consistent with XRF, the phase compositions of iron ore were mainly hematite (Fe2O3). The XRD revealed that hematite was the major mineral components in the Lhoong iron ores. SEM observation was shown fine crystalline structure of Lhoong iron ore after milling process. The main mineral morphology was micro-crystalline in agglomerate forms. The magnetic properties of the samples after milling was showed the increasing in the remanent (Br) and coercivity (Hc). This increasing can be explained that nano-Fe2O3 phase after milling for 20 hours plays an important role in the magnetic behavior of Lhoong iron ore. It is understood that the longer milling time is sufficient to complete the transformation of hematite (Fe2O3) to magnetite (Fe3O4).

Keywords: Hematite, iron ore, nano-minerals, co-precipitation, ball milling

Topic: Material Science