Iron ore classification by XRD-Rietveld and cluster analysis

Abstract

This study establishes a routine for quantitative phase analysis by X-ray diffraction (XRD-Rietveld) in iron ore samples. Studied samples came from Quadrilátero Ferrífero, Southeastern Brazil, and are mainly composed by hematite, magnetite, goethite, quartz and kaolinite, being divided in three clusters: cluster 1 (n = 8), characterized by the presence of hydrated phases goethite (25 to 72 wt %), kaolinite (< 25 wt %) and gibbsite (< 10 wt %), plus hematite (7 to 54 wt %) and quartz (2 to 19 wt %); cluster 2 (n = 16), which consists of hematite (22 to 81 wt %) and quartz (2 to 58 wt %) and smaller proportions of goethite (< 22 wt %) and kaolinite (< 13 wt %); and cluster 3 (n = 3), that has a predominance of quartz (62 to 74 wt %) and smaller amounts of hematite (17 to 33 wt %) and kaolinite (< 5 wt %). Classification of ores by XRD-Rietveld and cluster analysis is a fast, low-cost and reliable option for substituting ore classification with chemical analysis.

Keywords

• Iron ore
• X-ray diffraction
• Rietveld method
• Cluster analysis.