Crystalline Phase Quantitation of Sintered Ore with Powder X-ray Diffractometry with Rietveld Refinement

摘要

X-ray diffractometry (XRD) with Rietveld refinement was applied to the crystalline phase analysis of two certified standard sintered ores (JSS 851-2 and JSS 851-5) and an industrial sintered ore (SO-1). An eskolaite (Cr_(2)O_(3)) powder was mixed at 10 mass% with each sintered ore sample as an internal standard to correct for the effect of amorphous phase and unknown crystalline phases. The results of Rietveld refinement for JSS 851-2 were 23.0 mass% hematite, 29.5 mass% magnetite, 39.8 mass% silico ferrites of calcium and aluminum, 5.6 mass% dicalcium silicate, and 2 mass% amorphous phase, and these values are within the range previously reported for its phase composition. The elemental concentrations calculated from the crystalline compositions using Rietveld refinement of the three sintered ore samples were also in good agreement with the certified values and those from X-ray fluorescence analysis. A calibration curve method and a diffraction–absorption method for crystalline phase quantitation were used to validate the results of the powder XRD/Rietveld method, and the three results agreed well. The present method enables reliable determination of not only the major crystalline phases but also the amorphous phase present in the sintered ore.