The recovery of fine hematite particles from banded hematite quartzite (BHQ) ore with potato starch has beeninvestigated using selective flocculation. Microscopic features, coupled with x-ray diffraction (XRD), and Fourier transformsinfrared (FTIR) spectroscopic data provide evidences for adsorption of starch molecules on hematite surface. Thestarch molecules show good selectivity for hematite particles in the pH range of 8.5-9.5 and in the reagent concentrationrange of 20-40 mg/l. The Scanning electron microscope (SEM) studies show that flocs of hematite particles are larger andappear to be denser than that of quartz. Initial results with 1:1 hematite-quartz mixture indicated that it is possibleto achieve an iron concentrate of 64.5% Fe with 92.0% of iron recovery from a feed of 34% Fe. However under opticalconditions of pH and reagent concentration, the BHQ ore could be upgraded from an initial grade of 38.9% Fe to 57.2%Fe with 71% recovery. The overall results indicate that separation of very fine grained hematite present in the BHQ ironore is feasible by selective flocculation.
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