Alternative beneficiation of tantalite and removal of radioactive oxides from Ethiopian Kenticha pegmatite-spodumene ores

The beneficiation methods for Ethiopian Kenticha pegmatite-spodumene ores were assessed through mineralogical and quantitative analyses with X-ray diffraction (XRD) and energy-dispersive X-ray fluorescence (EDXRF). The tantalite in the upper zone of the Kenticha pegmatite-spodumene deposit is 58.7wt% higher than that in the inner zone. XRD analysis revealed that the upper zone is dominated by manganocolumbite, whereas the inner zone is predominantly tantalite-Mn. Repeated cleaning and beneficiation of the upper-zone ore resulted in concentrate compositions of 57.34wt% of Ta₂O₅ and 5.41wt% of Nb₂O₅. Washing the tantalite concentrates using 1vol% KOH and 1 M H₂SO₄ led to the removal of thorium and uranium radioactive oxides from the concentrate. The findings of this study suggest that the beneficiation and alkaline washing of Kenticha pegmatite-spodumene ores produce a high-grade export-quality tantalite concentrate with negligible radioactive oxides.