Niobium Extraction from Columbite-tantalite Ore Processing: Gravimetric and Magnetic Methods

The mining of niobium, a strategic metal utilized in the production of high-performance alloys, remains underdeveloped in certain geological contexts despite its potential. In this study, columbite-tantalite ore was utilized as a raw material to investigate methodologies for the physical concentration of niobium. To this end, two fractions of columbite-tantalite ore were prepared: one crushed to 2 mm and the other ground to 250 µm. Following a comprehensive characterization of the ore, the various concentration steps were applied sequentially. Each concentrate was analyzed to evaluate mass yields, metallurgical yields, and enrichment rates. The findings suggest that the integration of methodologies results in a substantial enhancement in niobium concentration, with metallurgical yields attaining 56.94% for the 2 mm fraction and 50.48% for the 250 µm fraction, and enrichment rates exceeding 2. This outcome validates the complementarity of the implemented processes, notwithstanding the occurrence of losses, particularly in the fines. In conclusion, the study demonstrates the effectiveness of physical concentration methods for initial niobium enrichment. These results pave the way for further valorization of the concentrate obtained by hydrometallurgical methods, enabling the selective extraction and purification of niobium for industrial use.