Processes for the extraction and production of tantalum

This paper reports on tantalum's density, oxygen affinity, high melting point, and chemical similarity to niobium that have significantly influenced the extractive metallurgical processes. These processes are discussed in terms of concentration and extraction, metal production, and capacitor fabrication. Gravity methods of beneficiation are very effective for the concentration of tantalum minerals because of its high density. Dissolution of tantalum- containing materials requires the use of hydrofluoric acid to avoid the formation of oxides. Because tantalum always occurs with niobium and both have a very similar chemistry, efficient separation requires solvent extraction with MIBK. Tantalum's high melting point has necessitated sintering or vacuum arc-melting to produce and consolidate it to a pure metal. Improvements in the industry have come from the ability to process lower grade materials, improved separation technology, and through the production of higher purity metals