Tantalum Production

The most of produced tantalum is obtained from pyrochlore and tantalite-columbite concentrates, which are separated from tin smelting slag by gravitation and flotation methods as well as via electromagnetic and radiometric separation. Ta₂O₅ and Nb₂O₅ concentrations after enrichment reaches 50%. Concentrates and slags are processed until Ta₂O₅ or K₂TaF₇, from which tantalum metal is produced. Concentrates and slags are leached by hydrofluoric acid with following refining. Niobium and tantalum are separated by extraction using tributyl phosphate, cyclohexanone or hexone, or, more rare, another extragent. Tantalum hydroxide is precipitated from aquatic phase by hydrous NH₃; after that it is roasted until Ta₂O₅ or K₂TaF₇ is precipitated using KF.

In chloride way concentrate is mixed with coal or coke, briqueted after which briquettes are chloridized in shaft furnace at 700-800°C. The produced volatile tantalium and niobium pehtachloides condensate, are separated and rectificated. Ta₂O₅ is obtained from TaCl₅, Tantalum hydroxide residuum is roasted.

In sulphate way concentrates are treated y concentrated H₂SO₄ or its mixture with (NH₄)₂SO₄ at 150-300°C, the sulphates are water leached, residuum is separated, Tantalum and Niobium extracted from fluoride media, with following Ta₂O₅ or K₂TaF₇ extraction.

Tantalum metal is produced from K₂TaF₇-Ta₂O₅-KF-KCl fusion by sodium thermal reduction.

A sol of tantalum has been prepared by sparking tantalum electrodes immersed in isobutyl alcohol using an induction coil. The sol appears brownish-black by transmitted light and black by reflected light; it keeps only for one to two weeks