A step-wise separation process for niobium and tantalum from tantalite by extraction and ion exchange was developed. A tantalite mineral was dissolved by a fusion technique using ammonium bifluoride as flux. Tantalum and niobium form stable anionic fluoride complexes in fluoride solutions. This fact was used to develop an analytical method to separate tantalum and niobium from other metals within the tantalite mineral and from each other.Tantalum was separated from the rest of the mineral matrix by solvent extraction using methyl isoamyl ketone. The analytical results indicated that 98.9(9)% Ta_2O_5 was recovered from the organic portion while 101.6(3)% Nb_2O_5 and the rest of the elements were recovered from the aqueous solution. Niobium was subsequently separated from the tantalite matrix by anion exchange technique using Dowex Marathon resin and HCl solution as a mobile solvent. The analytical results indicated Nb_2O_5 recovery of 101 (2)%.
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