| 摘要 |
PURPOSE:To produce a Ta halide having high purity in high yield, by contacting fluoric acid containing Ta, Nb and impurity metal ion or a liquid mixture of the fluoric acid and sulfuric acid with a specific organic solvent. CONSTITUTION:Fluoric acid containing Ta, Nb and impurity metal ion or a liquid mixture of the fluoric acid and sulfuric acid is made to contact with (A) one or more organic solvents selected from ketone, neutral phosphoric acid ester, alkylamine and amide diluted with petroleum hydrocarbon to effect preferential extraction of Ta and the the solvent A containing Ta is contacted with water or an aqueous solution containing NH3 and HF or K<+> and HF to effect back extraction of Ta. The aqueous solution containing the Ta ion is added with NH3 and NH4OH or KOH and KF to form precipitate containing Ta, F and NH4<+> or Ta, F and K<+>. The Ta-containing extract or the above precipitate is dissolved in an acid such as sulfuric acid, adjusted to a specific H<+> ion concentration and contacted with an organic solvent (B) such as ester or alcohol to extract Ta ion in the form of a metal halide complex. The solvent B is removed from the product to obtain the objective Ta halide.
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