[en] The extraction of tantalum, niobium, titanium, zirconium, tungsten and iron (3) from HF-solutions and HF+HCl mixture by tetraoctylethylenediamine solution in CHCl₃ is studied. An extraction method of tantalum separation from niobium, zirconium, titanium, iron and tungsten has been developed. Optimum conditions - are shown to be 1.2 MHF and 1.0 MHCl. 6%Nb, 2% Zr, Ti, Fe(3) and 4%W transfer to the organic phase under optimum conditions at 0.1 M extraction by tetraoctylethylenediamine. For tantalum quantitative separation the washing of the organic phase by the solution of the same composition is necessary. This method makes it possible to separate tantalum from 50O-fold amounts of Nb, Zr and Ti, 300-fold amounts of Fe and 100-fold amounts of of W. The technique of Ta and Nb determination in the complex composition alloy stantard sample has been developed