Extraction of heptafluorotantalate from fluoride- sulphuric acid solutions
Laboratory investigations and experiments on solvent extraction of tantalum from fluoride-sulphuric acid solutions using octanol-1 have been presented. Conditions for precipitating high-purity potassium heptafluorotantalate (PFT) from tantalum re-extracts have been determined. A flowsheet has been developed for the processing of metallic tantalum-bearing wastes with the production of PFT, with optimal regimes for individual process stages. The 500 kg of high-quality PFT accumulated during the testing have been used to produce high-capacity, high-quality tantalum powders for advanced capacitor making.