The Production of High-Purity Niobium Oxide from Pyrochlore-Perovskite Concentrate

CIM Bulletin, 1965

F. J. Kelly Scientific Officer ; W. A. Gow Head, Hydrometallurgy Section Extraction Metallurgy Division, Mines Branch, Dept. of Mines & Technical Surveys, Ottawa, Ont.

A chemical process, based on laboratory investigations, is proposed for the production . of high-purity niobium oxide from a pyrochlore-perovsk1te flotation concentrate produced from ore obtained at the Oka, Quebec, property of Columbium Mining Products Limited. The method developed included the decomposition and dissolution of the flotation concentrate with hot, concentrated sulphuric acid. The dissolved niobium was purified and concentrated by a solvent extraction step, using methyl isobutyl ketone as the extractant. The niobium was recovered from the extractant with ammonium fluoride solution from which niobium oxide was precipitated with ammonia. Finally, the filtered and washed precipitate was calcined. Ninety-six per cent of the niobium was recovered in a product analysing 99.9 per cent Nb2O3_. The reagent cost was in the range of $1.00 to $1.25 per pound of niobium recovered.
Keywords: Acid, ammonium fluoride, liquid-liquid extraction, methyl isobutyl ketone, Niobium Concentrate, sulphuric acid, Concentrate, Concentrates, Decomposition, Extraction, Niobium, Operation, STEPS, test, Tests