METHOD FOR PRODUCING REFRACTORY METALS FROM A CONCENTRATE OF LAPORITE

摘要

The inventive method for producing refractory metals from a concentrate of laporite consists in the following: the concentrate of laporite is finely crushed and disintegrated with the aid of concentrated nitric acid at an atmospheric pressure and a temperature exceeding 100 DEG C, followed by the production of a pulp of hydrated cake of refractory metal oxide; said pulp is phosphated in order to produce a fluoride solution of tantalum, niobium and titanium; fluotantalate and fluoniobate acids are extracted from the solution with the aid of octyl alcohol and afterwards re-extracted with the aid of water; the remaining fluotitanate acid is evaporated; the tantalum and niobium oxide are extracted from the fluotantalate and fluoniobate acids, and the titanium dioxide is extracted from the fluotitanate acid by means of high-temperature pyrolysis at a temperature ranging from 600 DEG C to 650 DEG C. The inventive method is characterized by fluorinating the pulp of the hydrated cake by absorbing a gaseous fluorine hydride from furnace gases with the aid of the pulp. Said furnace gases are obtained as a result of high-temperature pyrolysis of the fluotantalate, fluoniobate and fluotitanate acids. For this purpose, the furnace gases and the pulp of the hydrated cake are counter flowed in the recirculating regime of the pulp.