Recovery of uranium, vanadium and fluorine from phosphate ores

Abstract

A process for the recovery of uranium, vanadium and fluorine as byproducts of phosphoric acid obtained via hydrochloric acid (the cheapest locally produced acid) acidulation of phosphate ores was studied. At a redox potential of 180-200 mV, by introducing iron powder into the leaching circuit at 90°C, a relatively small amount of uranium and vanadium residue was obtained. The residue obtained was roasted with sodium chloride at 850°C to produce water-soluble sodium vanadate. Water leaching then removed the vanadium, leaving a uranium residue. The uranium was selectively leached by sodium carbonate at a redox potential of 480 mV. The product was then processed by alkaline decomposition to prepare the sodium diuranate concentrate necessary for uranium processing. Fluorine was recovered during the acid leaching process as sodium fluorosilicate by adding a stoichiometric amount of rock salt or sodium carbonate to the leaching circuit. © 1985.