Dissolution Behaviors of Minerals in Tellurium–Bismuth Ore During Oxidic–Acidic Leaching

The dissolution behaviors of various minerals in the tellurium–bismuth ore during oxidic–acidic leaching were investigated systematically in this work. The Te–Bi phase in the ore distributes in network shape, triangular shape, tree shape, strip shape, bulk shape, sparse granule, flake shape, crescent, etc., which are closely intercalated with FeS, FeS2, and CaCO3·(Mg,Fe,Mn)CO3. Under suitable conditions, 95.61% Te and 95.77% Bi can be recovered. Within 20 min of the initial leaching, most of dolomite and Te–Bi phase dissolve rapidly. With the extension of leaching time, a large amount of rod-shape CaSO4 particles form, attach on the surface of the tellurium–bismuth ore particles, and then grow and coarsen. The (Mg,Fe,Al)(Si,Al)Ox(OH)y phase dissolves mainly within 60 min. Fe–S phase can be corroded but cannot dissolve completely. SiO2 cannot dissolve at all. Besides, H2SO4 and Fe3+ play a significant role on the dissolution of various minerals in the ore. Without Fe3+ or H2SO4 in immersion liquid, Te and Bi are difficult to be leached into the lixivium from the tellurium–bismuth ore. As H2SO4 concentration and Fe3+ concentration increase, Te–Bi phase and Fe–Mg–Al–Si–O phase gradually dissolve, the Fe–S phase can be corroded obviously but cannot dissolve, and the Si–O phase has no change. The dissolution of dolomite is mainly controlled by H2SO4. The dissolution behaviors of various minerals in the tellurium–bismuth ore during oxidic–acidic leaching were investigated systematically. Most of dolomite and Te–Bi phase dissolve rapidly. A large amount of rod-shape CaSO4 particles form, attach on the surface of the tellurium–bismuth ore particles, and then grow and coarsen. H2SO4 and Fe3+ play a significant role on the dissolution of various minerals in the ore.