摘要 |
<p>Vanadium-bearing material containing alkaline-earth metal compounds is roasted, say at 1500-1700 DEG F., to form water-soluble alkaline-earth metal vanadates, and quenched in water to bring the vanadates into solution. Preferably the quenched material is ground in the quenching liquid. The quench residue is leached with sulphuric acid to extract remaining vanadium, and the acid liquor and quench liquor finally mixed and heated to precipitate the vanadium as oxide. If calcium sulphate is present, addition of the acid liquor until the mixed liquors are slightly acid precipitates it, and after its removal mixing is completed.</p> |