Selective leaching of vanadium from V-Ti magnetite concentrates by pellet calcification roasting-H2SO4 leaching process

A novel method of pellet calcification roasting-H2SO4 leaching was proposed to efficiently separate and extract vanadium (V) from vanadium-titanium (V-Ti) magnetite concentrates. The leaching rate of V is as high as 88.98%, while the leaching rate of impurity iron is only 1.79%. Moreover, the leached pellets can be used as raw materials for blast furnace ironmaking after secondary roasting. X-ray photoelectron spectroscopy (XPS) and scanning electron microscopy with energy dispersive X-ray spectrometry (SEM-EDS) analyses showed that V3+ was oxidized to V5+ after roasting at 1200 °C, and V5+ was then leached by H2SO4. X-ray diffraction (XRD) analyses and single factor experiment revealed a minimal amount of dissolved Fe2O3 during H2SO4 leaching. Therefore, a high separation degree of V and iron (Fe) from V-Ti magnetite concentrate was achieved through H2SO4 leaching. Compared with the traditional roasting-leaching process, this process can achieve a high selectivity of V and Fe, and has excellent prospects for industrial production.