Extraction of Vanadium from High Calcium and High Phosphorus Vanadium Slag by Magnesiation Roasting-Acid Leaching

Magnesiation roastingMagnesiation roasting-acid leaching is carried out to extract vanadiumVanadium from high calcium and high phosphorus vanadium slagHigh calcium and high phosphorus vanadium slag (HCPVS). The effects of roasting and leaching conditions on vanadiumVanadium and phosphorus extraction are studied. In optimal conditions, the extraction efficiency of vanadiumVanadium reaches 79.7%, and only 35.6% of phosphorus is leached owing to Mg2+ inhibiting the leaching of phosphorus. The roasting mechanism is analyzed by XRD and BSE-EDS systematically, best of the vanadiumVanadium in V-spinel is converted into vanadate, and a small part of vanadiumVanadium is dissolved into Ca2SiO4CaSiO–Ca3(PO4)2 and CaTiO3CaTiO phase. This work reveals the influence mechanism of Ca2SiO4CaSiO–Ca3(PO4)2 and CaTiO3 phase on vanadium extractionVanadium extraction, providing new insights for vanadium extractionVanadium extraction from HCPVS.