Abstract:With vanadium titano-magnetite concentrate as raw material, K2SO4 is the optimum roasting additive confirmed by experiment. Vanadium leaching rate is 75.54% with 30 percentage points higher than that of blank roasting under the same optimum conditions including dosage of K2SO4 of 4%, roasting temperature of 900 ℃, roasting time of 1 h, leaching temperature of 95 ℃, leaching of 1.5 h, sulfuric acid volume concentration of 15%, and L/S of 3 (mL/g). XRD and SEM analysis show that K2SO4 can obviously destroy structure of vanadium-bearing minerals and promote formation of soluble potassium vanadate, which greatly improves leaching rate of vanadium.