METHOD FOR EXTRACTING VANADIUM FROM VANADIUM SLAG BY ROASTING WITH A COMPOSITE BASED ON CALCIUM AND MANGANESE Russian patent published in 2023 - IPC C22B34/22 C22B7/04 C22B1/04 C22B3/04 

FIELD: vanadium recovery.

SUBSTANCE: present invention relates to the recovery of vanadium from vanadium slag by roasting with a calcium manganese composite. Compounds containing calcium and manganese as additives are mixed with fine powder of vanadium slag. Roasted at a temperature of 750-1000°C for 30-240 min, cooled to a temperature below 600° with obtaining clinker. The primary leaching of clinker is carried out at a temperature of 30-60°C, at W:T 2-4:1, pH 2.5-3.0 to obtain a primary vanadium-containing leach product and primary leach tailings. The secondary leaching of primary leaching tailings is carried out at a temperature of 30-60°C at W:T 1-3:1 and a pH value of 0.5-2.0 to obtain a secondary vanadium-containing leach product and secondary leach tailings. Concentrated sulfuric acid is added to the primary vanadium-containing leaching product, the pH value of the resulting solution is adjusted to 1.5-2.2, heated to a temperature of 80-100°C, kept for 30-120 min, filtration is carried out to obtain hydrated vanadium pentoxide and subsequent melting of hydrated vanadium pentoxide is carried out to obtain flocculent vanadium pentoxide. The molar ratio of the sum of Ca and Mn in a mixture containing calcium and magnesium to V in fine powder of vanadium slag is 0.5-1.5:1, and the molar ratio of Ca to Mn is 1-2:1.

EFFECT: increase in the overall degree of vanadium leaching.

7 cl, 4 dwg