Technology Of Extraction And Kinetics Of Leaching Vanadium From Vanadium Titanium Magnetite Tailings

There are quite abundant vanadium titanium magnetite resources in Panzhihua. Vanadium titanium magnetite is a kind of multi-elements-coexistent iron ore which mainly contain iron, vanadium, and titanium. Vanadium titanium magnetite provide 88 % of the source in vanadium extraction. Traditional technology of vanadium extraction from vanadium titanium magnetite is not only in low recovery rate but also lead to environmental pollution and waste of resources. Based on previous accomplishment of other researchers a new non-pollution roasting and high recovery technology of extracting vanadium was presented in this paper.The vanadium extracting technology from vanadium-titanium-magnetite tailings was studied detailed using single-factor conditional experiment.The various factors affecting the leaching rate of vanadium were investigated in the process of roasting and leaching. SEM method, XRD method and the predominance diagram of dissolved species of V-H2O system were used in analyzing the reaction mechanism of roasting and leaching progress. The best preparation technology of clinker were: mineral size: 200 meshes; additive content: 8 % CaCO3; roasting temperature: 900℃; roasting time: 3 hours. The best extracting technology conditions were: solid-liquid ratio: 1:3; leaching solvent: 30 % H2SO4; leaching temperature: 95℃; leaching time: 4 hours. After being treated by the best preparation technology and extraction technology in above, the extracting rate of vanadium can reach up to 81.87 %.The kinetics of leaching vanadium from vanadium titanium magnetite tailings was also investigated. Results show that the leaching process can be simulated with a shrinking core model 1-(1-R)1 3= kt . The activation energy is 48.31 kJ·mol-1, calculated by the Arrhenius equation from a series of lnk~1/T diagrams under different temperature. The results of kinetic analysis of the leaching data under various experimental conditions indicated a reaction controlled in the leaching progress. The following rate equation was established:The cost accounting shows that there is considerable economic benefit in the roasting-leaching with sulfuric acid technology of vanadium extraction from vanadium-titanium magnetite tailings. The profit will be 30 thousands Yuan for producing one ton of V2O5 . This technology cause little loss of titanium, which is beneficial to comprehensive utilization of mineral resources.