Composite Leaching Agent Leaching Stone Coal Vanadium And Vanadium In Mineral Distribution

Vanadium is a strategic metal. At present, Vanadium consumption around the world exceed 100,000 tons, according to forecast, it will be close to 150,000 t in 2020. Vanadium is a kind of decentralized element without separate minerals in the earth's crust. Stone coal is extremely rich reserves which contain vanadium resources, their mineral composition and distribution of vanadium complex. Over the past few decades Na-roasting-leaching, calcification roasting-carbonate leaching, oxidation roasting-leaching, oxygen pressure acid leaching process used to extract the vanadium. Na-roasting-leaching process due to the high pollution and little metal recovery in recent years has been limited. Other pressures have developed in environmental protection and metal recovery, but have their own shortcomings, especially in adaptability and stability.Leaching is considered to be the key link of the extraction vanadium from stone coal. In this paper, The system of sulfuric acid+infusion X1+oxidizer X2 were chosen to leach the vanadium from the stone coal in Guizhou province, Hunan province, Gansu province and Sichuan province, the stone coal from Hunan province contain Oxide Ore and rude ore.The analysis of stone coal on composition, phase and morphology showed that vanadium in stone coal from Guizhou is relatively low and muscovite more, calcium in stone coal from Hunan surpass 5% and rude ore rich in organic matter, the stone coal from Gansu involve high content of illite, Content of organic matter in the stone coal from Sichuan Approach 32% and silicate-containing vanadium was wrapped by organic matter. The factors experimental results indicate that the leaching rate of vanadium from Guizhou and Hunan incease along with the acid concentration, X1 concentration, leaching temperature, leaching time and other factors strengthen. In the best conditions, the leaching rate exceed 80%.Vanadium leaching rate of Gansu stone coal have the same trend, but in the same conditions, the leaching rate is only about 55% and significantly lower than Guizhou and Hunan stone coal.The leaching rate of Sichuan stone coal under 65% increas when main factors strengthened, if over 65%, There is no way to make it improve in the system of sulfuric acid+infusion X1+oxidizer X2. The results above proove that effects of leaching in the systerm are unstable.In order to better understand the distribution of vanadium in stone coal, the method of fractional measurement of rare elements used in sedimentary was frist applied to study the distribution of vanadium in stone coal. The results showed that vanadium in silicate minerals are more than 60%, vanadium in the adsorption less than 5%, and vanadium in other material phase is different due to the different property of stone coal. The results of Vanadium distribution analysis and the leaching certify that vanadium in stone coal occurs mainly in silicate, but the silicates have deiffrence property. The leaching effect of the composite leaching systerm don't depend on grade of vanadium,calcium and carbon in stone coal, but also the property of silicate-breaing vanadium.