Effects of the mineral phase and valence of vanadium on vanadium extraction from stone coal

• Published in: International journal of minerals, metallurgy and materials metallurgy and materials, 2012-10, Vol.19 (10), p.893-898
• Main Authors: Hu, Yang-jia, Zhang, Yi-min, Bao, Shen-xu, Liu, Tao
• Format: Article
• Language: English
• Subjects: Anorthite; Calcium aluminum silicates; Ceramics; Characterization and Evaluation of Materials; Chemistry and Materials Science; Coal; Composites; Corrosion and Coatings; Decomposition; Glass; H2SO4; Leaching; Materials Science; Metallic Materials; Mica; Minerals; Natural Materials; Oxidation; Roasting; Stone; Sulfuric acid; Surfaces and Interfaces; Thin Films; Tribology; Valence; Vanadium; 云母矿物; 分解控制; 浸出率; 烘烤温度; 焙烧温度; 石煤提钒; 矿物相
• ISSN: 1674-4799; 1869-103X
• DOI: 10.1007/s12613-012-0644-9

The influence of roasting on the leaching rate and valence of vanadium was evaluated during vanadium extraction from stone coal. Vanadium in stone coal is hard to be leached and the leaching rate is less than 10% when the raw ore is leached by 4 moUL H2SO4 at 90℃ for 2 h. After the sample is roasted at 900℃ for 2 h, the leaching rate of vanadium reaches the maximum, and more than 70% of vanadium can be leached. The crystal of vanadium-bearing mica minerals decomposes and the Content of V（V） increases with the rise of roasting temperature from 600 to 900℃, therefore the leaching rate of vanadium increases significantly with the decomposition of the mica minerals. Some new phases, anorthite for example, form when the roasting temperature reaches 1000℃. A part of vanadium may be enwrapped in the sintered materials and newly formed phases, which may impede the oxidation of low valent vanadium and make the leaching rate of vanadium drop dramatically. The leaching rate of vanadium is not only determined by the valence state of vanadium but also controlled by the decomposition of vanadium-bearing minerals and the existence state of vanadium to a large extent.