Enhancing effect of vanadium releasing efficiently from lattice in black shale by thermal activation

With the increasing demand for vanadium, the extraction technology of vanadium from strategic black shale has been widely valued. Vanadium mainly exists in muscovite of shale, and the extraction of vanadium requires the consumption of a large amount of acid. In industry, thermal activation is usually used to promote the dissolution of vanadium from muscovite. But the enhancing effect of thermal activation for releasing vanadium from lattice is unclear. In this study, the phase transition of black shale after thermal activation was described. Then the difference in lattice dissolution and vanadium migration were analyzed by quantum chemical simulations. From the atomic level, thermal activation caused a lattice expansion of vanadium-bearing muscovite (VM) through dehydroxylation reaction. Moreover, thermal activation can promote the replacement of K+ by H+, the removal of structural oxygen of tetrahedron and the coordination reaction of F- with central vanadium of octahedron in the acid leaching process. [Display omitted]