Vanadium occupation and its leachability differences in trioctahedral and dioctahedral mica

Abstract

Vanadium in black shale is found mainly in aluminosilicate minerals such as mica. Vanadium occupation in mica directly determines the vanadium leaching rate from black shale. The essential difference of leachability is demonstrated on the basis of quantum chemical simulation methods and experimental verification. The results show that the optimal location of vanadium in black shale is most likely in the octahedron of mica whether it is dioctahedral or trioctahedral mica. The simulations of the dissolution process of octahedral layers and the leaching experiments proved that the octahedron in trioctahedral mica was attacked by H⁺ and F⁻ at lower related potential energy than in dioctahedral mica during the structural collapse process. It reflects a key feature of differentiation on the leachability of different mica-type black shale, which can provide guidance for selection of low-consumption leaching technology in actual production on account of structural differences.