Vanadium extraction from stone coal using a novel two-stage roasting technology

Abstract

In this work, a two-stage roasting technology was presented to promote the vanadium leaching efficiency. The effects of roasting factors of two-stage roasting method on vanadium leaching rate and the mechanism of extracting vanadium from stone coal were studied. Phase transformation of minerals during roasting was analyzed with X-ray diffraction (XRD). Microstructure change was studied using scanning electron microscope (SEM), energy dispersive spectrum (EDS) and Brunauer-Emmett-Teller (BET) analyses. The results showed that under the optimal conditions, i.e., first-stage roasting temperature of 650 °C, roasting time of 1 h, air atmosphere and second stage roasting temperature of 950 °C, roasting time of 3 h, 30% oxygen concentration atmosphere, a vanadium leaching recovery of 80.26% was obtained. The results of this study confirmed that the two-stage roasting technology could be a more environment-friendly and effective method for extracting vanadium from stone coal.