<p>Based on the correlation and independence of the leaching behaviors of iron and vanadium, a novel “selective stage leaching” method can be designed. This method can significantly achieve a better selective leaching separation between vanadium and iron. It involves pre-leaching for impurity removal in the first stage and vanadium leaching in the second stage. The iron removal rate reached 44.99% in the first stage of pre-leaching for impurity removal without dissolving vanadium. Then, the relatively pure vanadium solution was obtained when acid leaching of vanadium from the first-stage leaching residue, and the loading of subsequent iron removal process was effectively reduced. In the first-stage pre-leaching for impurity removal, the iron removal rate reached 44.99% without dissolving vanadium. Subsequently, when the first-stage leaching residue was acid-leached for vanadium extraction, a relatively pure vanadium solution was obtained, effectively reducing the load of the subsequent iron-removal process. Thermodynamic analysis of this new leaching method was also conducted. The results indicated that, theoretically, the impurity Fe(II) could be completely leached by acid. When the acid concentration at the leaching equilibrium of the first-stage leaching was 10⁻⁴&#xa0;mol·L^–1, vanadium was not leached by sulfuric acid, providing a theoretical basis for the first-stage pre-leaching for impurity removal. According to the Eh–pH diagram of Fe(III) at dissolution equilibrium, Fe(III) could not be dissolved in the first-stage leaching but entered the second-stage leaching process along with vanadium. Therefore, the vanadium solution obtained from the second-stage leaching still contained some iron ions. Based on the Eh–pH diagram, these iron ions were in the form of Fe(II).</p>