Low-Energy Feasibility for Leaching an Indigenous Scheelite Ore for Industrial Applications

In recent times, the increasing demand for pure tungsten and its compounds in defense, medicine, high technology, and emerging innovations due to its excellent properties such as its tensile strength, corrosion resistance, and high modulus of elasticity cannot be overemphasized. In this study, an acid leaching route was adopted for the extraction of pure tungsten from a Nigerian scheelite ore consisting primarily of scheelite (Ca4.00W4.00O16.00: 96-900-9627) and quartz (Si6.00O6.00: 96-900-5019). At optimal leaching conditions (2.5 mol/L HCl, 70 °C, < 75 µm), 88.5% of the initial 10 g/L ore reacted within 120 min. The low apparent activation energy (Ea) estimated as 22.94 kJ/mol with the reaction order of 0.96 affirmed the dissolution reaction to occur through the diffusion control mechanism of the first-order relation. The low Ea obtained further supports the feasibility and eco-friendly dissolution process as ⁓11.5% of the undissolved materials analyzed to contain silica (SiO2: 96-900-5302) could be used as raw materials for some defined industrial applications.