Optimizing methanesulfonic acid leaching for efficient extraction of magnesia from a Nigerian antigorite-rich dolomite ore

Dissolution of a Nigerian antigorite-rich dolomite ore in methanesulfonic acid (MSA) solution for its optimal industrial application was investigated. The impact of the acid concentration, reaction temperature, particle diameter as well as reaction time on the rate of the ore dissolution was examined. The magnesium recovery was 97.2% at the optimal conditions: 2.5 mol/L MSA, solid/liquid 10 g/L, 56 µm in 2 h, and reaction temperature of 75 ºC. According to the shrinking core model, test results indicated that mass diffusion was the controlling step of the overall reaction kinetics. The activation energy of 11.26 kJ mol⁻¹ gives support to this assertion. The correlation coefficient value of (⁓0.98) indicates that the workability of the proposed kinetic model is highly effective or functional. At optimal conditions, a high-purity MgO product was obtained.