This communication gives an overview of our study on the dissolution kinetics of thermally activated serpentine (dehydroxylated serpentine). Firstly, we had studied the far-from-equilibrium dissolution kinetics of 75% dehydroxylated lizardite particles in a liquid and gas flow-through reactor at moderate temperatures (30°C < T < 120 °C) and low CO2 partial pressures (0.1 bar < pCO2 < 2 bar). Over 80% of the Mg was leached from the dehydroxylated lizardite particles. We then followed it up by developing a non-steady state dissolution kinetics model. The model uses surface complexation mechanisms to describe the specific dissolution rates. The model was able to describe the evolution of the non-stoichiometric aqueous concentration profiles of magnesium and silica accurately, taking into account the dynamic evolution of the reactor pH at non-steady state dissolution conditions. The kinetic parameters could be used to compare the dissolution performances of differently activated minerals in their application as potential feed materials for an ex situ mineral carbonation process.
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