Dissolution kinetics of calcite, dolomite and magnesite at 25 °C and 0 to 50 atm pCO2

The results obtained in this study demonstrate that carbonate mineral dissolution rates are not proportional to H2CO3*(aq) and depend only weakly on pCO2. For dolomite (cleavage planes) and magnesite, the surface complexation model (SCM) of Pokrovsky et al. [Pokrovsky, O.S., Schott, J., Thomas, F., 1999a. Processes at the magnesium-bearing carbonates/solution interface. I. A surface speciation model of magnesite. Geochim. Cosmochim. Acta, 63, 863-880; Pokrovsky, O.S., Schott, J., thomas, F., 1999b. Dolomite surface speciation and reactivity in aquatic systems. Geochim. Cosmochim. Acta, 63, 3133-3143.] predicts dissolution rates up to 50 atm pCO2 with a good accuracy. Because the dissolution of calcite at 3