The effect of aqueous sulphate on basaltic glass dissolution rates

Steady-state dissolution rates of basaltic glass were measured in mixed-flow reactors at 50 degrees C at pH 3 and 4 as a function of aqueous sulphate concentration. Dissolution rates in the presence of 0.1 moles/kg SO42- Were found to be similar to 3 times greater than those in corresponding SO42- free solutions. This rate increase is found to be approximately consistent with that calculated using a rate equation previously proposed by Gislason and Oelkers (2003). These results suggest that the addition of sulphate to injected CO2 may facilitate CO2 sequestration in basalts by accelerating basaltic glass dissolution rates thus More rapidly releasing aqueous Ca and Mg to Solution.