Poster Number 93
This study modeled experimental conditions for wet mineral carbonation of forsterite (O'Connor et al., 2002). The experimental procedure from that study used a solution of 1.0 molar NaCl and 0.64 molar NaHCO3, and reacted it with forsterite (crushed to 37 μm) at 185°C in the presence of 15 MPa CO2(g). In the modeled system, a similar solution containing sodium, chloride, and bicarbonate ions was reacted with a basalt with CO2 fugacity fixed at 150 bars. CIPW norms calculated for several Nevada basalts served as input basalt mineralogies. Models were run from 0 to 200°C at 25°C intervals for each basalt.
Preliminary results indicate that the amount of carbon sequestered by mineral carbonation is sensitive to temperature. Optimum reaction temperature varies with basalt composition, suggesting each mineral carbonation reaction should have its own optimum temperature based on basalt mineralogy. In the models, carbon is sequestered in four phases: siderite, magnesite, dolomite, and dawsonite. However, relative abundances of carbonate-bearing product minerals vary as a function of reaction temperature and basalt mineralogy.