SOLUBILITY OF CALCITE IN CO2-H2O SOLUTIONS: 100, 200, 300°C, AND 100, 500, 1000 BARS FROM 0.1 TO 2.3 M/KG CO2

Difficulty in locating Dickson and Berendsen 1968 Geological Society of America abstract on calcite solubility motivated us to call attention to it in session on CO₂ sequestering. Multiple reversed experiments were done in Dickson et al. Teflon reaction cell permeable to CO₂, in which CO₂ concentrations in cell liquid were controlled at constant temperature, T, and hydraulic pressure, P_T. Calcite solubilities in CO₂-H₂O solutions at 200°C and 300°C, 500 bars and 1000 bars, from 0.10 to 2.30 m/kg CO₂. Solubilities rise with increased P and fall with increasing T. Gentle maxima exist at 0.90 m/kg CO₂, 200°C and 1.20 m/kg CO₂, 300°C. Solubilities at 200°C are five fold higher than 300°C. At 1000 bars, listed in °C, mM/kg CaCO3, m/kg CO₂: at 100 - 9.34 in 0.10, 18.5 in 0.80: at 300 - in 0.95, 0.89; in 1.59, 0.80. Studies with P_T equal to or less than partial pressure of CO₂ apply to shallow boiling systems, ours to deep condensed systems. Addendum with tables of data.