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An equation correlating the solubility of quartz in water from 25° to 900°C at pressures up to 10,000 bars

Robert O. Fournier·Robert W. Potter
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Abstract

The solubility of quartz in water from 25° to 900°C at specific volume of the solvent ranging from about 1 to 10 and from 300° to 600°C at specific volume of the solvent ranging from about 10 to 100 is given by an empirically derived equation of the form: log m = A + B (log V ) + C (log V ) 2 where m is the molal silica concentration, V is the specific volume of pure water, and A = −4.66206 + 0.0034063 T + 2179.7 T −1 − 1.1292 × 10 6 T −2 + 1.3543 × 10 8 T −3 B = −0.0014180 T — 806.97 T −1 C = 3.9465 × 10 −4 T T is temperature in kelvins. The experimental data used in formulating the empirical relation ranged in pressure from 1 bar at 25°C to about 10,000 bars at 900°C, and the lowest pressure in the low-density steam region was about 30 bars. According to the above equation, the average difference in molality between 518 measured and calculated solubilities is −0.016 m with a standard deviation of 0.089.

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Robert O. Fournier, Robert W. Potter. 1982. An equation correlating the solubility of quartz in water from 25° to 900°C at pressures up to 10,000 bars. https://doi.org/10.1016/0016-7037(82)90135-1

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