A new method for determining the solubility of salts in aqueous solutions at elevated temperatures

A new method for measuring the solubility of simple salts in water at elevated temperatures involves heating assemblages of salt crystals plus solution vapor at a constant rate in a platinum-lined bomb. The dissolution of the last salt crystal is evidenced by a distinct discontinuity in the pressure-temperature curve. Studies of the solubilities of NaCl and of KC1 in water yielded equations expressing the solubility as functions of temperature, t in °C, at the vapor pressure of the solutions as follows:

weight percent NaCl=26.218+0.0072t+0.000106t²±0.05 weight percent NaCl

weight percent KCl=27.839+0.0794t+0.000027t²±0.10 weight percent KCl

The NaCl and KC1 data were measured over the temperature range 148° to 425°C and 148° to 371°C, respectively. However, the equation for NaCl appears to be valid over the range 0° to 800°C, and the KC1 equation appears valid over the range 100° to 450°C.