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USGS · 70233561

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

Robert W. Potter·Scott Babcock·David L. Brown
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Abstract

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+0.0072 t +0.000106 t 2 ±0.05 weight percent NaCl weight percent KCl=27.839+0.0794 t +0.000027 t 2 ±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.

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Robert W. Potter, Scott Babcock, David L. Brown. 1977. A new method for determining the solubility of salts in aqueous solutions at elevated temperatures. https://pubs.usgs.gov/publication/70233561

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