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Liquid-vapor relations in the critical region of the system NaCl-H 2 O from 380 to 415°C: A refined determination of the critical point and two-phase boundary of seawater

James L. Bischoff·Robert J. Rosenbauer
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Abstract

Pressure-temperature-composition ( P - T - x ) relations for coexisting vapor and liquid phases in the system NaCl-H 2 O were determined experimentally in the critical region from 380 to 415°C. The results provide much improved control on the P - T - x critical line in this region. The critical point of seawater (3.2 wt% NaCl solution), which is bracketed in the present study, is at 407°C and 298.5 bar. In addition, the P - T two-phase boundary of seawater was re-determined. These results provide increased precision and accuracy for theoretical models of critical phenomena in this important two-component system and of the limiting P - T conditions of seawater in seafloor geothermal systems.

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Geochimica et Cosmochimica ActaArticle

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James L. Bischoff, Robert J. Rosenbauer. 1988. Liquid-vapor relations in the critical region of the system NaCl-H 2 O from 380 to 415°C: A refined determination of the critical point and two-phase boundary of seawater. https://doi.org/10.1016/0016-7037(88)90192-5

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