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Title: Phase relations in the system NaCl-KCl-H sub 2 O: V. Thermodynamic-PTX analysis of solid-liquid equilibria at high temperatures and pressures

Abstract

The Gibbs energies of mixing for NaCl-KCl binary solids and liquids and solid-saturated NaCl-KCl-H{sub 2}O ternary liquids were modeled using asymmetric Margules treatments. The coefficients of the expressions were calibrated using an extensive array of binary solvus and solidus data, and both binary and ternary liquidus data. Over the PTX range considered, the system exhibits complete liquid miscibility among all three components and extensive solid solution along the anhydrous binary. Solid-liquid and solid-solid phase equilibria were calculated by using the resulting equations and invoking the equality of chemical potentials of NaCl and KCl between appropriate phases at equilibrium. The equations reproduce the ternary liquidus and predict activity coefficients for NaCl and KCl components in the aqueous liquid under solid-saturation conditions between 673 and 1,200 K from vapor saturation up to 5 kbar. In the NaCl-KCl anhydrous binary system, the equations describe phase equilibria and predict activity coefficients of the salt components for all stable compositions of solid and liquid phases between room temperature and 1,200 K and from 1 bar to 5 kbar.

Authors:
;  [1];  [2];  [3]
  1. Lawrence Berkeley Lab., CA (United States)
  2. Geological Survey, Reston, VA (United States)
  3. Virginia Polytechnic Inst. and State Univ., Blacksburg (United States)
Publication Date:
OSTI Identifier:
5035752
DOE Contract Number:  
AC03-76SF00098
Resource Type:
Journal Article
Journal Name:
Geochimica et Cosmochimica Acta; (United States)
Additional Journal Information:
Journal Volume: 56:6; Journal ID: ISSN 0016-7037
Country of Publication:
United States
Language:
English
Subject:
15 GEOTHERMAL ENERGY; 58 GEOSCIENCES; GEOTHERMAL FLUIDS; PHASE STUDIES; THERMODYNAMIC PROPERTIES; EQUATIONS; EQUILIBRIUM; EXPERIMENTAL DATA; FREE ENTHALPY; LIQUIDS; MIXING HEAT; MIXTURES; PHASE DIAGRAMS; POTASSIUM CHLORIDES; SODIUM CHLORIDES; SOLIDS; SOLUBILITY; TEMPERATURE RANGE 0400-1000 K; TEMPERATURE RANGE 1000-4000 K; VERY HIGH PRESSURE; WATER; ALKALI METAL COMPOUNDS; CHLORIDES; CHLORINE COMPOUNDS; DATA; DIAGRAMS; DISPERSIONS; ENERGY; ENTHALPY; FLUIDS; HALIDES; HALOGEN COMPOUNDS; HYDROGEN COMPOUNDS; INFORMATION; NUMERICAL DATA; OXYGEN COMPOUNDS; PHYSICAL PROPERTIES; POTASSIUM COMPOUNDS; SODIUM COMPOUNDS; TEMPERATURE RANGE; 152001* - Geothermal Data & Theory- Properties of Aqueous Solutions; 580000 - Geosciences

Citation Formats

Sterner, S M, Pitzer, K S, Chou, Iming, and Downs, R T. Phase relations in the system NaCl-KCl-H sub 2 O: V. Thermodynamic-PTX analysis of solid-liquid equilibria at high temperatures and pressures. United States: N. p., 1992. Web. doi:10.1016/0016-7037(92)90190-T.
Sterner, S M, Pitzer, K S, Chou, Iming, & Downs, R T. Phase relations in the system NaCl-KCl-H sub 2 O: V. Thermodynamic-PTX analysis of solid-liquid equilibria at high temperatures and pressures. United States. https://doi.org/10.1016/0016-7037(92)90190-T
Sterner, S M, Pitzer, K S, Chou, Iming, and Downs, R T. 1992. "Phase relations in the system NaCl-KCl-H sub 2 O: V. Thermodynamic-PTX analysis of solid-liquid equilibria at high temperatures and pressures". United States. https://doi.org/10.1016/0016-7037(92)90190-T.
@article{osti_5035752,
title = {Phase relations in the system NaCl-KCl-H sub 2 O: V. Thermodynamic-PTX analysis of solid-liquid equilibria at high temperatures and pressures},
author = {Sterner, S M and Pitzer, K S and Chou, Iming and Downs, R T},
abstractNote = {The Gibbs energies of mixing for NaCl-KCl binary solids and liquids and solid-saturated NaCl-KCl-H{sub 2}O ternary liquids were modeled using asymmetric Margules treatments. The coefficients of the expressions were calibrated using an extensive array of binary solvus and solidus data, and both binary and ternary liquidus data. Over the PTX range considered, the system exhibits complete liquid miscibility among all three components and extensive solid solution along the anhydrous binary. Solid-liquid and solid-solid phase equilibria were calculated by using the resulting equations and invoking the equality of chemical potentials of NaCl and KCl between appropriate phases at equilibrium. The equations reproduce the ternary liquidus and predict activity coefficients for NaCl and KCl components in the aqueous liquid under solid-saturation conditions between 673 and 1,200 K from vapor saturation up to 5 kbar. In the NaCl-KCl anhydrous binary system, the equations describe phase equilibria and predict activity coefficients of the salt components for all stable compositions of solid and liquid phases between room temperature and 1,200 K and from 1 bar to 5 kbar.},
doi = {10.1016/0016-7037(92)90190-T},
url = {https://www.osti.gov/biblio/5035752}, journal = {Geochimica et Cosmochimica Acta; (United States)},
issn = {0016-7037},
number = ,
volume = 56:6,
place = {United States},
year = {Mon Jun 01 00:00:00 EDT 1992},
month = {Mon Jun 01 00:00:00 EDT 1992}
}