Temperature and density effects on the high temperature ionic speciation in dilute Na{sup +}/Cl{sup {minus}} aqueous solutions
- Department of Chemical Engineering, 419 Dougherty Engineering Building, University of Tennessee, Knoxville, Tennessee 37996-2200 (United States)
- Chemical and Analytical Science Division, Oak Ridge National Laboratory. Oak Ridge, Tennessee 37831-6110 (United States)
Molecular simulation of dilute NaCl aqueous solutions is performed to study the Na{sup +}/Cl{sup {minus}} ion-pair association and the constant of equilibrium between the solvent separated (shared) and contact ion pairs at high temperature. Using the simple point charge, the Pettitt{endash}Rossky, and the Fumi{endash}Tosi models for the water{endash}water, the ion{endash}water, and the ion{endash}ion interactions, we determine the density dependence of the constants along the {ital T}{sub {ital r}}={ital T}/{ital T}{sub {ital c}}=1.05 isotherm, and the temperature dependence along the {rho}{sub {ital r}}={rho}/{rho}{sub {ital c}}=1.5 isochore. The simulation results for the association constant are then compared with the predictions of two recent correlations based on conductance measurements at high temperature. The outcome of the comparison is interpreted in terms of the microstructural behavior of the solvent around the ions and the realism of its dielectric behavior. {copyright} {ital 1996 American Institute of Physics.}
- Research Organization:
- Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
- DOE Contract Number:
- AC05-96OR22464
- OSTI ID:
- 389275
- Journal Information:
- Journal of Chemical Physics, Vol. 105, Issue 20; Other Information: PBD: Nov 1996
- Country of Publication:
- United States
- Language:
- English
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