About
The H2O-CO2-NaCl is the most representative water-gas-salt system, whose phase behavior, chemical properties and volumetric properties varies with temperature and pressure due to the variations of molecular behavior. For example, NaCl is almost fully ionized at room temperature, but it gradually becomes associated when temperature reaches above 573K. Therefore, we have to take different approaches for different temperature ranges to model various thermodynamic properties (solubility of gas, liquid-vapor phase equilibrium, speciation equilibrium, hydrate formation condisitions, density etc. ) of this system. Right now we have developed models from 273K to 523K and from 593K to about 1273K, but still we don't have reliable models between 523K to 593K. Questions can be directed to: duanzhenhao@yahoo.com.
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TP Coverage and PhaseDiagram
Temperature: 273-523K, 593-1273K; Pressure: 1-2000bar.
References
1. Duan ZH. and Sun R. (2003) An improved model calculating CO2 solubility in pure water and aqueous NaCl solutions from 273 to 533 K and from 0 to 2000 bar. Chem Geol. 193(3-4), 257-271.
2. Duan ZH., Sun R., Zhu C., and Chou I. M. (2006) An improved model for the calculation of CO2 solubility in aqueous solutions containing Na+, K+, Ca2+, Mg2+, Cl-, and SO42. Marine Chem. 98(2-4), 131-139.
3. Sun R. and Duan ZH. (2005) Prediction of CH4 and CO2 hydrate phase equilibrium and cage occupancy from ab initio intermolecular potentials. Geochimi. Cosmochimi. Acta. 69(18), 4411-4424.
4. Li DD. and Duan ZH. (2006) The speciation equilibrium coupling with phase equilibrium in the H2O-CO2-NaCl system from 0 to 250 ˇăC and from 0 to 1000 bar. Submitted to Chem Geol.
5. Hu JW., Duan ZH., Zhu C., and Chou I. M. (2006) PVTx Properties of the CO2-H2O and CO2-H2O-NaCl systems below 647K: Assessment of experimental data and thermodynamic models. Accpeted by Chemical Geology.
© 2006 copyright by Zhenhao Duan Research Group, Institute of Geology and Geophysics, Chinese Academy of Sciences. All rights reserved.