Thermodynamic properties of supercritical fluids and their mixtures at very high pressures

Abstract

Experimental and estimated PVT data for simple fluids at very high pressures have been correlated with corresponding states theory. Generalized tables and charts are given for density, enthalpy, fugacity, and internal energy for the reduced temperature range 1 to 50 and for reduced pressures to 2000. Consideration is given to possible solidification at very high pressures and to applicability of the reduced charts to quantum fluids, water and ammonia, through temperature‐dependent effective critical constants. The van der Waals two‐fluid model of binary mixtures is used to calculated properties of mixtures including the composition of coexisting phases. The correlations presented here are useful for estimating thermodynamic properties at very high pressures.

Pyrolysis of 1,3‐butanediol as a model reaction for wood liquefaction in supercritical water

“…The fugacity coefficient of pure water at 'Thermochemical data for /,3-butanediol were from Dauben and Tanner (1985). Values of A H : 9 ' and c,, for 3-butene-1-01 were estimated by the method of Benson (1676); 698 K and 23.5 MPa is approximately 0.78 (Breedveld and Prausnitz, 1973), and the fugacity coefficient of water in the 0.01 m.f. butanediol solution would be similar in magnitude, hence the dehydration reaction would be almost complete at equilibrium even at 23.5 MPa.…”

The physicochemical dynamics of carbonatization of the rocks of lithospheric mantle beneath the Siberian Platform

“…The pressure dependences of the thermodynamic characteristics of gases were calculated based on the modified (Lee and Kesler, 1975) Benedict-Webb-Rubin state equation. In the high-pressure zone, the deviation of a mixture of real gases from the ideal state is calculated based on the van der Vaals equations modified by D. Berthelot (Walas, 1985) and in (Breedveld and Prausnitz, 1973). The fugacity coefficients and the molar volumes of the gases were calculated based on the two-(Breeveld and Prausnitz, 1973) and three-parameter (Lee and Kesler, 1975) state equations.…”

Physicochemical modeling of formation of Ag–Au–Hg solid solutions: Kyuchyus deposit (Yakutia, Russia) as an example

“…The dependence of thermodynamic characteristics of gases on pressure was calculated from modified Benedict-Webb-Rubin state equation (Lee and Kesler, 1975). In the high pressure zone a deviation from ideal gas mixture for real gases is calculated using modification Van der Waals equation (Walas, 1985) and (Breedveld and Prausnitz, 1973). Fugacity coefficients and mole gas volumes were calculated using the two-parameter (Breedveld and Prausnitz, 1973) and three-parameter (Lee and Kesler, 1975) equations of state.…”

“…In the high pressure zone a deviation from ideal gas mixture for real gases is calculated using modification Van der Waals equation (Walas, 1985) and (Breedveld and Prausnitz, 1973). Fugacity coefficients and mole gas volumes were calculated using the two-parameter (Breedveld and Prausnitz, 1973) and three-parameter (Lee and Kesler, 1975) equations of state. Mixing models and the binary interaction parameters in the calculations were not considered.…”