The obtained results have been compared with the most popular relations, such as Tsonopoulos and Meng – Duan correlations. (2011), Saffari – Zahedi (2013), Soave – Redlich – Kwong original form (1972), Ozokwelu – Erbar (1987), Soave (1993) and Nasrifar – Bolland (2004) are coupled with different cubic equations of states including Peng – Robinson (PR), Soave – Redlich – Kwong (SRK), volume – translated Peng – Robinson (VTPR), volume translated Soave Redlich-Kwong (VTSRK) and Patel ‒ Teja ‒ Valderrama (PTV). In this direction, eight different alpha functions, α(Tr), including Peng – Robinson original form (1976), Coquelet et al. In this work, capability of different alpha functions, α(Tr), in prediction of supercritical properties of different polar and nonpolar fluids at Boyle temperature is investigated. The Boyle temperature is the temperature at which the second virial coefficient becomes zero. The dependency of the reduced Boyle temperature (TB / TC) as functions of the Pitzer's acentric factor (ω), hydrocarbon chain length (NC) and the reduced dipole moment (μR) has been also studied. The results show that PR, VTPR and PTV have lower average temperature difference between EoSs and Tsonopoulos or Meng – Duan correlations. For better understanding, the second virial coefficient and the Zeno line (unit compressibility) are also calculated and compared with the available experimental data. The obtained results are compared with the results of other known correlations published so far, such as Tsonopoulos, Meng – Duan and Estrada – Torres et al. The Boyle temperature is calculated for different polar, non – polar and associating substances including alkanes, cycloalkanes, alkenes, aromatics, ethers, esters, ketones, refrigerants, halogens, amines and water. In this regard, the Peng - Robinson (PR), Soave – Redlich – Kwong (SRK), volume – translated Peng – Robinson (VTPR), volume – translated Soave – Redlich – Kwong (VTSRK) and Patel – Teja – Valderrama (PTV) equations of state are used. In this study, the Boyle temperature of 174 substances are predicted using the cubic and volume – translated cubic equations of state. Although initially they were obtained for the van der Waals equation, they have appeared to be valid for the real substances and models described by completely different equations of state. The other regularities concern to the lines of the ideal enthalpy, the enthalpy minima and the isothermal compressibility maxima. The relation for the saturation pressure has been obtained on the basis of this correspondence. Besides, there is projective transformation between the linear elements of the lattice gas phase diagram and that of the continuous systems. The latter relations have allowed us to estimate the critical points of metals, which can not be measured up to now. gives rise to the general equation for the liquid binodalīranch and the universal correlation between the critical and the Zeno-line parameters. The first of them-the line of the unit compressibility factor or the Zeno-line It is also surprising that the thermal expansion coefficient for ethanol takes the minimal value at T ≈ − 4 0 C.Regarding the universal lines on the density-temperature plane are described. As a result at the temperature T ≈ 4 0 C the specific volume of water takes minimal value. It had been shown that the thermal expansion coefficient for water practically linearly diminishes for T → T tr, near T ≈ 4 0 C it becomes equal to zero and takes negative values for T tr < T < 4 0 C. Only near the terminate points – triple and critical ones – the influence of H-bonds becomes determinative. Corrections caused by H-bonds and hydrophobic interactions do not exceed (4 ÷ 5)%. As a result they lead to the similarity of their specific volumes and thermal expansion coefficients practically for all their liquid states. It is taken into account that noted above thermodynamic properties are mainly determined by the averaged interparticle potentials, having the argon-like form. In order to understand better the influence of H-bonds and hydrophobic interaction we compare their dependences with those for argon and hydrogen sulphide. The work is devoted to the analysis of the temperature dependences for the specific volumes and thermal expansion coefficients for water as well as methanol and ethanol belonging to the methanol series.
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