Saturated Liquid Mixtures Research Articles

Experimental molar volumes for some LNG-related saturated liquid mixtures

Abstract Miller, R.C. and Hiza, M.J., 1978. Experimental molar volumes for some LNG-related saturated liquid mixtures. Fluid Phase Equilibria, 2: 49–57. Saturated (orthobaric) liquid molar volumes are reported for some methane-rich mixtures containing ethane, propane, isobutane, normal butane and nitrogen at temperatures between 100 and 115 K. These data were obtained with a gas-expansion system calibrated against pure methane orthobaric liquid molar volumes. Comparisons are shown between the experimental molar volumes and the results of some recent calculational methods. Discrepancies between experimental and calculated values are all within ± 0.15 percent. The more accurate correlations generally predict the molar volumes within ± 0.1 percent.

Isothermal enthalpy difference for saturated liquid mixture via isobaric Gibbs‐Duhem equation

Isothermal enthalpy difference for saturated liquid mixture via isobaric Gibbs‐Duhem equation

Vapor‐liquid equilibria at high pressures: Calculation of partial molar volumes in nonpolar liquid mixtures

AbstractThermodynamic analysis of high‐pressure vapor‐liquid equilibria requires information on the effect of pressure on liquid phase fugacities; this information is given by partial molar volumes in the liquid mixture. A method for predicting these partial molar volumes is presented here. First, molar volumes of saturated liquid mixtures are computed by extending to mixtures the corresponding states correlation of Lyckman and Eckert. These mixture volumes are then used to calculate partial molar volumes with an expression based on a modification of the Redlich‐Kwong equation. At high pressures partial molar volumes are strong functions of the composition and in the critical region, may be positive or negative. Calculations are sensitive to the characteristic energy between dissimilar molecules; this energy is generally lower than that given by the geometric‐mean rule. Calculated results are in good agreement with experimental data for seven systems containing paraffinic and aromatic hydrocarbons, carbon dioxide, and hydrogen sulfide.

Theorem of corresponding states applied to saturated liquids and vapors

AbstractThe existence of a single generalized compressibility‐factor relationship for univariant systems has long been denied because reduced variables do not provide a generalized vapor‐pressure relationship. The present study demonstrates that a saturation curve depends on the ability of the theorem of corresponding states to correlate the reduced temperature as a function of reduced, pressure and the critical compressibility factor. Saturation curves for both the liquid and the vapor phases are established from compressibility data on a variety of systems, substantiating this conclusion.The compressibility factors of saturated mixtures are correlated with pseudoreduced properties based upon Kay's pseudocritical concept. The results indicate that the compressibility factors of saturated liquid mixtures can be predicted with reasonable precision over the entire two‐phase region. For pseudoreduced isotherms of unity and above, the same isotherms apply to both phases and are approximately consistent with published compressibility charts for pure gases.