An improved volume-translated SRK EOS dedicated to more accurate determination of saturated and single-phase liquid densities

Abstract

Volume translation (VT) has been widely utilized to improve the liquid density (or volume) prediction by cubic equation of state (CEOS). Previous VT-models do not fully exploit the potential of distance function and there is still a room for improving the prediction accuracy of saturated and single-phase liquid densities by CEOS. In this study, we propose an improved volume translated Soave-Redlich-Kwong (VT-SRK) EOS to achieve more accurate volumetric calculations for various pure substances. The overall average absolute percentage deviations of the saturated and single-phase liquid molar volumes yielded by this VT-SRK EOS for 56 compounds are 0.61 and 0.84, respectively; these two errors are obviously lower than the counterparts provided by Abudour et al.'s VT-Peng-Robinson EOS (2012). A fairly good generalization of the fluid-dependent VT parameters can be achieved for hydrocarbons. Moreover, we extend the proposed VT-SRK EOS to mixtures through conventional mixing rules, finding that the proposed VT-SRK EOS provides reliable volume predictions for the hydrocarbon mixtures examined in this study.