t-mPR状态方程计算高压二元和三元体系的体积膨胀

he volume expansion of the liquid phases for the CO2/acetone and CO2/ethanol binary systems and the CO2/ethanol/water ternary system was investigated using the t-mPR equation of state (t-mPR EoS) and the PR equation of state (PR-EoS). The correlations for the published vapor-liquid equilibrium (VLE) data of the above systems show that both the EoS can provide fairly good VLE calculations for the binary systems, but t-mPR EoS gives slightly better results. The volume expansion prediction for the above systems and the comparison with the published data show that, compared to PR-EoS, t-mPR EoS gives better results for the binary systems and provides more reasonable results around 7.8MPa. Moreover, the calculations indicate that the volume expansion of the CO2/acetone system is always larger than that of the CO2/ethanol system. The volume expansion of the ternary system shows a maximum point corresponding to about the critical pressure (about 7.8 MPa) of the CO2/ethanol mixture; An increase in the content of ethanol can improve the maximun volume expansion and therefore help to enhance the removal of water.