Vapor Liquid Equilibria And Excess Enthalpies For The Association Systems

The recent development in excess properties for alcohol-containing systems was reviewed, especially on simultanious calculation of Vapor liquid equilibria (VLE) and excess enthalpies (HE) data.Based on the association solution theory, a temperature—dependent association model(TDAM) was established to describe the excess enthalpiesfor the alcohol—containing systems. The results of 95 sets of HE datafor the alcohol-conaining systems correlated by TDAM give better agreementwith experimental data than those by the QCSM, WILSON and WC model. BYinterpolating the HE data of two temperatures, the HE data for the othertemperatures and VLE data of low pressures can be predicted by.TDAM. The agreement between the predicting and experimental data is satisfactory.Starting from the generalized van der Waals partition funtion theory,a new equation of state(New EOS) is developed for the thermodynamic properties of polar and nonpolar fluid and their mixtures, include heatsof vaporization, pressure—volume—temperature relations and excess properties.We have adopted the hard sphere potential energy derived by Carnahan and Starling to repulsive force item and the dispersive and the chemicalassociation energy to attractive force item respectively. Appropriateexpressions for the dependency of the a and volume—translated item ontemperature are selected for New EOS. New EOS has been used to correlatethe P—V—T behavior of some 47 substances, including hydrocarbons, ketones,alcohols, acids and aldehydes. The overall average abso-...