Thermodynamic excess properties of three alcohol-hydrocarbon systems

Abstract

The thermodynamic functions ACP, , ASí;, and AG£ are presented as functions of temperature over the entire composition range for three binary liquid systems. The pressure dependency of AH, AS£, and AG£ is determined from measurements of AV.1 HE PURPOSE of this paper is to present an extensive correlation of thermodynamic data for the binary liquid systems: ethanol-toluene, 1-propanol-rc-heptane, and 2-propanol-n-heptane. The results presented provide data over a considerable temperature range on the excess heat capacities, enthalpies, entropies, Gibbs free energies, and volumes of three highly nonideal alcohol-hydrocarbon solutions.

Heat capacities and densities of the binary mixtures containing ethanol, cyclohexane or 1-hexene at high pressures

“…For the mixture (cyclohexane + ethanol) the comparison between our experimental density data and the literature [33] are represented in figure 7, where can be seen the good agreement. In figure 8a, the positive values of the excess molar volumes are shown and they are increased with temperature [34] as is expected for a globular molecule [35] and non polar with the ethanol which forms hydrogen bonds. The excess volumes decrease with pressure as the molecule distances and the free volume also decrease [31], as is shown in figure 8b.…”

Thermodynamic study of (heptane+amine) mixtures. II. Excess and partial molar volumes at 298.15K

“…The V°'s of alkanols necessary to obtain DV br are taken from literature [11,[16][17][18][19], while the V°'s of alkanes are unpublished results from our laboratory. A molecule is considered branched also when a functional group is attached to an inner carbon of the alkyl chain, as in sec-butylamine.…”

Excess thermodynamic properties of chainlike mixtures. II. Self-associating systems: predictions from soft-SAFT and molecular simulation

“…This term is expressed as a sum over all the association sites and components of the mixture [66], (7) where n(T(')) is the total number of associating sites of molecules i. X t ) , the fraction of molecules i not bonded at site A, may be written as a mass-action equation [66,761 All the nonzero site-site interactions should be defined a priori in order to solve equation (8). Afk involves a weighted integral over all the orientations and an integration over all separations of molecules 1 and 2, defined as [95, 1071 (9) where g y is the pair radial distribution function of the reference fluid, = exp(Egi,ij/kBT) -1 is the Mayer function of the association potential, and d( 12) denotes an unweighted average over all orientations and an integration over all separations between molecules 1 and 2.…”