Fluid Phase Equilibria, Vol.108, No.1-2, 167-183, 1995
The Effect of the Molecular Shape on the Enthalpic Behavior of Liquid-Mixtures - Cyclic Hydrocarbons in Heptane and Tetrachloromethane
Excess enthalpies H-E at 298.15 K have been determined by flow microcalorimetry for binary mixtures of heptane or tetrachloromethane+a cyclic hydrocarbon (cycloheptane, cyclooctane, cyclodecane, 1,2,3,4-tetrahydronaphthalene, cis-decahydronaphthalene, trans-decahydronaphthalene, bicyclohexyl). With the exception of tetrahydronaphthalene+tetrachloromethane and of trans-decahydronaphtalene+heptane, all mixtures examined exhibit positive deviations. H(E)s have been analysed in terms of the DISQUAC model. Partial molar excess enthalpies at infinite dilution as well as standard enthalpies of solvation, Delta H-0, have been evaluated for cycloalkanes in the two solvents and compared with those of linear and branched alkanes. The effect of cyclization upon Delta H-0 has been discussed and the contributions to Delta H-0 of the cavity and of the interaction terms have been estimated through the scaled particle theory.
Keywords:EXCESS GIBBS ENERGIES;DECALIN + BENZENE;THERMODYNAMIC PROPERTIES;BINARY-MIXTURES;NORMAL-ALKANE;ORGANIC-COMPOUNDS;2 TEMPERATURES;VOLUMES;298.15-K;CYCLOALKANE