Excess molar volumes of cyclohexanone with n-, sec-, or tert-butylbenzene: Application of the PFP theory and graph-theoretical approach

Abstract

Excess molar volumes, VE, for the binary mixtures of cyclohexanone with n-, sec-, or tert-butylbenzene were measured over the entire composition range at (298.15, 303.15, 308.15 and 313.15) K and 0.1 MPa, by means of a vibrating-tube densimeter. VE data are sigmoid shape for the studied mixtures of cyclohexanone + n-butylbenzene (with negative VE values at lower mole fractions of cyclohexanone) and negative for the mixtures of cyclohexanone + sec-butylbenzene, and cyclohexanone + tert-butylbenzene over the whole composition range. The absolute values of excess equimolar volumes vary in the order: tert-butylbenzene > sec-butylbenzene > n-butylbenzene. The VE in the studied systems increase as the rising temperature. The Redlich-Kister equation was applied to fit the experimental data. Using the coefficients of the Redlich–Kister equation, excess partial molar volumes at infinite dilution, V¯iE,∞ were calculated for the three binary systems. Molecular non-bond energy, E for binary mixtures at the mole fraction of 0.5 and temperature of 298.15 K also were calculated by the MD simulations. The Prigogine–Flory–Patterson theory and Graph-theoretical approach were examined for the suitability by correlating experimental VE data with compositions.