George C. Benson

Excess volumes of alkanol + alkane binary systems in terms of an association model with a flory contribution term

Abstract A model of associated mixtures is proposed, in which a chemical contribution term described by an athermal associated model is combined with a physical contribution term described by a Flory new theory formalism. Five adjustable parameters are used: three for representing the enthalpy, entropy, and volume of hydrogen bond formation, and two for correlating the Flory interaction parameter with molecular characteristics of the component molecules. The calculated excess molar volumes are in good qualitative agreement with experimental results for 1-alkanol + n -alkane mixtures comprising 1-alkanols from ethanol to dodecanol and n -alkanes from n -pentane to n -hexadecane. The compositions at which the excess molar volume changes sign, and the excess partial molar volumes of the components as functions of composition are also described.

Review of experimental and recommended data for the excess molar volumes of 1-alkanol + n-alkane binary mixtures

A review of excess volume data for (1-alkanol + n-alkane) systems and recommended data sets are presented. The review covers 54 systems in 207 data sets published up to 1991. The experimental data are represented in a reduced form as parameters of the best smoothing equation together with the standard and maximum deviations. For all data the temperature, pressure, number of data points, and method of measurement are given. Six recommended data sets are selected from the collected systems: methanol + n-heptane, ethanol + n-hexane, ethanol + n-heptane, 1-propanol + n-heptane, 1-butanol + n-heptane and 1-hexanol + n-hexane. Recommendation are also given for the five key systems of the IUPAC Project.

Excess molar enthalpies of methyl tert-butyl ether + n-hexane + (n-decane or n-dodecane) ternary mixtures at 298.15 K

Abstract Excess molar enthalpies, measured at 298.15 K in a flow microcalorimeter, are reported for the ternary mixtures x 1 C 5 H 12 O + x 2 C 6 H 14 + x 3 C v H 2 v +2 , with v = 10 and 12. Smooth representations of the results are described and used to construct contours of constant enthalpy on a Roozeboom diagram. An analysis of the results in terms of the Flory theory of mixtures is also presented.

Excess enthalpies for (di-n-propyl ether+n-alkane) at 298.15 K

Abstract Calorimetric measurements of excess enthalpies at 298.15 K are reported over the entire composition range for (di-n-propyl ether + n-hexane or n-octane or n-decance or n-dodecane or n-hexadecane). A correlation of the results in terms of the Flory theory of mixtures is described.

Excess enthalpies of (ethanol or 1-propanol) + methyl tert-butyl ether + n -octane ternary mixtures at 298.15 K

Abstract Zhu, S., Shen, S., Benson, G.C. and Lu, B.C.-Y., 1994. Excess enthalpies of (ethanol or 1-propanol) + methyl tert -butyl ether + n -octane ternary mixtures at 298.15 K. Fluid Phase Equilibria , 94: 217-226. Excess molar enthalpies, measured at 298.15 K in a flow microcalorimeter, are reported for the ternary mixtures (ethanol + methyl tert -butyl ether + n -octane) and (1-propanol + methyl tert -butyl ether + n -octane). Smooth representations of the results are described and used to construct constant enthalpy contours on Roozeboom diagrams.

Excess enthalpies of (ethanol + hexane + decane or dodecane) at the temperature 298.15 K

Flow-microcalorimetric measurements of excess molar enthalpies at the temperature 298.15 K are reported for the ternary mixtures {x1C2H5OH + x2C6H14 + (1 − x1 − x2)CvH2v+2} with v = 10 and 12. Smooth representations of the results are described and used to construct constant-enthalpy contours on a Roozeboom diagram. Comparisons with estimates from a DISQUAC model are also presented.

Excess enthalpies of (propan-2-one + an n-alkane) and of (4-methylpentan-2-one + benzene or toluene or cyclohexane or trichloromethane)

Excess molar enthalpies, measured in a flow-microcalorimeter, are reported for {x(CH3)2CO + (1 − x)CνH2ν+2} at 323.15 K for ν = 7, and at 313.15 K for ν = 10, 12, and 14, and for {xCH3COCH2CH(CH3)2 + (1 − x)(C6H6 or C6H5CH3 or c-C6H12 or CHCl3)} at 323.15 K. The dependence of the excess enthalpy on the mole fraction of ketone shows considerable variation for the different mixtures. A correlation in terms of a quasi-chemical group-contribution model was investigated for the mixtures containing propan-2-one.

Excess enthalpies of {(ethanol or propan-1-ol or methyl 1,1-dimethylethyl ether) + (2,3-dimethylbutane or 2,2,4-trimethylpentane)}

Excess molar enthalpies, measured at T = 298.15 K in a flow microcalorimeter, are reported for the six binary mixtures containing ethanol or propan-1-ol or methyl 1,1-dimethylethyl ether, together with 2,3-dimethylbutane or 2,2,4-trimethylpentane. Smooth representations of the results are presented, and an analysis in terms of an association model with a Flory contribution term is described.

Excess enthalpies and excess volumes of (methyl methacrylate + n-hexane) and (methyl methacrylate + n-heptane)

Flow-calorimetric measurements of excess enthalpies and successive-dilution dilatometric measurements of excess volumes are reported for (methyl methacrylate + n-hexane) and (methyl methacrylate + n-heptane) at 298.15 K.

Excess volumes of binary systems formed by a pyridine base and an n-alkane in terms of an association model

Abstract An approach proposed recently (Treszczanowicz and Benson, 1985) is applied to the description of the excess volumes of binary systems formed by mixing a pyridine base with an n-alkane. The pyridine bases are: pyridine, α-picoline, 2,4- and 2,6-lutidine and γ-collidine. n-Alkanes from n-hexane to n-decane are considered. The excess volumes are described as sums of two contributions. One arises from self-association of the pyridine base and is evaluated according to the Mecke—Kempter continuous association model. The other comprises equation of state and interaction effects, which are treated according to the Flory theory. Four parameters are used for each series of (pyridine base + n-alkane) systems. Three are the enthalpy, entropy, and volume of bond formation in the complex, and the fourth is the Flory interaction parameter X ‡ 12 for the system containing n-hexane. The model provides a good description of the excess volumes which are S-shaped (negative at low mole fractions of base) for n-hexane systems, changing to positive values for systems containing higher n-alkanes. With the same values of the parameters, the model also predicts excess enthalpies which are in reasonable agreement with experiment.